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The dosage of contrast agents for computed tomography contrast studies is calculated based on the parameter of actual body weight (ABW) to ensure reproducibility. The use of lean body weight (LBW) and adjustment for physique (lean or obese) improves accuracy. However, this method is complex, because LBW is not a general body parameter and requires a special device to measure. To solve this problem, contrast body weight (CBW), has been proposed as a new and simple parameter that considers physique. CBW is calculated by determining the blood volume ratio based on body height, ABW, and sex and can potentially correct for body size. It can be calculated by entering a formula in a Microsoft Excel sheet. Since CBW can be easily obtained using this general tool, we decided to compare the two body parameters of ABW and CBW. We compared ABW and CBW and demonstrated a higher correlation between CBW-based dosing and the amount of iodine used per body weight than with ABW-based dosing. CBW-based dosing allows correction for body size. This indicates that contrast enhancement over a spectrum of lean or obese examinees can be linearly evaluated. To date, this method has shown good results.

Flowering plants exhibit a wide variation in the resources they invest in dispersal structures (dispersal investment), but the environmental correlates still remain unclear in many cases. Canopy openness is predicted to be negatively correlated with dispersal investment, because selective pressures on increased dispersal investment, including host-specific natural enemies and the paucity and/or ephemerality of safe sites, will be more prevalent in shady sites. Here, we tested this prediction by firstly examining the correlation between dispersal investment and canopy openness as well as abundance of the representative natural enemy (rusts, Puccinia spp.) through seven populations of an ant-dispersed sedge, Carex lanceolata (Cyperaceae). Secondly we conducted a cafeteria experiment to verify the effect of intraspecific variation in dispersal investment on diaspore preferences of seed dispersing ants. Lastly, a seedling transplant experiment was performed to clarify whether seed dispersal distances by ants are sufficient to reduce infection by the rusts. We found a negative correlation between dispersal investment and canopy openness, thus supporting the prediction. Moreover, there were more signs of rust infection caused by Puccinia spp. on adult plant leaves in more shady sites. The cafeteria experiment showed that a large ant species (Formica japonica) with relatively long seed dispersal distances tended to prefer diaspores with greater dispersal investments, while smaller ant species with shorter dispersal distances preferred diaspores with lower dispersal investments. The seedling transplant experiment revealed that rust severity in sedge offspring was considerably reduced by the typical seed dispersal distance (ca. 4 m) afforded by the large ant species, F. japonica. The increased rust severity at shady sites, combined with the narrow dispersal ranges of rusts, can partially explain the negative correlation of dispersal investment with canopy openness. These results support the importance of canopy openness as a factor underlying the variations in dispersal investment seen among flowering plants.

Podocyte injury is involved in the onset and progression of various kidney diseases. We previously demonstrated that the transcription factor, old astrocyte specifically induced substance (OASIS) in myofibroblasts, contributes to kidney fibrosis, as a novel role of OASIS in the kidneys. Importantly, we found that OASIS is also expressed in podocytes; however, the pathophysiological significance of OASIS in podocytes remains unknown. Upon lipopolysaccharide (LPS) treatment, there is an increase in OASIS in murine podocytes. Enhanced serum creatinine levels and tubular injury, but not albuminuria and podocyte injury, are attenuated upon podocyte-restricted OASIS knockout in LPS-treated mice, as well as diabetic mice. The protective effects of podocyte-specific OASIS deficiency on tubular injury are mediated by protein kinase C iota (PRKCI/PKCι), which is negatively regulated by OASIS in podocytes. Furthermore, podocyte-restricted OASIS transgenic mice show tubular injury and tubulointerstitial fibrosis, with severe albuminuria and podocyte degeneration. Finally, there is an increase in OASIS-positive podocytes in the glomeruli of patients with minimal change nephrotic syndrome and diabetic nephropathy. Taken together, OASIS in podocytes contributes to podocyte and/or tubular injury, in part through decreased PRKCI. The induction of OASIS in podocytes is a critical event for the disturbance of kidney homeostasis.

We investigated the electrical properties and electronic structure of defect-containing chalcopyrite AgIn5Te8 and chalcopyrite AgInTe2. We found p-type AgIn5Te8 had worse electrical properties than AgInTe2, which is probably attribute to its lower mobility due to defects at its cation sites. Such defects would do the most to degrade its electrical properties because both compounds have similar valence band structure near the Fermi energy level. Conversely, n-type AgIn5Te8 might be a better thermoelectric material than AgInTe2, if not for its lower mobility, because it has better band structure, with multiple electron pockets at the high symmetry points in its conduction band.

Soft robots employ flexible and compliant materials to perform adaptive tasks and navigate uncertain environments. However, soft robots are often unable to achieve forces and precision on the order of rigid-bodied robots. In this paper, we propose a new class of mobile soft robots that can reversibly transition between compliant and stiff states without reconfiguration. The robot can passively conform or actively control its shape, stiffen in its current configuration to function as a rigid-bodied robot, then return to its flexible form. The robotic structure consists of passive granular material surrounded by an active membrane. The membrane is composed of interconnected robotic sub-units that can control the packing density of the granular material and exploit jamming behaviors by varying the length of the interconnecting cables. Each robotic sub-unit uses a differential drive system to achieve locomotion and self-reconfigurability. We present the robot design and perform a set of locomotion and object manipulation experiments to characterize the robot’s performance in soft and rigid states. We also introduce a simulation framework in which we model the jamming soft robot design and study the scalability of this class of robots. The proposed concept demonstrates the properties of both soft and rigid robots, and has the potential to bridge the gap between the two.

This paper describes the experimental evaluation of a robotic gripper's ability to perch on a variety of flat surfaces when used in conjunction with a free-flying robot in microgravity. The gripper is designed to be integrated with Astrobee, a free-flying robot deployed in the International Space Station (ISS) in April 2019. Astrobee was developed to help astronauts perform routine tasks while aboard the ISS. The robot has physical space for payloads such as a manipulator arm, which allows it to grasp grapple points such as handrails to conserve energy while maintaining a given position. However, grapple points are not always readily available. As such, the goal of this work is to have Astrobee perch onto other surfaces. To enable extended perching times, the gripper described here uses a gecko-like/electrostatic adhesive coupled with a cam-actuated mechanism designed to consume little to no energy while engaged with a surface. The gecko-like adhesives allow the gripper to easily attach and detach to/from surfaces through the camactuation mechanism. The gripper was tested in a simulated microgravity environment where it was mounted on a platform equipped with air bearings. This paper describes the gripper design and evaluates the gripper's attachment performance as a function of the platform's approach velocity and approach angle for several different target material types. The gripper perched on glass and acrylic substrates with over a 70% success rate. For carbon fiber/epoxy laminate and Kapton sheets the success rate was approximately 50%. The results showed a clear correlation between the approach velocity and approach angle for carbon and glass materials.

In this paper, we investigate the variation in performance of variable speed induction motors fed by inverters with grades of core materials used for stators and rotors from both results of measurement and finite element analysis. Identical shaped stator/rotor cores are manufactured by using several kinds of electrical steel sheets from low to high grades. Then, the characteristics of these motors are measured. Finite element analysis is applied to these motors to understand the measured results by separating losses and torques according to origins. The measured motor characteristics are found to be in good agreement with the results of the analysis. The analysis reveals the variation in each loss component with electrical steel sheets. Finally, the strong and weak points of the application of high-grade electrical steel sheets to the variable speed induction motors are discussed.

Reward removal is an essential step for seed dispersal mutualism because residual rewards inhibit germination. Nevertheless, variation in the reward removal efficiency (RRE) among dispersers and its consequences for germination have rarely been reported. In this study, we compared the RREs of two sympatric seed-dispersing ants, Formica japonica and Pheidole noda, using seeds of the ant-dispersed sedge Carex tristachya. Then, we conducted seed sowing experiments in a non-heated glasshouse to evaluate the effect of RRE on the percentage and speed of germination. The majority (85%) of seeds handled by F. japonica had residual elaiosomes, while elaiosomes were completely removed from all seeds handled by P. noda, demonstrating that P. noda has much higher RRE than F. japonica. The seed sowing experiments revealed that RRE, defined by the presence or absence of residual elaiosomes, was not associated with the percentage germination within a year. However, high RRE seeds with no residual elaiosomes germinated significantly faster than low RRE seeds with residual elaiosomes. Similarly, artificial removal of elaiosomes from C. tristachya seeds accelerated germination speed without affecting germination percentage. These results suggest that RRE is one of the most important parameters determining the effectiveness of a seed dispersal agent.

Purpose To assess the feasibility of Four-Dimensional Ultra-Low-Dose Computed Tomography (4D-ULDCT) for distinguishing pleural aspects with localized pleural adhesion (LPA) from those without. Methods Twenty-seven patients underwent 4D-ULDCT during a single respiration with a 16 cm-coverage of the body axis. The presence and severity of LPA was confirmed by their intraoperative thoracoscopic findings. A point on the pleura and a corresponding point on the outer edge of the costal bone were placed in identical axial planes at end-inspiration. The distance of the two points (PCD), traced by automatic tracking functions respectively, was calculated at each respiratory phase. The maximal and average change amounts in PCD (PCDMCA and PCDACA) were compared among 110 measurement points (MPs) without LPA, 16 MPs with mild LPA and 10 MPs with severe LPA in upper lung field cranial to the bronchial bifurcation (ULF), and 150 MPs without LPA, 17 MPs with mild LPA and 9 MPs with severe LPA in lower lung field caudal to the bronchial bifurcation (LLF) using the Mann-Whitney U test. Results In the LLF, PCDACA as well as PCDMCA demonstrated a significant difference among non-LPA, mild LPA and severe LPA (18.1 ± 9.2, 12.3 ± 6.2 and 5.0 ± 3.3 mm) (p Conclusions Four D-ULDCT could be a useful non-invasive preoperative assessment modality for the detection of the presence or severity of LPA.

Thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) is used to analyze polycyclic aromatic hydrocarbons (PAHs) in atmospheric fine particulate matter. However, despite the high sensitivity of TD-GC-MS, the recovery rate of PAHs is greatly influenced by active sites in the equipment. PAHs are decomposed or adsorbed at active sites, decreasing quantitative accuracy. Also, the thermal extraction of PAHs is easily affected by the matrix in PM2.5 samples, decreasing the thermal extraction efficiency. Herein, the analytical sensitivities of PAHs were improved by adding analyte protectant (AP) and thermal desorption aid (TDA) as an auxiliary agent. The combination of 2 µL of 0.5 w/v% D-sorbitol (as AP) and 2 µL of 10 w/v% Tween®20 (as TDA) was found to be most effective in improving the analytical sensitivity of PAHs. The sensitivities of 5–6-ring PAHs with high boiling points increased most when analyzing blank filter papers added with PAHs standard sample or real samples of PM2.5 compared with the samples without the auxiliary agent. When analyzing real samples of PM2.5, the peak areas of 5-ring and 6-ring PAHs in the PM2.5 sample added with the optimized auxiliary agent were 1.40 and 1.96 times that without the auxiliary agent. It is considered that AP in the auxiliary agent covered active sites and protected PAHs undergoing decomposition or adsorption. TDA improved the thermal extraction rate of high boiling point PAHs. When using alternative heat sampling equipment to analyze low concentrations of high boiling point components, the auxiliary agent proposed herein can increase the analytical sensitivity toward the target compounds.

Synchronisation of fruiting phenology with disperser activities is an important component of plant adaptation to seed dispersal mutualisms. Although most previous studies have exclusively evaluated the effects of fruiting phenology on seed removal rate, seed dispersal effectiveness is determined by both the number of dispersed seeds (quantitative effectiveness) and the probability of a dispersed seed becomes an adults (qualitative effectiveness). Therefore, the adaptive significance of fruiting phenology should be assessed for both components of dispersal effectiveness. This study investigates the adaptive significance of fruiting phenology for two ant-dispersed sedges, Carex lanceolata and C. tristachya. Because C. lanceolata is known to require a longer seed dispersal distance than C. tristachya, we hypothesized that C. lanceolata produces seeds when high qualitative dispersal effectiveness can be achieved, while C. tristachya bears seeds when seed disperser ants are abundant to give priority to quantitative dispersal effectiveness. Field observations of ant activity around the sedges revealed that the relative abundance of ant species with the longest seed dispersal distance, Formica japonica, was higher during the fruiting period of C. lanceolata than in that of C. tristachya, which is consistent with the requirement of C. lanceolata to achieve high qualitative effectiveness. In addition, our fruiting manipulation experiment revealed that C. tristachya fruits when the overall seed removal rate is high, resulting in high quantitative effectiveness. Overall, our results support the idea that variations in both qualitative and quantitative dispersal effectiveness should be considered to understand the adaptive significance of fruiting phenology in animal-dispersed plants.

Diarylethenes having trimethylsilyl and triethylsilyl groups at the reactive positions and their S,S-dioxidized diarylethenes were synthesized and their optical and thermal properties were investigated. Upon irradiation with ultraviolet light, the diarylethenes and thiophene-S,S-dioxidized diarylethenes underwent photochromic reactions from the colourless open-ring isomer to the coloured closed-ring isomer. The photogenerated closed-ring isomers were found to undergo thermal bleaching reactions to produce colourless byproducts. In particular, the thiophene-S,S-dioxidized diarylethene having a triethylsilyl group at the reactive positions underwent the thermal bleaching reaction even at −40 °C. Such materials could be used as light-starting irreversible thermosensors that can detect a rise in heat at low temperature.

An important feature of seed dispersal mutualism is the differentiation of dispersal-related seed traits (dispersal syndrome), which potentially contribute to partitioning of both seed dispersers and regeneration sites among sympatric plants. Yet, the selective factors underlying the diversity in dispersal syndromes are largely unknown. The differential requirements for seed dispersal distances are often proposed as a main factor in plant adaptations to disperser animals. Focusing on two sympatric ant-dispersed sedges Carex lanceolata and Carex tristachya (Cyperaceae), we tested the association of the adaptation to different dispersers with requirements for seed dispersal distances. We found that C. lanceolata was more frequently dispersed by the large ant Formica japonica (which had relatively long dispersal distances compared with other smaller ants) than by C. tristachya, and this was caused by the higher seed attractiveness of C. lanceolata to F. japonica. Pot experiments manipulating adult-to-seedling distances showed that isolation from conspecific adults only benefited C. lanceolata seedlings, and C. tristachya seedlings were not affected. These results support the importance of differential requirements for seed dispersal distances as a factor underlying the diversity in dispersal syndromes among animal-dispersed plants.

Diarylethenes having a benzofuryl group and their thiophene- S , S -dioxidized diarylethenes were synthesized and their optical properties and thermal stability were investigated. Upon oxidation of the thiophene ring, the optical properties such as absorption maxima, photocycloreversion quantum yields, and conversion from the open-ring isomer to the closed-ring isomer have changed. On the other hand, the thermal stability of the closed-ring isomers of the S , S -dioxidized diarylethenes is significantly higher than those of thiophene- S , S -dioxidized diarylethenes having a phenylthienyl group instead of a benzofuryl group. The high thermal stability of the closed-ring isomer was quantitatively discussed based on ground state energies obtained by quantum chemical calculations.

This paper introduces electrostatic and ultrasonic techniques to clean dust and other contaminants from the surface of a gecko-like, microstrutured adhesive. The result is a non-destructive, non-contact cleaning method that will afford robotic grippers, climbing robots, and perching robots the ability to operate in real-world environments. Experimental results show that the cleaning efficiency for three different sizes of glass beads, 53–75 um, 75–90 um, and 90–106 um, ranges between 75–99% when using a combination of electrostatic and ultrasonic cleaning. This is a far higher efficiency than when using electrostatic repulsion alone. Experiments also demonstrate an approximately 33% recovery in shear stress on a flat glass for a contaminated directional gecko-like adhesive after contact with a dusty table when electrostatic/ultrasonic cleaning was used. Finally, by applying this method on a robotic gripper, we observed an 18% recovery in normal adhesion on a flat glass substrate.

A novel surface activation technology for Cu-Cu bonding-based wafer-level vacuum packaging using hot-wire-generated atomic hydrogen treatment was developed. Vacuum sealing temperature at 300 °C was achieved by atomic hydrogen pre-treatment for Cu native oxide reduction, while 350 °C was needed by the conventional wet chemical oxide reduction procedure. A remote-type hot-wire tool was employed to minimize substrate overheating by thermal emission from the hot-wire. The maximum substrate temperature during the pre-treatment is lower than the temperature of Cu nano-grain re-crystallization, which enhances Cu atomic diffusion during the bonding process. Even after 24 h wafer storage in atmospheric conditions after atomic hydrogen irradiation, low-temperature vacuum sealing was achieved because surface hydrogen species grown by the atomic hydrogen treatment suppressed re-oxidation. Vacuum sealing yield, pressure in the sealed cavity and bonding shear strength by atomic hydrogen pre-treated Cu-Cu bonding are 90%, 5 kPa and 100 MPa, respectively, which are equivalent to conventional Cu-Cu bonding at higher temperature. Leak rate of the bonded device is less than 10−14 Pa m3 s−1 order, which is applicable for practical use. The developed technology can contribute to low-temperature hermetic packaging.

Operational transfer path analysis (OTPA) calculates contributions of reference points to response point vibration by using only operational data. Through OTPA, effective interior noise and vibration reduction are achieved by applying intensive countermeasure to the high contributing part. However, it becomes difficult occasionally when many reference points have similar contributions by a vibration mode. In this case, obtaining high contributing vibration mode and considering how to reduce the mode become important information. In this study, we attempted to calculate the vibration mode contribution by modifying OTPA. Principal component calculated in OTPA procedure is composed of correlated vibration factors among reference points. We then considered the relationship between the principal component and the vibration mode, and associated the principal components with the vibration modes of a test structure. As a result, high contributing vibration modes to the response point could be found. In addition, information about which side of the structure (response or reference side) had better to be measured intensively was also obtained by evaluating the influence of each principal component to the response point (principal component transfer function). Finally, Several countermeasures were applied to the structure considering the principal component and vibration mode contributions. The result shows effective vibration reduction at the response point could be carried out. Through these procedures, the modified OTPA became more useful tool for applying effective countermeasure.

In this paper, we investigate the variation in characteristics of variable speed induction motors fed by inverters with grades of core materials used for stators and rotors from both results of measurement and finite element analysis. Identical shaped stator/rotor cores are manufactured by using several kinds of electrical steel sheets from low to high grades. Then, the characteristics of these motors are measured. The finite element analysis is applied to these motors to understand the measured results by separating losses and torques according to origins. The measured motor characteristics are found to be in good agreement with the results of the analysis. The analysis reveals the variation in each loss component with the electrical steel sheets. Finally, the strong and weak points of the application of high grade electrical steel sheets to the variable speed induction motors are discussed.

This article reports a wafer-level heterogeneous integration and vacuum packaging technology by thermo­compression bonding using electroplated Cu sealing frame planarized by single-point diamond fly-cutting. A high grain boundary density on the Cu surface induced by mechanical stress application during fly-cutting process enables vacuum sealing with bonding temperature as low as 250°C. At such low bonding temperature, a less amount of gases is desorbed, resulting in a sealed cavity pressure lower than 100 Pa. Furthermore, the shear strength higher than 150 MPa using 50 μm width sealing frames is also achieved. The availability of the proposed technology as an integration platform for wafers with several μm structure is also demonstrated.

For animal-dispersed plants, evolutionary direction of seed traits is largely determined by the trait preference of disperser animals. Thus, clarifying conditions determining the disperser's preferences is important for understanding the evolution of dispersal traits in animal-dispersed plants. The intensity of the interference competition among dispersers may be a factor affecting the seed trait preference of disperser animals, because it often weakens the food preference of various animals. To test this possibility, we examined correlation between the intensity of interference competition among disperser ants and their trait preference for seeds of an ant-dispersed sedge, Carex tristachya Thunb. (Cyperaceae). By a cafeteria experiment conducted in the field, we first confirmed the overall preference by disperser ants for the elaiosome, which is a seed appendage facilitating the dispersal by ants. Second, we detected the negative correlation between the preference for elaiosomes and the frequency of interference among ants at a depot. Third, we compared this trend between dominants and subordinates of ants and revealed that the negative correlation was seen only in dominant species. These results suggest that the intensity of interference competition and the variation in its effect on animal species at different social status play important roles for the evolution of seed traits via the modification of seed trait preference by disperser animals.

症例は52歳,女性,主訴は右鎖骨上窩拍動性腫瘤で, 48歳時左腎癌で左腎摘をうけた.その後,経過観察中であったが,偶然右鎖骨上窩の拍動性腫瘤を指摘された. CT,血管造影で右鎖骨下動脈近位側に動脈瘤が判明した.脳血管造影では左右のWillis輪を介する交通はみられなかった.皮切は胸骨正中切開に頸部横切開を追加した.動脈瘤の中枢および末梢側でのテーピングが可能で,瘤切除,端端吻合を行った.瘤壁の平滑筋および弾性線維の減少,粘液変性がみられた. 右鎖骨下動脈近位側に発生する動脈瘤の手術に際しては,術中脳血流の確保に十分な考慮が必要である.

Most recently low-dose (4E17 ions/cm2) SIMOX technology has been developed in order to restrain the dislocation density and the production cost. However, in- and out-diffusion of oxygen and internal oxidation (ITOX) phenomena have never been understood during high-temperature annealing process as yet. In this study, we use the sample, which was implanted 18 O + with the dose of 4E17 ions/cm2 into silicon substrate and then non-oxidizing anneal was done at around 1300 °C. As the results, it was proven that the diffusion of oxygen into thermal oxide layer above 1300 °C was not in agreement with the Deal–Grove theory. The mechanism of oxygen in- and out-diffusion in SIMOX wafer is discussed.

Selective oxidation in silicon steel shows several interesting phenomena, such as the formation of an internal oxidation zone that depends on the oxidation conditions and the steel composition. In this work, SIMS and XPS were used for characterizing the formation processes of surface layers formed during selective oxidation of a typical silicon steel. The starting material is a secondary-recrystallized 3 mass% Si-steel sheet with a surface orientation of (011). Sample sheets were annealed at a temperature of 948–1023 K under an atmosphere with a low partial pressure of oxygen. The SIMS depth profiles show that the internal oxidation zone thickens and an iron-rich layer that formed on the internal oxidation zone expands as the annealing temperature increases. Manganese and chromium levels increase outside the internal oxidation zone, whereas tin exists in the internal oxidation zone. The XPS results of the sample surface show that silicon and manganese levels increase on the sample surface to form oxides, and the chemical composition and state of these elements depend on the annealing temperature. In addition, tin increases on the surface of a relatively thick iron-rich layer that formed on the internal oxidation layer. These experimental results are discussed on the basis of the thermodynamic characteristics of the elements. Copyright © 2003 John Wiley & Sons, Ltd.

A silicon nitride film was deposited on an Si(100) substrate with a silicon dioxide surface layer from NH 3 and SiH 2 Cl 2 by low-pressure chemical vapour deposition under various conditions. The etching rates of the silicon nitride films by buffered hydrofluoric acid (BHF) were investigated using Rutherford backscattering spectroscopy. The change of the etching rate at the interface region suggested the existence of a transition layer on the interface between the silicon nitride film and the silicon dioxide layer on the substrate. The silicon concentration of the transition layer is higher than that of the silicon nitride. The existence of a transition layer was also confirmed by angular-resolved XPS. Measurement of the etching rate of the silicon nitride films by BHF was applied to clarify the relation between the deposition conditions of the silicon nitride films and the thickness of the transition layer. The growth of the transition layer was controlled by nitridation of the substrate in ammonia ambient before deposition of the silicon nitride film.

We report successful local resection for cancer of papilla of Vater in an 86-year-old woman. She was referred to our hospital because of right hypochondralgia. Abdominal ultrasonography and computed tomography showed marked dilatation of the common bile duct (CBD). Endoscopic retrograde cholangiography disclosed a small shadow defect in the terminal of the dilated CBD. Biopsy of the papilla revealed well-to-moderately differentiated adenocarcinoma. Considering her extreme old age and keeping in mind her quality of life after the operation, and the finding that the tumor was localized within the papilla and highly differentiated, we performed local resection. In addition, the intrapancreatic portion of the CBD and part of the main pancreatic duct (MPD) were further resected to secure a negative margin, confirmed by frozen section. The MPD was reapproximated to the duodenal mucosa and a choledocho-duodenostomy was performed for CBD reconstruction. Histopathological examination showed the tumor was papillary adenocarcinoma, 10 x 15 mm in size; there was no invasion beyond the sphincter of Oddi, it had partly infiltrated the CBD, but had not invaded to the pancreas or duodenum. The patient's postoperative course was not eventful and she has had good quality of life for the past 6 years since the operation, without any evidence of recurrence. Although radical pancreaticoduodenectomy is now the standard procedure in patients with malignant tumor of the papilla of Vater, local resection is a reasonable alternative for high-risk patients with highly differentiated, apparently localized carcinomas.

Small bowel allograft rejection in large animals has yet to be well defined. There are no specific early signs of graft rejection. The present experiments were undertaken to compare acute small bowel allograft rejection in pigs with and without FK506 and also to examine the usefulness of mucosal biopsies. Thirty-six outbred Large-White pigs were divided into (1) group 1 (n = 9): nonimmunosuppressed recipients; (2) group 2 (n = 8): FK506-immunosuppressed recipients; (3) group 3 (n = 2): autotransplant controls; and (4) donors (n = 17). Orthotopic small bowel transplantations were performed with Thiry-Vella loops for daily biopsies. The survival rate of group 2 was significantly longer than that of group 1 (P0.05). One best survivor in group 2 was killed at postoperative day (POD) 365. Treatment by FK506 prevented rejection, but most of the pigs died of pneumonia. In group 1, rejection began on POD 3 and progressed to severe rejection rapidly within 7 days. In group 2, rejection began from POD 6 to POD 8, but either remained mild or spontaneously improved. The differences in the routine laboratory data and the tumor necrosis factor-alpha level were not evident between the groups. Histological studies of repeated graft biopsies are thus considered to be essential for detecting signs of graft rejection.