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This paper introduces the design and implementation of a 5 T magnetic resonance radio frequency power amplifier (RFPA), which can be used in scan rooms without a circulator. The RFPA was designed based on laterally-diffused metal-oxide semiconductor (LDMOS) power tube with high standing wave tolerance, and it contained a three-stage amplifier circuit. The transmission line transformers with magnetic core in RFPA was designed as non-magnetic. The reflected power was monitored tensely. The nonlinear automatic correction of RFPA was realized by using analogic negative feedback technology. The results showed that the output of RFPA power is up to 2 kW, the gain linearity performance is less than or equal to 1 dB, and the phase linearity performance is less than or equal to 10 deg over 40 dB range up to rated power during the load disturbance (reflection coefficient Г < 0.5), which meets the imaging requirements. Thus the rationality and feasibility of the proposed design scheme are verified.

Background and objective Lung cancer is one of the most common malignancies. The aim of this study is to investigate the relationship between the change of lymphocyte subsets in the peripheral blood of lung cancer patients and the survival rate. Methods Flow cytometry was used to measure the percentages of lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, CD25+, CD44+, and NK cells) in peripheral blood obtained from 221 patients with primary lung cancer without any treatment and from 96 healthy blood donors as the control group. The result was combined with clinical and follow-up data and statistical analysis was conducted. Results The levels of CD3+ and CD8+ in the patient group are significantly lower compared with the control group, whereas the levels of CD4+/CD8+, CD19+, CD25+, CD44+, and NK cells are significantly higher (P0.05) in the NSCLC group. The level of CD3+ was significantly higher compared with the pre-chemotherapy group, but NK cell, CD19+, and CD44+ were distinctly lower in the post-chemotherapy group (P

The plate count method has been used as a classical method at home and abroad for the aerobic bacterial count in cosmetics, which is simple to operate, but it takes a long time to complete the entire detection process. With the development of microbiological technology, a variety of rapid microbial counting methods based on various principles have been gradually developed. By comparing the advantages and disadvantages of the plate count methods and various rapid microbial counting methods for the aerobic bacterial count in cosmetics, the length of detection time, the accuracy of the aerobic bacterial count, and the feasibility of rapid microbial counting method in the detection of aerobic bacterial count in cosmetics were comprehensively considered. It can be concluded that the fluorescence microscopy counting method and flow cytometry counting method have potential in the detection of aerobic bacterial count in cosmetics. The reasons are as follows, TEMPO® counting method, molecular biology counting method, ELISA (enzyme-linked immunosorbent assay) counting method, optical biosensors counting method, and mass spectrometry counting method have high specificity for bacteria and are only suitable for quantification of certain microorganisms, while microbial metabolism counting method, microfluidics counting methods, MicroSnapTM counting method, and Simplate™ counting method require microbial culture, thus preservatives in cosmetics will affect the accuracy of the total number of microorganisms in the sample. Although the fluorescence intensity counting method is suitable for the aerobic bacterial count in cosmetics, its sensitivity is quite low. The fluorescence microscopy counting method and flow cytometry counting method are suitable for the aerobic bacterial count in cosmetics for two reasons. The first reason is that the fluorescence microscopy counting method and flow cytometry counting method directly count the number of microorganisms in the sample so that the detection time is shorter. The second reason is that there is no need for microbial culture. Therefore, there is no need to consider the inhibitory effect of preservatives in cosmetics on microbial growth, so that the detection accuracy is higher. The introduction of rapid microbial counting methods into the standard system of the aerobic bacterial count in cosmetics, as a supplement to the current standard, is of great significance for aerobic bacterial count in cosmetics. [ABSTRACT FROM AUTHOR]

PURPOSE: To study the changes of mechanical properties of thermodynamic nickel-titanium (NiTi) archwires under 37 degrees centigrade and in artificial saliva. METHODS: Using a modified partial dental arch-bending device, 4 types of 0.016-inch in diameter thermodynamic NiTi archwires were tested in 37degrees centigrade artificial saliva and at different moments in 8 weeks. An Instron Universal Testing Machine delivered deflections of 3mm in the lateral incisor area. The load-deflection curves were determined from the passive position to deflections of 3mm. The following variables from unloading curves were calculated, the load value at 1.5mm of unloading deflection point (UDP), stiffness between 0.5mm UDP to 2.5mm UDP after unloading. Statistically significant differences in these variables for different brands and moment were analyzed using one-way analysis of variance with SPSS11.5 software package. RESULTS: The load-deflection curves of A, B and D archwires were very similar at 0-week and 4-week, while their loading curves rised obviously at 8-week. The load-deflection curves of C archwire had significant differences at 3 moments. The load value of 1.5mm UDP of A,B and D archwires had insignificant difference at 8-week,the unloading force value of C archwire increased slightly at 8-week. There were a few fluctuations of the unloading stiffness of B and D archwires, while A and C archwires's unloading stiffness had a tendency to decrease. CONCLUSIONS: Thermodynamic NiTi archwires always exhibited superelasticity and SME in 8 weeks. Clinically, thermodynamic NiTi archwires can still deliver forces continuously when they are loaded for 2 months even longer. [ABSTRACT FROM AUTHOR]

The necessity of the research of easy-care and the cause of fabric's creases are stated. The principle of easy-care and crease resistance are compared, and it is showed by schematic drawing. The crease recovery angle test method is illustrated, and the other three methods are introduced including wring method, fall into water and become deformed method and wash in washing machine method. By this way, the easy-care is evaluated in five grades. From internal factors and external factors, influences of the easy-care are analysed. In the process of finishing, the formaldehyde scavengers which are widely used are introduced. They are used to reduce the formaldehyde. [ABSTRACT FROM AUTHOR]

Magnesium methacrylate (MgMA)/ hydrogenated nitrile rubber (HNBR) composites were prepared by blending MgMA with HNBR, and the effects of MgMA amount on mechanical properties of HNBR at high temperature and after immersion in drilling fluid were investigated. The results showed that under the combined action of high temperature and drilling fluid, the comprehensive performance of MgMA/HNBR composite was improved most significantly with higher tensile strength, elongation at break and tear strength, and the best thermal-oxydative aging resistance, when the amount of MgMA was 8 phr (mass).

Perioperative blood volume monitoring and treatment is an important part of clinical anesthesia, which is essential for restoring effective blood volume, ensuring oxygen supply to organs and tissues, and stabilizing the internal environment. It is also an important part of rapid recovery after surgery. Selecting appropriate blood volume monitoring methods and reasonable fluid therapy during the perioperative period can optimize the hemodynamics of patients. But there is still some controversy about the intraoperative blood volume monitoring scheme. This article intended to analyze and review the characteristics and clinical value of various perioperative blood volume monitoring methods, and explore the strategies of perioperative blood volume monitoring and treatment, so as to provide a theoretical basis for preventing or reducing postoperative complications and improving the prognosis of patients.

The objective of this work was to study the effects of different light treatments on the color development of peach skin during postharvest storage and to explore the regulatory mechanism of light on anthocyanin metabolism. Peach fruits, cv. Zhongtao 9, were subjected to different lights (red, green, blue and white) for 12 h and darkness for another 12 h at (22 ± 1) ℃, while those kept in darkness for 24 h were considered as a control. The variations in fruit skin color, anthocyanin content and enzymatic activities involved in the anthocyanin metabolic pathway, as well as the expression levels of the structural genes of anthocyanin biosynthesis and related transcription factors after light treatment were measured. The results showed that the color development of peach skin was not affected by red and green light, but was weakly promoted by white light and significantly induced by blue light. The anthocyanin content in blue light-treated peach skin was 27.26 mg/kg, which was 4.48 and 10.34 times as high as that in the white light treatment and control groups on the sixth day after harvest, respectively. Under blue light treatment, the enzymatic activities of the anthocyanin biosynthesis pathway and the expression levels of structural genes and transcription factors were significantly higher than those in the control and other light treatment groups at most of the time points tested (P < 0.05). The expression levels of the structural genes PAL, CHS, F3H, DFR, ANS and UFGT and the transcription factor MYB10.1 showed significantly positive correlation with the color parameters and anthocyanin content of peach skin. Collectively, this study indicated that blue light treatment promoted the synthesis and accumulation of anthocyanins in peach skin by up-regulating the anthocyanin synthesis pathway, which will deepen the understanding of the regulatory mechanism of anthocyanin metabolism by light in plants and provide a theoretical basis for the development of postharvest technologies to improve peach skin color.

Objective To screen and establish a spontaneously high organotrophic cell subline of metastatic breast cancer and to validate characteristic and the organotropism of the lung metastasis cell subline obtained from the screening. Methods By using the experimental lung metastasis, mouse breast cancer cells line 4T07 were injected into tail vein of mouse. Retrieving metastatic tumor cells in the lung and enriching them in vitro; By using the spontaneous metastasis model, the mammary fat pad was inoculated with tumor cells. Combined with the in vitro expansion culture of lung metastasis and repeated three times, a lung organotrophic cell sub-line and model of spontaneous lung metastasis were obtained; A highly metastatic cell subline stably expressing luciferase was obtained by transfection and screening. Cell morphology was microscopied with HE staining and an in vivo imaging system was performed to detect the migration and lung-specific metastasis. Flow cytometry was used to analyze the changes of immune cells in primary site, metastasis and spleen. Wound healing and Transwell assays were performed to detect migration of cell lines in vitro. Results A mouse breast cancer lung-specific metastatic cell subline (4T07LuM) was successfully established. in vivo imaging results validated that the fluorescent signal was mainly concentrated in the lung after injection of 4T07LuM cells labeled with luciferase in situ. HE staining microscopy results verified tumor metastasis in the lung. In addition, according to the results of Transwell and wound healing assays, 4T07LuM, compared to the parental cells 4T07, had shown a significantly more invasive migration(P＜0.001). Finally, according to the results of flow cytometry detection, 4T07LuM cell had showed significantly altered the immune cell ratios as compared to that of 4T07 cell. The immune microenvironment in vivo was more inclined to an immuno-suppressed state. Conclusions Cell sublines with high organ-specific metastasis ability are obtained through combination of serial screening of experimental and spontaneous metastasis and in vitro culture expansion.

Aiming at clarifying the corrosion behavior of oil casing materials in high salinity and high temperature annulus protection fluid environment, the corrosion damage sensitivity of oil casing materials under non-stressed and stressed conditions in the simulated oilfield annulus protection fluid environment was evaluated by high temperature and high pressure (HPHT) test system. The micromorphology, cross section characteristics and chemical composition of the product film on the surface of the material were analyzed and characterized by scanning electron microscope and energy dispersive spectrometer. Results showed that the corrosion of the material was relatively worse in the annulus protection liquid without deoxygenation treatment. The corrosion product film was cracked and partially detached, and the cracking of the bottom film layer could be seen at the shedding place. Moreover, the average corrosion rate of P110 material was up to 3.83 mm/a. Observing the cross section could find the cracking on the surface of the double film layer was limited to the corrosion product film, and the substate material was not involved. The material was uniformly corroded and thinned. Furthermore, after deoxygenation treatment, the erosion of the annulus protection fluid decreased significantly, and the corrosion rate of P110 material decreased by 80%. Generally, P110 and P110SS were insensitive to stress corrosion cracking under the synergistic effect of high temperature and high pressure annulus protection fluid without deoxygenation treatment environment and loading stress, and corrosion thinning was the main corrosion damage mode of P110 oil casing material.

Objective To investigate the effect of miR-17-5p expression on the injury of human lung adenocarcinoma alveolar basal epithelial cell line A549 induced by Streptococcus pneumonia and its mechanism. Methods A549 cells was divided into control group,infected group(1×108 CFU/mL S.pneumoniae),anti-miR-17-5p intervention group (transfected with anti-miR-17-5p before S.pneumoniae infection),anti-miR-NC intervention group (transfected with anti-miR-NC before S.pneumoniae infection), and pcDNA-ALDH2 intervention group(trans- fected with pcDNA-ALDH2 before S.pneumoniae infection),and pcDNA intervention group (transfected with pcDNA before S.pneumoniae infection).The level of miR-17-5p and ALDH2 mRNA was detected by RT-qPCR. IL-6 and IL-10 in cell culture supernatant were detected by enzyme-linked immunosorbent assay. Apoptosis was detected by flow cytometry. ALDH2, Bcl-2 and Bax protein were detected by Western blot. Dual luciferase assay verified the targeting relationship between miR-17-5p and ALDH2. Results Compared with the control group, the level of miR-17-5p in the infected group was significantly increased (P＜0.05), while mRNA and the protein concentration of ALDH2, IL-10 and Bcl-2 were significantly decreased (P＜0.05). However, apoptotic rate and the levels of IL-6 and Bax were significantly increased (P＜0.05). Compared with the infected+anti-miR-NC group, IL-10 and Bcl-2 in the infected+anti-miR-17-5p group were significantly increased(P＜0.05), the apoptotic rate, IL-6 and Bax were significantly decreased (P＜0.05). Compared with the infected+pcDNA group, the levels of IL-10 and Bcl-2 in the infected+pcDNA-ALDH2 group were significantly increased (P＜0.05), and the apoptotic rate and the levels of IL-6 and Bax were significantly decreased (P＜0.05).miR-17-5p negatively regulated ALDH2 expression.Inhibition of ALDH2 expression reversed the effect of inhibiting miR-17-5p expression on S.pneumoniae-induced A549 cells damage. Conclusions Inhibition of miR-17-5p expression reduces S.pneumoniae-induced the damage of the cell line A549 by regulating ALDH2.

Objective To investigate the expression of miRNA⁃449b in gliomas and its effect on cell proliferation and invasion. Methods The expression level of miRNA⁃449b was detected by locked⁃oligonucleotide⁃probe in situ hybridization (ISH) in 60 human glioma specimens of different WHO grades and 10 non⁃tumoral control brain tissues. miRNA⁃449b was quantified by Stem⁃loop quantitation real⁃time polymerase chain reaction (qRT⁃PCR) with U6 as the internal control in U251, LN229 and UC2 cells. EdU staining, MTS method, flow cytometry assay (FCM), Phalloidin staining and Transwell assays were used to evaluate the effect of miRNA⁃449b on the proliferation and invasion of U251 and LN229 cells. Results The expression of miRNA⁃449b was decreased in gliomas compared with that in the non⁃tumoral control brain tissues (P < 0.001, for all), and was significantly declined with the elevation of glioma grades (P < 0.001, for all). miRNA⁃449b level was significantly lower in U251 and LN229 cells than that in UC2 cells (P = 0.001, 0.002). The relative expression of miRNA⁃449b in U251⁃miRNA⁃449b group was higher (P < 0.001), while EdU⁃positive rates (P = 0.029) and cell proliferation (P = 0.004, 0.001, 0.002) was lower than U251⁃Scr group; the relative expression of miRNA⁃449b in LN229⁃miRNA⁃449b group was higher (P < 0.001), while EdU⁃positive rates (P = 0.032) and cell proliferation (P = 0.003, 0.001, 0.004) was lower than LN229⁃Scr group. The percentages of each phase G 0 /G 1 in U251⁃miRNA⁃449b group and LN229⁃miRNA⁃449b group were higher than those in U251 ⁃ Scr group (P < 0.001) and LN229 ⁃ Scr group (P = 0.018) respectively, cell proliferation were lower than U251⁃Scr group (P = 0.002) and LN229⁃Scr group (P = 0.005). F⁃actin was centralized mostly on cell cortex or lamellae in the groups of U251⁃Scr and LN229⁃Scr, whereas diffusely distributed in the groups of U251⁃miRNA⁃449b and LN229⁃miRNA⁃449b. Conclusions miRNA⁃449b is an important tumor⁃suppressive miRNA and its downregulation may be an important cause leading to tumorigenesis of glioblastoma, which could be used as a valuable biomarker to assess the malignant degree of gliomas. Furthermore, the exogenous miRNA⁃449b could effectively inhibit the proliferation and invasion abilities of glioma cells, confirming it has potential value in malignant gliomas therapy. DOI：10.3969/j.issn.1672⁃6731.2019.11.007

Objective To evaluate the effect of Myozyme on one ventilator dependent patient with late-onset glycogen storage disease typeⅡ (GSDⅡ). Methods Myozyme infusion was administered based on manufacturer's recommendations at 20 mg/kg every 2 to 4 weeks, beginning at actual body weight, and was continuously treated for 6 times. No premedication was performed except 5 mg dexamethasone was administered at the first use of Myozyme. Clinical assessment was completed every day and was lasted for 16 months including motor function, the time free of ventilation, and the change of respiration parameters. Results Myozyme was well tolerated without adverse reactions. Pain on shoulder began to alleviate the next day after taking Myozyme. With the prolonged time and increased number of taking drugs, the time free of ventilation and doing in-situ stepping prolonged, and the speed of stepping in-situ also increased. Besides, the strength of lifting the upper limbs increased, and both the time and speed of walking free of ventilation prolonged. The maximus curative effect occured at the 7th month (3 months after drug withdrawal) after treatment and returned to pre-treatment levels at the 8th month (4 months after drug withdrawal). The pain on shoulder was the first symptom that got improved, and the fastest symptom that returned to baseline. Conclusions Myozyme has positive effect on ventilated patients with late-onset glycogen storage disease type Ⅱ. doi: 10.3969/j.issn.1672-6731.2014.05.009

Objective: To evaluate the molluscicidal effect of niclosamidate against Oncomelania hupensis in laboratory and explore its mechanism by determining the enzyme activities of six important enzymes in snail soft tissues., Methods: O. hupensis snails were treated with niclosamidate at the concentration of 1.25 mg/L for 24 h and the snail soft tissues were separated and prepared for analysis. The enzyme activities of NOS, AChE, SDH, LDH, ACP and AKP were determined by ultraviolet spectrophotometry. The morphology of the snail soft tissue was also observed., Results: Niclosamidate exhibited a potent molluscicidal effect against O. hupensis at the concentration of 5.00 mg/L with a mortality of 96.67% by the immersion method in laboratory. After immersed with niclosamidate (1.25 mg/L) for 24 h, the enzyme activities of NOS, AChE, ACP and AKP were significantly decreased compared with those of the controls (all P < 0.01). There were no significant changes observed in the enzyme activities of SDH and LDH (both P > 0.05)., Conclusions: Niclosamidate possesses a potent molluscicidal effect against O. hupensis and its molluscicidal mechanism is probably by affecting the transmission of neurotransmitters, interfering with the circulation, metabolism and motor functions that require NO, and hindering the digestion and absorption of nutriments, which eventually result in the death of the snails.

Ectopic tooth is a common problem reported in clinics. Ectopic tooth generally occurs around its primary position, and long-distance displacement is rare. A case of ectopic maxillary premolar in palatal suture with a supernumerary tooth in the mentum region was reported in this study, and the relevant literature is presented in this paper.

Objective: Acute mountain sickness (AMS) is a common condition in individuals who ascend to altitudes over 2 500 m. There is no measurements that can reliably predict or diagnose this condition. We therefore determined whether pulse oximetry data are associated with the development of AMS and can help diagnose AMS., Methods: We studied 58 young male undergraduates who traveled from Chongqing (300 m) to Lhasa (3 658 m) by train. We collected data on the ascent profiles and AMS symptoms based on the Lake Louise Score (LLS). The resting arterial oxygen saturation (R-SpO 2 ) and pulse rate were then measured using finger pulse oximetry., Results: In Golmud(2 800 m) and Tanggula(5 200 m), R-SpO 2 was significantly lower in the AMS group than in the group without AMS ( P <0.05). However, upon arrival in Lhasa (3 658 m), the R-SpO 2 was higher in the AMS group than in the non-AMS group ( P <0.05). In Tanggula, the change in the SpO 2 (CR-SpO 2 ) in the AMS group was higher than that in the non-AMS group ( P <0.05). But in Lhasa, the CR-SpO 2 in the AMS group was lower than that in the non-AMS group ( P <0.05). We also monitored heart rate (HR) throughout the study. In Xining(2 200 m) and Golmud, the HRs in the AMS group were higher than those in the non-AMS group. However, the HRs in the AMS group were lower than those in the non-AMS group in Tanggula and Lhasa., Conclusions: Based on the results of this study, the R-SpO 2 graph was not consistent. We can thus conclude that the utility of SpO 2 remains limited in the diagnosis of AMS. The results suggest that using pulse oximetry to diagnose AMS is not valuable in people ascending to Lhasa on the Qinghai-Tibet train.