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AimIt has been shown that G-protein-coupled receptor kinase 2 (GRK2) negatively regulates the insulin-like growth factor 1 receptor (IGF1R) signalling pathway in hepatocellular carcinoma (HCC). The aim of this study was to evaluate the clinicopathological and prognostic significance of GRK2 and IGF1R in HCC.MethodsExpression of GRK2 and IGF1R was first detected by tissue microarray-based immunohistochemistry in 156 patients with HCC. Staining results, termed the H-score, were then correlated with clinicopathological variables and patient survival. Finally, the prognostic value of GRK2 and IGF1R was validated in the publically available TCGA (The Cancer Genome Atlas) RNA-sequencing database.ResultsThe H-score of GRK2 staining (which was significantly lower in tumour than non-tumour tissue) was negatively associated with that of IGF1R with a reverse trend. No clinicopathological significance of the proteins was found except for a relationship between tumoral IGF1R expression and tumour–node–metastasis stage. In univariate analysis, high IGF1R expression predicted poor overall and disease-free survival, whereas GRK2 was not prognostic. In multivariate analysis, IGF1R was significant for overall survival. Furthermore, IGF1R was also of prognostic value in the TCGA database.ConclusionsOur data indicate that GRK2 and IGF1R show a negative correlation in HCC. IGF1R could be a potential marker of poor prognosis for this malignancy.

A novel kind of AgNPs catalyst was synthesized by in-situ reduction method using poly(2-acrylamido-2-methyl propyl sulfonic acid-co-2-hydroxyethyl methclate) [short as P(AMPS-co-HEMA)] hydrogel as matrices and AgNO3as a metal precursor. The structure of the composite hydrogel was characterized by Scan Electrical Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The results showed that AgNPs were binded with end group and most of the particles were isolated and uniformly distributed on the P(AMPS-co-HEMA). The catalytic properties in the reduction reaction of 4-nitrophenol(shorted as 4-NP) to 4-aminophenol(shorted as 4-AP) were studied in detail, and the result showed that conversion rate and conversion efficiency attained 97.56% and 0.9671 mmol/g·min when the amount of AgNPs was 9mg, [NaBH4] was 2.0×10−1mol/L, [4-NP] was 2.0×10−2mol/L and the total volume of solution was 50 mL, respectively.

Objective To investigate the clinical features of unicentric Castleman's disease(UCD)with paraneoplastic pemphigus(PNP)and bronchiolitis obliterans(BO).Method Data of UCD patients with PNP and BO from Peking Union Medical College Hospital were retrospectively analyzed,along with literatures review. Results Totally 23 cases(11 males and 12 females)were enrolled.The median age was 31 years(13-56 years).The most common pathological type was hyaline-vascular variant(91.4%),and most tumors located in abdominopelvic cavity(69.6%).Considerable cases presented bulky masses(26.3%).Most cases were first diagnosed on presentation with the symtoms of PNP(90.0%).BO was characterized by progressive dyspnea after excision of CD lesions.The average follow-up duration was 27.5 months(1-135 months).The median overall survival time was 36.0 months(95% CI=13.9-58.1).Respiratory failure was the dominant cause of death(91.7%).Conclusions PNP should be considered among those patients with specific oral or cutaneous lesions.Earlier diagnosis and treatment of latent UCD are important for reducing complications and deaths.目的 探讨合并副肿瘤天疱疮及闭塞性细支气管炎的单中心型Castleman病的临床特点,以提高临床医师对此类疾病的认识。方法 汇总分析北京协和医院收治及文献报道的同时合并副肿瘤天疱疮及闭塞性细支气管炎的单中心型Castleman病病例的临床资料、治疗及生存转归数据。结果 共纳入23例患者,男∶女=11∶12,中位年龄31岁(13~56岁)。单中心型Castlman病的病理类型以透明血管型为主(91.4%),病灶部位以腹盆腔病灶多见(69.6%),26.3%表现为巨块型病灶。患者多以副肿瘤天疱疮症状首诊(90.0%),多在Castleman病手术后逐渐出现闭塞性细支气管炎表现。平均随访时间为27.5个月(1~135个月),患者的中位总生存时间为36.0个月。闭塞性支气管炎所致的呼吸衰竭是主要死亡原因(91.7%)。结论 重视副肿瘤天疱疮症状的早期识别、积极寻找并治疗潜在的Castleman病,有利于避免并发症的出现和死亡。.

A semi-interpenetrating network hydrogel with pore structure (P-S-IPN) was prepared by solution polymerization with 4-acetyl acryloyl ethyl acetate (AAEA) and crylic acid (AA) as monomers, polyvinylpyrrolidone (PVP) as the second network and polyving akohol 2000(PEG2000) as a pore-foaming agent. Gold nanoparticle composite hydrogel (GNPs gel) was obtained through in-situ reduction reaction by using P-S-IPN as a template. P-S-IPN exhibits excellent mechanical strength, the maximum compressive strength is 14.0 Mpa. The influence of the dosage of PEG2000 on the swelling/deswelling properties of P-S-IPN and GNPs gel was investigated. The pore structures could shorten the time that P-S-IPN takes to reach swelling equilibrium from 170min to 75min, improve the ability of P-S-IPN to absorb AuCl4-. The swelling/deswelling properties of GNPs gel under an applied voltage showed when the concentration of NaCl solutions exceed 0.025mol/L, the hydrogel swells, when the concentration of NaCl solutions is below 0.025mol/L, it deswells.

In order to extract tea polyphenols (TPs) by water under room temperature, the mechanochemical methodology was used for leaching process, and then TPs was purified from leaching solution by ethanol and ammonium sulfate aqueous two-phase system. The optimum parameters of mechanochemical methodology leaching TPs were determined by response surface methodology (RSM), which optimum parameters were: Na2CO3content 25~27wt%, solid material particle size D9540~45μm, liquid/solid mass ratio55~60, leaching time 16~18min. The TPs leaching rate was 16.46%. When ammonium sulfate mass composition0.2, ethanol mass composition0.35 as the composite of the extraction system, TPs maximum extraction rate was 93.4%. The maximum yield of TPs was 15.25% on the average, with average purity was 96.54% ultimately. Under such technology, water is only solvent used in TPs leaching at room temperature, and aqueous two-phase system extraction system under mild conditions, avoid the use of toxic solvent, is a green technology for extracting TPs.

P(DMAA-co-AM)hydrogel; adsorption method; a-amylase; Immobilized enzyme. Abstract. P(DMAA-co-AM)hydrogel was prepared by aqueous solution polymerization with N,N-dimethylacrylamide(DMAA) and acrylamide(AM) as monomers.,taking the P(DMAA-co-AM) hydrogel as carrier, a-amylase was immobilized by adsorption method.The investigation of effection of temperature and pH on enzymatic activity exhibites that the optimum temperatures are 50°C for both free and immobilized enzyme,the maximum activity is observed at pH 6.0 for both free and immobized enzyme. The activity of immobilized a-amylase remaines higher 40% at sixth run. Kinetic studies demonstrate that: Km values are 5.15749 and 1.44479 mg/mL for free and immobilized enzyme, Vmax values are 2.56082 and 0.58272 mg/mL min-1 for free and immobilized enzyme.

The effects of ethylene vinyl acetate grafting maleic anhydride (EVA-g-MAH )as a compatilizer on the mechanical properties, compatibility and morphological structure of thermoplastic Polyurethane and poly(vinyl chloride) blends were studied. The blends were prepared and characterized by mechanics properties test, scanning electron microscopy(SEM,)dynamic mechanical properties (DMA) and thermogravimetry(TG) . Mechanical properties indicate that the hardness, tensile strength, breaking elongation of the blends are greatly improved by EVA-g-MAH, when the critical EVA-g-MAH content at about 4 wt%.SEM micrographs reveal that EVA-g-MAH could bring down the diameter of dispersed , change brittle fracture into ductile fracture, and promote adhesion of phase interface. The glass transition temperature change by DMA proves that the addition of the EVA-g-MAH improved the compatibilization of blends. And the results of TG experiment show that EVA-g-MAH greatly improve the thermal stability of the blends.

以2-丙烯酰胺-2-甲基丙磺酸(AMPS)为有机原料,正硅酸乙酯(TEOS)为无机原料,过硫酸钾为引发剂,N, N'-亚甲基双丙烯酰胺为交联剂,通过原位-凝胶水溶液聚合法合成了一系列不同二氧化硅含量和不同聚离子浓度的聚(2-丙烯酰胺-2-甲基丙磺酸)/二氧化硅杂化电场敏感性水凝胶.通过扫描电子显微镜(SEM)表征凝胶的结构,研究水凝胶在去离子水以及氯化钠溶液中的溶胀和消溶胀行为.结果表明,系列凝胶的平衡溶胀度介于224.9至325.6之间,复合凝胶的溶胀速率随TEOS用量的增加而降低;除理想杂化凝胶外,随着聚离子浓度的升高,凝胶在氯化钠溶液中的消溶胀速率逐渐减小.对凝胶的电场敏感性研究表明,当聚离子浓度大于氯化钠溶液浓度时,凝胶进一步溶胀,反之则消溶胀,其中杂化凝胶的再溶胀性能减弱,而消溶胀行为变得更为明显.同时制得的理想杂化凝胶,较纯有机凝胶具有更为理想的力学性能,最大抗压缩强度可达23.4 MPa.

Using N, N′-methylene bisacrylamide as crosslinking agent and potassium peroxydisulfate as initiator, the temperature-sensitive hydrogels were prepared with organic monomer N-isopropylacrylamide (NIPAAm) and acrylic amide and inorganic material ethyl orthosilicate (TEOS). The structure of hybrid hydrogels was represented by scanning electron microscopy and Fourier transform infrared spectroscopy. The volume phase transition temperature (VPTT) of hybrid hydrogels was determined by differential scanning calorimetry thermograms of the swollen hydrogel. The results showed that the VPTT of the hydrogels increased with the increasing of TEOS dosage. When the temperature was lower than VPTT, the hydrogels exhibited excellent temperature sensitivity and kept at a swelling state, but when the temperature was higher than VPTT, the hydrogels deswelled significantly. In addition, the compressive strength of hydrogels was studied, the results showed that hybrid hydrogels had more ideal mechanical properties than organic hydrogels. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Polyacrylamide and poly(2-acrylamido-2-methyl propyl sulfonic acid) co-polymer[short as P(AM-co-AMPS)] superabsorbent materials were synthesized using 2-acrylamido-2-methyl propyl sulfonic acid and acrylamide as monomers, and P(AM-co-AMPS)/SiO2 hybrid superabsorbent materials were prepared using P(AM-co-AMPS) as the organic phase and SiO2 as the inorganic phase. The absorbent properties of these two kinds of superabsorbent materials were investigated. Fourier-transform infrared (FT-IR) and scanning electron microscopes (SEM) were used to characterize these two kinds of superabsorbent materials. The result shows that the SiO2 can disperse in P(AM-co-AMPS) polymer networks homogeneously. The water-absorbent ability of P(AM-co-AMPS)/SiO2 and P(AM-co-AMPS) is similar, but P(AM-co-AMPS)/SiO2 exhibits better acid, base, salt, organic solvents, and temperature tolerance than the P(AM-co-AMPS) dose. In addition, the swelling speed of P(AM-co-AMPS)/SiO2 is larger than that of P(AM-co-AMPS).

A modified seed-mediated growth method was developed for in situ controllable preparation of gold nanoparticles (GNPs) within P(AMPS-co-HEMA) hydrogel networks. When the time of cycles absorbing procedure increased in mother solutions under given temperature during the processing stage, the number of GNPs was significantly increased and networks were utilized for in situ nanoparticles synthesis by reduction of glod ion absorbed. TEM images confirmed that GNPs were between 100 and 200 nm in size and distributed uniformly in gel. The network embedded GNPs also endows the composite gel with selective catalytic activity for selective catalysis in the reduction of nitro compound (2-NP, 3-NP and 4-NP). The kinetics of the reduction reaction were investigated under the same condition, the result showed the GNPs gel system was found to have an excellent catalytic activity and high conversion for 4-NP reduction among nitrophenol homologue, the nitrophenol hydrogenation rate got to 6.63 mol/g min for reducing of 4-NP compared to 3.69 mol/g min, the rate of 2-NP. It was almost zero for 3-NP implying no catalytic activity, even though they were isomeride.

P(AA-co-DMAA) superporous drug-loaded hydrogels containing berberine hydrochloride were prepared by dispersion polymerization in foam system with acrylic acid (AA) and N,N-dimethyl acrylamide (DMAA) as monomers. Then sodium alginate (SA) as the second network was added to the system, and P(AA-co-DMAA)/SA interpenetrating polymer network (IPN) hydrogels were formed. The effects of pH value, reaction time between SA and glutaric dialdehyde (GA), the concentration of SA and GA on release behavior of berberine hydrochloride were discussed. The FT-IR spectra showed that P(AA-co-DMAA)/SA IPN hydrogels were synthesized successfully. The inverted fluorescence micrograph of P(AA-co-DMAA)/SA showed that some part of the superporous structures were still retained.The cumulative release profiles showed that the release rates were slightly higher in pH=6.8 phosphate buffer solution (PBS) than the one in pH=1 HCl solution. The release rate was the slowest in distilled water, only 7.3% within 24h. When the reaction time between SA and GA was shortened, the release speed of berberine hydrochloride became faster. The pore size of P(AA-co-DMAA) hydrogels was reduced with the concentration of SA and GA increased, and the release rate decreased due to the more dense network structures.

A novel monomer called 4-acetyl acryloyl ethyl acetate (AAEA) was synthesized from acetoacetic ester and acryloyl chloride. Copolymerization was carried out between AAEA and acrylic acid (AA) using azoisobutyronitrile as initiator and N,N′-methylene bis(acrylamide) as crosslinking agent. The novel monomer and the hydrogel were characterized using 1 H NMR and FT-IR. A peak at 17.78 ppm in the 1 H NMR spectra and an absorption band at 1584 cm −1 in the FT-IR spectra of AAEA indicated that AAEA mainly existed as enol forms. In the IR spectra of P(AAEA-co-AA), no peak was observed at around 1600 cm −1 confirmed that copolymerization between AAEA and AA was carried out successfully. The volume phase transition temperature (VPTT) of the hydrogels was determined by their respective DSC thermograms of swollen hydrogel specimens. The results showed that the VPTT of the hydrogels ranged from 50.3 to 61.8 °C, and increased significantly with the increasing dosage of AA. These series of hydrogels exhibited good thermo-sensitivity. When the temperature was higher than the critical temperature, the hydrogels deswelled significantly. Moreover, the critical temperature of the hydrogels increased significantly with the increasing dosage of AA. The pH sensitivity of the hydrogels was also studied. The results indicated that the hydrogels exhibited a discontinuous volume change at around pH = 9.5.

Interpenetrating polymer networks (IPN) hydrogels composed of poly(vinyl acohol) (PVA) and poly(acrylic acid-co-2-acrylamido-2-methyl propyl sulfonic acid) (P(AA/AMPS)) were synthesized by solution polymerization. The IPN hydrogels were characterized using Fourier-transform infrared (FT-IR) and X-ray diffraction (XRD). The results indicated that strong hydrogen bond was formed between PVA and P(AA/AMPS), and the crystallinity of PVA in IPN hydrogels was declined significantly. The swelling/deswelling properties of IPN hydrogel in aqueous Na 2 SO 4 solution were studied. When a sheet of water swollen IPN hydrogel (all the samples were swollen in deionized water) was placed in aqueous Na 2 SO 4 solution, the IPN hydrogel shrunk. However, if a voltage was applied, the IPN hydrogel shrunk at high concentration of Na 2 SO 4 solution, but swelled at low concentration. The results show that the critical concentration of Na 2 SO 4 solution is about 0.005 mol/L. The stimuli response of the IPN hydrogel in electric field was also investigated. When water swollen samples were placed between a pair of electrodes in aqueous Na 2 SO 4 solution, the IPN hydrogel showed significant bending behavior upon the application of an electric field. The bending direction of the IPN hydrogel depends on the concentration of Na 2 SO 4 solution. At high concentration the IPN hydrogel bended toward anode, contrarily, at low concentration the IPN hydrogel bended toward cathode. The critical concentration of Na 2 SO 4 solution is also about 0.005 mol/L. Further investigation showed that the gel component, concentration of aqueous Na 2 SO 4 solution and the applied voltage influenced the bending speed of IPN hydrogel.

To compare the imaging characteristics of magnetic resonance (MR) delayed enhancement between ischemic and nonischemic myocardial diseases.We retrospectively analyzed the imaging and clinical characteristics of 25 patients who had MR delayed enhancement.Among the 25 cases, 19 cases were ischemic heart diseases, in which the delayed enhancement was subendocardium, non-transmural or transmural; two cases were hypertrophic cardiomyopathy, in which the delayed enhancement was midwall in the hypertrophic myocardium, strip- and patch-shaped; one case was dilated cardiomyopathy, in which the delayed enhancement was diffuse small midwall spots two cases was restrictive cardiomyopathy, in which the delayed enhancement was located in the area of the subendocardium both of the right and left ventricles; and one case was a mass of the lateral wall of the left ventricle, in which the delayed enhancement with a clumpy shape was shown.MR myocardial delayed enhancement is not a specific sign of myocardial infarction of ischeminc heart disease. The differentiation of the etiology of the delayed enhancement relies upon both the MR images and the clinical history.

To explore the imaging and related clinical characteristics of magnetic resonance (MR) delayed enhancement in patients with ischemic or nonischemic heart disease.Thirty-two cases who underwent MR myocardial cine and delayed enhancement imaging from January 2004 to October 2006 were retrospectively analyzed. The cine sequence imaging included the four-chamber view and the left ventricular short axis view. The delayed enhancement imaging was taken 10 minutes after the infusion of gadolinium from the antecubital vein with a segmented inversion-recovery-prepared T1-weighted fast gradient echo sequence. Patients underwent coronary computed tomography angiography (CTA) two weeks before or after the MR imaging examination. Combined with clinical history, the clinical and MR imaging characteristics of the patients who had delayed enhancement were analyzed.MR delayed enhancement could be found in 16 cases. Among them, 12 cases had ischemic heart disease. Their coronary CTA showed one to three vessel diseases. The delayed enhancement was transmural or subendocardium, and the area of delayed enhancement corresponded well with one or more coronary arteries which had severe stenosis or occlusion. Four cases had nonischemic heart diseases. One case was dilated cardiomyopathy, with diffuse small midwall spots in delayed enhancemen and only 30% stenosis of the anterior descending coronary artery in coronary CTA. One case was hypertrophic cardiomyopathy, with delayed enhancement of strip- and patch-shaped at midwall of the hypertrophic myocardium. One case was restrictive cardiomyopathy, and the delayed enhancement was located in the area of subendocardium of both the right and left ventricles. Coronary CTA of these two cases were normal. The other case was a mass of the lateral wall of the left ventricle, and the delayed enhancement with a clumpy shape was located in the lateral wall of the left ventricle.MR myocardial delayed enhancement is not a specific sign of myocardial infarction of ischemic heart disease. Nonischemic heart diseases including all kinds of primary cardiomyopathy and some other diseases affecting myocardium can also cause delayed enhancement, but their characteristics are different. The differentiation of the etiology of the nonischemic heart disease with delayed enhancement relies upon the intimate connection with clinical history and the cine sequence MR images.

To evaluate the clinical value of assessment of coronary stent patency by 64-slice spiral CT coronary angiography.Totally 29 patients (59 stents) were investigated using a retrospective ECG-gated enhanced scan by 64-slice spiral CT at a mean interval of (28.4 +/- 21.2) months after coronary stent implantation. Axial multi-planar reconstruction (MPR) of the stents and curved-planar reconstruction (CPR) through the stents were evaluated for image quality on a 5-point scale (1 = excellent, 5 = uninterpretable) and lumen diameter. Stent lumen diameter was compared with the vessel diameter proximal of the stents to assess the in-stent lumen visibility. Conventional coronary angiography was performed in 5 patients, and 9 stents were evaluated.The image quality was good to excellent on average (scores: 1.94 +/- 0.84), depending on heart rate, breath movement, and stent location. Stent lumen was visible, on average a percentage off (76.1 +/- 11.1)% of the lumen diameter. All the 9 stents were correctly detected as being patent, which was confirmed by conventional coronary angiography.64-slice spiral CT is a useful tool to assess the coronary stent patency.

To compare the coronary artery bypass graft (CABG) imaging between 16-slice spiral CT and 64-slice spiral CT.Totally 27 patients with CABG received multi-slice spiral CT imaging and the results were retrospectively analyzed. Among them, 8 patients received 16-slice spiral CT scanning, 19 patients received 64-slice spiral CT scanning.The evaluability rates of 64-slice spiral CT in evaluating the proximal anastomosis, bypass graft, distal anastomosis, and distal blood vessel were 100%, 100%, 90.2%, and 93.9%, respectively, while those of 16-slice spiral CT were 92.3%, 95.2%, 90.0%, and 90.0%, respectively. The patency rates of the above four aspects of 64-slice spiral CT were 66.7%, 70.0%, 71.7%, and 70.0%, respectively, while those of 16-slice spiral CT were 83.3%, 85.0%, 83.3%, and 88.9% .64-slice spiral CT is superior to 16-slice spiral CT in CABG imaging. It can be used as a non-invasive tool for the post-operative follow-up of CABG.

To compare the image quality and visibility of arteries of 64-slice spiral coronary CT angiography (CTA) with those of 16-slice spiral coronary CTA, and to evaluate the diagnostic accuracy of 64-slice spiral CT for the assessment of coronary artery stenosis.Totally 100 patients (Group A) with suspected coronary artery diseases (CAD) were examined by 64-slice spiral CT, 48 of whom also underwent conventional coronary angiography (CAG). Another 100 patients (Group B) with suspected CAD were studied by 16-slice spiral CT. Patients with a heart rate above 70 bpm received oral beta-blockers before the scan. Data were retrospectively analyzed and reviewed by two observers. Image quality was assessed by using a 3-point grading scale from excellent (1) to non-assessable (3) and the rate of displayed coronary branches was calculated. The left main artery (LM), left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA) were screened for the presence of over 50% stenosis.The mean heart rates of two groups showed no significant difference [(61 +/- 8) bpm vs. (61 +/- 7) bpm, P0.05]. The mean scan time of Group A was significantly shorter than that of Group B [(11.9 +/- 0.9) s vs. (22.2 +/- 1.1) s, P0.01]. In the evaluation of image quality, better results were obtained in Group A than in Group B (1.20 +/- 0.47 vs. 1.37 +/- 0. 63, P0.05). The visibility of proximal arteries was similar between two groups, while the visibility of some distal arteries and small branches was found higher in Group A than in Group B (LAD distal 92% vs. 48%, CX distal 98% vs. 89%, the first obtuse marginal (OMI) 93% vs. 84%, cone branch (CB) 86% vs. 71%, P0.05). Compared with CAG, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 64-slice spiral coronary CTA to identify over 50% stenosis were 94.9% (56/59), 93.2% (124/133), 86.2% (56/65), and 97.6% (124/127), respectively.With higher temporal and spatial resolution, 64-slice spiral CT provides improved image quality and visibility of small branches as compared with 16-slice spiral CT. 64-slice spiral coronary CTA allows reliable non-invasive diagnosis of obvious coronary artery stenosis.

To evaluate the value of 16-slice spiral CT in the demonstration of coronary artery and in the diagnose of coronary artery stenosis.Plain and enhanced CT scans were performed with a 16-slice CT scanner (Sensation 16, Siemens, Germany) in 230 patients with suspected coronary heart disease (CHD). Parameters of the plain scan were: 120 kV, 133 mA, slice collimation 16 mm x 1.5 mm, rotation time 0.42 seconds, increment 1.5 mm, and slice width 3 mm. Parameters of the enhanced scan were: 120 kV, 500 mA, slice collimation 16 mm x 0.75 mm, rotation time 0.42 seconds, increment 0.5 mm, and slice width 1 mm. Enhanced CT scan was performed with a rapid intravenous injection of 100 mL iothalamate meglumine (Ultravist) (370 mgI/mL) or Omnipaque (350 mgI/mL) and 30 mL 0.9% NaCl chaser bolus at a flow rate of 3.5 mL/s. Calcium scoring with plain scan images and two and three dimensional reconstruction with enhanced scan images were made in all cases, among which 30 cases underwent conventional coronary angiography. Demonstration of coronary arteries and their stenosis were evaluated and the factors that might influence the image quality were analyzed.Coronary calcium scores were calculated and coronary artery was demonstrated in our study. In the evaluation of image quality with volume rendering technique (VRT) images, 78.3% of the images were of the first class, 12.2% the second class, and 9.6% the third class. Multi-planar reconstruction (MPR) and maximal intensity projection (MIP) were better than VRT in the demonstration of small branches. The image quality was related to the heart rate, with or without arrhythmia, and breath-hold ability of patients. Comparative study of the stenosis of coronary arteries in 30 cases showed that the sensitivity and specificity of 16-slice coronary CT angiography (CTA) to diagnose significant stenosis were 95.8% and 94.8% respectively.As a non-invasive and quick method, 16-slice coronary CTA is sensitive and specific to diagnose the stenosis of coronary arteries and can be used as a screening method in the diagnosis of CHD.

To evaluate the scanning technique and primary clinical value of sixteen-slice spiral CT coronary angiography.Plain and enhanced sixteen-slice spiral CT imaging was performed in 69 patients, including 64 cases of suspected coronary heart disease and 5 cases of coronary stent. Calcium scoring with plain scan images and MPR, MIP and VRT reconstruction with enhanced scan images were made in all cases, among which 10 underwent conventional coronary angiography. The demonstration and stenosis of coronary arteries were evaluated. The factors influencing the image quality were analyzed. Additional MPR and MIP reconstruction of slices perpendicular to the stent and virtual endoscopy of stent were made in 7 stents of the 5 cases of coronary stent. The patency of the stents was evaluated.A four-step scanning procedure was devised. Coronary calcium score could be got by plain scanning with sixteen-slice spiral CT angiography. All of the primary, most of the secondary and tertiary, and part of the fourth level branches of coronary artery could be shown isotropically with MPR, MIP and VRT reconstruction images of enhanced scanning. MPR and MIP were better than VRT in demonstrating small branches. Evaluated by VRT image, the image quality of 79.7% of the patients were first class, 10.1% second class, and 10.1% third class. The image quality was correlated to the contrast concentration in the root of aorta, heart rate, existence or absence of arrythmia, and the patient's breath-holding ability. Stenosis of coronary arteries was evaluated by sixteen-slice spiral CT imaging in 10 cases, with a result comparable to that by conventional coronary angiography. The stents were well shown, six stents being evaluated as patent, while one not.Sixteen-slice spiral CT coronary angiography is a noninvasive, simple and good method. Coronary calcium score and coronary artery stenosis can be evaluated with one study. The patency of stents can also be evaluated.