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51.
From 100 cases of gastroenteritis among children caused by adenovirus infection in Ontario, 33 virus isolates were divided into three categories according to their biological behavior in tissue cultures. So far, the results of neutralization tests, structural protein analysis, and DNA restriction patterns showed that the virus of category 1 was similar to adenovirus type 40. However, the adenovirus of category 2 was a distinct adenovirus which shared some similarities with adenovirus type 5. Viruses of category 3 are still under investigation.  相似文献   
52.
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension.  相似文献   
53.
We used nucleic-acid hybridization and enzymatic and immunofluorescence assay to examine the relatedness of human and animal strains of antigenically distinct rotaviruses (ADRVs). ADRVs isolated from rats and humans in Baltimore, Maryland, were shown to be closely related to bovine and porcine strains of group B rotavirus. A human group B rotavirus associated with epidemics of gastroenteritis in China was also found to share antigenic determinants and genome sequence homology with ADRVs passaged in rats in the United States. Closely related strains of group B rotavirus thus appear to infect human and animal populations in widely separated geographic areas.  相似文献   
54.
Composites are increasing in popularity as restorative materials. This growing role indicates the necessity of studies on their clinical outcome. In this study, clinical studies published on the performance of posterior composite restorations were included except those of less than a 24‐month assessment period. Results of non‐vital, anterior or primary teeth and cervical single‐surface restorations were also excluded. Records about composite type, number of final recall restorations, failure/survival rate, assessment period and failure reasons were analysed for each decade. Overall survival/failure rates for studies in 1995–2005 were 89.41%/10.59% and for 2006–2016 were 86.87%/13.13%, respectively. In 1995–2005, the reasons for failure were secondary caries (29.47%) and composite fracture (28.84%) with low tooth fracture (3.45%) compared with reasons of failure in 2006–2016, which were secondary caries (25.68%), composite fracture (39.07%), and tooth fracture (23.76%). An increase in incidence of composite fracture, tooth fracture and need for endodontic treatment as failure reasons was noted in the latter decade in addition to a decrease in secondary caries, postoperative sensitivity, unsatisfactory marginal adaptation and wear. The overall rates of failure showed little difference, but the causes showed a notable change. This is believed to be a reflection of increased use of composites for larger restorations and possibly changes of material characteristics.  相似文献   
55.
我非常高兴向大家推荐这份发展中国家幽门螺杆菌(H.priori)临床指南。该指南的编译是由数位在该领域具有丰富临床经验的世界知名专家共同完成的。  相似文献   
56.
Enteric pathogens associated with diarrhea were studied for two years at a diarrhea treatment center in rural Bangladesh. Enterotoxigenic Escherichia coli (ETEC) was the most frequently identified pathogen for patients of all ages. Rotavirus and ETEC were isolated from approximately 50% and approximately 25%, respectively, of patients less than two years of age. A bacterial or viral pathogen was identified for 70% of these young children and for 56% of all patients with diarrhea. Most ETEC isolates were obtained in the hot dry months of March and April and the hot wet months of August and September. Rotavirus identification peaked in the cool dry months of December and January, but infected patients were found year-round. The low case-fatality rates for patients with watery diarrhea and substantial dehydration further document the usefulness of treating patients with diarrhea with either a glucose- or sucrose-base electrolyte solution such as those used in this treatment center.  相似文献   
57.
Bersudsky Y, Applebaum J, Gaiduk Y, Sharony L, Mishory A, Podberezsky A, Agam G, Belmaker RH. Valnoctamide as a valproate substitute with low teratogenic potential in mania: a double‐blind, controlled, add‐on clinical trial.
Bipolar Disord 2010: 12: 376–382. © 2010 The Authors. Journal compilation © 2010 John Wiley & Sons A/S. Objectives: Valproic acid’s well‐known teratogenicity limits its use in women of childbearing age. Valnoctamide is an analog of valproate that does not undergo biotransformation to the corresponding free acid. In mice, valnoctamide has been shown to be distinctly less teratogenic than valproate. Valnoctamide is an anticonvulsant, and we hypothesized that valnoctamide is antimanic. Methods: We performed a double‐blind, five‐week, add‐on, controlled trial of valnoctamide in mania. Patients were treated with risperidone at doses of the physician’s discretion. Valnoctamide or placebo was begun at doses of 600 mg/day and increased to 1200 mg after four days. Weekly ratings by a psychiatrist blind to the study drug were conducted using the Brief Psychiatric Rating Scale (BPRS), the Young Mania Rating Scale (YMRS), and the Clinical Global Impression (CGI). Results: Fifteen valnoctamide patients and 17 placebo patients completed at least one post‐baseline week and were included in data analysis. In all efficacy measures valnoctamide was more effective than placebo as an add‐on to risperidone, using two‐way analysis of variance (ANOVA) with time as the within‐subject factor. Two‐way ANOVA showed a significant effect of time (p < 0.001) and significant interaction between treatment and time (YMRS: p = 0.012; BPRS: p = 0.007; CGI: p = 0.003). Differences between valnoctamide and placebo were significant from week 3 to week 5. Conclusion: Valnoctamide could be an important valproate substitute for women of childbearing age with bipolar disorder who may become pregnant.  相似文献   
58.
59.
目的:骨髓基质干细胞移植到心肌梗死的瘢痕心肌组织中可以改善心功能,但以心电图为观察指标的研究不多。实验观察骨髓基质干细胞移植对正常和心肌梗死大鼠心电图及心功能的影响。方法:实验于2004-01/2005-03在哈尔滨医科大学完成。①实验动物:选取4周龄雄性Wistar大鼠80只,随机数字表法分为梗死移植组、正常移植组、梗死非移植组、正常非移植组,20只/组。另选取7d龄Wistar雄鼠30只作为骨髓基质干细胞的来源。②实验方法:采用密度梯度离心法获取鼠骨髓基质干细胞,配成1×109L-1的细胞悬液,使用5-氮胞苷体外诱导培养3~4周,移植前24~48h行Brdu标记。取载有细胞的盖玻片,测定钙释放时将20mmol/L的caffeine快速加在细胞表面。梗死移植组、梗死非移植组大鼠建立心肌梗死模型。造模4周后,梗死移植组将0.25mL诱导的骨髓基质干细胞悬液注射至大鼠心肌梗死后的瘢痕组织,正常移植组同法将骨髓基质干细胞悬液注射至正常心肌组织,梗死非移植组、正常非移植组注射等量不含骨髓基质干细胞的培养液基质。③实验评估:观察骨髓基质干细胞的诱导分化情况及其植入后在瘢痕心肌组织中的生存状态。测定细胞内钙离子浓度。记录术前、冠脉结扎后即刻/细胞移植即刻、术后4周的心电图变化。检测术后4周的超声和血流动力学指标变化。结果:80只大鼠均进入结果分析。①骨髓基质干细胞的诱导分化及其植入后的生存状态:5-氮胞苷诱导3周后,骨髓基质干细胞表达肌钙蛋白Ⅰ和肌凝蛋白重链,细胞内有丰富的肌丝和Z线,细胞器较多。植入4周后在心肌瘢痕组织中分化为心肌细胞。②细胞内钙离子浓度:两组细胞在caffeine刺激下钙离子的释放均呈波峰状,但诱导组应用caffeine后钙离子浓度降低且低于基础状态,钙释放受到抑制,未诱导组不受影响。③心电图观察:与术前比较,梗死移植组QRS波变窄,R波降支出现正常顿挫波,未见显著心律失常。④超声检测及血流动力学分析:术后4周,与梗死非移植组比较,梗死移植组左室收缩末压、左室射血分数和压力变化速率最大值均显著升高(P<0.05或0.01)。结论:骨髓基质干细胞体外诱导后能分化为心肌样细胞,植入到瘢痕心肌组织中生存、增殖良好,可改善心电图及心肌弹性,从而改善心肌梗死大鼠的心功能。  相似文献   
60.
生物软组织可视为具有多层次结构的织构复合水凝胶体系(TCHS)、以水凝胶复合元件(HCE)为基本的构件(CP),通过一定的组合、排列方式构筑一系列多层次结构的不同软组织。软组织中任何层次的结构单元既可视为织构复合水凝胶体系又可视为构件。任何层次的TCHS中,构件的结构及其组合排列方式决定着该层次单元的功能。以织构复合水凝胶体系的观点考察了真核细胞、角膜和骨骼肌的多层次结构。双层网络水凝胶、皮芯复合水凝胶纤维人工肌肉模型、时空匹配可降解细胞支架等研究成果初步地证明了提出织构复合水凝胶体系观点的合理性。  相似文献   
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