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排序方式: 共有803条查询结果,搜索用时 15 毫秒
1.
人胎盘基因表达谱芯片的初步研究   总被引:5,自引:2,他引:3  
目的:制备人胎盘基因表达谱芯片,并用于基因差异表达分析。方法:用基因芯片点样仪将胎盘基因文库探讨打印在氨基包被的玻片上制备表达谱芯片。分别提取对照组与三氧化二砷处理的K562细胞总RNA,纯化mRNA后反转录成cDNA,再以限制性显示技术进行荧光标记,将两组荧光标记的样品混合后与芯片进行杂交,杂交后清洗芯片,干燥后对芯片进行扫描,分析杂交结果。结果:建立了较可靠的制备与检测基因表达谱芯片的方法,并筛选出45个差异表达基因片段,结论:制备的人胎盘基因表达谱芯片可有效地应用于基因的差异表达分析。  相似文献   
2.
BACKGROUND/PURPOSE: Abdominal nontuberculous mycobacterial infection is a rare condition. Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis is the most common manifestation of infection due to nontuberculous mycobacteria (NTM). There are limited data on the clinical manifestations of nontuberculous mycobacterial infection. This study investigated the diagnostic features, clinical presentation, mycobacteriology, treatment and outcome of all abdominal NTM infections treated over a 7-year period at a major teaching hospital in Taiwan. METHODS: The medical records of all patients with a diagnosis of abdominal NTM infection from January 1997 through to December 2003 were retrospectively reviewed. RESULTS: All 11 patients with abdominal NTM infections identified during the 7-year period were included. Among these patients, six were male and five were female, with a mean age of 64.5 years. The disease manifested as peritonitis (9 patients, 82%), splenic abscess (1, 9%), or perirenal abscess (1, 9%). Most patients (73%) had underlying malignancy, most often hepatoma (45%). Immunocompromised status (liver cirrhosis, malignancy, acquired immunodeficiency syndrome) was noted in 10 patients (91%). None of our patients who developed NTM peritonitis had received CAPD. The peritoneal fluid appearance varied considerably, with no particular predominance of clear, turbid, bloody, or chylous findings. Rapidly growing mycobacteria were the major etiology (46%) of abdominal NTM infection, and Mycobacterium abscessus played a major role (27%). Overall, eight patients died, and only one patient survived longer than 1 year. Seven patients (64%) died before diagnosis. CONCLUSION: Abdominal NTM infection is frequently overlooked because of its rarity and nonspecific symptoms, with consequent delays in diagnosis and treatment. In immunocompromised patients with ascites from any cause (liver cirrhosis, malignant ascites, etc.), NTM peritonitis should be considered early in the differential diagnosis of symptoms including fever, abdominal pain and weight loss. The poor prognosis of abdominal NTM infection appears to be related to the severity of underlying conditions, most often malignancy.  相似文献   
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4.
目的 :描述某乡镇育龄妇女智力缺陷现患率 ,评价智力缺陷对不良妊娠史的危害。方法 :应用成人智残评定量表筛查并经中国修订韦氏成人智力量表 (WAIS-RC)测定智商 ,评定某乡镇 2 0~ 49岁农村智力缺陷妇女 92人 ,其中因脑炎、外伤等疾病所致缺陷 2 0人 ,不明原因智力缺陷妇女 54人。调查智力缺陷妇女现患及其不良妊娠史。结果 :某乡镇智力缺陷育龄妇女检出率为 7.8‰ ,妇女各年龄别智力缺陷检出率差异无显著性 (P=0 .2 0 6) ;轻度智力缺陷妇女占 45.7%。原因不明的智力缺陷母亲可增加子女智力缺陷的风险。结论 :某农村智力缺陷妇女检出率较高 ,为切实提高人口素质应重视农村地区智力缺陷妇女生殖保健工作。  相似文献   
5.
目的:观察3g/L盐酸洛美沙星眼凝胶的临床疗效及安全性。方法:对128例(203眼)细菌性结膜炎和细菌性角膜炎患者采用多中心、随机分组、平行对照试验,观察其主要症状体征消失情况、角膜炎症面积缩小情况、病原菌清除效果和不良反应。试验组(testgroup,TG)65例(103眼),对照组(controlledgroup,CG)63例100眼,分别应用3g/L盐酸洛美沙星眼凝胶和3g/L盐酸洛美沙星滴眼液。结果:①TG治愈率(80.6%)高于CG治愈率(65.0%);②TG(细菌性结膜炎)眼痛异物感消失率和消失时间(83.7%,5.33±2.00d)优于CG(64.1%,6.36±1.50d);TG(细菌性结膜炎)流泪消失率(91.8%)高于CG(75.0%);③记分统计表明:TG(细菌性结膜炎)结膜充血改善(平均下降1.76分)明显优于CG(平均下降1.25分);TG畏光消失情况(平均下降1.24分)好于CG(平均下降0.87分);TG(细菌性结膜炎)分泌物消失情况(平均下降1.64分)好于CG(平均下降1.33分);④其他情况两组间无明显差异。结论:3g/L盐酸洛美沙星眼凝胶治疗眼前段细菌感染安全、有效,对结膜炎症状体征的改善优于滴眼液。  相似文献   
6.
许俐  陈艳  宋丽娜 《中国妇幼保健》2006,21(14):1999-2001
目的:探讨TRAIL联合紫杉醇对卵巢癌3AO细胞株凋亡的影响,以进一步研究其诱导细胞凋亡的原理。方法:应用MTT法检测TRAIL和紫杉醇作用组的抑制率,并以流式细胞仪检测各组凋亡率。结果:亚毒剂量的TRAIL、紫杉醇及联合作用组致卵巢癌3AO细胞凋亡率分别为17.6%、16.1%、64.3%。单独应用组与联合应用组之间存在显著性差异(P<0.01)。结论:TRAIL在诱导卵巢癌细胞凋亡的同时,也显著提高了其对紫杉醇(taxol)的化疗敏感性。  相似文献   
7.
一株黑色素高产细菌的发酵条件研究   总被引:3,自引:0,他引:3  
采用正交试验和单因素试验研究了黑色素高产细菌BFHM2002获得高产所需的发酵条件.结果表明其最适培养基为(%,w/v):蛋白胨2、甘露醇0.4、碳酸钙0.2、氯化钠0.5、L-酪氨酸0.1,pH6.0.在优化条件下,产量可达3.25mg/ml.  相似文献   
8.
Background:This study aimed to analyze and summarize the research hotspots and trends in neuroimaging biomarkers (NMBM) in Parkinson disease (PD) based on the Web of Science core collection database and provide new references for future studies.Methods:Literature regarding NMBM in PD from 1998 to 2022 was analyzed using the Web of Science core collection database. We utilized CiteSpace software (6.1R2) for bibliometric analyses of countries/institutions/authors, keywords, keyword bursts, references, and their clusters.Results:A total of 339 studies were identified with a continually increasing annual trend. The most productive country and collaboration was the United States. The top research hotspot is PD cognitive disorder. NMBM and artificial intelligence medical imaging have been applied in the clinical diagnosis, differential diagnosis, treatment, and prognosis of PD. The trends in this field include research on T1 weighted structure magnetic resonance imaging in accordance with voxel-based morphometry, PD cognitive disorder, and neuroimaging features of Lewy body dementia and Alzheimer disease.Conclusion:The development of NMBM in PD will be effectively promoted by drawing on international research hotspots and cutting-edge technologies, emphasizing international collaboration and institutional cooperation at the national level, and strengthening interdisciplinary research.  相似文献   
9.
Bovine respiratory disease complex (BRDC) is a comprehensive disease in cattle caused by various viral and bacterial infections. Among them, bovine herpesvirus type I (BoHV−1) and bovine viral diarrhea virus (BVDV) play important roles and have caused huge financial losses for the cattle industry worldwide. At present, vaccines against BRDC include trivalent attenuated BoHV−1, BVDV−1, and BVDV−2 live vaccines, BoHV−1 live attenuated vaccines, and BoHV−1/BVDV bivalent live attenuated vaccines, which have limitations in terms of their safety and efficacy. To solve these problems, we optimized the codon of the BVDV−1 E2 gene, added the signal peptide sequence of the BoHV−1 gD gene, expressed double BVDV−1 E2 glycoproteins in tandem at the BoHV−1 gE gene site, and constructed a BoHV−1 genetics-engineered vectored vaccine with gE gene deletion, named BoHV−1 gE/E2−Linker−E2+ and BoHV−1 ΔgE. This study compared the protective effects in BoHV−1, BoHV−1 ΔgE, BoHV−1 gE/E2−Linker−E2+, and BVDV−1 inactivated antigen immunized guinea pigs and calves. The results showed that BoHV−1 gE/E2−Linker−E2+ could successfully induce guinea pigs and calves to produce specific neutralizing antibodies against BVDV−1. In addition, after BoHV−1 and BVDV−1 challenges, BoHV−1 gE/E2−Linker−E2+ can produce a specific neutralizing antibody response against BoHV−1 and BVDV−1 infections. Calves immunized with this type of virus can be distinguished as either vaccinated animals (gE-) or naturally infected animals (gE+). In summary, our data suggest that BoHV−1 gE/E2−Linker−E2+ and BoHV−1 ΔgE have great potential to prevent BVDV−1 or BoHV−1 infection.  相似文献   
10.
目的 探讨肝素结合蛋白(heparin-binding protein,HBP)对儿童重症感染的诊断价值.方法 该研究系前瞻性观察研究.收集2019年1月到2020年1月因感染入住儿童重症监护室患儿的临床资料,按照严重脓毒症与脓毒症诊断标准分为严重脓毒症组(49例)、脓毒症组(82例)和非重症感染组(33例),比较3组...  相似文献   
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