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991.
丙型肝炎病毒感染的血清学检测 总被引:2,自引:0,他引:2
目的了解丙型肝炎病毒(HCV)感染及病毒血症存在情况。方法用酶联免疫吸附试验(ELISA)和聚合酶链反应(PCR)对不同人群的血清标本做了抗-HCV、抗-HCVIgM和HCVRNA的检测,并对三项指标间的关系进行了对比分析。结果抗-HCV在普通成年人、献血员、急性肝炎和肝硬化患者中的检出率分别是357%,858%,625%和4838%;与HCVRNA的符合率分别是1143%,6111%,800%和7333%。相同人群抗-HCVIgM与HCVRNA的符合率分别是75%,909%,8181%和100%。结论抗-HCVIgM比抗-HCV能更客观地反映HCV病毒血症的情况,个别抗-HCV阴性血清检测到了抗-HCVIgM和HCVRNA。 相似文献
992.
Changing seroepidemiology of hepatitis B, C, and D virus infections in high-risk populations 总被引:1,自引:0,他引:1
Huo TI Wu JC Wu SI Chang AL Lin SK Pan CH Huang YH Chang FY Lee SD 《Journal of medical virology》2004,72(1):41-45
Needle-sharing and sexual contact are important transmission routes of hepatitis B, C, and D virus (HBV, HCV, HDV) infection. This study aimed to investigate the current status of these viral infections among high-risk populations including prostitutes and intravenous (i.v.) drug users, compared with the prevalence rate reported previously to examine the changing seroepidemiology. Of the 916 female prostitutes, 79 (9%) were positive for antibody to HCV (anti-HCV), 111 (12%) were positive for HBV surface antigen (HBsAg), and 5 (5%) had antibody to HDV (anti-HDV). The prevalence rate was significantly lower compared to that in 1989-1991 (12%, P = 0.037) for HCV infection, and to that in 1988 (59%) and 1996 (40%) (P < 0.0001) for HDV infection. Of the 494 i.v. drug users, 87 (18%) patients were HBsAg carriers and 12 (14%) were anti-HDV-positive. The prevalence rate of HDV infection was significantly lower than that reported in 1985 (79%, P < 0.0001). Among the 443 tested i.v. drug users, 182 (41%) were anti-HCV-positive, significantly lower than that in 1985 (53%, P = 0.026). Of the 263 male prostitutes, 11 (4%) were anti-HCV-positive, 45 (17%) were HBsAg-positive, and 7 (16%) were anti-HDV-positive. Of the 129 illegal immigrant prostitutes, 7 (5%) were anti-HCV-positive, 15 (12%) were HBsAg-positive and none were positive for anti-HDV. In conclusion, the findings indicate a declining prevalence of HCV and HDV infections among drug users and prostitutes over the past 16 years. Male prostitutes and immigrant prostitutes are new "high-risk" populations and may become a reservoir for disease transmission. 相似文献
993.
Hinckley CA Hartley R Wu L Todd A Ziskind-Conhaim L 《Journal of neurophysiology》2005,93(3):1439-1449
Electrophysiological and morphological properties of genetically identified spinal interneurons were examined to elucidate their possible contribution to locomotor-like rhythmic activity in 1- to 4-day-old mice. In the transgenic mice used in our study, the HB9 promotor controlled the expression of the reporter gene enhanced green fluorescent protein (eGFP), giving rise to GFP+ motoneurons and ventral interneurons. However, only motoneurons and a small group of bipolar, GFP+ interneurons expressed the HB9 protein. The HB9(+)/GFP+ interneurons were clustered close to the medial surface in lamina VIII along segments L1-L3. The correlation between activity pattern in these visually identified interneurons and motoneuron output was examined using simultaneous whole cell and ventral root recordings. Neurochemically induced rhythmic membrane depolarizations in HB9/GFP interneurons were synchronous with ventral root rhythms, indicating that the interneurons received synaptic inputs from rhythm-generating networks. The frequency of excitatory postsynaptic currents significantly increased during ventral root bursts, but there was no change in the frequency of inhibitory postsynaptic currents during the cycle period. These data implied that HB9/GFP interneurons received primarily excitatory inputs from rhythmogenic interneurons. Neurobiotin-filled axon terminals were in close apposition to other neurons in the cluster and to motoneuron dendrites, raising the possibility that HB9/GFP interneurons formed synaptic connections with each other and with motoneurons. The expression of the vesicular glutamate transporter 2 in axon terminals of HB9/GFP interneurons indicated that these were glutamatergic interneurons. Our findings suggest that the visually identified HB9/GFP interneurons are premotor excitatory interneurons and putative constituents of networks generating locomotor rhythms in the mammalian spinal cord. 相似文献
994.
Ching-Yi Cho Yi-Hsuan Tang Yu-Hsuan Chen Szu-Yao Wang Yi-Hsin Yang Ting-Hao Wang Chang-Ching Yeh Keh-Gong Wu Mei-Jy Jeng 《Journal of microbiology, immunology, and infection》2019,52(2):265-272
Background
Group B Streptococcus (GBS) infection is one of the major causes of neonatal morbidity and mortality. Universal GBS screening with intrapartum antibiotic prophylaxis (IAP) in pregnant women were initiated in 2012 in Taiwan. This study aimed to analyze the most recent maternal GBS colonization rate and the changes in neonatal GBS infection rate from 2011 to 2016.Methods
All pregnant women and their live born neonates between January 2011 and June 2016 were retrospectively reviewed. Whether GBS screening was done, screening results, presence of risk factors, the use of antibiotics, and neonatal outcome were analyzed. In addition, hospitalized neonates diagnosed with GBS infections were retrieved for comparison of early onset disease (EOD) (<7 days) and late onset disease (LOD) (≥7 days).Results
A total of 9535 women delivered babies during the study period. The maternal GBS screening rate was 71.0% and the colonization rate was 22.6%. The overall neonatal invasive GBS infection rate was 0.81 per 1000 live births and the vertical transmission rate was 1.2%. After 2012, the invasive neonatal GBS infection rate declined from 1.1–1.6‰ to 0.6–0.7‰ in 2014 and thereafter, the GBS EOD incidence rate declined from 2.8‰ to 0.0–0.6‰, but the LOD incidence rate remained approximately 0.7‰. Infants with EOD had strong association with obstetric risk factors.Conclusions
Taiwan's universal GBS screening with IAP program reduced the incidence rate of neonatal GBS EOD to be lower than 1‰ after 2012. Pediatricians still should pay attention to infants with GBS LOD since its incidence rate remained unchanged. 相似文献995.
Forty-five patients with cnlargement of the pa
rotid or submandibLtlar salivary gland were studied
clinically, histopathologically and histochemically. It
is concluded that there is a kind of salivary gland
enlargement which shows the nature of degenerative
changes. Accordingly, the term "degenerative sia-
losis" is proposed to replace the confusable term
"benign enlargement of salivary gland". 相似文献
996.
器官培养在研究人食管上皮癌变中的应用 总被引:1,自引:1,他引:0
将组织块置于明胶海绵上,摇摆器官培养,4~6周后成人食管粘膜仍保持良好的结构形态,具有活跃生长的上皮细胞和良好的腺体结构;将组织块贴壁,静置外植块—细胞培养,成人食管粘膜和胎儿食管组织块可存活2~3个月,提供大量生长旺盛的上皮细胞。成人食管癌旁粘膜培养利于观察细胞癌前改变,可能较易于诱发癌变;胎儿食管具有正常背景,利于研究细胞癌变的全过程.二者配合可组成研究人食管上皮癌变的完整体外实验系统。 相似文献
997.
吴世盘 《中国现代应用药学》1987,(2)
试验证明,直接荧光诊断法是诊断柑桔黄龙病的一种快速、简便、准确的方法。 将健叶和黄龙病叶叶柄用保险刀片徒手切片,在透射式荧光显微镜下检查,可看到健叶叶柄的木质部导管细胞壁发黄色荧光,韧皮纤维细胞发绿色荧光,而病叶叶柄韧皮部中有1~多个鲜明的黄色或黄绿色荧光团块。这种特异性的荧光,在健叶柄韧皮部中是没有的,其它由病毒、类病毒、细菌、真菌等病原引起的病叶柄韧皮部中亦没有此种特异性荧光。 相似文献
998.
我国正常生育力男子精浆的微量元素研究 总被引:12,自引:5,他引:7
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。 相似文献
999.
Radiologic and manometric correlation in "nutcracker esophagus" 总被引:1,自引:0,他引:1
D J Ott J E Richter W C Wu Y M Chen D W Gelfand D O Castell 《AJR. American journal of roentgenology》1986,147(4):692-695
"Nutcracker esophagus" is a newly described esophageal motor disorder seen in some patients with chest pain and/or dysphagia and characterized manometrically by normal primary peristalsis with distal contractions of high amplitude. The radiographic and manometric examinations in 20 patients with nutcracker esophagus were correlated. Normal primary peristalsis was observed radiographically in 16 patients, and a nonspecific motor disorder was diagnosed in the remaining four patients. Mild-to-severe nonspecific tertiary activity was seen in about half of the patients, esophageal wall thickness was normal. It is concluded that nutcracker esophagus is primarily a manometric diagnosis made in the appropriate clinical setting, and that the radiographic findings are normal or nonspecific. 相似文献
1000.
Wu Shen吴慎 Ju Lian-cai鞠连才 Shao Hui-xun邵惠训Zhang Xi-tan张习坦 Meng Qing-hai孟庆海 andLi Xue-guang李学光 《中华医学杂志(英文版)》1986,99(5):387-392
A strain (named BJ-1) of hepatitis A virus (HAV)
causing cytopathic effects (CPE) has been isolated in
A549 cell cultures from a fecal specimen of an infant
with hepatitis A. Hepatitis A antigen (HAAg) w3s
detectable in about 50To of the cells by immunofluo-
rescence (IF) assay. The viral antigenicity was spe-
cifically identified by monoclonal anti-HAV and chim-
panzee reference antiserum to HAV (NIH). HAV
particles in crystal arraDgement were observed in cell
cytoplasm by electron microscopy in ultrathin sec
tions. The particles appeared both "empty" and
"full". It was observed that many 27-30 nm virtts
particles were aggregated by convalescent human he-
patitis A sera and chimpanzee HAV antisera observ-
ed by immune electron microscopic (IEM) ex-
amination. BJ-1 HAAg could be detected on day
34 after inoculation at the initial passage. The virus
titers increased and the virus replication cycle short-
ened with serial passages. The highest TCID 50
was 10-5/0.1 ml and the shortest replication cycle 2-3
days. IF kit consisting of BJ-1 HAV infected A549
coverslip culture and sheep fluorescence antibody to
human IgM were made to detect anti-HAV IgM.
Comparing the BJ-t IF with the Abbott EIA HAVAB-
M kit. the coincidence rate was 98.4% (246/250). 相似文献