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71.
江汉平原鼠间流行性出血热感染研究   总被引:4,自引:0,他引:4  
为了解湖北省江汉平原流行性出血热(EHF)疫区鼠间感染状况,采用挖洞法捕鼠,鉴定鼠种、性别和年龄,检查有无皮肤破伤,检测EHFV抗原抗体。结果,黑线姬鼠和褐家鼠占所捕鼠的69.7%和23.6%,其EHFV感染率分别为21.8%和30.9%。鼠间EHFV感染,成年鼠显著高于亚成年鼠和幼年鼠,感染率分别为40.8%、17.0%和12.4%;皮肤破伤鼠感染率45.9%,显著高于非皮肤破伤鼠的13.9%。感染鼠以窝为单位具有明显的窝聚集性,而感染鼠窝在地理空间上则随机分布。感染鼠血清分型,黑线姬鼠以野鼠型为主,少数为未定型;褐家鼠以家鼠型为主,亦有少数未定型。这表明,江汉平原EHF疫区是以黑线姬鼠和褐家鼠为主要宿主动物的家野混合型疫区;年龄、皮肤破伤和密切接触是该疫区鼠间EHFV传播的重要因素。  相似文献   
72.
脐带夹对防止脐部感染和出血的临床与实验研究   总被引:2,自引:0,他引:2  
目的应用国产脐带夹用于农村山区破伤风高发区,并经离体试验验证其可靠性。方法经湖南、江西、广西等省基层接生员临床应用、并与当地同期或前一年未用夹者进行对照;同时经离体脐带用脐带夹、气门芯或纱线结扎阻断血管后进行金黄色葡萄球菌和破伤风毒素通透试验以及测试承受气压程度试验。结果1年临床使用2296例中,无1例发生破伤风和败血症。可靠性试验结果证明,粗纱线结扎最差,气门芯虽优于前者,但不如脐带夹。结论该脐带夹由于夹持力持久有力,细菌、毒素难以通过、安全可靠,因此能降低新生儿“病从脐入”的发病率和死亡率,有利干优生优育的贯彻.这是一项花费少、收效大的简而易行的适宜技术,值得推广。  相似文献   
73.
Summary The authors describe three cases of systemic lupus erythematosus (SLE) associated with Kikuchi's histiocitic necrotizing lymphadenitis (HNL). Two patients presented a cytomegalovirus infection concomitantly with Kikuchi's lymphadenitis; in one of them the onsets of SLE and HNL were simultaneous. In the third case an inguinal HNL was concomitant with vaginitis of unknown aetiology.  相似文献   
74.
Endothelial selectins are crucial for the recruitment of leukocytes into sites of inflammation. On T cells, ligands for selectins become induced upon differentiation into the effector/memory stage. Initial in vitro studies suggested a correlation between the Th1 phenotype and ligand expression, but whether this also holds true in vivo remained uncertain. We here analyzed selectin ligands on CD4+ T cells producing IFN-gamma, IL-4 or IL-10, prototypic cytokines of the Th1, Th2 and Tr1 subset, respectively. We analyzed mice infected with influenza virus, the bacterium Listeria, and the parasites Toxoplasma (all Th1 models) or Nippostrongylus (Th2 model). A link between the Th1 phenotype and ligand expression was not found in vivo. Surprisingly, the potentially regulatory IL-10-producing T cells displayed the highest frequency of ligand-positive cells in general. Within the inflamed tissues, the frequencies of P-selectin-binding cells increased in the dominant subset, either Th1 or Th2. Up-regulation was also found for E-selectin ligands during influenza, but not Nippostrongylus infection. In conclusion, conditions driving T cell polarization into either Th1 or Th2 in vivo do not affect the expression of selectin ligands, but acquisition of P-selectin binding and hence migration into inflamed tissues is boosted by an inflammatory milieu.  相似文献   
75.
本实验采用大鼠40%Ⅲ°烫伤模型,初步观察了选择性肠道清洁法(SDD)对肠源性内毒素血症的防治效果。结果发现,防治组动物门、体循环内毒素水平伤后均显著降低(P<0.05~0.01),各段肠腔内游离内毒素含量较烫伤对照组下降99.5%以上。且肠道细菌易位率致伤1~5天都明显减少,回肠粘膜二胺氧化酶活性逐渐恢复。防治组大鼠严重烫伤5天存活率提高26.7%(P<0.05)。本结果提示,该方法对于重症烫伤大鼠肠源性内毒素血症具有显著防护效应,并能抑制肠道细菌的移居与减轻肠粘膜的进一步损害。因此,及早进行SDD可能有助于烧伤后肠源性感染及其它并发症的防治。  相似文献   
76.
Lack of efficient culture systems for hepatitis C virus (HCV) has been a major obstacle in HCV research. Human liver cells grown in a three-dimensional radial-flow bioreactor were successfully infected following inoculation with plasma from an HCV carrier. Subsequent detection of increased HCV RNA suggested viral replication. Furthermore, transfection of HCV RNA transcribed from full-length cDNA also resulted in the production and release of HCV virions into supernatant. Infectivity was shown by successful secondary passage to a new culture. Introduction of mutations in RNA helicase and polymerase regions of HCV cDNA abolished virus replication, indicating that reverse genetics of this system is possible. The ability to replicate and detect the extracellular release of HCV might provide clues with regard to the persistent nature of HCV infection. It will also accelerate research into the pathogenicity of HCV, as well as the development of prophylactic agents and new therapy.  相似文献   
77.
张英  闻良珍 《中国优生与遗传杂志》2005,13(10):19-20,33,F0003
目的探讨巨细胞病毒感染致中枢神经系统功能紊乱的神经生物学机制.方法将BALB/C乳鼠同母鼠随机分为实验对照组(18只)和接种病毒组(35只),感染方法为颅内注射,3个月后检测两组鼠的行为学变化及脑皮质CaMmRNA表达的改变.结果接种病毒组小鼠学习记忆能力下降,皮质CaMmRNA表达增加(1.0493±0.32,P<0.01).结论巨细胞病毒感染所引起的脑皮质CaMmRNA表达增高可能是其神经系统发育异常的神经生物学机制之一.  相似文献   
78.
This report details the fine-needle aspiration biopsy (FNAB) cytomorphologic features of two cases of salivary gland mycosis. Both patients had acquired immunodeficiency syndrome (AIDS) and presented with parotid gland masses. The first patient had Histoplasmosis with secondary infection by Candida. Cytopathologically, the FNAB smears showed classic features of a deep-seated mycosis characterized by necrosis and scattered fungal forms. The second patient had a colonizing sialadenitis caused by either Asperigillus or Fusarium. Cytopathologically, the findings were similar to those seen in aspergillomas of the lung orparanasal sinuses with numerous hyphal forms and an absence of an inflammatory response. Because mycotic disease can induce a wide spectrum of pathogenic change, other benign or malignant, solid or cystic lesions enter into the differential diagnosis. Diagn Cytopathol 1994; 11:286–290. © 1994 Wiley-Liss, Inc.  相似文献   
79.
目的探讨噬菌体治疗耐药性铜绿假单胞菌感染的疗效.方法以BALB/c小鼠为实验动物,建立耐药性铜绿假单胞菌全身感染模型,应用体外试验所筛选的宽噬噬菌体进行治疗.结果噬菌体在感染复数(multiple of infection,MOI)≥0.01时能有效杀灭铜绿假单胞菌,显著提高小鼠生存率.延迟治疗3 h仍有40%的生存率.结论通过对小鼠生存率、噬菌体在体内分布及机体对噬菌体的免疫反应等指标的观察分析,噬菌体制剂简捷高效,对机体正常组织无毒副作用,从而为临床治疗全身或局部铜绿假单胞菌感染提供了新途径.  相似文献   
80.
Infradiaphragmatic extralobar pulmonary sequestration is an extremely rare congenital malformation. It is more frequently diagnosed in the antenatal period due to routine ultrasonic examination of the fetus or in the first 6 months of life, though on rare occasions it is discovered incidentally in adults. A 32-yr-old man presenting with epigastric discomfort and fever was referred. Computed tomographic scanning showed that a 16-cm, multiseptated, dumbbell-shaped, huge cystic tumor was located beneath the diaphragm. On the next day, 850 mL of thick yellowish pus was drained by sonography-guided fine needle aspiration for the purpose of infection control and diagnosis, but no microscopic organisms were found in repeated culture studies. Surgical removal of the cyst was performed through thoracoabdominal incision and most of these pathologic lesions were removed but we could not find the feeding arteries or any fistulous tract to surrounding structures. Histopathologic study revealed that it was extralobar pulmonary sequestration and culture study showed that many WBC and necrotic materials were found but there were no microorganisms in the cystic contents. We report the first case of an infected infradiaphragmatic retroperitoneal extralobar sequestration which was administered a staged management and achieved an excellent clinical course.  相似文献   
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