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101.
We correlated MRI features with histopathological findings in an HIV-positive patient with vacuolar myelopathy. On MRI symmetrical nonenhancing high-signal areas in the posterior columns on T2-weighted images result from extensive vacuolation visible on histological sections. Received: 18 November 1997 Accepted: 23 March 1997  相似文献   
102.
为探讨孕妇乙型肝炎病毒(HBV)感染和某些因素对先天性畸形的致病作用,本文进行了96对新生儿先天畸形的配对(1:1)病例对照研究,报道先天畸形的频率和构成,单因素和多因素的条件Logistic回归分析,表明孕妇HBsAg阳性等6个因素对先天畸形呈阴性结果,而与接触农药和孕周的因素有明显联系,值得进一步探讨。  相似文献   
103.
Abstract Human immunodeficiency virus (HIV)-l neuropathogenesis can be divided into three important components: (i) virus entry into the nervous system; (ii) the role of viral proteins and/or cellular products in neural tissue damage; and (iii) the mechanisms of neuronal injury/death. Both blood derived macrophages or trafficking HIV-1 infected T-lymphocytes have been implicated in viral entry to the central nervous system (CNS). The major cell type harboring productive HIV-1 infection in the nervous system is the perivascular macrophage/ microglia. The HIV-1 infection of brain astrocytes, restricted to the expression of regulatory gene products, may cause astrocyte dysfunction and contribute to neuronal injury or to disruption of the blood-brain barrier (BBB). Studies of cerebrospinal fluid and postmortem tissues reveal chronic inflammation/immune activation in the nervous system during the later stages of HIV-1 infection associated with disruption of BBB integrity. Blood-brain barrier damage may underlie the white matter pallor described in HIV-1 infection and could result in further entry into the CNS of toxic viral or cellular products, or additional HIV-1 infected cells. The HIV infected and activated macrophages/microglia produce excessive amounts of pro-inflammatory cytokines, including tumor necrosis factor alpha, and platelet activating factor. These products are directly toxic to human neurons in vitro. The HIV-1 envelope glycoprotein, gp 120 may stimulate the release of toxic factors from brain macrophages. Blocking N-methyl-D-aspartate (NMDA; or AMPA) glutamate receptors can antagonize candidate toxins of both viral and cellular origin. It has been postulated that (weak) excitotoxicity leads to oxidative stress in neurons and ultimately to apoptosis. Neuronal apoptosis occurs in the brains of both children and adults with HIV-1 infection. This understanding of HIV neuropathogenesis implies that therapeutic strategies should include: (i) anti-retroviral medications to decrease systemic and CNS virus load, and possibly to prevent perinatal transmission of HIV; (ii) anti-inflammatory compounds to decrease the chronic immune activation in microglia and allow the restoration of BBB integrity; and (iii) neuroprotective compounds to reduce neuronal injury and apoptotic death.  相似文献   
104.
The clinical findings in 26 patients in whom hepatocellular carcinoma (HCC) was detected after the start of interferon (IFN) therapy for chronic hepatitis C were analysed. Histological study before IFN therapy showed that 34.6% of patients were categorized as stage 3 (septal fibrosis with architectural distortion; the 0–4 scale) and 80.8% demonstrated at least some evidence of septal fibrosis or more advanced features. The AFP levels examined before IFN therapy were more than 20 ng/mL in 13 patients (84.6% of those studied). One of 26 patients had a complete response to IFN therapy, while six of 26 patients had only a partial response. HCC was detected within 1 year after the start of IFN therapy in 76.9% of patients. Thus, the possibility of the early occurrence of HCC or its existence at the time of therapy should be seriously considered when IFN therapy is contemplated. Patients with stage 3 or 3–4 histology may already have a small undetectable HCC before IFN therapy. Thus, for this reason, every patient treated with IFN should be examined at short regular intervals for the development of HCC during and after IFN therapy.  相似文献   
105.
110例嗜酸细胞增多性非变应性鼻炎的液氮冷冻治疗山西医学院第二附属医院(030001)牛玉梅,刘学仁按Mggind将常年性鼻炎分为三类:一类常年性变态反应性鼻炎;二类非变态反应性鼻炎伴鼻分泌物嗜酸细胞增多综合征也叫嗜酸细胞增多性非变态反应性鼻炎(Eosinophilicnonalleraicrhinits,ENR);三类自主神经性常年性鼻炎[1]。我们将ENR中找不到致敏物,而与冷热空气有关与情绪无关的110例患者进行了液氮冷冻治疗。临床资料802例常年性鼻炎患者进行皮肤激发试验。437例找出了致敏物,进行特异性过敏诱因脱敏治疗或抗过敏药物治疗。365例试验阳性,其中有135例与冷热空气有关。ll0例行冷冻治疗。1l0例中男50例,女60例;年龄最大65岁,最小16岁。110例均有间歇性的连续喷嚏发作,浆液性或粘液性鼻分泌物增多和鼻粘膜非充血性肿胀引起的堵塞,无因吸入致敏原诱发症状的病史;血清IgE值不升高,特异性皮肤试验结果为阳性;鼻分泌物中嗜酸细胞阳性。方法:先将鼻腔内喷入1%地卡因溶液3次粘膜表面麻醉,用卷好的4厘米长、0.4~0.6厘米粗的棉棒沾上液氮在鼻镜直视下迅速插入鼻腔内。时间约1分钟左右(冷  相似文献   
106.
目的:通过研究丙型肝炎病毒高变区1(HCV HVR1)准种复杂性与基因型之间的关系,探讨不同基因型HCV致病性差异的机制.方法:采用C区型特异性引物PCR法进行HCV基因分型,采用单链构象多态性聚合酶链反应法(SSCP法)检测HCV HVR1准种.结果:68例丙型肝炎患者中,Ⅱ型49例(72%),Ⅲ型13例(19%),Ⅱ、Ⅲ混合型6例(9%).Ⅱ型和Ⅱ、Ⅲ混合型HCV感染患者的HCV HVR1准种复杂性(SSCP条带数)明显高于Ⅲ型感染的患者,且与疾病严重程度关系密切.结论:HCV HVR1准种复杂性的差异可能是导致不同基因型HCV致病性差异的因素之一.  相似文献   
107.
Background: The Centers for Disease Control and Prevention is incorporating laboratory data into real-time surveillance systems. When normal patterns of laboratory test orders and results are modeled, aberrations can be detected. Because many test orders are available electronically well before results, atypical patterns of test ordering may signal outbreaks.
Objectives: The authors sought to characterize baseline patterns in the ordering and early results of lumbar punctures, motivated by the possibility of using these data for real-time surveillance for early detection of meningitis or encephalitis outbreaks.
Methods: Retrospective cohorts of pediatric emergency department patients at a single hospital (1993–2003) and from the National Hospital and Ambulatory Medical Care Survey (1992–2000) were used for analysis.
Results: Test ordering exhibits seasonal patterns, with monthly peaks in January and August (p < 0.0001). For the hospital cohort, the rate of cerebrospinal fluid pleocytosis exhibits seasonal patterns (p < 0.0001), with a peak from August to October. This is strongly associated with the rate and pattern of clinical neurologic disease (p < 0.0001). A long-term secular decline in daily test ordering is evident, dropping from 5.3 to 2.9 in the hospital sample, and from 371.8 to 185.3 in the national sample (p < 0.001). The long-term rate of pleocytosis has declined (p < 0.0001), though the yield of testing for pleocytosis has improved (p = 0.0104).
Conclusions: Laboratory test patterns correspond with those of clinical disease and are a promising source of surveillance data. Using such data for real-time monitoring requires specific adjustments for patient age, periodicities, and secular trends.  相似文献   
108.
抗戊型肝炎病毒重组蛋白单克隆抗体的制备和初步应用   总被引:4,自引:0,他引:4  
目的:制备抗-戊型肝炎病毒的单克隆抗体,并将其用于分析戊型肝炎病毒不同毒株结构蛋白的抗原表位。方法:采用来自墨西哥株(Mexicanstrain)的戊型肝炎病毒重组蛋白(p166Mex)免疫Balb/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞进行融合,经酶联免疫吸附试验(ELISA)法筛选阳性克隆,并将获得的单克隆抗体与戊型肝炎病毒缅甸株(Burmastrain)和美国株(USAstrain)的重组蛋白(p166Bur、p166US)进行交叉反应测定。结果:最终获得4株能稳定分泌抗-p166Mex的杂交瘤细胞株,即D8G10、E5E12、D4A3、B7E6。其中D8G10,E5E12和B7E6细胞株的培养上清液,还能分别与p166Bur和p166US重组蛋白发生阳性反应。结论:利用已获得的抗-p166Mex单克隆抗体,初步确定3种不同的戊型肝炎病毒重组蛋白(p166Bur、p166US、p166Mex)含有一种共同的抗原表位。  相似文献   
109.
湖南省乙肝病毒基因型分布及临床意义   总被引:1,自引:0,他引:1  
目的 :研究湖南省乙肝病毒 (HBV)基因型分布及临床意义。方法 :选择湖南省HBVDNA阳性慢性乙肝病人共 185例 ,其中病毒携带者 (ASC) 4 2例 ,慢性轻、中度肝炎 (CH) 38例 ,重型肝炎 (FHF) 80例 (伴有肝硬化者 4 9例 ) ,肝细胞癌 (HCC) 2 5例 ,采用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法检测HBV基因型。结果 :基因型B136例 (73.5 % ) ,基因型C 4 9例 (2 6 .5 % )。基因型B在FHF中占绝对优势 (83.7% ) ,其次为HCC(76 % ) ,与ASC(5 7.1% )比较 ,差异有显著性 (P <0 .0 1)。与基因型B相比 ,基因型C在垂直传播感染者中多见 (38.8%与 13.2 % ,P <0 .0 0 1) ;HBeAg阳性率明显增高 (5 7.1%与 30 .9% ,P <0 .0 0 1) ;抗HBe阳性率明显下降 (36 .9%与 6 6 .2 % ,P <0 .0 0 1)。与基因型C相比 ,基因型B感染者ALT水平明显增高 (2 6 4 .5± 2 5 6 .5与 10 0± 12 0 .6 ,P <0 .0 0 1)。结论 :湖南省存在乙肝病毒基因型B和基因型C ;基因型B为优势基因型并与肝脏疾病活动性相关 ,基因型C与母婴垂直传播感染有关  相似文献   
110.
EEGs of 42 patients with herpes zoster and 6 with herpes zoster-associated encephalitis were studied to characterize the nature and prevalence of EEG abnormalities in apparently uncomplicated herpes zoster. Thirty-one percent of herpes zoster patients had EEG changes with reduced rhythm frequency ranging from 7 to 2 Hz activity. Frontotemporal localization was observed in 54% of the abnormal EEGs. When compared to EEG in herpes zoster associated encephalitis, the findings were qualitatively the same, but tended to be more severe in the encephalitis cases. No effect of acyclovir on the EEG could be demonstrated.  相似文献   
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