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31.
Summary A neurological complication occurs in 40–60% of HIV infected patients during the course of the disease. In 10–20% the neurological complication is the first manifestation of the HIV infection. A reliable neuropathological diagnosis is a prerequisite for a specifically selected treatment. While modern computer-assisted imaging techniques, such as computed tomography or magnetic resonance imaging, do possess a high sensitivity, they do not as a rule permit an unambiguous diagnosis.Between October 1989 and July 1994 we biopsied 38 HIV infected patients stereotactically. The indication for the biopsy was determined by having radiologically detectable lesions with no regression tendency in patients under antitoxoplasmosis therapy. In 89% an unambiguous diagnosis wa made based on the biopsy; 11 % of the biopsies were not diagnostic. For the most part, toxoplasmosis (31%) and progressive multifocal leucoencephalopathy (29%) were involved. 18% of the patients suffered from a non-Hodgkin lymphoma. The foci were primarily frontal (47%), parietal (21%) or localised in the basal ganglia area (11%). The result of the biopsy led to a change in treatment for 52% of the patients. Morbidity and mortality of the operation were 0%.The results or our research series are similar to other groups. It was shown that stereotactic brain biopsy is a safe and effective method for establishing a sound basis for treating the frequently life-threatening cerebral complications of AIDS.  相似文献   
32.
Debate about the best paradigm for mental health nursing is compounded by threats from mainstreaming and genericism. In nursing education, integrated practice may have been devalued in a matrix of reductionist disciplines. The 'gendered' nature of professional knowledge may create a schismatic and self-defeating attitude in nurses. Conversely, nurses may be exhorted to adopt a 'male' paradigm in order to gain academic credibility, in which the caring dimension may be lost. Other polarities such as ideological distinctions between treatment in hospital and care in the community lead to conceptual confusion. These schisms in care are detrimental to both professionals and users. The writers argue that these tensions may be addressed in an 'androgenous' model which presents a challenge to both value systems, rejects the dominance of schismatic models, and offers the potential for a new professional integrity.  相似文献   
33.
Abstract Periodontal diseases may be the first clinical sign of human immunodeficiency virus (HIV)-infection. Since the immunosuppression and subsequent susceptibility may alter the responses of the oral tissues as well as the microflora, both periodontal treatment and result of therapy may be modified. The periodontal diseases in HIV-seropositive patients include common as well as less conventional forms of gingivitis and periodontitis, and bacteria, mycotic and viral infections are seen. Neoplasias may also involve the periodontium; most common are Kaposi's sarcoma and non-Hodgkin's lymphoma. Recent studies of unselected groups of patients indicate that periodontal health in at least some groups of HIV-seropositive patients is better than previously reported.  相似文献   
34.
An extensive examination of the tongue was performed at autopsy in 20 consecutive patients who had died with AIDS. Abnormalities in the tongue were detected in 18 (90%) of the cases; the commonest lesions were ulceration (11), candidosis (8) and small foci of hyperkeratosis (10). The most extensive lesions were caused by Aspergillus infection (1), non-Hodgkin's lymphoma juxtaposed with Kaposi's sarcoma (1), herpetic infection (1) and candidosis (5). The disease causing death was identified in the tongue in two cases. There was a surprisingly low prevalence of oral hairy leukoplakia. which may be related to anti-viral or retroviral therapy.  相似文献   
35.
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment.  相似文献   
36.
A new type of pseudodipeptide isostere exampled by Phe ψ[CH2CH(OH)]Phe was synthesized from phenylalanine. The H]V protease inhibitory activity (IC50) of Noa-His-Pheψ[CH2CH(OH)]Phe-Ile-Amp was 0. 8 pmol·L-1.  相似文献   
37.
Abstract The paper contrasts understandings of knowledge grounded in Enlightenment norms with the departures from those norms taken by some strands of feminism and hermeneutics, as well as the contributions made by the writing of Michel Foucault. A reading of Foucault's writings on knowledge, power and the discursive constitution of self and world is offered as a potentially useful frame within which to raise questions about nursing, nurses and knowledge.  相似文献   
38.
39.
HIV疫苗     
尽管经过了 2 0年的努力 ,对预防HIV/AIDS感染的疫苗开发仍然没有确切的结果。本文分析了开发HIV疫苗如此艰难的原因 ,提出了通过免疫学途径研究针对发达国家感染者的最佳候选疫苗 ,然后再将最有希望的疫苗引入发展中国家 ,以努力预防感染和发病的工作计划。  相似文献   
40.
1275 patients were evaluated for HIV-1+2 seroprevalence and its association with clinical symptoms of HIV infection. Of 667 apparently healthy subjects, 8.2% had anti-HIV-1 antibodies. In 465 patients with clinical signs of AIDS, 39.4% were seropositive. 143 patients with miscellaneous symptoms had positive predictive values for HIV infection between 67% (vaginal ulcerations) and 20% (profound pyogenic abscesses). The WHO definition for AIDS had a specificity of 78.3%, a sensitivity of 72.2% and a predictive value of 61.6%.  相似文献   
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