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81.
Summary Morphine and its derivatives are metabolized by the liver microsomal enzyme system with a high first-pass effect after oral application. In four of 44 HIV-infected i.v. drug abusers who participated in a levomethadon maintenance program, we observed sustained symptoms of under-dosage and loss of effect of there to fore well-tolerated substitution therapy during rifampin treatment or therapy with zidovudine or fucidic acid. As a pharmacological model substance for cytochrome p 450 enzymes, measurement of antipyrine in serum by high pressure liquid chromatography revealed induction of cytochrome p 450 isoenzymes. The half-life of antipyrine decreased (patient 1 from 11.3 to 8.4 h and patient 2 from 10.7 to 7.6 h after rifampin, patient 3 from 12.2 to 8.6 h after fucidic acid, and patient 4 from 10.6 to 8.6 h after zidovudine). In i.v. drug abusers on levomethadon maintenance programs, adjustment of the levomethadon dosage may be necessary when specific therapy for HIV infection and associated diseases requires the use of drugs known to be potent inducers of the liver microsomal enzyme system.Abbreviations IVDA intravenous drug abusers - C total body clearance - PCP pneumoncystis carinii pneumonia - INH isonazid - EMB ethambutol - PZA pyrazinamide - t1/2 half-life  相似文献   
82.
GKT原理的模拟犯罪测试范式实验研究   总被引:2,自引:0,他引:2  
目的:本实验旨在以实际犯罪较接近的实验场景验证GKT的测谎机制,并探讨其对罪犯以及其他嫌疑人的判定有效性。方法:以72名健康大学生为被试,让被试在模拟犯罪的背景下采用三种包含不同说谎和认知成分的回答方式进行测谎测试,采用Limestone测谎仪测量被试皮肤电反应。结果:回答方式与角色两因子在判定分数上的主效应均显著,交互作用不显著。结论:在模拟犯罪测试范式下,GKT模式中认知与说谎机制是共存的,其中认知成分不占主要地位,说谎成分占主要地位,GKT模式无法兼顾有效地判定"犯罪"和"知情无辜"角色,需进一步改进。  相似文献   
83.
以无形资产为切入点.探讨图书馆在网络环境下与各类信息源及用户的辩证关系;以人为本的知识资本运营.无形资产的投入和知识产权保护比以往更加重要;提出社会无形资产概念:甄别信息资源专有权与公有权.论证图书馆社会角色;辨析图书馆知识管理.无形资产评估、立法理念。  相似文献   
84.
Summary Frequent complications of human immunodeficiency virus infection are hematopoietic failure and poor tolerance of myelosuppressive drugs. Reasons for neutropenia resulting from hematopoietic failure are infection of the bone marrow and hematotoxicity of treatment with zidovudine, ganciclovir, sulfonamides, and interferons. Moreover, tumor necrosis factor-, transforming growth factor- and interferon- have been shown to suppress proliferation of bone marrow cells. Both granulocyte (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) increase neutrophil counts and ameliorate phagocytic and bactericidic function of neutrophils. We report eight cases of AIDS patients with serious infections and neutropenia (< 750 cells/l), who were treated concomitantly with recombinant human G-CSF (3–4 g subcutaneously per kilogram body weight daily). G-CSF treatment was well tolerated in all patients and showed no side effects or disturbances of other lineages than neutrophils. Life-threatening bacterial infections were treated successfully by stimulating the neutrophil immune system. This therapy shortened the duration of subsequent treatment with antibiotics. Since human immunodeficiency virus infects CD4-positive monocytes and macrophages, which are stimulated by GM-CSF, G-CSF seems to be the cytokine of choice, if stimulation of the neutrophil lineage is warranted.Abbreviations G-CSF granulocyte colony-stimulating factor - GM-CSF granulocyte-macrophage colony-stimulating factor - HIV human immunodeficiency virus  相似文献   
85.
This study examined the effects of certain characteristics of human immunodeficiency virus (HIV)-infected patients related to the risks of practising unprotected sex (UPS) among 919 HIV-infected patients who attended the sexually transmitted disease (STD) clinic of the Taipei City STD Control Center, Taiwan, during the period January–July 2004. After learning that they were HIV-positive, 517 (56%) subjects had practised UPS, 476 (52%) had a new STD diagnosis, and 106 (12%) had used some form of injected drug. UPS was reported by 76% of homosexual/bisexual males, 19% of heterosexual males and 5% of females, and was reported more often by those individuals with casual sexual partners (p < 0.001). According to multivariate logistic regression analyses, UPS was associated with male-tomale sexual intercourse (OR 2.46; 95% CI 1.26–4.86, p < 0.001), with casual sexual partners (OR 2.82; 95% CI 1.62–4.88, p < 0.001), and with an individual's knowledge of his/her HIV status for > 11 years (OR 2.06; 95% CI 1.02–4.18, p < 0.05). Although using anti-retroviral therapy to prevent sexual transmission of HIV is rational, the avoidance of at-risk sexual behaviour should also be a priority among HIV-seropositive individuals. Ongoing risk-reduction counselling related to HIV transmission is needed to reduce certain sexual behaviours associated with HIV transmission.  相似文献   
86.
The prognostic and protective role of antibodies mediating cellular cytotoxicity (ADCC) and neutralization was evaluated in sera of HIV-1-infected mothers and their consecutively followed children. The presence and titres of ADCC mediating and/or neutralizing antibodies in maternal sera did not predict HIV-1 infection in their respective children. No significant difference in the sera from the children was seen when comparing the presence of neutralizing antibodies between the uninfected and infected children. Stratification of the infected group according to clinical status revealed differences. Only one of 24 AIDS patients had a high neutralizing titre against IIIB. Four patients had a very low titre and the remaining had no detectable neutralizing antibodies at all. In contrast, 10/17 infected non-AIDS children had neutralizing antibodies. Similarly, no significant difference was seen when comparing the presence of ADCC-mediating antibodies between the uninfected and the infected group of children. However, a significantly higher frequency of ADCC was seen in the seropositive non-AIDS children compared with the AIDS children. This study clearly shows that the presence of antibodies mediating ADCC and neutralization in infected children, 0-2 years old, is associated with a better clinical status and delayed disease progression.  相似文献   
87.
Smooth-muscle neoplasms are rarely located in the spleen. They have been previously reported in five cases of children with human immunodeficiency virus (HIV) infection/acquired immunodeficiency syndrome (AIDS). Two cases of children with HIV infection/AIDS with autopsy and surgical pathology evidence of multiple smooth-muscle neoplasms with splenic involvement are presented. DNA was extracted from histology slides in both cases for analysis for Epstein Barr (EB) virus. In both cases, the presence of EB virus was confirmed. This paper documents two additional cases of the unusual phenomenon of splenic involvement by smooth-muscle neoplasms in the setting of AIDS in childhood and further supports the role of EB virus in the development of these neoplasms. Received: 27 January 1999 / Accepted: 23 August 1999  相似文献   
88.
HIV-1-positive antisera were tested for their ability to lyse HIV-1-infected cells in the presence of active complement. Cytolytic effects caused by sera derived from infected humans were slower than those observed with sera from immunised chimpanzees. Lytic but also negative sera were found among HIV-1-infected asymptomatic men as well as among clinical AIDS cases. Human antisera that lysed infected cells reacted similarly irrespective of whether the complement was heterologous or autologous. Analysis of complement-mediated lysis using defined antisera against recombinant HIV-1 env or core antigens suggested that gp160/gp120 and p24 can act as target antigens for an antibody- and complement-mediated cytolysis of infected cells. Complement alone reduced the spread of HIV-1 infection in CD4+ cells and the ability of HIV-1 and HIV-2 to form plaques in CD4-transfected HeLa cells. Co-operative effects of specific antibodies and complement were the most effective in inhibiting HIV infections.  相似文献   
89.
Summary The personnel in laboratories that utilize tissue and fluids from humans and other primates are at risk for infection with agents, including the viruses causing hepatitis, AIDS, and other infective agents such as mycobacteria tuberculosis. To minimize the chance of infection of laboratory personnel, carefully organized policies and procedures to minimize exposure to infective agents must be established in research laboratories. We outline some of the approaches of hospital clinical laboratories which have proved most effective in minimizing transmission of infections from samples to laboratory personnel. Also, we discuss simple considerations important in the use and in the selection of safety equipment. These guidelines and references to other safety information are provided to aid research laboratories in establishing safety procedures that will minimize chances of personnel contamination with infective agents from research samples.  相似文献   
90.
The pathophysiologic basis for the exuberant intracellular growth of Mycobacterium avium complex (MAC) in AIDS patients is unclear but may relate to altered expression of modulatory cytokines. Interleukin (IL)-1, IL-6, and TNF- expression by monocytes from AIDS patients and healthy subjects (HS) stimulated with isogeneic MAC strains (SmT, smooth-transparent, virulent; SmD, smooth-domed, avirulent) was examined. Spontaneous cytokine production was not observed in patients with AIDS. MAC strains induced less IL-1 and IL-1 release in AIDS patients than HS (P < 0.05). The ratio of cell-associated to supernatant IL-1 also was increased in AIDS patients (P = 0.03). IL-1 mRNA expression paralleled protein release in either group of subjects. In both HS and AIDS patients, stimulation with SmD induced more IL-1 and TNF- release by monocytes compared to SmT. In AIDS patients, SmD also induced greater IL-6 release than SmT (P < 0.01). Alterations in monocyte expression and compartmentalization of the regulatory cytokines IL-1 and IL-6 may enhance bacterial replication and contribute to the patho-genesis of MAC infection in AIDS.  相似文献   
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