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81.
目的 分析我国暗娼人群艾滋病相关行为变化及艾滋病病毒(HIV)感染流行趋势,为艾滋病综合防治和科学干预提供信息和依据.方法 对2004-2008年连续开展监测的15个国家级暗娼综合监测点,在监测期内以重复横断面调查的方法对社区娱乐场所及街头的暗娼人群进行问卷调查并采血,每个监测点每轮调查的样本量约为400例.结果 2004-2008年连续监测的15个国家级暗娼综合监测点,5年间监测对象HIV抗体阳性检出率(中位数)均为0.0%;梅毒抗体阳性检出率(中位数)分别为:0.5%、1.8%、1.6%、1.8%和1.0%.最近1次商业性行为安全套使用率(中位数)分别为:81.8%、80.5%、84.6%、87.0%和88.9%;最近1个月商业性行为坚持使用安全套的比例(中位数)分别为:65.8%、59.6%、60.3%、59.8%和73.7%.艾滋病知识知晓率(中位数)分别为:74.3%、84.1%、65.2%、66.0%和74.3%;接受过HIV检测并知晓检测结果者的比例(中位数)分别为:12.4%、20.4%、25.8%、25.3%和31.7%;最近1年接受过干预服务者的比例(中位数)分别为:46.4%、76.1%、72.1%、95.0%和90.8%.结论 暗娼人群商业性行为坚持使用安全套的比例和艾滋病知识知晓率有待于进一步提高.接受过HIV检测并知晓检测结果和最近1年接受过干预服务者的比例呈上升趋势.HIV感染率总体水平低,但高危行为状况不容乐观,需不断开展干预和综合防治工作.  相似文献   
82.
An important operational aspect of Syringe Exchange Programmes (SEPs) is the venue of service delivery. This report describes the programmatic features of the Sacramento Area Needle Exchange (SANE), an illegal SEP operating in California, USA. SANE utilises “satellite exchangers” to distribute the bulk of its syringes and HIV risk reduction supplies. Advantages of relying primarily on Designated Exchangers (DE) for delivery of SEP services are that it: (1) allows for coverage of a large geographical area; (2) keeps operational cost low; (3) provides syringes to clients who may not want to or cannot use fixed site programmes; (4) limits the possibility of detection of programme personnel and clients by law enforcement. Limitations are that: (1) it is not as conducive as fixed sites to providing a wide range of ancillary services; (2) it may not be optimal for drug users who do not want to be reliant on other people for access to syringes; (3) those who receive services from a satellite exchanger may not derive as much counselling and referral services as direct exchangers. The lack of legal status, political support and adequate funding threatens the programme’s existence.  相似文献   
83.
Epitope Context and Reshaping of Activated T Helper Cell Repertoire   总被引:1,自引:0,他引:1  
In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells.  相似文献   
84.
Serial serum samples from the 21 HIV-infected Norwegian hemophiliacs have been assayed for the presence of HIV antigen and antibodies to HIV specific for the core protein p24 and the envelope protein gp41. HIV antigen was detected in 4 patients, of whom 3 have developed AIDS to date. HIV antigen appeared in serum 10 to 24 months before the diagnosis in these patients. Antibodies to gp41 was a constant finding. Antibodies to p24 disappeared from the serum in 1 patient who developed AIDS and from 3 persons free of symptoms related to the HIV infection. The detection of HIV antigen in HIV antibody-positive hemophiliacs appears to be of considerable prognostic significance.  相似文献   
85.
A questionnaire survey of 260 health care workers from 13 randomly selected health care facilities was undertaken. Their knowledge, attitude, belief and blood handling practices regarding HIV/AIDS were enquired about. Virtually all (99.0%) respondents had heard about AIDS but only 57.0% had seen an AIDS patient before. Although 83.0% knew that AIDS is caused by a virus, a high proportion still confuses mode of transmission with causative agent. Deficient knowledge was exhibited when asked about groups of people who were at a higher risk of contracting HIV and AIDS: Only 54.6% and 51.5% identified homosexuals and IV drug users as being at a higher risk. Almost all (97.0%) of our respondents claimed to have been more careful in their blood handling practices since the emergence of AIDS, 68.5% wore gloves for all procedures involving handling of blood and 28.5% sometimes although as many as 30.4%, 40.4% and 18.1% do not wear gloves for cleaning up blood stained materials, nursing procedures and taking obstetric delivery respectively. It was evident from their responses that not all the health workers knew the correct method for disposing of used bloodstained instruments and left-over blood samples and neither were they all adhering to the safety guidelines recommended for handling these materials. Education of all health care workers in Nigeria on the Universal Precautions Guidelines issued by the Centers for Disease Control (CDC) in 1987 regarding blood, body fluids and contaminated instruments' handling precautions is urgently recommended.  相似文献   
86.
目的调查HIV/AIDS病人结核菌素(PPD)试验反应状况及与免疫系统受损程度的联系,并探讨其预防和治疗结核病的意义。方法采用前瞻性病例对照研究方法,对40例HIV(+)者和202例HIV(-)者做结核菌素试验,并对HIV(十)者做CD4、CD8细胞计数测定,对HIV(+)分组服药,观察胸部病变情况。结果HIV(+)与HIV(-)者PPD阳性率分别为12.5%、28.2%(P<0.05)。当CD4细胞计数下降时,PPD反应减弱。CD4<200个/mm3时PPD均无反应(0×0).病例服药组经化学药物预防治疗后其肺部病变异常率小于病例对照组。结论HIV(+)者中PPD阳性率显著低于HIV(-)者。CD4细胞数下降可能是艾滋病并发结核的主要原因.对HIV/AIDS患者使用化学药物预防和治疗结核是有效的。  相似文献   
87.
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   
88.
89.
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   
90.
This paper draws on two reviews commissioned by the UK Department for International Development in 2006-2007 that explore progress in linking HIV prevention and maternity services in sub-Saharan Africa. Although pilot and demonstration projects have been successful, progress in scaling up PMTCT has been slow, reaching just 11% of pregnant HIV positive women in much of Africa, less than half the percentage of coverage achieved by antiretroviral treatment programmes for adults in need. Despite ongoing efforts to promote comprehensive approaches, significant policy, financing and institutional barriers, and weak co-ordination and leadership, continue to hamper progress. Maternal health services face human and financial resource shortages which affect their capacity to integrate HIV prevention. Both HIV and maternal health programmes often receive targeted financial and technical assistance that does not take the other into account. However, proposals in 2007 from a number of countries to the Global Fund to Fight AIDS, TB and Malaria incorporate sexual and reproductive health programming that will have an impact on HIV, including certain maternity services. Moreover, Botswana, Kenya and Rwanda have shown that progress can be made where national commitment and increased resources are enabling maternal and newborn care to address HIV.  相似文献   
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