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101.
102.
The US Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) together with the Joint United Nations Programme on HIV/AIDS (UNAIDS) recently released new guidelines for HIV testing in health care settings. Both sets of guidelines recommend eliminating individual informed consent in favor of an opt-out approach that requires clients to actively decline the HIV test after a pretest information session. The revised guidelines also recommend reducing the amount of counseling that accompanies the HIV test. Women are more likely than men to be affected by efforts to expand access to HIV testing in health care settings because of women's increased vulnerability to HIV and greater contact with the health care system. Women may also be more susceptible to changes to the consent and counseling process for HIV testing because of their marginalized social status in many settings. More research is needed to document women's experiences with provider-initiated, opt-out HIV testing. Understanding women's experiences will help to formulate feasible and effective strategies to support women and ensure they gain access to HIV treatment services.  相似文献   
103.
Freeman RK 《Seminars in perinatology》2008,32(4):271-Evaluation
Antepartum fetal testing in pregnant patients with hypertensive disorders may be beneficial in preventing stillbirth and hypoxic sequelae in the fetus. The highest risk patients in this category are those with intrauterine growth restriction, superimposed preeclampsia, associated medical complications such as diabetes, systemic lupus erythematosis, chronic renal disease, or history of a prior stillbirth. The current recommended method of primary testing is a twice weekly modified biophysical profile with either a full BPP or a contraction stress test for backup evaluation of those patients with lack of reactivity or decreased amniotic fluid volume on a modified biophysical profile. Even uncomplicated patients with chronic hypertension or pregnancy-induced hypertension carry an increased risk of perinatal mortality and for these patients testing should begin at 33 to 34 weeks gestation. Patients with complications of intrauterine growth restriction, preeclampsia, diabetes, systemic lupus erythematosis, or chronic renal disease should have antepartum testing begin when intervention for fetal indications is judged to be appropriate, usually beginning at about 26 weeks gestation. Doppler velocimetry may be helpful in further evaluation of those patients in the early third trimester with abnormal primary testing.  相似文献   
104.
Growth-restricted fetuses are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Multiple antenatal testing modalities can help document the sequence of fetal deterioration. The full extent of this compromise is best identified by a combination of fetal biometry, biophysical profile scoring, and arterial and venous Doppler. In the preterm growth-restricted fetus, timing of delivery is critically determined by the balance of fetal versus neonatal risks. In the near-term fetus, accurate diagnosis continues to be a challenge as unrecognized growth restriction contributes to a significant proportion of unexplained stillbirths. In this review, we present an integrated diagnostic and surveillance approach that accounts for these factors.  相似文献   
105.
肺炎支原体对呼吸道上皮细胞的黏附以及在其上面滑动是导致肺炎发生的先决条件,机体通过抗体和补体调理吞噬并最终引起细胞毒作用和炎症反应,其中过氧化氢和社区获得性呼吸窘迫综合征毒素是肺炎支原体的重要毒力因子。肺炎支原体实验室检测包括培养、血清学实验和核酸扩增检测技术(NAATs),由于NAATs具有高灵敏度和短周转时间,被认...  相似文献   
106.
This paper presents an analytical model that quantifies the stress ratio between two test specimens for the same probability of failure based on the Weibull weakest link theory. The model takes into account the test specimen geometry, i.e., its shape and volume, and the related non-constant stress state along the specimen. The proposed model is a valuable tool for quantifying the effect of a change of specimen geometry on the probability of failure. This is essential to distinguish size scaling from the actual improvement in measured strength when specimen geometry is optimized, aiming for failure in the gauge section. For unidirectional carbon fibre composites with Weibull modulus m in the range 10–40, it can be calculated by the model that strength measured with a straight-sided specimen will be 1–2% lower than the strength measured with a specific waisted butterfly-shaped specimen solely due to the difference in test specimen shape and volume.  相似文献   
107.
2008年北京市石景山区艾滋病自愿咨询检测状况   总被引:1,自引:0,他引:1  
目的调查北京市石景山区艾滋病自愿咨询检测(VCT)门诊现状,及时了解VCT门诊存在的问题,便于针对性地制定艾滋病健康教育和高危行为干预计划,使VCT门诊更多更及时地发现HIV感染者。方法对2008年1~12月到北京市石景山区疾病预防控制中心(CDC)艾滋病VCT门诊求询的580名求询者进行匿名问卷调查,收集社会人口学特征、求询原因、危险行为等信息,由求询者决定是否接受HIV抗体检测。结果580名求询者以20~40岁青壮年为主,占80.5%;男女比例为1.4∶1;41.6%未婚,52.9%已婚;初中及以下文化占51.0%;求询原因以非婚异性性行为为主,占54.3%;92.4%接受HIV抗体检测,其中阳性3例,HIV抗体检出率为0.6%;3例阳性者均为通过男男性接触感染,男男性接触人群HIV抗体检出率为8.3%。结论求询者以20~40岁青壮年为主,求询原因多样,以非婚异性性行为为主,HIV抗体感染者以男男性接触人群为主。VCT能有效发现HIV抗体阳性者,应广泛开展VCT工作,加强对男男性接触者的行为干预。  相似文献   
108.
Aim: Familial hypercholesterolemia (FH) is an underdiagnosed autosomal dominant genetic disorder characterized by high levels of plasma low-density lipoprotein cholesterol (LDL-C) from birth. This study aimed to assess the genetic identification of FH in children with high LDL-C levels who are identified in a universal pediatric FH screening in Kagawa, Japan. Method: In 2018 and 2019, 15,665 children aged 9 or 10 years underwent the universal lipid screening as part of the annual health checkups for the prevention of lifestyle-related diseases in the Kagawa prefecture. After excluding secondary hyper-LDL cholesterolemia at the local medical institutions, 67 children with LDL-C levels of ≥ 140 mg/dL underwent genetic testing to detect FH causative mutations at four designated hospitals. Results: The LDL-C levels of 140 and 180 mg/dL in 15,665 children corresponded to the 96.3 and 99.7 percentile values, respectively. Among 67 children who underwent genetic testing, 41 had FH causative mutations (36 in the LDL-receptor, 4 in proprotein convertase subtilisin/kexin type 9, and 1 in apolipoprotein B). The area under the curve of receiver operating characteristic curve predicting the presence of FH causative mutation by LDL-C level was 0.705, and FH causative mutations were found in all children with LDL-C levels of ≥ 250 mg/dL. Conclusion: FH causative mutations were confirmed in almost 60% of the referred children, who were identified through the combination of the lipid universal screening as a part of the health checkup system and the exclusion of secondary hyper-LDL cholesterolemia at the local medical institutions.  相似文献   
109.
Self-collection may provide an opportunity for innovation within population-based human papillomavirus (HPV) cervical cancer screening programs by providing an alternative form of engagement for all individuals. The primary objective was to determine willingness to self-collect a vaginal sample for primary HPV screening and factors that impact willingness in individuals who participated in the Human Papillomavirus For Cervical Cancer (HPV FOCAL) screening trial, a large randomized controlled cervical screening trial. A cross-sectional online survey was distributed between 2017 and 2018 to 13,176 eligible participants exiting the FOCAL trial. Bivariate and multivariable logistic regression assessed factors that influence willingness to self-collect on 4945 respondents. Overall, 52.1% of respondents indicated willingness to self-collect an HPV sample. In multivariable analysis, the odds of willingness to self-collect were significantly higher in participants who agreed that screening with an HPV test instead of a Pap test was acceptable to them (odds ratio (OR): 1.45 (95% confidence interval (CI): 1.15, 1.82), those who indicated that collecting their own HPV sample was acceptable to them (p < 0.001), and those with higher educational ascertainment (OR: 1.31, 95% CI: 1.12, 1.54). The findings offer insight into the intentions to self-collect in those already engaged in screening, and can inform cervical cancer screening programs interested in offering alternative approaches to HPV-based screening.  相似文献   
110.
IntroductionEarly diagnosis of HIV is critical for epidemic control. To achieve this, successful testing programmes are essential and test positivity is often used as a marker of their performance. The aim of this study was to analyse trends and predictors of HIV test positivity over time and explore how an understanding of seroconversion rates could build on our interpretation of this indicator among female sex workers in Zimbabwe.MethodsWe analysed HIV test data from Zimbabwe''s nationally scaled sex work programme between 2009 and 2019. We defined test positivity as the proportion of all tests that were HIV positive and measured new diagnoses by estimating seroconversion rates among women with repeat tests, defined as an HIV‐positive test after at least one HIV‐negative test in the programme. We used logistic regression to analyse test positivity over three time‐periods: 2009–2013, 2014–2017 and 2018–2019, adjusting for potential confounding by demographic factors and the mediating effects of time since last HIV test. We calculated the seroconversion rates for the same time‐periods.ResultsDuring the 10‐year study period, 54,503 tests were recorded in 39,462 women. Between 2009 and 2013, 18% of tests were among women who reported testing in the previous 6 months. By 2018–2019, this had increased to 57%. Between 2018 and 2019, test positivity was 9.6%, compared to 47.9% for 2009–2013 (aOR 6.08 95% CI 5.52–6.70) and 18.8% for 2014–2017 (aOR 2.17 95% CI 2.06–2.28). Adjusting for time since last test reduced effect estimates for 2009–2013 (aOR 4.03 95% CI 3.64–4.45) and 2014–2017 (aOR 1.97 95% CI 1.86–2.09) compared to 2018–2019. Among 7573 women with an initial HIV‐negative test in the programme and at least one subsequent test, 464 tested HIV positive at a rate of 3.9 per 100 pyar (95% CI 3.5–4.2).ConclusionsTest positivity decreased among women testing through the programme over time, while seroconversion rates remained high. These declines were partly driven by changes in individual testing history, reflecting comprehensive coverage of testing services and greater knowledge of HIV status, but not necessarily declining rates of seroconversion. Understanding testing history and monitoring new HIV infections from repeat tests could strengthen the interpretation of test positivity and provide a better understanding of programme performance.  相似文献   
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