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91.
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   
92.
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   
93.
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   
94.
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   
95.
肝细胞肝癌(HCC)的发生和演进是一个多基因、多因素的复杂过程,是遗传与环境因素相互作用的结果。单核苷酸多态性(SNP)作为第三代遗传标记,充分反映了个体间的遗传差异,决定了个体对疾病的易感性,正成为肝癌遗传易感性研究的重要工具。  相似文献   
96.
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   
97.

Background

Sever acute malnutrition severely suppresses every component of the immune system leading to increased susceptibility and severity to infection. However, symptoms and signs of infections are often unapparent making prompt clinical diagnosis and early treatment very difficult. The aim of the study was to determine the magnitude of bacteraemia and antimicrobial sensitivity among severely malnourished children.

Methods

Severely malnourished children admitted in Jimma University Specialized Hospital were enrolled between October, 2009 to May, 2010. Blood samples were collected, processed and bacterial isolates were identified using standard bacteriological procedures. Then, antibiotic susceptibility pattern of the isolates was determined by using Kirby-Bauer technique.

Results

Bacteraemia was seen in 35 (20.6%) of the 170 study subjects. There were a total of 35 bacterial isolates, Gram positive bacteria constitute 24(68.6%) of the isolates, where Staphylococcus aureus was the leading Gram positive isolate while Klebsiella species were the dominant Gram negative isolates. Twelve (7.1%) children died and 4 (33.3%) of them had bacteraemia. While susceptibility was more than 80% to Gentamicin, Ciprofloxacin and Ceftriaxone, increased level of resistance was documented to commonly used antibiotics, such as Amoxycillin, Co-trimoxazole and Chloramphenicol.

Conclusion

High prevalence of bacteraemia with predominating Gram positive isolates and increased level of resistance to commonly used antibiotics was shown among severely malnourished children in Jimma. Further studies are required to revise the current guideline for antibiotic choice.  相似文献   
98.
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   
99.
Phospholamban p.Arg14del is reported to cause hereditary cardiomyopathy with malignant ventricular tachycardia (VT) and advanced heart failure. However, the clinical courses of Japanese cardiomyopathy patients with phospholamban p.Arg14del remain uncharacterized. We identified five patients with this variant. All patients were diagnosed with dilated cardiomyopathy (DCM), developed end-stage heart failure and experienced VT requiring implantable cardioverter defibrillator discharge. Four patients survived after implantation of a left ventricular assist device (LVAD), while one patient who refused LVAD implantation died of heart failure. Based on the severe course of the disease, we propose genetic screening for phospholamban p.Arg14del in DCM patients.  相似文献   
100.
This study aimed to identify the factors associated with timely (within four weeks) HCV RNA testing and timely (within six months) DAA initiation following HCV notification in the DAA era. We conducted a cohort study of people with an HCV notification in NSW, Australia. Notifications of positive HCV serology were linked to administrative datasets. Weights were applied to account for spontaneous clearance. Logistic regression analyses were performed. Among 5582 people with an HCV notification during 2016–2017, 3867 (69%) were tested for HCV RNA, including 2770 (50%) who received timely testing. Among an estimated 3925 people with chronic HCV infection, 2372 (60%) initiated DAA therapy, including 1370 (35%) who received timely treatment. Factors associated with timely HCV RNA testing included age (≥30 years), female sex, non-Aboriginal ethnicity, country of birth being Australia, and no history of drug dependence. Factors associated with timely treatment were age (≥30 years), male sex, non-Aboriginal ethnicity, country of birth being Australia, no history of drug dependence, and HCV/HIV co-infection. In the DAA era, 50% of people with an HCV notification did not receive timely HCV RNA testing. Most people with an HCV infection received therapy; however, DAA initiation was delayed among many.  相似文献   
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