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991.
992.
ABSTRACT: BACKGROUND: The HIV/AIDS pandemic remains a leading challenge for global health. Although condoms are acknowledged for their key role on preventing HIV transmission, low and inappropriate use of condoms persists in Tanzania and elsewhere in Africa. This study assesses factors affecting acceptability of condom promotion and distribution among Tanzanian adolescents. METHODS: Data were collected in 2011 as part of a larger cross-sectional survey on condom use among 10-19 year-olds in Mpwapwa and Mbeya rural districts of Tanzania using a structured questionnaire. Associations between acceptability of condom promotion and distribution and each of the explanatory variables was tested using Chi Square. Multivariate logistic regression model was used to examine independent predictors of the acceptability of condom promotion and distribution using STATA (11) statistical software at 5% significance level. RESULTS: Mean age of the 1,327 adolescent participants (50.5% being males) was 13.5 years (SD=1.4). Acceptance of condom promotion and distribution was found among 37% of the adolescents. Being sexually active and aged 15-19 was the strongest predictor of the acceptability of condom promotion and distribution (OR=7.78, 95% CI 4.65-12.99). Others were; not agreeing that a condom is effective in preventing transmissions of STIs including HIV (OR=0.34, 95% CI 0.20-0.56), being a resident of Mbeya rural district (OR=1.67, 95% CI 1.28-2.19), feeling comfortable being seen by parents/guardians holding/buying condoms (OR=2.20, 95% CI 1.40-3.46) and living with a guardian (OR=1.48, 95% CI 1.08-2.04). CONCLUSION: Acceptability of condom promotion and distribution among adolescents in Mpwapwa and Mbeya rural is low. Effect of sexual activity on the acceptability of condom promotion and distribution is age-dependent and was the strongest. Feeling comfortable being seen by parents/guardians buying or holding condoms, perceived ability of condoms to offer protection against HIV/AIDS infections, district of residence and living arrangements also offered significant predictive effect. Knowledge of these factors is vital in designing successful and sustainable condom promotion and distribution programs in Tanzania. Key words Acceptability, condom promotion and distribution, adolescents, Tanzania.  相似文献   
993.
There has been an overall increase in the incidence of multiple pregnancies and assisted reproduction technology is largely responsible for this rise. Although twins may appeal to couples undergoing in vitro fertilisation (IVF), they have been associated with serious health consequences to the babies, their mothers and the family unit, as well as having massive financial implications for the National Health Service. Transfer of more than one embryo during IVF is mainly responsible for IVF twins, and elective transfer of a single embryo at a time with cryopreservation of surplus embryos for later transfer has been shown to be an effective strategy to minimise the risk of twins without compromising IVF success rates. Factors that will impact on the success of the policy of elective single embryo transfer (eSET) include improvement in embryo selection for transfer, better cryopreservation techniques and adequate state funding for IVF. However, in implementing the policy of eSET it is important that each case is assessed on an individual basis since in some situations (e.g. in older women) the transfer of two embryos may be more cost effective. Adequate and continuous education of all stakeholders is essential if the policy of eSET is to be successful in the UK.  相似文献   
994.
ABSTRACT: BACKGROUND: During a period of evolving international consensus on how to engage communities in research, facilitators and barriers to participation in HIV prevention research were explored in a rural plantation community in the coastal region of Cameroon. METHODS: A formative rapid assessment using structured observations, focus group discussions (FGD), and key informant interviews (KIIs) was conducted with a purposive non-probabilistic sample of plantation workers and their household members. Eligibility criteria included living or working >1 year within the plantation community and age >18 years. Both rapid and indepth techniques were used to complete thematic analysis. RESULTS: Sixty-five persons participated in the study (6 FGDs and 12 KIIs). Participants viewed malaria and gastrointestinal conditions as more common health concerns than HIV. They identified three factors as contributing to HIV risk: concurrent sexual relationships, sex work, and infrequent condom use. Interviewees perceived that the community would participate in HIV research if it is designed to: (1) improve community welfare, (2) provide comprehensive health services and treatment for illnesses, (3) protect the personal information of participants, especially those who test positive for HIV, (4) provide participant incentives, (5) incorporate community input, and (6) minimize disruptions to "everyday life". Barriers to participation included: (1) fear of HIV testing, (2) mistrust of researchers given possible disrespect or intolerance of plantation community life and lack of concern for communication, (3) time commitment demands, (3) medical care and treatment that would be difficult or costly to access, and (4) life disruptions along with potential requirements for changes in behaviour (i.e., engage in or abstain from alcohol use and sex activities). CONCLUSIONS: Consistent with UNAIDS guidelines for good participatory practice in HIV prevention research, study participants placed a high premium on researchers' politeness, trust, respect, communication, tolerance and empathy towards their community. Plantation community members viewed provision of comprehensive health services as an important community benefit likely to enhance HIV research participation.  相似文献   
995.
The final effluents of three (Alice, Dimbaza, and East London) wastewater treatment plants (WWTPs) were evaluated to determine their physicochemical quality and prevalence of multiple antibiotics resistant (MAR) Pseudomonas species, between August 2007 and July 2008. The annual mean total Pseudomonas count (TPC) was 1.20 × 10(4) (cfu/100 mL), 1.08 × 10(4) (cfu/100 mL), and 2.66 × 10(4) (cfu/100 mL), for the Alice, Dimbaza, and East London WWTPs respectively. The effluents were generally compliant with recommended limits for pH, temperature, TDS, DO, nitrite and nitrate; but fell short of target standards for turbidity, COD, and phosphate. The tested isolates were highly sensitive to gentamicin (100%), ofloxacin (100%), clindamycin (90%), erythromycin (90%) and nitrofurantoin (80%); whereas high resistance was observed against the penicillins (90-100%), rifampin (90%), sulphamethoxazole (90%) and the cephems (70%). MAR index ranged between 0.26 and 0.58. The study demonstrated that MAR Pseudomonas species were quite prevalent in the final effluents of WWTPs in South Africa; and this can lead to serious health risk for communities that depend on the effluent-receiving waters for sundry purposes.  相似文献   
996.
During 2010–2011, we investigated interspecies transmission of partetraviruses between predators (humans and chimpanzees) and their prey (colobus monkeys) in Côte d’Ivoire. Despite widespread infection in all species investigated, no interspecies transmission could be detected by PCR and genome analysis. All sequences identified formed species- or subspecies (chimpanzee)-specific clusters, which supports a co-evolution hypothesis.  相似文献   
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998.
999.

Background

Elevated concentrations of troponin T have prognostic impact in patients with various cardiovascular diseases including those with severe aortic stenosis. Transcatheter aortic valve implantation (TAVI) has improved prognosis for patients without a surgical option. Whether this affects the prognostic value of preinterventional troponin T remains unclear.

Methods

We therefore conducted a prospective study in 198 consecutive patients with subsequent, successful transfemoral TAVI and analyzed cardiac troponin T (cTnT) levels with a new generation, high-sensitive troponin T assay before and after TAVI, as well as their prognostic value after 12 months.

Results

Patients with severe aortic stenosis (AS) showed significant elevation of preinterventional cTnT levels. Postinterventional cTnT levels significantly rose further about sevenfold after transfemoral TAVI and peaked at day three until they steadily declined thereafter. Baseline renal function (P = 0.011), the duration of intraprocedural rapid pacing (P = 0.0012), and baseline cTnT (P = 0.0001) values predicted the magnitude of postinterventional cTnT elevations. Interestingly, Kaplan–Meier curve analysis revealed, that although cTnT levels were not predictive for short-term mortality, preinterventional as well as postinterventional peak cTnT showed prognostic value for 1-year mortality, regardless of successful TAVI.

Conclusions

Pre- and postinterventional hscTnT levels signal adverse 1-year mortality in patients with severe AS independent of successful aortic valve replacement.  相似文献   
1000.
We show that the canonical single frequency sarcomeric SHG intensity pattern (SHG-IP) of control muscles is converted to double frequency sarcomeric SHG-IP in preserved mdx mouse gastrocnemius muscles in the vicinity of necrotic fibers. These double frequency sarcomeric SHG-IPs are often spatially correlated to double frequency sarcomeric two-photon excitation fluorescence (TPEF) emitted from Z-line and I-bands and to one centered spot SHG angular intensity pattern (SHG-AIP) suggesting that these patterns are signature of myofibrillar misalignement. This latter is confirmed with transmission electron microscopy (TEM). Moreover, a good spatial correlation between SHG signature of myofibrillar misalignment and triad reduction is established. Theoretical simulation of sarcomeric SHG-IP is used to demonstrate the correlation between change of SHG-IP and -AIP and myofibrillar misalignment. The extreme sensitivity of SHG microscopy to reveal the submicrometric organization of A-band thick filaments is highlighted. This report is a first step toward future studies aimed at establishing live SHG signature of myofibrillar misalignment involving excitation contraction defects due to muscle damage and disease.OCIS codes: (180.4315) Nonlinear microscopy, (190.4160) Multiharmonic generation, (170.3880) Medical and biological imaging  相似文献   
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