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Population-based data on sexually transmitted infections (STI), bacterial vaginosis (BV), and candidiasis reflect the epidemiological situation more accurately than studies performed in specific populations, but such data are scarce. To determine the prevalence of STI, BV, and candidiasis among women of reproductive age from a resource-poor community in Northeast Brazil, a population-based cross sectional study was undertaken. All women from seven hamlets and the centre of Pacoti municipality in the state of Ceará, aged 12 to 49 years, were invited to participate. The women were asked about socio-demographic characteristics and genital symptoms, and thereafter examined gynaecologically. Laboratory testing included polymerase chain reaction (PCR) for human papillomavirus (HPV), ligase chain reaction (LCR) for Chlamydia trachomatis and Neisseria gonorrhoeae, ELISA for human immunodeficiency virus (HIV), venereal disease research laboratory (VDRL) and fluorescent treponema antibody absorption test (FTA-ABS) for syphilis, and analysis of wet mounts, gram stains and Pap smears for trichomoniasis, candidiasis, and BV. Only women who had initiated sexual life were included in the analysis (n = 592). The prevalences of STI were: HPV 11.7% (95% confidence interval: 9.3-14.7), chlamydia 4.5% (3.0-6.6), trichomoniasis 4.1% (2.7-6.1), gonorrhoea 1.2% (0.5-2.6), syphilis 0.2% (0.0-1.1), and HIV 0%. The prevalence of BV and candidiasis was 20% (16.9-23.6) and 12.5% (10.0-15.5), respectively. The most common gynaecological complaint was lower abdominal pain. STI are common in women in rural Brazil and represent an important health threat in view of the HIV pandemic.  相似文献   
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We examined responses of benthic macroinvertebrate communities to natural geothermal discharges in 32 streams in Yellowstone National Park (YNP), USA. Geothermal discharges played a major role in structuring benthic communities in YNP, as downstream communities were characterized by low species richness, reduced abundance of EPT taxa and increased abundance of tolerant caddisflies (Trichoptera), chironomids and non-insects. While some taxa were a subset of tolerant organisms that were also common at references sites, others (the damselfly Argia sp., the caddisfly Oxyethira sp. and the exotic New Zealand mudsnail Potamopyrgus antipodarum Gray 1843) were found almost exclusively in geothermal streams. Because geothermal waters are a common feature of YNP, monitoring programs designed to assess long-term status and trends of Yellowstone’s aquatic ecosystems must account for the influence of these discharges. To separate geothermal effects from other potential anthropogenic disturbances in YNP (e.g., atmospheric deposition, road construction, wastewater, global change), we developed a multimetric index based on responses of benthic communities to geothermal discharges. Streams were placed into one of four geothermal categories based on conductivity (reference = < 150 μS/cm; low, moderate and high = 151–300, 301–600 and >600 μS/cm, respectively). The index clearly distinguished among these categories and showed a well-defined threshold response to geothermal effects at very low levels of conductivity. Although the index was specific to geothermal effects, the approach used to develop the index has broad applicability for other systems where impacts of stressors must be assessed within the context of natural environmental gradients. Our findings may provide important insights into how benthic macroinvertebrate communities respond to global change. Reduced discharge and warmer temperatures predicted for Rocky Mountain streams may favor the establishment and expansion of exotic species such as New Zealand mudsnails (P. antipodarum), which are highly tolerant of geothermal influences.  相似文献   
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Bioluminescence resonance energy transfer (BRET) is an increasingly popular technique for studying protein-protein interactions in live cells. It is particularly suitable for real-time monitoring of such interactions, however, the timescale over which assays can be carried out is currently relatively short (minutes) due to substrate instability. We present a new derivation of the BRET technology, termed 'extended BRET' (eBRET), which now enables protein-protein interactions to be monitored in real-time for many hours. This capability has significant benefits for investigating cellular function over extended timescales, as we have illustrated using the agonist-induced G-protein coupled receptor/beta-arrestin interaction. The potential for studying the modulation of such interactions by agonists, antagonists, inhibitors, dominant negative mutants and co-expressed accessory proteins is substantial. Furthermore, the advantages of eBRET have important implications for the development of high-throughput BRET screening systems, an ever-expanding area of interest for the pharmaceutical industry.  相似文献   
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SERRATE: a new player on the plant microRNA scene   总被引:7,自引:0,他引:7  
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Coral diseases are taking an increasing toll on coral reef structure and biodiversity and are important indicators of declining health in the oceans. We implemented standardized coral disease surveys to pinpoint hotspots of coral disease, reveal vulnerable coral families and test hypotheses about climate drivers from 39 locations worldwide. We analyzed a 3 yr study of coral disease prevalence to identify links between disease and a range of covariates, including thermal anomalies (from satellite data), location and coral cover, using a Generalized Linear Mixed Model. Prevalence of unhealthy corals, i.e. those with signs of known diseases or with other signs of compromised health, exceeded 10% on many reefs and ranged to over 50% on some. Disease prevalence exceeded 10% on 20% of Caribbean reefs and 2.7% of Pacific reefs surveyed. Within the same coral families across oceans, prevalence of unhealthy colonies was higher and some diseases were more common at sites in the Caribbean than those in the Pacific. The effects of high disease prevalence are potentially extensive given that the most affected coral families, the acroporids, faviids and siderastreids, are among the major reef-builders at these sites. The poritids and agaricids stood out in the Caribbean as being the most resistant to disease, even though these families were abundant in our surveys. Regional warm temperature anomalies were strongly correlated with high disease prevalence. The levels of disease reported here will provide a much-needed local reference point against which to compare future change.  相似文献   
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