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Purpose  

Proctalgia fugax (PF) is a benign anorectal condition which has been described in the literature since the nineteenth century commonly presenting to general surgeons. There is little high level evidence on the subject and its therapeutic modalities. We aimed through this systematic literature review to outline the definition and diagnostic criteria of this condition, the aetiology and differential diagnoses and describe the different treatment modalities that have been attempted and their success.  相似文献   
994.
ObjectiveTo investigate the prevalence of pathogens of abnormal vaginal discharges and to improve the current syndromic management of abnormal vaginal discharge.MethodsA prospective study of pathogens of abnormal vaginal discharge was carried out from December 2007 to December 2008. Samples of female genital swabs were collected from Obstetrics and Gynecology Units of Aminu Kano Teaching Hospital, Kano, Nigeria, and analyzed by microscopy, culture and sensitivity test in Medical Microbiology Laboratory of Aminu Kano Teaching Hospital.ResultsMicroorganisms were detected in 70% (1 400) of a total 2 000 female genital swabs studied. Candida species peaked with 42.0% (840), followed by Gardnerella vaginalis, a pathogen of bacteria vaginosis with 26.0%. The distribution of abnormal vaginal discharge was highest in young adults aged from 21 to 30 years.ConclusionsThe commonest Microorganisms of infective vaginal discharge were Candida species, followed by Gardnerella vaginalis, a pathogen of bacterial vaginosis. Vaginal discharge was prevalent among young adults. We recommend prevention, early diagnosis and prompt treatment of infected female, especially among the young, sexually active group in order to reduce the menace of HIV transmission.  相似文献   
995.
American black bears survive winter months without food and water while in a mildly hypothermic, hypometabolic, and inactive state, yet they appear to be able to return to near-normal systemic function within minutes of arousal. This study’s goal was to characterize the cardiovascular performance of overwintering black bears and elicit the underlying mechanisms enabling survival. Mid-winter cardiac electrophysiology was assessed in four wild black bears using implanted data recorders. Paired data from early and late winter were collected from 37 wild bears, which were anesthetized and temporarily removed from their dens to record cardiac electrophysiological parameters (12-lead electrocardiograms) and cardiac dimensional changes (echocardiography). Left ventricular thickness, primary cardiac electrophysiological parameters, and cardiovascular response to threats (“fight or flight” response) were preserved throughout winter. Dramatic respiratory sinus arrhythmias were recorded (cardiac cycle length variations up to 865%) with long sinus pauses between breaths (up to 13 s). The accelerated heart rate during breathing efficiently transports oxygen, with the heart “resting” between breaths to minimize energy usage. This adaptive cardiac physiology may have broad implications for human medicine.  相似文献   
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Physiological research suggests that tropical insects are particularly sensitive to temperature, but information on their responses to climate change has been lacking—even though the majority of all terrestrial species are insects and their diversity is concentrated in the tropics. Here, we provide evidence that tropical insect species have already undertaken altitude increases, confirming the global reach of climate change impacts on biodiversity. In 2007, we repeated a historical altitudinal transect, originally carried out in 1965 on Mount Kinabalu in Borneo, sampling 6 moth assemblages between 1,885 and 3,675 m elevation. We estimate that the average altitudes of individuals of 102 montane moth species, in the family Geometridae, increased by a mean of 67 m over the 42 years. Our findings indicate that tropical species are likely to be as sensitive as temperate species to climate warming, and we urge ecologists to seek other historic tropical samples to carry out similar repeat surveys. These observed changes, in combination with the high diversity and thermal sensitivity of insects, suggest that large numbers of tropical insect species could be affected by climate warming. As the highest mountain in one of the most biodiverse regions of the world, Mount Kinabalu is a globally important refuge for terrestrial species that become restricted to high altitudes by climate warming.  相似文献   
998.
We study inverse statistical mechanics: how can one design a potential function so as to produce a specified ground state? In this article, we show that unexpectedly simple potential functions suffice for certain symmetrical configurations, and we apply techniques from coding and information theory to provide mathematical proof that the ground state has been achieved. These potential functions are required to be decreasing and convex, which rules out the use of potential wells. Furthermore, we give an algorithm for constructing a potential function with a desired ground state.  相似文献   
999.
Certain beverages contribute energy, protein, vitamins, and minerals. North American adolescents have shifted their beverage intake from predominantly milk to predominantly sugary beverages. Intake of these sugary beverages, in sufficient quantity, may increase the risk of bone fractures, may contribute to obesity, and may lead to tooth decay. This study evaluated the effectiveness of a school-nutrition education program (Fluids Used Effectively for Living) on nutrition knowledge, attitude, and self-reported behavior of grade 9 students in Saskatchewan, Canada. Two classes of grade 9 students, 1 (n = 33) in a high school in Saskatoon (n = 33) and 1 (n = 24) in a large high school in Prince Albert, Saskatchewan, received the peer educator intervention. Two other classes in the 2 cities (n = 24 and n = 24, respectively) were controls. Six sessions of Fluids Used Effectively for Living nutrition education were delivered by using 2 peer educator models (multiple and single), and the intervention was delivered in a 45-minute weekly class session over a 6-week period. After the intervention, students in these 2 peer educator classes decreased their sugary beverage intake significantly, which was sustained for 3 months. Students in the control self-taught class increased their juice intake at the end of the year. The significant decrease of juice and sugary beverage intakes in the single model peer educator class disappeared after Bonferroni correction. Carbonated sugary beverage intake of students in the control self-taught classes declined, but it was not sustainable at the 3-month follow-up. A peer educator school-based nutrition education approach can lead to a decrease in sugary beverage intake in high school children.  相似文献   
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