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Premature ovarian failure   总被引:9,自引:0,他引:9  
Premature ovarian failure (POF) causing hypergonadotrophic hypogonadism occurs in 1% of women. In majority of cases the underlying cause is not identified. The known causes include: (a) Genetic aberrations, which could involve the X chromosome or autosomes. A large number of genes have been screened as candidates for causing POF; however, few clear causal mutations have been identified. (b) Autoimmune ovarian damage, as suggested by the observed association of POF with other autoimmune disorders. Anti-ovarian antibodies are reported in POF by several studies, but their specificity and pathogenic role are questionable. (c) Iatrogenic following surgical, radiotherapeutic or chemotherapeutic interventions as in malignancies. (d) Environmental factors like viral infections and toxins for whom no clear mechanism is known. The diagnosis is based on finding of amenorrhoea before age 40 associated with FSH levels in the menopausal range. Screening for associated autoimmune disorders and karyotyping, particularly in early onset disease, constitute part of the diagnostic work-up. There is no role of ovarian biopsy or ultrasound in making the diagnosis. Management essentially involves hormone replacement and infertility treatment, the only proven means for the latter being assisted conception with donated oocytes. Embryo cryopreservation, ovarian tissue cryopreservation and oocyte cryopreservation hold promise in cases where ovarian failure is foreseeable as in women undergoing cancer treatments.  相似文献   
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Foreign bodies in the esophagus are commonly seen in otolaryngologic practice. We report the successful removal of a working wrist watch dial lodged for one month in the esophagus of an adult schizophrenic patient, which is a rare incident.  相似文献   
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Coumarins and coumestans represent an important family of compounds with diverse pharmacological properties. We recently identified coumestans as novel inhibitors of hepatitis C virus NS5B polymerase and predicted their binding in thumb pocket‐1 (TP‐1) of NS5B. As the coumarins are structurally related to coumestans by virtue of their common A‐ and B‐rings, we postulated them to also exhibit similar binding interaction with NS5B and inhibit its polymerase function. We therefore investigated 24 coumarin and neoflavone derivatives as candidate NS5B inhibitors and identified 14 compounds inhibiting NS5B polymerase activity with IC50 values between 17 and 63 μm . Of these, the newly synthesized 6,8‐diallyl‐5,7‐dihydroxycoumarin ( 8a ) was produced in three steps in high chemical yield from floroglucinol and found to be the most potent of this series, exhibiting activity similar to the reference coumestan LQB‐ 34 . The binding site of 8a was mapped to TP‐1 of NS5B by counter screening against P495L NS5B mutant, employed as a screen for TP‐1 site binders. NS5B‐TP‐1‐ 8a interaction map provided insight into 8a binding and offered clues for future SAR optimization.  相似文献   
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IntroductionThe variable course of illness in patients of Tubercular lymphadenitis remains a therapeutic challenge to treating physicians in a significant proportion of patients. This study was aimed to explore the possible determinants which could predict the outcome of this subgroup of patients.MethodologyThis was a prospective cohort study where 94 patients of TB lymphadenitis were enrolled who could be followed up till the end of treatment. They were evaluated in the beginning and monitored till the end of treatment keeping into account the clinical behaviour of lymph nodes during the course of Anti tubercular chemotherapy.ResultsOut of 94 patients, 60 had their lymph nodes resolved at the end of prescribed treatment duration wheras 34 were classified as partial responders. Another 26 amongst them had their nodes resolved by an extension of continuation phase by 3–6 months. Presence of bilateral and multiple lymph nodes, necrosis on Fine needle aspiration at initial diagnosis and occurrence of Paradoxical upgrading reaction were associated with the partial resolution of lymph nodes at the end of stipulated ATT duration.ConclusionTreatment duration should be individualized by the treating physicians. Certain parameters mentioned above can be taken as warning signals of patients ending up as partial responders and hence the need of a prolonged extension phase.  相似文献   
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We identified and characterized enteroviruses associated with aseptic meningitis in children between April 2009 and March 2010. Enterovirus RNA was detected in 51 (45.5 %) of 112 CSF samples. Molecular typing by RT-PCR and sequencing of a partial VP1 region revealed the predominance of echovirus (ECV) 32 (n = 20), followed by ECV 11 (n = 10), ECV 13 and ECV 14 (n = 5 each), coxsackievirus (CV) B3 and CV B6 (n = 3 each), CV A2, CV A10 and ECV 30 (n = 1 each). Phylogenetic analysis of ECV 32 showed 0 to 4 % sequence divergence among strains of the present study and 20-23 % from the prototype Puerto Rico strain at the nucleotide level. This is the first report of ECV 32 associated with an aseptic meningitis epidemic and identification of seven different enterovirus serotypes (CV A2, CV A10, CV B3, CV B6, ECV 13, ECV 14 and ECV 32) in meningitis cases from India.  相似文献   
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This special issue addresses access to and service delivery of assistive technology (AT) in resource-limited environments (RLEs). Access to AT is complicated not simply by limited funds to purchase AT, but by larger ecosystem weaknesses in RLEs related to legislation and policy, supply, distribution, human resources, consumer demand and accessible design. We present eight diverse articles that address various aspects of the AT ecosystem. These articles represent a wide range of AT, many different countries and different research methods. Our goal is to highlight a topic that has received scant research investigation and limited investment in international development efforts, and offer an insight into how different countries and programs are promoting access to AT. We encourage researchers, funders and non-profit organizations to invest additional effort and resources in this area.  相似文献   
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