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971.
Parachute tricuspid valve is a rare anomaly usually reported in small children. This report describes transthoracic and trans-oesophageal echocardiographic (TEE) features of parachute mitral valve in an adult patient.  相似文献   
972.
To assess the medico social demographics of acute myocardial infarction (AMI) in our community we studied 609 patients presenting between January 2008 to December 2008 with a detailed questionnaire in four centres of UP. Medical attention was sought late (> 6 hours) in 316 (51.6%), thrombolysis was obtained in 45.2% (275) and presentation was atypical in 16.3% (99). 36.2% (221) had pre-monitory symptoms of which 68% (150) ignored the same while of 32% (71) who did seek medical attention 47.9% (37) were brushed away as non-cardiac in origin. 20.3% (46/226) of hypertension, 23.2% (43/185) of diabetes and 83.4% (91/109) of hyperlipidaemia was diagnosed post event. We conclude that at least half of patients with AMI do not get definitive therapy, at least one in 10 patients do not have the classical symptoms, reasonable proportion are unaware of their risk factors, and a good majority have pre-monitory symptoms which get overlooked.  相似文献   
973.
974.
This study investigated the role of urocortin (UCN), a member of the corticotrophin-releasing factor (CRF) family of peptides, in osteoclast maturation and function. We found that 10(-7)?M UCN significantly (P<0.05) suppressed osteoclast differentiation from bone marrow precursor cells in culture and reduced the expression of several osteoclastic markers. Furthermore, UCN potently suppressed osteoclast bone resorption, by significantly inhibiting both the plan area of bone resorbed by osteoclasts and actin ring formation within osteoclasts at 10(-9)?M (P<0.05), with complete inhibition at 10(-7)?M (P<0.001). UCN also inhibited osteoclast motility (10(-7)?M) but had no effect on osteoclast survival. Osteoclasts expressed mRNA encoding both UCN and the CRF receptor 2β subtype. Pre-osteoclasts however, expressed CRF receptor 2β alone. Unstimulated osteoclasts contained constitutively active cation channel currents with a unitary conductance of 3-4?pS, which were inhibited by over 70% with UCN (10(-7)?M). Compounds that regulate calcium signalling and energy status of the cell, both crucial for osteoclast activity were investigated. The non-selective cation channel blockers, lanthanum (La(3)(+)) and gadolinium (Gd(3)(+)), inhibited actin ring formation in osteoclasts, whereas modulators of voltage-dependent Ca(2)(+) channels and K(ATP) channels had no effect. These findings show for the first time that UCN is a novel anti-resorptive molecule that acts through a direct effect on osteoclasts and their precursor cells.  相似文献   
975.
There is a critical need for improved diagnosis of tuberculosis in children, particularly in young children with intrathoracic disease as this represents the most common type of tuberculosis in children and the greatest diagnostic challenge. There is also a need for standardized clinical case definitions for the evaluation of diagnostics in prospective clinical research studies that include children in whom tuberculosis is suspected but not confirmed by culture of Mycobacterium tuberculosis. A panel representing a wide range of expertise and child tuberculosis research experience aimed to develop standardized clinical research case definitions for intrathoracic tuberculosis in children to enable harmonized evaluation of new tuberculosis diagnostic technologies in pediatric populations. Draft definitions and statements were proposed and circulated widely for feedback. An expert panel then considered each of the proposed definitions and statements relating to clinical definitions. Formal group consensus rules were established and consensus was reached for each statement. The definitions presented in this article are intended for use in clinical research to evaluate diagnostic assays and not for individual patient diagnosis or treatment decisions. A complementary article addresses methodological issues to consider for research of diagnostics in children with suspected tuberculosis.  相似文献   
976.
977.
ObjectiveSerum lipoprotein is the most important predictor for microvascular diseases, and may be influenced by rapid urbanization. Currently available data are limited, particularly regarding age-specific lipoprotein status in urban Bangladeshi populations.MethodsBlood lipoprotein levels of 51,353 male and female individuals primarily residing in urban Bangladesh were analyzed. De-identified data (collected between January 2005 and December 2011) were extracted from the Clinical Biochemistry Laboratory Data Archive of International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). For analyses, six age categories were created: (i) <20 years, n = 481; (ii) 20–29 years, n = 1602; (iii) 30–39 years, n = 7272; (iv) 40–49 years, n = 13,582; (v) 50–59 years, n = 15,890; and (vi) 60 years and more, n = 12,526.ResultsMean serum levels of TC, LDL, TG, LDL:HDL and TC:HDL were significantly higher among adults 30–39 years old compared to other age groups, regardless of sex. The proportion of high TC and LDL from 2005 to 2011 among individuals aged 30–39 years old varied widely (p < 0.01 for trend and all pairwise tests).Conclusion30–39 years old individuals had higher concentration of lipoprotein, which increases microvascular disease risk. Further population-based studies are needed to validate our observations in rural areas of Bangladesh.  相似文献   
978.
979.
980.
A chemically diverse family of small-molecule signals, the ascarosides, control developmental diapause (dauer), olfactory learning, and social behaviors of the nematode model organism, Caenorhabditis elegans. The ascarosides act upstream of conserved signaling pathways, including the insulin, TGF-β, serotonin, and guanylyl cyclase pathways; however, the sensory processes underlying ascaroside function are poorly understood. Because ascarosides often are multifunctional and show strongly synergistic effects, characterization of their receptors will be essential for understanding ascaroside biology and may provide insight into molecular mechanisms that produce synergistic outcomes in small-molecule sensing. Based on DAF-8 immunoprecipitation, we here identify two G-protein-coupled receptors, DAF-37 and DAF-38, which cooperatively mediate ascaroside perception. daf-37 mutants are defective in all responses to ascr#2, one of the most potent dauer-inducing ascarosides, although this mutant responds normally to other ascarosides. In contrast, daf-38 mutants are partially defective in responses to several different ascarosides. Through cell-specific overexpression, we show that DAF-37 regulates dauer when expressed in ASI neurons and adult behavior when expressed in ASK neurons. Using a photoaffinity-labeled ascr#2 probe and amplified luminescence assays (AlphaScreen), we demonstrate that ascr#2 binds to DAF-37. Photobleaching fluorescent energy transfer assays revealed that DAF-37 and DAF-38 form heterodimers, and we show that heterodimerization strongly increases cAMP inhibition in response to ascr#2. These results suggest that that the ascarosides' intricate signaling properties result in part from the interaction of highly structure-specific G-protein-coupled receptors such as DAF-37 with more promiscuous G-protein-coupled receptors such as DAF-38.  相似文献   
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