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11.
A case is described in which a patient, who initially presented with five separate bladder calculi, was found to have had coalescence of three calculi to produce a large stone. This may be one mechanism in the development of a giant vesical calculus.  相似文献   
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Abel Garcia-Garcia 《Journal of oral and maxillofacial surgery》2005,63(5):723; author reply 723-723; author reply 724
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The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5–1 mg/ml it increased the L-type Ca current (ICaL) by 25–50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1–10 mg/ml). In this concentration range, Bainh markedly (≈75%) increased the inward-going rectifier current, IK1. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations.  相似文献   
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Gallbladder dyskinesia in chronic acalculous cholecystitis   总被引:4,自引:0,他引:4  
To test the hypothesis that there is an early stage of cholesterol gallstone formation in man characterized by symptoms of chronic cholecystitis, poor gallbladder emptying, and biliary cholesterol crystals, we studied cholecystokinin-stimulated gallbladder emptying by DISIDA scintigraphy and examined bile for cholesterol crystals in symptomatic patients with normal oral cholecystography and gallbladder sonography. Of 36 patients studied, 16 had biliary cholesterol crystals; their mean 30-min gallbladder ejection fraction was 25.9±14.8%. Among the 20 patients without crystals, the mean ejection fraction was 60.3±23.3%. Fifteen patients, 11 with crystals and four without, had cholecystectomy because of persistent symptoms. All with crystals preoperatively and three without had chronic cholecystitis histologically. One patient without crystals had normal histology. We conclude that poor gallbladder contractility, well-established as an etiologic factor in animal models of cholesterol cholelithiasis, is now linked to acalculous cholecystitis, an early stage of human cholesterol cholelithiasis.  相似文献   
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OBJECTIVE: To assess age and symptom experience at menopause in a high-altitude population in the Selska Valley of Slovenia. DESIGN: In four mountain villages, all houses were approached and 80% of eligible residents were interviewed. Additional women were interviewed for comparison in the valley below. Age at interview ranged from 32.7 to 85.5 years, with a mean of 58.2 years. The majority of women (62%) were aged 40 to 65 years. RESULTS: Of the 58 women interviewed, 7 had undergone menopause by hysterectomy (12%). Recalled age at natural menopause ranged from 42 to 54, with a mean of 50.3 (SD 2.9). By probit analysis, median age at natural menopause was 52.03. Fifty-five percent of participants reported ever having experienced a hot flash, although only 24% reported hot flashes during the 2 weeks before being interviewed. When the sample was limited to women aged 40 to 65, frequency of hot flashes in the 2 weeks before the interview was 39%. For all participants, the most frequent complaint was lack of energy (66%), followed by backaches (59%), and joint stiffness (53%). CONCLUSIONS: In contrast to expectations, age at menopause was not earlier and hot flash frequency was not significantly lower at higher elevations.  相似文献   
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miRNPs: a novel class of ribonucleoproteins containing numerous microRNAs   总被引:44,自引:0,他引:44  
Gemin3 is a DEAD-box RNA helicase that binds to the Survival of Motor Neurons (SMN) protein and is a component of the SMN complex, which also comprises SMN, Gemin2, Gemin4, Gemin5, and Gemin6. Reduction in SMN protein results in Spinal muscular atrophy (SMA), a common neurodegenerative disease. The SMN complex has critical functions in the assembly/restructuring of diverse ribonucleoprotein (RNP) complexes. Here we report that Gemin3 and Gemin4 are also in a separate complex that contains eIF2C2, a member of the Argonaute protein family. This novel complex is a large approximately 15S RNP that contains numerous microRNAs (miRNAs). We describe 40 miRNAs, a few of which are identical to recently described human miRNAs, a class of small endogenous RNAs. The genomic sequences predict that miRNAs are likely to be derived from larger precursors that have the capacity to form stem-loop structures.  相似文献   
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Journal of Clinical Immunology - The objective of this study was to characterize interleukin-1 receptor antagonist (IL-1ra) and interleukin-1β (IL-1β) production by human peripheral blood...  相似文献   
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Exudates from non-healing wounds contain elevated levels of proteolytic enzymes, like elastase from polymorphonuclear granulocytes (PMN elastase), reactive oxygen species (ROS) and reactive nitrogen species (RNS). The overproduction of proteolytic enzymes leads to reduced concentrations of growth factors and proteinase inhibitors, resulting in an imbalance between degradation and remodelling processes. Thus, the reduction of protein-degrading enzymes and scavenging of ROS and RNS seem to be suitable ways to support the healing process of chronic stagnating wounds. The aim of this study was to test selected wound dressings from different biomaterials (collagen, oxidized regenerated cellulose (ORC) and ORC/collagen mixture), regarding their antioxidative potential in vitro and their influence on the concentration and activity of PMN elastase in chronic wound fluid. Antioxidant capacity of the investigated wound dressing was determined by a pholasin-based chemiluminescent assay. PMN elastase concentration was determined by means of ELISA. Enzyme activities could be measured by a fluorescence assay. As the presented data demonstrates, all tested materials showed antioxidant capacity. In addition, the investigated materials were able to reduce the concentration and activity of PMN elastase. Beside other aspects, such as biocompatibility, biodegradability, fluid absorption and clinical effects (e.g. angiogenesis and microcirculation), the understanding of these properties may help to support the further refinement of wound dressings for improved wound healing.  相似文献   
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