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171.
Daniel H Steinberg Lowell F Satler Augusto D Pichard 《Catheterization and cardiovascular interventions》2007,70(2):241-243
Retrieval of intravascular objects can be accomplished through snare retrieval. We report a case in which a patient presented with symptomatic in-stent restenosis caused by a fractured aorto-ostial sirolimus-eluting stent in a saphenous vein graft. Because of the inability to selectively engage the stent ostium with the guide catheter, the fractured stent was removed with an endovascular snare in order to permit successful revascularization. With the proximal portion of the stent retrieved by the snare, a new stent was implanted without complication. 相似文献
172.
The Gay Bowel Syndrome 总被引:4,自引:0,他引:4
NORMAN SOHN M.D. F.A.C.S. F.A.C.G. JAMES G. ROBILOTTI JR. M.D. F.A.G.G. 《The American journal of gastroenterology》1977,67(5):478-484
Our experience in the management of 260 male homosexuals with coloreetal problems is described. The increased incidence of amebiasis, shigellosis and hepatitis, specific and nonspecific protocolitides, venereal disease and anal warts, is emphasized. It is important to recognize homosexual patients and the conditions to which they are predisposed. 相似文献
173.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts 总被引:2,自引:0,他引:2
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction. 相似文献
174.
Experimental specification of cell sorting, tissue spreading, and specific spatial patterning by quantitative differences in cadherin expression. 总被引:15,自引:0,他引:15 下载免费PDF全文
M S Steinberg M Takeichi 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(1):206-209
The sorting-out of embryonic cells from a cell mixture and the selective spreading of one cell population over the surface of another have been attributed to various causes. These include differentials in chemotaxis, in cellular adhesiveness, in cell surface contractility, in speed of cell movement, and in the timing of postulated changes in cellular adhesive and motile properties. One of us earlier predicted on mathematical grounds that two motile cell types differing only in the level of expression of a single cell adhesion system should not only segregate from one another but also arrange themselves with the less cohesive cells enveloping a core of the more cohesive ones. To test these predictions, we combined two populations of L cells transfected with P-cadherin cDNA and expressing this homophilic adhesion molecule in substantially differing amounts. When the two cell populations were intermixed, they segregated to approach a sphere-within-a-sphere configuration, the cell population expressing more P-cadherin forming islands which fused to become an internal "medulla." When the two cell populations were first formed into separate aggregates which were subsequently allowed to fuse, the cell population expressing more P-cadherin was enveloped by its partner, which formed an external "cortex." These observations confirm the early prediction and support the conclusion that both morphogenetic movements and the specific anatomical configurations to which they lead can be determined by particular sets of intercellular adhesive intensities, regardless of how these are generated and in the absence of differentials in other parameters. 相似文献
175.
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178.
Liangsuo Ma Joel L. Steinberg Khader M. Hasan Ponnada A. Narayana Larry A. Kramer F. Gerard Moeller 《Human brain mapping》2014,35(3):760-778
Although reduced working memory brain activation has been reported in several brain regions of cocaine‐dependent subjects compared with controls, very little is known about whether there is altered connectivity of working memory pathways in cocaine dependence. This study addresses this issue by using functional magnetic resonance imaging‐based stochastic dynamic causal modeling (DCM) analysis to study the effective connectivity of 19 cocaine‐dependent subjects and 14 healthy controls while performing a working memory task. Stochastic DCM is an advanced method that has recently been implemented in SPM8 that can obtain improved estimates, relative to deterministic DCM, of hidden neuronal causes before convolution with the hemodynamic response. Thus, stochastic DCM may be less influenced by the confounding effects of variations in blood oxygen level‐dependent response caused by disease or drugs. Based on the significant regional activation common to both groups and consistent with previous working memory activation studies, seven regions of interest were chosen as nodes for DCM analyses. Bayesian family level inference, Bayesian model selection analyses, and Bayesian model averaging (BMA) were conducted. BMA showed that the cocaine‐dependent subjects had large differences compared with the control subjects in the strengths of prefrontal–striatal modulatory (B matrix) DCM parameters. These findings are consistent with altered cortical–striatal networks that may be related to reduced dopamine function in cocaine dependence. As far as we are aware, this is the first between‐group DCM study using stochastic methodology. Hum Brain Mapp 35:760–778, 2014. © 2012 Wiley Periodicals, Inc. 相似文献
179.
Doron Steinberg Lana Eskander Avraham Zini Harold Sgan-Cohen Musa Bajali 《Clinical oral investigations》2014,18(3):979-983
Objectives
The aim of the present study was to investigate the distribution of oral cariogenic bacteria among 12-year-old Palestinian children attending schools in East Jerusalem.Materials and methods
Salivary levels of mutans streptococci (MS) and Lactobacilli (LB) were examined by semi-quantitative commercial kits and then correlated to social–demographic parameters.Results
Overall, 52.1 % of the examined children presented the highest possible ranking score categories for MS bacteria, with only 5.4 % in the lowest category. Only 12.6 % of the school children presented the highest LB score, while 25 % had the lowest ranking score. Salivary MS levels in children attending private schools were lower than those of children in government schools and United Nations Relief and Works Agency (UNRWA) schools. Conversely, levels of LB were lowest in children attending UNRWA schools compared to government and private schools. Girls had significantly higher amounts of MS and LB than boys (p?=?0.001). Lower MS levels were significantly related to the following socioeconomic variables: higher father’s education level (p?=?0.037), higher mother’s education level (p?=?0.063), mother’s employment status (p?=?0.012), and lower home density (p?=?0.001). For LB, the only significant socioeconomic variable was higher father’s employment level, which was related to lower LB level (p?=?0.025).Conclusions
Levels of MS and LB were found to be strongly related with socioeconomic status among Palestinian children in East Jerusalem. The relatively high prevalence of cariogenic bacteria suggests that oral care prevention and treatment demands special attention from the health care institutions and authorities. 相似文献180.
Paul V. Browne Deane F. Mosher Martin H. Steinberg Robert P. Hebbel 《American journal of hematology》1996,51(4):296-301
Thrombospondin (TSP), a large protein found in platelet α-granules (as TSP-1), mediates adhesion of sickle reticulocytes to cultured vascular endothelium. To further explore the physiologic relevance of this observation, we have measured plasma TSP levels and platelet TSP-1 content in subjects with sickle cell disease. Plasma TSP levels were similar for normal controls (mean 491 ng/ml, range 331–723) and steady-state HbSS patients (mean 536, range 333–1107) and were significantly (P = 0.012) but variably elevated for HbSS patients presenting with acute painful crisis (mean 868, range 442–2780). Some of these elevated plasma TSP levels reached those previously observed to support maximal red cell adhesion to endothelium in vitro. Compared to normals, both steady-state and in-crisis HbSS patients had significantly (P < 0.001) depressed platelet TSP-1 content (82.6 ± 11.9, 47.1 ± 16.0 and 45.9 ± 20.7 ng/109 platelets, respectively, mean ± SD). HbSC disease patients, all examined during steady state, had low-normal plasma levels of TSP and either normal or depressed platelet TSP-1 content. Serial observations on three sickle cell anemia subjects indicated a probable relationship between platelet TSP-1 release, elevated plasma TSP levels, and acute vasoocclusive episodes. These results suggest a state of ongoing release and depletion of TSP-1 from activated platelets in patients with sickle cell disease. © 1996 Wiley-Liss, Inc. 相似文献