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排序方式: 共有809条查询结果,搜索用时 31 毫秒
1.
Ophira Salomon Joseph Moisseiev Tamara Vilganski Rima Dardik Shimon Kurtz Eva Shpringer David M Steinberg Nurit Rosenberg 《Blood coagulation & fibrinolysis》2006,17(6):485-488
To determine whether polymorphisms of platelet surface glycoprotein associated with arterial thrombosis are risk factors for branch retinal vein occlusion. A case-control study in which 69 patients with branch retinal vein occlusion and 147 controls who attended the eye clinic for nonvascular complications participated. DNA was extracted from whole blood and analyzed for genotyping of platelet glycoprotein polymorphisms by polymerase chain reactions and specific restricted enzymes. No relationship was found between the four platelet glycoprotein polymorphisms i.e. GPIa C807T, VNTR and Kozak of glycoprotein Ibalpha, the HPA-1 of glycoprotein IIIa and the occurrence of branch retinal vein occlusion. The HPA-2 polymorphism was found in 18 out 60 (30%) patients with branch retinal vein occlusion in comparison with 27 out 142 (19%) of controls, with an estimated odds ratio of 1.8 (95% confidence interval, 0.91-3.65). The four platelet glycoprotein polymorphisms are not risk factors for branch retinal vein occlusion and therefore it seems unnecessary to screen those patients for it. A larger study is required, however, to determine whether HPA-2 is a novel risk factor for branch retinal vein occlusion. 相似文献
2.
Blood flowing through a prosthetic heart valve can be damaged by flow-induced shear forces. Fluid dynamics variables and geometric factors play an important role in the evaluation of shear-stress-related blood damage. Central-flow prosthetic valves have been considered as an optimal replacement for mechanical and biological valves. Recently it was shown that shear stress distribution along the surface of a polyurethane cusp reaches values that can damage the blood elements. A mathematical model correlating the effects of shear stresses on blood corpuscles with clinical findings was employed in vitro. The model can be applied to the effects of blood-surface interaction and is of clinical relevance. 相似文献
3.
J Moisseiev H Lewis E Bartov S L Fine R P Murphy 《American journal of ophthalmology》1990,109(5):604-605
4.
Retinal pigment epithelium cells can influence endothelial cell plasminogen activators 总被引:2,自引:0,他引:2
J Moisseiev J A Jerdan K Dyer A Maglione B M Glaser 《Investigative ophthalmology & visual science》1990,31(6):1070-1078
Endothelial cells from both human retinal microvessels (HME) and fetal bovine aortic endothelium (FBAE) were grown in aggregate cultures alone, or with either retinal pigment epithelium (RPE) cells or fibroblasts. The levels of plasminogen activator (PA) and plasminogen activator inhibitor (PAI) in the conditioned media of the various aggregate types were measured. High PA levels were detected in the conditioned medium of pure endothelial cell aggregates (equal to 140% and 124% of urokinase control for HME and FBAE, respectively), and high PAI levels were associated with pure RPE aggregates (inhibiting 93% of the urokinase control). The conditioned medium of pure fibroblast aggregates had very low levels of either PA or PAI. When RPE cells were aggregated with FBAE or HME cells into mixed (heterogenous) aggregates, the PA measured in the conditioned medium was equal to 22% and 30% of the urokinase control, respectively. The PA level in the conditioned medium of mixed fibroblast-FBAE cell aggregates was higher, 104% of the control, and the difference was statistically significant (P less than 0.001). Co-incubation of pure RPE aggregates with pure FBAE aggregates or with pure HME aggregates resulted in PA activity in the conditioned medium that was equal to 110% and 96% of the control, respectively. The PA level found when pure FBAE cell aggregates were co-incubated with pure fibroblast aggregates was higher, 134% of the control, and the difference was statistically significant (P less than 0.001). Our results indicate that RPE cells can reduce endothelial cell PA, probably through both direct contact between the cells and PAI production. Fibroblasts did not have this influence on endothelial cell PA. 相似文献
5.
Elad D Yas-Natan E Aroch I Shamir MH Kleinbart S Hadash D Chaffer M Greenberg K Shlosberg A 《Journal of clinical microbiology》2004,42(11):5406-5408
Clinical signs of botulism were observed in a group of eight cats, four of which died, after being fed pelican carrion. Clostridium botulinum type C was isolated from one cat. The microorganism and its toxin were found in the pelican. This is apparently the first report of natural botulism in cats. 相似文献
6.
D Elad I Aizenberg M Shamir F Soriano S Shlomovitz 《Journal of clinical microbiology》1992,30(5):1167-1169
Corynebacterium group D2 was isolated from two dogs with urinary tract infections. The isolates were resistant in vitro to all tested antibacterial drugs except vancomycin. One dog was successfully treated with this antibiotic, while the other died before treatment could be initiated. 相似文献
7.
Thaísa Agrizzi Verediano Hrcia Stampini Duarte Martino Maria Cristina Dias Paes Elad Tako 《Nutrients》2021,13(4)
Intestinal health relies on the association between the mucosal immune system, intestinal barrier and gut microbiota. Bioactive components that affect the gut microbiota composition, epithelial physical barrier and intestinal morphology were previously studied. The current systematic review evaluated evidence of anthocyanin effects and the ability to improve gut microbiota composition, their metabolites and parameters of the physical barrier; this was conducted in order to answer the question: “Does food source or extract of anthocyanin promote changes on intestinal parameters?”. The data analysis was conducted following the PRISMA guidelines with the search performed at PubMed, Cochrane and Scopus databases for experimental studies, and the risk of bias was assessed by the SYRCLE tool. Twenty-seven studies performed in animal models were included, and evaluated for limitations in heterogeneity, methodologies, absence of information regarding allocation process and investigators’ blinding. The data were analyzed, and the anthocyanin supplementation demonstrated positive effects on intestinal health. The main results identified were an increase of Bacteroidetes and a decrease of Firmicutes, an increase of short chain fatty acids production, a decrease of intestinal pH and intestinal permeability, an increase of the number of goblet cells and tight junction proteins and villi improvement in length or height. Thus, the anthocyanin supplementation has a potential effect to improve the intestinal health. PROSPERO (CRD42020204835). 相似文献
8.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society.
PAC2003: 8719-j, 8710+e 相似文献
9.
Neoadjuvant chemotherapy does not increase postoperative complication rate after resection of colorectal liver metastases. 总被引:2,自引:0,他引:2
S Yedibela L Elad A Wein A Dimmler S Merkel W Hohenberger T Meyer 《European journal of surgical oncology》2005,31(2):141-146
BACKGROUND: This paper discusses, whether neoadjuvant chemotherapy has an impact on the rate of postoperative complications after primary resection of liver metastases from colorectal carcinoma. METHODS: Of 183 patients 64 were studied. The patients were subdivided into two matched groups of 32 patients each-prior neoadjuvant chemotherapy (CT-group) vs. (control-group, primary resection). RESULTS: There were no postoperative complications in 24 patients of the control group (75%) and 26 patients of the CT-group (81%). Following prior chemotherapy, no major complications such as liver failure were observed, even after extended resections. CONCLUSION: Neoadjuvant chemotherapy prior to surgical resection of colorectal liver metastases does not result in an increase of postoperative morbidity and mortality. 相似文献