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1.
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   
2.
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   
3.
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   
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   
5.
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   
6.
Anter  AM 肖琼 《医学教育探索》1999,(6):555-558577
在常压-2.0MPa的系统压力下测定了滴流床中气-液两相并流下流动的动持液量,了气-液流率,液相粘度,填料大小,压力以及床层高度对动持液量的影响。实验结果表明增中液体流率动持流量增加,气体流率增加时,结果相反粘度的增加对动持液量的影响不大,动持液量随填料空隙率的增大而变小。  相似文献   
7.
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   
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The authors describe the cross-cultural considerations in caring for a Palestinian breast cancer patient by an Israeli heath care team. The processes that facilitated a metamorphosis from possible hostility to receptiveness based on historical cultural conflicts were rooted in professionalism, patient-centered care, and cross-cultural sensitivity, woven into the patient’s own health beliefs and affinity to traditional Islamic medicine.  相似文献   
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