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Studies were performed in hypercholesterolemic rabbits to determine whether the hydrophobic surfactant, Poloxalene 2930 (Pol), is of benefit under these conditions. Lipoprotein analyses plus chemical and morphologic studies of the aorta were performed to evaluate the results. In one study, rabbits were made hypercholesterolemic by dietary means and then divided into two groups and given a cholesterol-free diet with one group additionally given Pol with treatment continued for 10 weeks. Pol treatment resulted in less atherosclerosis but the mechanism for this effect was not apparent from lipoprotein analysis. In the other study 3 groups of rabbits were given a cholesterol-rich diet for 16 weeks. Two groups received Pol supplement with one of these groups receiving a dose that was too small to prevent hypercholesterolemia. In this group plus the group on diet alone comparable degrees of hypercholesterolemia were maintained throughout the study. Lipoprotein abnormalities were similar in these two groups except that those on Pol had a more normal cholesterol to apolipoprotein B ratio. The amount of atherosclerosis in both groups was mild but aortic cholesterol content was much less for the Pol group. It is concluded that Pol limits cholesterol accumulation in the aortic wall of hypercholesterolemic rabbits and can retard the development of atherosclerosis.  相似文献   
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It is well known that fibroblasts are a main source of extracellular matrix synthesis necessary for tissue repair. In addition, macrophages secrete products that are known to modulate synthesis of extracellular matrix. Accordingly, we studied the incorporation of [3H]thymidine, [3H]proline, and [35S]sulfate into macromolecules produced by fibroblasts recovered from the site of peritoneal tissue repair cultured with and without spent media from postsurgical peritoneal macrophages. Rabbits underwent resection and reanastomosis of their small intestines. Peritoneal exudative cells (PEC) were then collected on postsurgical day 5 and day 10 as well as from nonsurgical controls, separated by discontinuous Percoll gradient centrifugation, and cultured for 48 h. A second group of rabbits underwent peritoneal wall abrasion from which fibroblast tissue repair cells (TRC) were collected from the site of injury at postsurgical day 7 and maintained in culture for varying times. Incorporation of radiolabeled precursors into DNA, collagen, and sulfated proteoglycans was determined. Incorporation of [3H]thymidine and [3H]proline into untreated TRC gradually decreased with culture duration. Conversely, [35S]sulfate incorporation gradually increased during prolonged culture. Macrophage spent media increased the levels of [3H]thymidine incorporation by the TRC. [3H]Proline and [35S]sulfate incorporation into TRC were also stimulated by macrophage spent media. However, this stimulation may be due to the enhanced proliferation of TRC by macrophage spent media. In conclusion, tissue repair fibroblasts are activated for postsurgical repair at the site of injury by many factors including secretory products from postsurgical macrophages.  相似文献   
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The PFA-100 is a relatively new laboratory instrument, first described in 1995. There have since been numerous studies assessing its utility as a screening tool for platelet dysfunction and/or von Willebrand's disease (VWD). The PFA-100 displays variable sensitivity to different types of platelet disorders, as well as to antiplatelet medication (e.g. aspirin), with similar caveats for monitoring of primary haemostasis-promoting therapies in platelet dysfunction. There is therefore considerable uncertainty regarding its utility within this context, and we have accordingly performed an audit of usage among participants of the Royal College of Pathologists of Australasia Quality Assurance Program. Of 105 laboratories surveyed, 40 responded that they performed platelet function testing, with 26 (65%) further indicating they utilized the PFA-100. We report a wide variety of laboratory usage among these users, including numbers of tests performed [annual median (range) = 270 (15-6000)], sources of requests (clinical sources and localities), testing criteria and follow-up action. Most tests were completed within 4 h of collection, as recommended by the manufacturer, and most tests were performed as a replacement, or as a preliminary screen of platelet function (i.e. classical aggregation). Most abnormal findings, however, were attributed to antiplatelet medication such as aspirin.  相似文献   
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A 37-year-old male with history of alcohol abuse presented to us with nausea, vomiting, and abdominal pain with ascites. He was diagnosed with alcoholic liver disease with coagulopathy and pancreatitis. During hospitalization, the patient developed intra-abdominal hemorrhage. He was treated with platelets, packed red blood cells and fresh frozen plasma without any improvement. Following this he was treated with activated recombinant factor VII (90 microg/kg), which resulted in normalization of the prothrombin time and the activated partial thromboplastin time and stabilization of hematocrit within a few hours. We review the current literature on the approved and off-label use of activated recombinant factor VII.  相似文献   
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Turndowns of offers of deceased donor kidneys for transplantation can contribute to inefficiencies in the organ distribution system and inequality in access to donated organs. Match run data were obtained for 4967 'good' kidneys placed and transplanted in 2005 after fewer than 50 offers. These kidneys were not recovered from donation after cardiac death or expanded criteria donors, or from donors with a history of substance abuse. On average, these good kidneys were not accepted until after seven offers to candidates and after offers to 2.4 programs. Models for the likelihood of acceptance found several donor and candidate characteristics to be significantly related to acceptance rates (p < 0.05). After accounting for these variables, there remained 2- to 3-fold differences among transplant programs in acceptance rates. These models could be used to identify kidney transplant centers with exceptional acceptance practices. Several strategies might be employed to increase acceptance rates for good organs.  相似文献   
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BACKGROUND: Patients on hormone replacement therapy (HRT) for osteoporosis prevention rather than menopausal symptom control may be asymptomatic, despite inadequate replacement and low serum oestradiol (E2) levels. In the primary health care setting, therapeutic monitoring of HRT is not carried out routinely so that patients with serum E2 levels inadequate to protect bone may be missed. AIM: To determine the proportion of women on transdermal E2 preparations with serum E2 levels insufficient to protect bone and to assess the value of a questionnaire-derived menopausal symptom score (MSS) for detecting these patients. METHOD: A cross-sectional analysis of 45 patients aged 35-70 years using transdermal E2 preparations obtained from a computer register of 14500 patients in a suburban practice. One blood sample was obtained from each patient at the time the MSS questionnaire was completed. Serum E2 concentration was measured using a fluoroimmunoassay and compared with the MSS. Levels below 150 pmol/l were considered to be insufficient to protect bone. The diagnostic accuracy of the MSS in screening for levels below 150 pmol/l was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: The median (95% CI) serum E2 was 147 pmol/l (126-198 pmol/l) and levels were below 150 pmol/l in 24 out of 45 patients. There was no difference in the MSS (median, 95% CI) between those with serum E2 < 150 pmol/l (8.5, 5.0-17) and > or = 150 pmol/l (9.0, 5.0-14; P = 0.477). The degree of association between the serum E2 and the MSS, using the Spearman rank correlation coefficient, rs (95% CI) was small and not significant (-0.04, -0.34 to 0.26; P = 0.398). ROC curve analysis revealed an area under the curve (95% CI) of 0.51 (0.33-0.68). CONCLUSIONS: More than half the women were inadequately replaced to protect against osteoporosis. Furthermore, the MSS was of no value in screening for those with low serum E2 levels. Serum E2 levels should be monitored in women on HRT for osteoporosis prevention and the E2 dosage adjusted accordingly.  相似文献   
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AD  Giannoukas  N  Labropoulos  FCT  Smith  GS  Venables  JD  Beard  武婕 《中华脑血管病论坛》2005,3(5):555-560
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章.  相似文献   
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