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排序方式: 共有1514条查询结果,搜索用时 15 毫秒
41.
CHENGGANG YI MD YONG PAN MD YAN ZHEN MM LINXI ZHANG MD XUDONG ZHANG MD MAOGUO SHU MD YAN HAN MD SHUZHONG GUO MD 《Dermatologic surgery》2006,32(12):1437-1443
BACKGROUND: A recent discovery showed that endothelial progenitor cells (EPCs) could augment collateral vessel growth to ischemic tissues. OBJECTIVE: The objective was to demonstrate the effects of EPCs on the vasculogenesis and survival of free transplanted fat tissues in nude mice. METHODS: EPCs from human donors were cultured in vitro for 7 days. Human fat tissues were injected subcutaneously into the scalps of 20 6-week-old nude male mice. EPCs stained with CM-DiI were mixed with the transplanted fat tissues and injected into the mice. EBM-2 medium was used as control group. The animals were euthanized 15 weeks after the procedure. Graft volume were measured, and histologic evaluation was performed. The central part of fat tissues was histologically evaluated 15 weeks after the fat injection. RESULTS: The survival volume of the experimental group was significantly greater than that of the control group (p< .05). Less cyst formation and fibrosis was obtained in the experimental group. Histologic evaluation of the central part of fat tissues 15 weeks after the fat injection showed that capillary densities increased markedly in the experimental group mice. CONCLUSION: The results indicate that EPCs have the ability to enhance the survival and the quality of the transplanted fat tissues. 相似文献
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Zhaoxia LiuChunsheng Li MM Junyuan WuCaijun Wu MM Guichen Zhang MM 《The Journal of emergency medicine》2011
Background: Restoration of spontaneous circulation after cardiopulmonary resuscitation in cardiac arrest patients does not always signal a completely successful outcome. Functional deficiencies of the nervous system are found in many survivors of cardiac arrest. Objectives: To study the effects of dopamine-induced elevated blood pressure on the hemodynamics, oxygen metabolism, and cerebral resuscitation in different perfusion conditions in a resuscitated animal model. Methods: There were 18 pigs included in the study. Ventricular fibrillation (VF) was induced with a programmed electrical stimulation device. After 4 min of untreated ventricular fibrillation followed by 9 min of CPR, 12 animals were resuscitated successfully, and were then randomly assigned to either the study group (dopamine group) or the control group (normal perfusion group). All animals in the two groups received normal saline through continuous intravenous guttae for 4 h at a rate of 15 mL/kg/h. In the study group, dopamine was added to raise the animals' blood pressure. Four hours of intensive monitoring was performed for all study animals. Finally, 24-h evaluation of neurological function was conducted in surviving animals in accordance with the standard of the Cerebral Performance Category Score. Results: In animals in the dopamine group, the cardiac output, mean aortic pressure, coronary perfusion pressure, oxygen delivery, and oxygen consumption were higher than those found in the animals in the normal perfusion group (p < 0.05). Oxygen metabolism was remarkably improved in animals in the dopamine group. Furthermore, cerebral perfusion was better in the dopamine group than in the control group and thus, results of the evaluation of nervous system function were better in animals treated with dopamine (p < 0.05). Conclusions: Dopamine improved systemic perfusion, cerebral blood supply, and oxygen metabolism after successful resuscitation from VF in a porcine model. All of these factors have profound effects on the cerebral resuscitation. 相似文献
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Epstein-Barr virus lymphoproliferation after bone marrow transplantation 总被引:16,自引:7,他引:16
We review 15 cases of secondary B-cell lymphoproliferative disorders that occurred among 2,475 patients who received allogeneic bone marrow transplants (BMTs) at the Fred Hutchinson Cancer Research Center (Seattle) between 1969 and 1987. The histopathologic findings in 14 of the 15 patients spanned a wide spectrum of lymphoproliferative lesions. One patient had features characteristic of angioimmunoblastic lymphadenopathy. Epstein-Barr virus (EBV) genomic sequences were identified by Southern blot analysis in each of the 13 patients evaluated. Ten of the 12 lesions evaluated originated in donor cells. In two patients, who had mixed chimerism after transplantation, the lesions originated in host cells. The combined evidence from immunoglobulin light chain staining and the analysis of immunoglobulin heavy chain gene rearrangement indicated that the lesions in most patients represented polyclonal proliferations that gave rise to clonal subpopulations. The results indicate an overall actuarial incidence of 0.6% for this complication in BMT recipients. Anti-CD3 monoclonal antibody (MoAb) treatment of acute graft-v-host disease (GVHD) and T cell depletion of the donor marrow were statistically significant risk factors, and GVHD appeared to play a contributing role, particularly in the setting of human leukocyte antigen (HLA) disparity. Two patients had no identifiable risk factors. Prophylaxis or treatment with acyclovir had no detectable effect in the patients; all but two died with uncontrolled lymphoproliferation. 相似文献
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The evaluation of gastrointestinal function in diabetic patients 总被引:2,自引:0,他引:2
Quigley EM 《World journal of gastroenterology : WJG》1999,5(4):13-282
Nowadays,anumberofoptionsareavailablefortheasesmentofgastricmotorfunction.Thus,aglobalevaluationofgastricmotorfunctionmaybeob... 相似文献
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Incidence and determinants of moderate COPD (GOLD II) in male smokers aged 40–65 years: 5-year follow up 下载免费PDF全文
Roeland MM Geijer Alfred PE Sachs Theo JM Verheij Philippe L Salom Jan-Willem J Lammers Arno W Hoes 《The British journal of general practice》2006,56(530):656-661
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD. 相似文献