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61.
目的探讨精子冷冻环无保护剂玻璃化冷冻方法的可行性。方法正常精液标本上游处理后,进行常规冷冻和冷冻环无保护剂的玻璃化冷冻,复苏后分别从活力参数及电镜下超微结构等指标比较两种冷冻方法的效果。结果两种方法冷冻后精子存活率、活动率之间差异无显著性(48%∶48%;44.5%∶43.5%,P>0.05),但均较未冷冻的89%和88.5%明显下降(P<0.001)。超微结构亦较未冷冻时发生了一定的改变,但核结构基本保持完整。结论精子冷冻环无保护剂的玻璃化冷冻是一种简单、方便而行之有效的冷冻方法。 相似文献
62.
René Schwendimann Hugo Bühler Sabina De Geest Koen Milisen 《BMC health services research》2006,6(1):69
Background
Patient falls in hospitals are common and may lead to negative outcomes such as injuries, prolonged hospitalization and legal liability. Consequently, various hospital falls prevention programs have been implemented in the last decades. However, most of the programs had no sustained effects on falls reduction over extended periods of time. 相似文献63.
Michiel R. de Boer Jos Twisk Annette C. Moll Hennie J. M. Völker-Dieben Henrica C. W. de Vet Ger H. M. B. van Rens 《Ophthalmic & physiological optics》2006,26(6):535-544
Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo. 相似文献
64.
BMP-2 gene polymorphisms and osteoporosis: the Rotterdam Study. 总被引:7,自引:0,他引:7
Marco Medici Joyce Bj van Meurs Fernando Rivadeneira HongYan Zhao Pascal P Arp Albert Hofman Huibert Ap Pols André G Uitterlinden 《Journal of bone and mineral research》2006,21(6):845-854
After reported associations of variations in the BMP-2 gene with osteoporosis in small populations, we studied the association of the BMP-2 gene polymorphisms Ser37Ala and Arg190Ser with osteoporosis in 6353 men and women from the Rotterdam Study. We did not observe an association of these variants with BMD, bone loss, hip structural analysis parameters, and fracture risk. INTRODUCTION: Bone morphogenetic protein 2 (BMP-2) plays a role in osteoblast differentiation. BMP-2 gene variation has previously been associated with osteoporosis in various small populations, but current evidence remains inconclusive about the exact association with osteoporosis. Therefore, we studied the association of two polymorphisms located in the BMP-2 gene (Ser37Ala and Arg190Ser) and haplotypes defined by these polymorphisms with BMD, rates of bone loss, parameters of hip structural analysis (HSA), and fractures in the Rotterdam Study, a large prospective cohort study of diseases in the elderly. MATERIALS AND METHODS: Databases were searched for polymorphisms and haplotype blocks in the BMP-2 gene region. Allele frequencies for Ser37Ala and Arg190Ser were determined in 60 blacks and 110 Chinese from Coriell panels. Genotype data on Ser37Ala and Arg190Ser were available for 6353 individuals from the Rotterdam Study population. Haplotype alleles defined by Ser37Ala and Arg190Ser were inferred using PHASE software. Genotype and haplotype analyses for BMD (measured at the lumbar spine and femoral neck), bone loss per year (measured at the femoral neck), and HSA were performed using AN(C)OVA. Fractures were analyzed using a Cox proportional-hazards model and logistic regression. All outcomes were adjusted for age, height, and weight. RESULTS: Allele frequencies were 2.5% for Ala37 and 40.2% for Ser190, whereas haplotype allele frequencies were 57.28% (Ser37Arg190), 40.19% (Ser37Ser190), 2.50% (Ala37Arg190), and 0.02% (Ala37Ser190). For BMD, bone loss, HSA outcomes, and (incident) fractures, no differences could be seen between genotype and haplotype groups. Conclusions: In this large population-based cohort of Dutch whites, we conclude that the BMP-2 Ser37Ala and Arg190Ser polymorphisms or haplotypes thereof are not associated with parameters of osteoporosis. 相似文献
65.
MPO和NAT2基因多态性与成人急性白血病易感性 总被引:2,自引:0,他引:2
目的研究髓过氧化物酶(MPO)和N-乙酰基转移酶2(NAT2)基因多态性与成人急性白血病易感性的关系.方法用1∶1配对病例-对照研究方法,收集成人急性白血病患者和对照各139例,应用聚合酶链-内切酶片段(PCR-RFLP)方法分析病例组和对照组MPO和NAT2的基因多态性,比较不同基因型与成人急性白血病易感性.结果 MPO-463A等位基因分布频率病例组低于对照组,MPO(G-463A)各基因型在病例组与对照组中的分布差异有统计学意义(χ^2=7.026,P〈0.05,OR=0.505,95%CI=0.325~0.847).NAT2乙酰化表型频率在病例组与对照组的分布差异无统计学意义(χ^2=2.260,P〉0.05);但NAT2*5 481T等位基因和NAT2*6 590A等位基因分布频率病例组高于对照组(P〈0.05).结论 MPO与成人急性白血病易感性相关,携带MPO(G-463A)突变基因型(GA/AA)个体可降低白血病的发病风险;NAT2乙酰化表型可能与白血病的易感性无关,但NAT2*5(C481T)、NAT2*6(G590A)单核苷酸突变频率病例组明显高于对照组. 相似文献
66.
Is colonic electrical activity a similar phenomena to small-bowel electrical activity? 总被引:4,自引:0,他引:4
Dr. José A. S. Medeiros M.D. Ph.D. Fausto A. Pontes M.D. Ph.D. Octávio A. R. O. Mesquita 《Diseases of the colon and rectum》1997,40(1):93-99
PURPOSE: This study was designed to investigate colonic spike bursts regarding 1) their migration behavior, 2) their pressure correlates, and 3) comparing colonic short spike bursts with spike bursts from migrating myoelectric complex from the small bowel. METHODS: Rectosigmoid electromyography and manometry were recorded simultaneously in seven normal volunteers and electromyography alone in five others during two hours of fasting and for two hours after one 2,100-kJ meal. One patient with an ileostomy was also studied by the same method to record the migrating myoelectric complex from the terminal ileum during fasting. RESULTS: Three kinds of spike bursts were observed in the pelvic colon: rhythmic short spike bursts, migrating long spike bursts, and nonmigrating long spike bursts. The meal significantly increased the number of migrating and nonmigrating long spike bursts (from 25 to 38.7 percent of the recording time;
P
<0.01). These bursts of potentials showed a peak 15 minutes after the meal, which may be caused by the gastrocolic reflex. Migrating long spike bursts started anywhere along the rectosigmoid and migrated from there aborad 82 percent of the time and orad or in both directions in 10 or 7 percent of the time, respectively. They originated pressure waves 99 percent of the time. Short spike bursts were more frequent before the meal (15.1 percent before and 9.6 percent after the meal), but the difference was not significant; they neither propagated nor initiated pressure waves detected by the miniballoon. CONCLUSIONS: Migrating long spike bursts were the only potentials that migrated, sometimes for short distances. Short spike bursts are a different phenomenon from the small-bowel migrating myoelectric complex because they do not migrate; they can occur during the postprandial period and never originated intraluminal pressure waves.Supported by a grant from the Instituto Nacional de Investigação Científica, Proc. DBI-22086.Presented at the meeting of the Portuguese Congress of Gastrenterology, Vila Moura, Portugal, June 2 to 5, 1993. 相似文献
67.
目的:探讨EB病毒(EBV)感染与非鼻咽部T细胞淋巴瘤的关系。方法:用单克隆抗体UCHL-1、L26及EB病毒编码的潜在膜蛋白-1(LMP-1),免疫组化染色确定肿瘤的免疫表型及EB病毒转化蛋白的表达。采用原位杂交方法检测EBV编码的EBERs。结果:21例非鼻咽部T细胞淋巴瘤EBERs5例阳性的(23.8%),其中给内淋巴瘤3例,肺和胃肠淋巴瘤各1例。阳性细胞约占肿瘤细胞的10%~70%。5例EBERs阳性病例中仅1例表达LMP-1,为结内淋巴瘤。结论:非鼻咽部T细胞淋巴瘤可能与EBV的感染有关,LMP-1的阳性率较EBERs低。 相似文献
68.
Jean-Pierre Bassand René Faivre Pascal Berthout Jean-Claude Cardot Josette Verdenet Roland Bidet Jean-Pierre Maurat 《European journal of nuclear medicine and molecular imaging》1987,13(8):419-424
The influence of left ventricular volume variations and regurgitant fraction variations upon left ventricular ejection fraction, during exercise was examined using equilibrium radionuclide angiography in patients suffering from aortic regurgitation. Ejection fraction (EF), regurgitant fraction (RF), end diastolic volume (EDV) and end systolic volume (ESV) variations from rest to peak exercise were determined in 44 patients suffering from chronic aortic regurgitation (AR) and in 8 healthy volunteers (C). In C, EF increased (+0.10±0.03, P<0.01) and ESV decreased significantly (-23%±12%, P<0.01) RF and EDV did not vary significantly. In AR patients, EF, EDV and ESV did not vary significantly because of important scattering of individual values. Changes in EF and ESV were inversely correlated (r=-0.79, P<0.01) and RF decreased significantly (-0.12±0.10, P<0.01). Volumes and EF changes during exercise occurred in three different ways. In a 1st subgroup of 7 patients, EF increased (+0.09±0.03, P<0.05) in conjunction with a reduction of ESV (-24%±12%, P<0.05) without a significant change in EDV. In a 2nd group of 22 patients. EF decreased (-0.04±0.07, P<0.01) in association with an increase in ESV (+17%±16%, P<0.01) and no change in EDV. In a 3rd subgroup of 15 patients, EF decreased (-0.02±0.06, P<0.01) despite a reduction in ESV (-7%±6%, P<0.01) because of a dramatic EDV decrease (-10%±6%, P<0.05). In this subgroup, changes in EF were inversely correlated with changes in ESV (r=-0.55, P<0.01) and positively related to EDV variations (r=0.42, P=0.02). EDV related to EDV variations (r=0.42, P=0.02). EDV changes were weakly, but significantly, correlated to RF decrease (r=0.39, P<0.05). We conclude that changes in left ventricular ejection fraction during exercise in patients with chronic aortic regurgitation are significantly related in some patients to changes in ventricular loading conditions as well as contractile state. Therefore, a correct interpretation of EF changes during exercise requires the simultaneous determination of changes in LV volumes.Abbreviations EDV
end diastolic volume
- EF
ejection fraction
- ESV
end systolic volume
- LV
left ventricle
- RV
right ventricle 相似文献
69.
70.
【目的】了解手术创伤对术后全身炎症反应综合征 (SIRS)的影响。【方法】搜集外科重症监护室 (SICU) 335例患者的术后资料 ,分析不同手术组SIRS发病率 ;手术时间、失血量与SIRS持续时间的关系 ;SIRS持续时间与术后并发症的关系。【结果】术后SIRS发病率为 75 8% ,大手术高达 92 4 % ;无并发症患者失血量与SIRS持续时间呈正相关 (r1=0 783,P<0 0 1) ,手术时间与SIRS持续时间呈正相关 (r2 =0 398,P <0 0 1) ;随着SIRS持续时间延长 ,并发症发病率显著增高 (P<0 0 5 )。【结论】术后SIRS发生、发展与手术创伤密切相关 ;监测SIRS进程有助于及早发现并发症 相似文献