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排序方式: 共有3048条查询结果,搜索用时 31 毫秒
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The aim of the study was to conduct a structured review of theliterature published on the use of normal sperm morphology,as an indicator of male fertility potential in the in-vitrofertilization (IVF) situation, and to establish the universalpredictive value of this semen parameter. Published literaturein which normal sperm morphology was used to predict fertilizationand pregnancy, during the period 1978-1996, was reviewed. Atotal of 216 articles were identified by the sourcing methodology,but only 49 provided data that could be tabulated and analysed.Of these, only 18 provided sufficient data for statistical analysis.Fifteen studies used the strict criteria to evaluate sperm morphology,two used World Health Organization (WHO) guidelines and oneused both the strict criteria and the WHO guidelines. All thestudies (n=10) using the 5 and 14% normal sperm morphology thresholds(strict criteria) produced positive predictive values for IVFsuccess. In the prediction of pregnancy, 82% (9/11) and 75%(6/8) of the studies produced positive predictive values whenusing the 5% and 14% thresholds respectively. Aggregating thedata produced around the 5% normal sperm morphology threshold(strict criteria), the overall fertilization rates were 59.3%(1979/3337; per oocyte) for the 4% group and 77.6% (10345/13327;per oocyte) for the >4% group, and the overall pregnancyrates were 15.2% (60/395; per cycle) and 26.0% (355/1368; percycle) respectively. The no-transfer rates across the 5% thresholdwere 24.0% (86/359; per cycle) in the 4% group compared to 7.4%(80/1088; per cycle) in the >4% group. The inclusion of anaccurately evaluated normal sperm morphology count as an integralpart of the standard semen analysis makes this analysis stillthe most cost-effective means of evaluating the male factor. 相似文献
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Roberts AD Clark SA Townsend NE Anderson ME Gore CJ Hahn AG 《European journal of applied physiology》2003,88(4-5):390-395
Nineteen well-trained cyclists (14 males and 5 females, mean initial V˙O2max 62.3 ml kg–1 min–1) completed a multistage cycle ergometer test to determine maximal mean power output in 4 min (MMPO4min), maximal oxygen uptake (V˙O2max) and maximal accumulated oxygen deficit (MAOD). The athletes were divided into three groups, each of which completed 5, 10
or 15 days of both a control condition (C) and live high:train low altitude exposure (LHTL). The C groups lived and trained
at the ambient altitude of 610 m. The LHTL groups spent 8–10 h night–1 in normobaric hypoxia at a simulated altitude of 2,650 m, and trained at the ambient altitude of 610 m. The changes to MMPO4min, V˙O2max and MAOD in response to LHTL altitude exposure were not significantly different for the 5-, 10- and 15-day treatment periods.
For the pooled data from all three treatment periods, there were significant increases in MMPO4min [mean (SD) 5.15 (0.83) W kg–1 vs 5.34 (0.78) W kg–1] and MAOD [50.1 (14.2) ml kg–1 vs 54.9 (13.1) ml kg–1] in the LHTL athletes between pre- and post-altitude exposure. There were no significant changes in MMPO4min [5.09 (0.76) W kg–1 vs 5.16 (0.86) W kg–1] or MAOD [50.5 (14.1) ml kg–1 vs 49.1 (13.0) ml kg–1] in the C athletes over the corresponding period. There were significant increases in V˙O2max in the athletes during both the LHTL [63.2 (9.0) ml kg–1 min–1 vs 64.1 (9.0) ml kg–1 min–1] and C [62.0 (8.6) ml kg–1 min–1 vs 63.4 (9.2) ml kg–1 min–1] conditions. In these athletes, there was no difference in the impact of 5, 10 or 15 days of LHTL on the increases observed
in MMPO4min, V˙O2max or MAOD; and LHTL increased MMPO4min and MAOD more than training at low altitude alone.
Electronic Publication 相似文献
34.
A model for susceptibility artefacts from respiration in functional echo-planar magnetic resonance imaging 总被引:1,自引:0,他引:1
Respiration causes variations in the signals acquired during magnetic resonance imaging (MRI) and therefore is a significant source of noise in functional brain imaging. A primary component of respiratory noise may arise from variations of bulk susceptibility or air volume in the chest. Here we investigate the nature of the image artefacts that can be caused by such changes. We develop a simple model which attempts to mimic the effects of variations in susceptibility and volume during respiration. Theoretical calculations, computer simulations and imaging experiments with this model show that small variations in susceptibility within the thorax from alterations in the paramagnetism of cavity gas may lead to a shift of the image on the order of 0.1 pixels as well as a shading of the intensity by +/-1%. These effects are observed to be predominant in the phase-encoding direction. They may lead to the production of spurious activations in functional MRI and are likely to be of more importance at higher field strengths. 相似文献
35.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
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Mark Ehlers Marc Bjurlin John Gore Raj Pruthi Gopal Narang Ray Tan Matthew Nielsen Anqi Zhu Allison Deal Angela Smith 《Urologic oncology》2021,39(1):76.e1-76.e7
ObjectiveFinancial toxicity (FT) has been defined as the patient-level impact of the costs of cancer care. Our objective was to better characterize FT among bladder cancer patients as well as oncologic, demographic and insurance characteristics related to FT.MethodsWe conducted a cross-sectional survey of the Bladder Cancer Advocacy Network Patient Survey Network using the validated COST (COmprehensive Score for financial Toxicity) questionnaire. Our primary outcome was relative degree of FT, with lower COST scores corresponding to worse FT. Wilcoxon rank sum tests and multiple regression were used to evaluate differences in demographic, diagnostic and treatment characteristics as they related to degree of FT.ResultsAmong 226 patients, median age was 68 years with 64% male, 83% married, and 49% with Medicare with supplemental insurance. Respondents reported an average of 65 months since diagnosis, with 62% reporting noninvasive disease. Mean COST was 28.4 (range 0–44). On multivariable analysis, patients who were younger, with a household annual income less than $50,000, not retired, or with insurance that was neither Medicare nor employer paid were significantly more likely to have worse FT. A majority of respondents (63.5%) agreed or strongly agreed that they would be interested in discussing cost in the context of their treatment preferences, independent of COST score (P = 0.24).ConclusionsA national cross-sectional survey demonstrated high prevalence of FT which was worse among younger patients with lower incomes, not retired, and without employer-paid or Medicare insurance. Most patients preferred to discuss treatment costs with their bladder cancer provider. 相似文献
40.
Katagiri Daisuke Wang Feng Gore John C. Harris Raymond C. Takahashi Takamune 《Clinical and experimental nephrology》2021,25(7):685-699
Clinical and Experimental Nephrology - Complex molecular cell dynamics in acute kidney injury and its heterogeneous etiologies in patient populations in clinical settings have revealed the... 相似文献