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排序方式: 共有4846条查询结果,搜索用时 15 毫秒
21.
健康成人135例心率变异性时域分析 总被引:2,自引:0,他引:2
目的:探讨国人心率变异时域分析各项指标的正常值。方法:应用清华-西安兰港监测系统对135例18~79岁健康成人连续24h动态心电图监测。结果:①心率变异性时域:SDNN、SDSD、SDANN、RMSSD、PNN50分别为129.52±27.25ms;21.18±8.20ms;114.78±26.84ms;31.36±12.67ms;8.50 ± 7.80ms,所测得正常值范围与国内外研究结果相似。②18~35岁组、36~59岁组,均与≥60岁组有非常显著的差异(P<0.01,或P<0.05)。③各年龄组男女间SDNN、SDSD、PNN50无显著差异(P>0.05),但SDANN男性较女性大(P<0.05);女性RMSSD较男性大(P<0.05)。结论:SDNN>100ms;SDSD>12ms;SDANN>87ms;RMSSD>18ms;PNN50>0.7%可作为HRV时域分析参考正常值。 相似文献
22.
Mario Casmiro MD 《Neurosurgical review》1998,21(1):43-47
A 70-year-old female presented with the clinical triad of normal pressure hydrocephalus (NPH) and senile tremor. Neuroimaging disclosed findings of both NPH and empty sella (ES). A ventriculoperitoneal shunt did not modify the clinical course except for a mild and transient improvement, and shunt malfunction occured later on. The association of NPH and ES may result from a common underlying mechanism such as transient increases in intracranial pressure. 相似文献
23.
年龄因素对健康人心率变异性的影响 总被引:1,自引:0,他引:1
目的探讨年龄因素对健康人心率变异性(HRV)的影响。材料与方法将236例健康人分为五个年龄组,使用美国先进医用设备公司5.0版本HRV软件做短时时域及频域HRV分析。结果年龄因素对健康人HRV短时时域和频域分析的多项指标产生显著影响,随着年龄增大,时域指标中的HRSD、SDANN、rMSSD及PNN50均逐渐降低;随着年龄增长,频域指标中各频段下的绝对面积,即:VLF、LF、MF及HF均逐渐降低;而频域指标中各频段下的相对面积,即:VLFP、LFP、MFP、HFP随着年龄增长呈不同的发展趋势。LF/HF随着年龄的增加而逐渐升高。结论HRV随着年龄的增加而下降,尤以迷走神经活性下降为显著。频域指标中各频段的相对面积较绝对面积能更敏感地反映交感、迷走神经张力的消长。 相似文献
24.
25.
目的 检验幼师女生自尊水平与心理健康的关系。方法 使用自尊量表和SCL-90量表对196名幼师女生进行测量。结果 幼师女生的心理健康总体水平不高,幼师女生自尊水平与心理健康之间存在的显著的负相关。结论 一方面幼师女生的自尊受心理健康水平的影响,特别是抑郁、强迫和人际敏感等方面;另一方面幼师女生的自尊也会影响她们的心理健康水平。 相似文献
26.
Yewande E. Odeyemi ODene Lewis Julius Ngwa Kristen Dodd Richard F. Gillum Alem Mehari 《Journal of the National Medical Association》2019,111(1):94-100
Purpose
There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.Methods
In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.Results
There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.Conclusions
The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction. 相似文献27.
正视眼角膜表面形态和屈光力分析 总被引:2,自引:0,他引:2
目的:为探讨正视眼角膜表面形态和屈光力。方法:83只正视眼用TomeyTMS-2TM型角膜地形图检查角膜表面形态和屈光力。结果:①绝对等级全角膜有2~5种颜色,屈光力有轻微的变化;②角膜中央屈光力为43.854±1.321D,Simk值为44.142±1.342D,平均屈光力(ACP)为43.007±1.473D,角膜表面规则系数(SRI)为0.241±0.213,角膜表面不对称系数(SAI)为0.321±0.130,不规则散光指数(IAI)为0.357±0.006。结论:本文检查的国人正视眼角膜表面形态和屈光力数值,可为屈光性角膜手术提供解剖依据。 相似文献
28.
The thymus as primary site for antigen-specific T suppressor cells in neonatally induced tolerance to bovine serum albumin 总被引:1,自引:0,他引:1
The ontogeny of antigen-specific T suppressor cells in thymus and spleen was analyzed in CBA/Ca mice which were rendered tolerant as neonates by subimmunogenic doses of bovine serum albumin (low-zone tolerance). Activity of T suppressor cells from those mice was assessed by an assay in which spleen cells from animals primed with fluorescein-conjugated human gamma globulin can be stimulated in vitro to produce IgG anti-fluorescein antibodies when cultured in the presence of fluorescein-conjugated bovine serum albumin. Carrier-specific T suppressor cells appear first in the thymus (day 10), and much later (day 30) in the spleen. The data are discussed in connection with the possible role of T suppressor cells during induction of tolerance in newborn mice. 相似文献
29.
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
30.
Lugli A Forster Y Haas P Nocito A Bucher C Bissig H Mirlacher M Storz M Mihatsch MJ Sauter G 《Human pathology》2003,34(10):994-1000
Calretinin is a calcium-binding protein expressed in different normal and neoplastic tissues. Early studies suggested that calretinin is a useful marker to differentiate adenocarcinomas from malignant mesotheliomas of the lung, but subsequent work has shown that calretinin can be expressed in several other tumor types. To systematically investigate the epidemiology of calretinin expression in normal and neoplastic tissues, we used tissue microarrays (TMAs) to analyze the immunohistochemically detectable expression of calretinin in 5233 tissue samples from 128 different tumor categories and 76 different normal tissue types. At least 1 case with weak expression could be found in 74 of 128 (58%) different tumor types and 46 entities (36%) had at least 1 tumor with strong positivity. In normal tissues, a particularly strong expression was found in Leydig cells of the testis, neurons of the brain, theca-lutein and theca interna cells of the ovary, and mesothelium. In tumors, strong calretinin expression was most frequently found in malignant mesotheliomas (6 of 7), Leydig cell tumors of the testis (5 of 5), adenomas of adrenal gland (5 of 9), and adenomatoid tumors (4 of 9). In summary, calretinin is frequently expressed in many different tumor types. Metastases of various different origins must be included in the differential diagnosis of calretinin-positive pleura tumors. 相似文献