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101.
绞股蓝多甙100mg/kg·d-1×4wk灌胃给药,观察结果表明该物具有降低实验性高脂血症家兔的血脂水平及血清过氧化脂质、心肌褐脂质含量的作用。  相似文献   
102.
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.  相似文献   
103.
采用临床流行病学方法对IgG指数和IgG合成率的实用价值进行评价。结果发现:在对多发性硬化(MS)的诊断中,IgG指数的敏感性、特异性和阳性结果似然比分别是60%、65%和1.80,而IgG合成率分别为50%,65%和1.43。在排除皮质类固醇激素的影响后,IgG指数的敏感性和阳性结果似然比分别是84%和2.4,IgG合成率则分别是79%和2.26。此外,IgG指数和IgG合成率对于判断是否存在中枢神经系统器质性损害有较大的意义  相似文献   
104.
 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
105.
Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists.  相似文献   
106.
Objective To analyze the relations between obstructive sleep apnea and bradyarrhythmia.Methods From 1999 to 2005,203 patients who came from Bering Tongren Hospital and Fuwai Hospital were found to have sleep apnea in an ambulatory study. A Hoher electrecardiogram was recorded for 24 hours within 2 weeks after patients were diagnosed as obstructive sleep apnem Results Nocturnal episodes of bradyarrhythmia were identified in 12(5.9%)of 203 patients.Body mass index and respiratory disturbance index in patients with bradyarrhythmia(n=12)were higher than those in patientswithour bradyarrhymia(n=191)(34±5 735.24±6 and 63±15 vs.25±5,respectively,both P<0.01).There was a significant difference in end-apneic oxygen saturation in apnea/hypopnea episodes with and without bradyarrhythmia(63%±15% vs.75%±11%,P<0.05).A linear relation between end-apneic oxygen saturation and number of sinus arrests and heart blocks was not found.Conclusions Patients with apnea-associated bradyarrhythmia have higher body mflgB index and higher respiratory disturbance index than patients without bradyarrhythmi&Bradyarrhythmia occurres independently from decrease in oxygen saturation.  相似文献   
107.
目的:观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法:34只Wistar大鼠,随机分为4组:①平原对照组;②急性缺氧组;③慢性缺氧组;④返回平原组。以放射性生物微球法测定心肌血流量。结果:急性缺氧引起PaO2、心输出量及氧运送量降低,但左、右心室心肌血流量明显增加;慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加,而心肌血流量接近正常。停止缺氧30d后,上述所有指标均与平原以  相似文献   
108.
目的建立重庆市正常牙合青少年牙颌模型牙列指数的正常值,为正畸临床提供依据.方法选取重庆市正常牙合青少年牙颌模型92付(男45付,女47付),测量牙冠宽度、牙弓宽度,计算Bolton指数和Pont指数,对测量结果进行统计分析并与国内外相关资料进行对比研究,对Bolton指数和Pont指数的临床应用价值进行评价.结果Bolton指数和Pont指数存在种族和地区差异,结论Bolton指数和Pont指数在正畸临床中均有一定的应用价值,临床上应参照本民族和地区的标准.  相似文献   
109.
We describe a novel index derived from the auditory evoked potential, the auditory evoked potential index, and we compare it with latencies and amplitudes related to clinical signs of consciousness and unconsciousness. Eleven patients, scheduled for total knee replacement under spinal anaesthesia, completed the study. The initial mean (SD) value of the auditory evoked potential index was 72.5 (11.2). During the first period of unconsciousness it decreased to 39.6 (6.9) and returned to 66.8 (12.5) when patients regained consciousness. Thereafter, similar values were obtained whenever patients lost and regained consciousness. Latencies and amplitudes changed in a similar fashion. From all parameters studied, Na latencies had the greatest overlap between successive awake and asleep states. The auditory evoked potential index and Nb latencies had no overlap. The consistent changes demonstrated suggest that the auditory evoked potential index could be used as a reliable indicator of potential awareness during propofol anaesthesia instead of latencies and amplitudes.  相似文献   
110.
东北地区风寒指数气候特征与冷习服锻炼日期的确定   总被引:2,自引:0,他引:2  
应用中国东北48个站10年的逐日气象资料,分析了风寒指数(Vt)的候、月、旬、日平均值,据此,提出了各地可供冷习服锻炼的天数及可开始锻炼的日期等。研究结果在生物气候区划和指导部队耐寒锻炼等方面有重要作用,也有助于较精确的估算冷应激强度及寒冷环境对作业能力影响的预测。  相似文献   
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