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101.
目的:探讨宫颈癌的临床、病理特点、诊治方法及预后因素。方法:收集1996年1月至2001年1月226例宫颈癌患者进行回顾性分析。结果:平均患病年龄为48.18岁。130例患者为阴道流血,70例为阴道流液,25例下腹疼痛,l例精神减退、贫血、浮肿。病理分期:Ⅰ期病例数为169例(75%);Ⅱ期病例数为3l例(13.72%);Ⅲ期病例数为23例(10.18%);Ⅳ期病例数为3例(1.1%)。比较2l例宫颈鳞癌与宫颈腺癌的转移,显示后者的腹主动脉旁淋巴结转移、肾上腺转移、子宫转移、胸水形成明显高于前者。结论:重视宫颈癌发病相关因素及临床症状,争取早期诊断,严格手术病理分期,选择适当治疗方案。 相似文献
102.
血清乙型肝炎病毒标志物不同表现模式及肝功能异常对肾移植受者存活率的影响 总被引:1,自引:0,他引:1
目的 探讨血清乙型肝炎病毒标志物不同表现模式对肾移植受者长期存活的影响。方法 对 62例血清乙型肝炎病毒标志物阳性者及 1 96例血清乙型肝炎病毒标志物全阴性者肾移植术后的肝功能、人肾均存活的存活率等指标进行随访和回顾性分析。结果 术后早期血清乙型肝炎病毒标志物阳性组与血清乙型肝炎病毒标志物阴性组比较 ,肝功能异常发生率的差异无显著性 (P >0 .0 5) ;术后中远期 ,HBsAg、HBeAg及抗 HBc阳性者的肝功能受损率明显高于血清乙型肝炎病毒标志物阴性组及HBsAg、抗 HBe、抗 HBc阳性者 (P <0 .0 5) ,其人肾均存活的存活率也最低 (P <0 .0 5)。结论 对HBsAg、抗 HBe及抗 HBc阳性者进行肾移植应慎重 ,而HBsAg、HBeAg及抗 HBc阳性者则不适宜接受肾移植 相似文献
103.
6186例脑卒中患者发病时间的季节性分析 总被引:3,自引:0,他引:3
目的探讨青岛市区脑出血(CH)、脑梗死(CI)、蛛网膜下腔出血(SAH)发病时间的季节规律。方法收集青岛市1998年~2002年脑卒中患者6186例,其中CH1179人,CI4821人,SAH186人。圆分布分析探讨脑卒中患者发病时间的季节规律。结果CH冬季高发,平均角在1月份(P<0.05),男性患者的平均角在2月份(P<0.05),女性患者的平均角在1月份(P<0.05);CI秋季高发,男、女间无差别,平均角在10月份(P<0.05);SAH秋季高发,平均角在10月份(P<0.05),男性患者的平均角在9月份(P<0.05),女性患者的平均角在10月份(P<0.05)。结论青岛市的脑卒中发病具有季节性,在脑卒中预防工作中要充分考虑其发病的季节特点,并采取相应的措施。 相似文献
104.
E Baracca C Longhini S Aggio C Brunazzi A E Aubert R Pansini 《European heart journal》1991,12(2):249-261
The present study applies a non-invasive method to the quantitative evaluation of left ventricular stiffness in normal subjects and in patients with ischaemic heart disease (IHD). We have studied 20 patients with IHD and 25 healthy subjects. The third heart sound (S3) was detectable in all patients. We have correlated the energy spectrum of S3, divided into 15 Hz bands, with a series of echocardiographic parameters. The existence of a significant correlation between the spectrum energy and the diameter and thickness of the left ventricle at the moment of S3 allowed us to explore the possibility of interpreting the origin of S3 based on a mathematical model. Our hypothesis has been that, once the left ventricle starts vibrating, it behaves as a simple physical model composed of a mass and an elastic element. To this purely elastic model one can add a factor accounting for viscosity, with a damping effect, to obtain a more complex viscoelastic model. The stiffness coefficient 'k' was computed in both models from the peak frequency of S3 and the left ventricular mass at the moment of S3. Furthermore, in the viscoelastic model, the damping element 'c' was also computed. Both parameters--k and c--were significantly increased in the group with IHD compared with the control group. Although a simplification of the vibrating system, these models make it possible to obtain non-invasively information on the characteristics of the left ventricle through the combined use of echocardiography and spectral analysis of S3. 相似文献
105.
106.
Fifty-five students and staff at Robert Gordon's Institute of Technology completed a food frequency questionnaire and then weighed their food for one week. Several methods of calculating nutrient intakes from the questionnaire are compared to results from the weighed inventory. Intakes of energy and several nutrients calculated using estimated typical portion weights were less than those derived from the weighed inventory. Food groups contributing to the apparent under-estimation have been identified. A further method of calculation involved derivation of a factor for each food group such that the frequency estimated from the questionnaire multiplied by the factor equalled the average weight of the foods in that group that had been eaten. Using these factors instead of the typical portion weights resulted in closer agreement to the weighed inventory method, but the difference ranged from positive for some groups to negative for others. Use of separate factors for each group of subjects reduced the range of differences to the weighed inventory method. 相似文献
107.
The receiver operating characteristic (ROC) method is a useful and popular tool for testing the efficiency of various diagnostic tests applicable to functional MRI (fMRI) data. Typically, the diagnostic tests are applied on simulated and pseudo-human fMRI data, and the area under the ROC curve is used as a measure of the efficiency of the diagnostic test. The effectiveness of such a method depends on how well the simulated data approximate the real data. For multivariate statistical methods, however, this technique is usually inadequate, as the spatial dependence among voxels is ignored for simulated data. In this work a modified ROC method using real fMRI data with a broader scope is proposed. This method can be applied to most fMRI postprocessing techniques, including multivariate analyses such as canonical correlation analysis (CCA). Also, the relationship of the modified ROC method with the conventional ROC method is discussed in detail. 相似文献
108.
Tomotaka Sobue Takaichiro Suzuki Tsuguo Naruke The Japanese Lung Cancer Screening Research Group 《Cancer science》1992,83(5):424-430
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population. 相似文献
109.
Albert Kingman 《Journal of periodontal research》1992,27(4):378-389
Simulation studies were conducted to address specific statistical issues which arise in the design and analysis of gingivitis studies whose principal aim is the demonstration of superiority or equivalence of one product to another. The effects of measurement scale, using differences or ratios of group means, particular statistical test produces and specific rules demonstrating superiority or equivalence were investigated. An alternative concept to equivalence—denoted “least as good”—was also defined and evaluated. For a wide class of possible distributions of gingivitis scores, characterized by specific gamma distributions, the student-t test applied to means of subject GI gingivitis scores proved to be the most powerful of the test produces considered, having statistical properties quite similar to the randomization or permutation test procedure. Transformations of subject GI mean gingivitis scores did not produce an advantage in demonstrating either superiority or equivalence, and in some cases made it more difficult. Little difference was observed in test results when using the difference in group means as compared with using the ratio of group means for demonstrating either equivalence or superiority. The clinically significant rule produced the lowest false-positive rates for products slightly better than the active control, and similar false-positive and -negative rates as the statistically significant rule for products clearly superior to the active control. Demonstration of product equivalence will require more subjects per group than demonstrating product superiority, the size of this difference being a function of the definition of superiority that is accepted. Showing that the 90% confidence interval for 100*R is completely contained within the [90%, 110%] interval is the preferred method of demonstrating equivalence today, although much more research needs to be done to improve methods for demonstrating product equivalence. The “least as good” alternative to “equivalence” makes it easier to demonstrate “equivalence” for products slightly better than the active control product, but both experience great difficulty in demonstrating equivalence for lest products not quite as good as the active control. 相似文献
110.
We investigated the regulation of the rat neuron-specific enolase gene using a transient transfection approach. Recent transgenic
mouse studies have shown that a 1.8-kb segment of the ratNSE gene 5′ flanking region, including the first (noncoding) exon but not the first intron, is able to drive expression of a
reporter gene in parallel with endogenousNSE. These data suggest thatcis-acting elements responsible for the spatial and temporal pattern ofNSE gene expression are located within the proximal 1.8 kb of the 5′ flanking sequence. To further investigate this region, we
joined the 1.8-kb regulatory cassette to thecat reporter gene and generated a number of constructs in which the flanking sequence was progressively deleted from the 5′ end.
These constructs were tested by transient transfection into neuronal and nonneuronal cells, followed by an assay for CAT activity.
We found that as little as 255 bp of 5′ flanking sequence was able to confer cell type-specificity on the reporter gene. Further
truncation to 120 bp of 5′ sequence resulted in a sharp downregulation of reporter activity in PC12 cells but a significant
rise in both Neuro-2A neuroblastoma cells and nonneuronal Ltk- cells, indicating thatcis-acting elements controlling the regulation ofNSE in Ltk-, Neuro-2A, and PC12 cells may lie within the 135 bp region covered by this deletion. This region contains an AP-2
site and an element similar in sequence and position to a motif identified in the proximal promoter region of the neuron-specific
peripherin gene. Reduction to 95 bp of 5′ sequence resulted in a slight downregulation of CAT activity in all cell lines tested,
and further truncation to 65 bp of 5′ sequence caused a universal reduction to background levels of CAT activity, concomitant
with the disruption of the basalNSE promoter. Our results show that the 5′ flanking region of theNSE gene is capable of conferring cell type-specificity on a heterologous gene in transfected cells and that elements responsible
for this are located within the proximal 255 bp. 相似文献