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91.
目的探讨三种手术方式对腰椎间盘突出症(LDH)临床疗效的影响。方法 2007年1月~2012年10月于我科行手术治疗LDH的患者中选择110例患者,男63例,女47例;年龄18~73岁,平均45岁;均为单节段椎间盘突出(L3/46例,L4/560例,L5/S144例)。分别采用腰椎间盘髓核摘除术(A组,40例)、椎间融合联合单侧椎弓根螺钉内固定(B组,51例)、腰椎间盘髓核摘除联合棘突间稳定装置X-STOP系统植入(C组,19例),3组患者一般资料比较差异均无统计学意义(0.05)。每位患者术前及术后末次随访时通过完成欧洲五维健康量表及进行Oswestry功能障碍指数评分,比较评分改善情况。结果 110例患者均获得随访,平均随访时间18个月(6~38个月),末次随访时EQ-VAS评分、EQ-5D健康指数和ODI评分组内比较均明显改善(0.05),组间比较均无统计学差异(0.05)。结论对于单纯LDH可行腰椎间盘髓核摘除术,LDH合并腰椎不稳者可行椎间融合+单侧椎弓根螺钉内固定,对于椎间盘突出合并椎管狭窄,尤其是临床症状在屈曲位缓解的患者尤其适宜椎间盘髓核摘除联合棘突间动态内固定。  相似文献   
92.
The Scandinavian Simvastatin Survival Study (4S) was a double-blind. randomized placebo-controlled multi-centre clinical trial of long-term Simvastatin therapy in patients with coronary heart disease who had total cholesterol levels between 5.5 and 8.0 mmol/1, comprising 4444 patients, equally distributed to a Simvastatin and a placebo group. Patients achieved a significant 30% relative reduction in overall mortality with Simvastatin therapy through a 42% relative reduction in coronary heart disease mortality. Lp(a) lipoprotein levels in Scandinavian coronary heart disease patients were strikingly higher than in healthy controls. Numbers of deaths in the Simvastatin group differed significantly between quartiles of Lp(a) lipoprotein levels, the reduction in deaths being most pronounced in the second (next to lowest) quartile. Subjects with major coronary events had significantly higher Lp(a) lipoprotein levels than subjects without such events, in all groups. The relationship between Lp(a) lipoprotein level and total mortality as well as between Lp(a) lipoprotein level and major coronary events was significantly different from zero, in logistic regression analyses. The findings show that Lp(a) lipoprotein predicts major coronary events as well as death in secondary prevention with Simvastatin. This prospective study provides independent confirmation that a high Lp(a) lipoprotein level is a significant coronary heart disease risk factor.  相似文献   
93.
基因功能预测问题中的样本不平衡处理   总被引:3,自引:1,他引:3  
应用机器学习进行分类是基因功能预测的一种重要手段。但是许多预测集中的阳性样本过少,会降低功能预测的效果。针对此问题,本研究对结合支持向量机(SVM)算法的几种常用非平衡数据分类方法进行实验比较,包括投票整合分类器和移动分类面等。在此基础上提出通过加权修正投票的整合策略,以提高预测效果。实验结果显示,结合多数类样本限数取样及整合思想的投票整合法预测效果优于移动分类面法,而在投票整合法基础上的加权修正整合方法在所有方法中获得更好更稳定的结果。  相似文献   
94.
Although testicular biopsy for sperm extraction is a procedure with a potential for complications, sperm retrieval is successful in 30-70% of patients with non-obstructive azoospermia. In order to predict the probability of retrieving at least one testicular spermatozoon we conducted a prospective study of a set of variables in 40 patients with non-obstructive azoospermia. Using the receiver operating characteristic curves, we determined the probability estimates of testicular volume, plasma follicle stimulating hormone (FSH) concentration, Johnsen score and visualization of testicular spermatids in discriminating between patients with successful and failed testicular sperm extraction. Visualization of testicular spermatids provided the best estimate of success of testicular sperm extraction. Of the factors studied using logistic-regression analysis (age, maternal and paternal age at birth, body mass index, luteinizing hormone, testosterone, FSH, testicular volume, the presence of testicular spermatids and Johnsen score), only the presence of spermatids and Johnsen score were independent variables able to predict the success of testicular sperm extraction. The visualization of the presence of spermatids gave a correct prediction of 77% and Johnsen score of 71%. The diagnostic model derived from these independent predictors when validated in 40 patients using the Jackknife technique gave a correct overall prediction of 87%. The probability of successful testicular sperm extraction in patients with non-obstructive azoospermia could be objectively predicted on the basis of simple histopathological criteria represented by the visualization of testicular spermatids and Johnsen score.  相似文献   
95.
Total ovarian volumes were measured before the administrationof HCG in 42 women undergoing treatment for infertility by in-vitrofertilization (IVF) and embryo transfer and considered to havean exaggerated response to stimulation (>20 follicles). Sevenwomen who subsequently developed moderate or severe ovarianhyperstimulation syndrome (OHSS) (n = 7; group 1) were comparedwith 35 matched controls (five matched controls per case; n= 35; group 2) of similar age, number of follicles and durationof infertility who underwent follicular stimulation, oocyterecovery, in-vitro fertilization and embryo transfer duringthe same period but did not develop moderate or severe OHSS.The mean age, duration of infertility and total number of follicleswere similar but the mean total ovarian volume was significantlyhigher in the group of women who developed moderate or severeOHSS compared with controls (271.00 ± 87.00 versus 157.30± 54.20 ml; P < 0.01). We conclude that total ovarianvolume measured before HCG administration is higher in womenwho develop moderate or severe OHSS compared with controls andmay therefore be used as an additional parameter in the preventativestrategy for the ovarian hyperstimulation syndrome.  相似文献   
96.
The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves.  相似文献   
97.
目的:利用神经网络集成(NNE)预测MHC-Ⅰ类分子结合肽。 方法: 基于HLA-A*0201编码的MHC-Ⅰ类分子结合肽数据库(含有628个9聚物)及其结合能力分类,利用NNE分别对具有无、低、中和高4类亲合性的结合肽进行分类预测;同时还进一步利用T细胞真实表位集(含50个表位)评估了NNE的预测性能。 结果: 集成数为12的NNE对上述分类的平均预测命中率可达0.8,而且NNE对潜在T细胞表位的预测能力也较高,约84%的真实表位归于高和中等亲合性的潜在抗原肽一类。 结论: 可以利用神经网络集成预测MHC-Ⅰ类分子结合肽,并进而预测相应的T细胞表位。经适当修改,NNE预测工具可扩展为能涵盖任意长度的Ⅰ类分子结合肽甚至可扩展到Ⅱ类分子结合肽的预测。  相似文献   
98.
Cord blood IgE. III. Prediction of IgE high-response and allergy   总被引:1,自引:1,他引:1  
Screening of total IgE in 2814 cord blood samples was analysed by Phadebas IgE PRIST in 2 1-year birth cohorts (1983–1984 and 1985–1986) in Denmark (n= 1189 + 1625). For follow-up we chose all infants with cord blood IgE≥0.5 kU/1 and a randomly chosen group of the same size with cord blood IgE < 0.5 kU/1. A total group of 762 infants were clinically evaluated at 18 months of age, and in 688 of these we evaluated total and specific IgE. A diagnosis of definite atopy, probable atopy or no atopy was established. In the present study we defined allergic disease as atopic disease combined with elevated total IgE. We found a statistically significant correlation between cord blood IgE and IgE at 18 months of age. Significantly more infants with elevated cord blood IgE had developed allergic disease at 18 months. A cut-off value of 0.3 kU/1 for cord blood IgE was superior to the originally suggested 0.5 kU/1. Significantly more infants with elevated cord blood IgE had developed specific IgE antibodies at 18 months. The most frequent specific IgE antibody was towards cow's milk. Specific IgE antibodies were very rarely found when total IgE was not elevated. A total IgE at the age of 18 months > 26 kU/1 could be regarded as elevated. With regard to allergic disease the positive predictive values of cord blood lgE≥0.3 kU/1 in the 2 series were 21 % and the corresponding sensitivities 67% and 46%, respectively. The risk of developing allergic disease was elevated with a factor 3 to 4 when cord blood IgE ≥ 0.3 kU/1. In a high-risk group based on atopic predisposition and elevated eord blood IgE ≥0.5 kU/1 the relative risk of allergic disease was 5, the predictive value of positive test 38%, the sensitivity 24% and the specificity 96%. Clinical aspects Cord blood IgE was a good predictor of allergic disease at the age of 18 months. A cord blood cut-off IgE value of 0.3 kU/l was superior to other cord blood IgE values with the Phadebas IgE PRIST method.  相似文献   
99.
In a previous study the concept "patient involvement" was found to be strongly predictive of therapy outcome. On the basis of a questionnaire concerning patients' background and motivation, 82 patients were interviewed before treatment. To cover the concept "patient involvement" 16 variables were considered as relevant measures. In a factor analysis four factors accounted for 90% of the common variance. The factors were interpreted in terms of: initial attitudes, attendance, self-confidence and teeth-mindedness.  相似文献   
100.
目的 调查温州市人民医院2018—2021年妊娠期高血压疾病(hypertensive disorders of pregnancy,HDP)患者妊娠结局,并分析其妊娠结局的相关影响因素,为临床采取对应干预措施、降低不良妊娠结局发生风险提供参考。 方法 选取2018年1月—2021年12月于温州市人民医院分娩的400例HDP患者(单胎妊娠)的临床资料,开展回顾性分析,根据其妊娠结局分为不良妊娠结局组(n=157)与正常妊娠结局组(n=243)。比较两组临床资料,分析HDP患者不良妊娠结局发生的影响因素,构建logistic回归模型方程,并分析logistic回归模型的预测价值。 结果 400例HDP患者中共157例(39.25%)发生不良妊娠结局;单因素分析显示患者年龄、孕前BMI、分娩方式、妊娠期糖尿病(gestational diabetes mellitus,GDM)、负性情绪与不良妊娠结局的发生有关(P<0.05);logistic回归模型显示,年龄≥35岁(OR=23.815,95%CI:10.370~54.655)、孕前BMI≥24.0(OR=16.010,95%CI:6.832~34.620)、阴道分娩(OR=16.336,95%CI:7.325~36.403)、GDM(OR=26.337,95%CI:11.908~58.253)、负性情绪(OR=20.682,95%CI:2.791~54.876)均为HDP患者不良妊娠结局发生的独立危险因素(P<0.05);5个独立危险因素构建logistic回归模型方程为logistic(P)=-4.125+年龄×3.170+孕前BMI×2.773+阴道分娩×2.793+GDM×3.271+负性情绪×3.029;当logistic(P)=4.11,预测HDP患者发生不良妊娠结局的曲线下面积为0.899(95%CI:0.865~0.926),预测敏感度为84.36%,特异度为82.17%;根据设定的评分标准与不良妊娠结局发生情况,可将HDP患者划分为低风险(0~4分)、中风险(5~8分)与高风险(9~12分)。 结论 HDP患者不良妊娠结局发生率较高,年龄、孕前BMI、阴道分娩、GDM、负性情绪均为不良妊娠结局发生的影响因素,构建logistic回归模型可预测不良妊娠结局发生风险,有助于临床制定相关干预措施。  相似文献   
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