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81.
Abstract The aim of this study was to evaluate the short- to medium-term results (up to 2 years) of conservative and surgical treatments of patients with symptomatic lumbar stenosis. To our knowledge, no previous study has provided strict indications for conservative or surgical treatment. We retrospectively studied 184 patients, who were divided into 3 groups according to JOA (Japanese Orthopaedic Association) score. A cutoff JOA score was arbitrarily fixed at 7. Patients with a score ≤7 (n=12; group A) underwent surgery, while patients with a score >7 (n=172) were conservatively treated. Group A included patients surgically treated within two months from diagnosis. Group B consisted of 144 patients who received conservative treatment, while group C (28 patients) represented patients who underwent surgery after a period of failed conservative treatment. The outcomes of surgical and conservative treatments were evaluated after 12 and 24 months, and were rated as satisfactory, not totally satisfactory, not satisfactory or totally unsatisfactory. Conservative treatment consisted of physical, orthotic and drug therapy, whereas surgical treatment included spinal decompression and instrumentation (if indicated), either rigidly or dynamically performed. Surgery was indicated in 22% of all patients and we obtained excellent results in 85% of them. Operative treatment provides excellent results for patients with severe clinical presentation (JOA score ≤7), while individuals with mild to moderate spinal stenosis (JOA score >7) should receive conservative treatment.  相似文献   
82.
This article concerns the asymptotic properties of linkage tests for affected‐sib‐pair data under the null hypothesis of no linkage. We consider a popular single‐locus analysis model where the unknown parameters are the disease allele frequency, the three penetrances for the three genotypes at the disease locus, and the recombination fraction between the marker locus and the disease locus. These parameters are completely confounded under the null hypothesis of no linkage. We show that 1) If the total variance of the trait (i.e., the additive variance plus the dominance variance) is “separated” from 0, then the likelihood ratio statistic has an asymptotic 0.5χ20+ 0.5χ21 distribution; 2) If the prevalence of the trait is “separated” from 0 and the recombination fraction is fixed at 0, then the likelihood ratio statistic has an asymptotic distribution which is a mixture of χ20, χ21 and χ22 . The implications of these results are discussed.  相似文献   
83.
【摘要】
目的 调查与静止性脑梗死(silent brain infarction,SBI)相关的独立影响因素,构建SBI风险预测量
表并验证。
方法 在单中心横断面研究中,前瞻性连续纳入无神经系统疾病既往史的体检者,收集其人口学
信息,高血压、糖尿病等血管危险因素,血脂、糖化血红蛋白、血浆同型半胱氨酸等化验结果录入数
据库。采用标准影像学操作规范进行头颅MRI扫描,并由影像学医师盲法判读,将受试者分为SBI组
和无SBI组。将所有受试者按照3∶1比例随机分为训练集和验证集,在训练集中采用单因素和多因素
Logistic回归分析SBI的独立影响因素,构建SBI预测量表。在训练集和验证集中应用ROC曲线检验量表
的区分度,应用Hosmer-Lemeshow分析检验量表的校准度。
结果 共有633例研究对象纳入研究,平均年龄52.0±10.5岁,女性272例(43.0%)。训练集(475
例)和验证集(158例)两个样本集合的基线特征均衡。校正混杂因素后多因素分析显示,年龄≥45
岁(OR 8.37,95%CI 1.12~62.80,P =0.039),高血压(OR 2.30,95%CI 1.08~4.90,P =0.032),同型半
胱氨酸(Q2~Q3:OR 6.89,95%CI 0.89~53.10,P =0.064;Q4:OR 13.6,95%CI 1.74~105.87,P =0.013)
与SBI风险独立相关。根据OR 值构建SBI危险评分(SBI risk score,SBI-RS)量表,量表赋值为:年龄
≥45岁赋值8分;有高血压赋值2分;同型半胱氨酸根据四分位分层分别赋值为0分、7分和14分。SBIRS
在训练集和验证集中ROC曲线显示曲线下面积分别为0.77(95%CI 0.69~0.84,P<0.001)和0.76
(95%CI 0.63~0.88,P<0.001),区分度良好。Hosmer-Lemeshow相关分析提示SBI-RS具有较好的校准度
(P>0.05)。
结论 在健康体检人群中,SBI -RS具有较好的区分度和校准度,可以帮助识别SBI高危人群。  相似文献   
84.
The Pediatric End-Stage Liver Disease (PELD) score was designed to reduce subjectivity in liver allocation and to advantage patients with a higher probability of waiting list mortality. The aims of this study were to determine the impact of PELD implementation for children with chronic liver disease and to assess whether PELD met its goal of standardization of liver allocation for children. This study used data reported to the United Network for Organ Sharing (UNOS) registry for children with chronic liver disease receiving primary cadaveric liver transplant between January 2000 and December 2001 (pre-PELD) and March 2002 and July 2003 (PELD). PELD reduced the percentage of children transplanted while in an intensive care unit and as status 1. A calculated PELD score was used for allocation in only 52% of recipients. Thirty percent were status 1 at transplant and PELD scores granted by exception were used for allocation in 18% of patients. There was regional variation in PELD score at allocation and use of exception scores with a significant relationship between PELD score and percentage of exception cases. Regional variation suggests that PELD has not resulted in standardization of listing practices in pediatric liver transplantation.  相似文献   
85.
Abstract From our overall experience in 56 patients, we here report the treatment with matrix-induced autologous chondrocyte implantation (MACI) of 35 patients suffering from knee cartilage defects measuring about 4 cm2, and followed for a minimum of 6 months. A total of 36 knees were treated (1 patient on both knees) and clinically observed for 22 months (in some cases for over 39 months), in accordance with a standardised protocol. Subjective parameters (pain, well-being, functional state, symptoms during specific activity) and objective outcomes (IKDC score and Lysholm and Tegner scores) were recorded. One or 2 years after implantation, some biopsies of the regenerated cartilage were histologically evaluated. The subjective parameters (VAS pain score, 2.80±1.49, p<0.0001; change vs. basal score, 2.72) promptly normalized after 1 month, as did the objective ones (IKDC score after 6 months, 1.53±0.59, p<0.0001; change vs. basal score, 1.78). Similar results were observed after the treatment of a femoropatellar kissing lesion. The three cartilage biopsies that were analysed from different patients showed a tissue positivity to immunohistochemical markers of hyaline cartilage. The conclusions of this preliminary analysis are that the clinical outcome and histological evaluation suggest that MACI is able to relieve pain and restore the functionality of the knee, and that the treatment appears capable of regenerating hyaline cartilage.  相似文献   
86.
Fifty-four specimens from patients undergoing radical prostatectomy for clinically confined prostate cancer between 1983 and 1987 were reviewed to determine the potential for flow cytometric (FCM) analysis of DNA ploidy and replication rate to predict disease recurrence. Each specimen was deparaffinized for FCM analysis and the pathology slides were reviewed by a single pathologist. FCM characteristics were correlated with pathological grade and stage, and both were correlated with disease status. In this series of patients, routine FCM analysis of DNA ploidy and replication rate failed to significantly enhance the ability of standard histopathological grading to predict disease recurrence in patients having clinically localized prostate cancer. Aneuploid tumors pathologically confined to the prostate did not appear to negatively affect prognosis.  相似文献   
87.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。  相似文献   
88.
目的 研究多发创伤患者早期血清促卵泡生成素(FSH)、促黄体生成素(LH)变化与创伤严重度和格拉斯哥昏迷评分的关系.方法 随机选取2003年3月~2004年2月急诊就诊的多发创伤患者93例,就诊时间均在伤后24h内,即时采集血样,采用放射免疫双抗体沉淀法测定血清FSH、LH水平,并另选20名健康体检者作为对照组.93例患者按照ISS评分予以分组(ISS<16分47例,25≥ISS≥16分24例,ISS>25分22例),其中合并颅脑损伤者按GCS评分分组ISS<16分14例,25≥ISS≥16分14例,ISS>25分12例,并比较各分组间FSH、LH水平.结果 严重创伤组(ISS>25分)与合并颅脑损伤组患者早期FSH、LH明显升高(P<0.01).ISS>25分组、25≥ISS≥16分组、ISS<16分组血清FSH、LH水平依次降低(P<0.05或0.01),且前2组明显高于对照组(P<0.01).合并颅脑损伤者中,GCS>8分组、8≥GCS>5分组、5≥GCS≥3分组血清FSH、LH水平依次降低,组间比较差异有显著性(P<0.05或0.01),且均显著高于对照组(P<0.05或0.01).结论 血清垂体前叶激素FSH、LH水平的改变与严重创伤、颅脑损伤的严重程度相关,可作为判断伤情、观察预后的参考指标.  相似文献   
89.
Rockall危险性积分在急性上消化道出血中的应用   总被引:2,自引:0,他引:2  
赵毅  陆志平  曹剑凡 《现代医药卫生》2007,23(11):1598-1599
目的:探讨Rockall危险性积分在急性上消化道出血中的应用。方法:262例按Rockall危险性积分进行评分,并分为低危组(0~3)、中危组(4~7)、高危组(≥8)。结果:高危组与中危组相比再出血率差异无统计学意义(P〉0.05)。高危组与中危组相比死亡率明显升高(P〈0.05)。结论:Rockall危险性积分对急性上消化道出血患者的病情评估具有重要的意义。  相似文献   
90.
336例创伤数据对中国人创伤评分权重系数的评价   总被引:1,自引:0,他引:1  
目的为了评价国内对TRISS评分权重系数的修订,对336例创伤患者分别用国外权重和国内权重评定伤情后进行比较。方法336例采用TRISS法计算生存概率Ps,所需权重分别采用新近报道的国内权重和国外MTOS权重。Ps≥0.5预测生存,Ps<0.5预测死亡,将预测生死与实际生死结果进行比较。结果中国人权重在敏感性和区别度方面高于国外权重,误判率低于国外权重。结论中国人权重对中国人的创伤程度评估有价值,为进一步精确修订权重,建议建立大型中国人创伤数据库  相似文献   
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