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41.
三磷酸腺苷结合盒运转体A1与颈动脉粥样硬化斑块的关系   总被引:4,自引:0,他引:4  
目的 探讨三磷酸腺苷结合盒运转体A1(ATP binding cassette transporter A1,ABCA1)在人颈动脉粥样硬化斑块中的表达变化及作用机制.方法 收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本(对照组),采用RT-PCR测定ABCA1 mRNA和视黄酸X受体α(RXRα)mRNA表达水平,并采用Western Blot检测ABCA1及RXRα的蛋白表达水平.24例人颈动脉粥样硬化斑块标本按病理分级,比较病理组织为Ⅲ级和Ⅰ级动脉粥样硬化组织间ABCA1 mRNA、RXRαmRNA表达水平及蛋白表达水平.结果 颈动脉粥样硬化斑块组的ABCA1 mRNA(0.79±0.04)和RXRα mRNA(0.73±0.04)表达与对照组相比上调,差异有统计学意义(P<0.05);ABCA1 mRNA与RXRα mRNA增加水平相关(P<0.05);颈动脉粥样硬化斑块的ABCA1蛋白表达(0.22±0.03)下调水平与对照组(0.53±0.03)相比差异有统计学意义(P<0.05);Ⅲ级和Ⅰ级动脉硬化斑块ABCA1mRNA、RXRα mRNA及蛋白表达水平差异有统计学意义(P<0.05).结论 ABCA1及RXRα蛋白表达水平下调可能是进展性动脉粥样硬化损害的关键因素.  相似文献   
42.
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members.  相似文献   
43.
Case report A 28-year-old female patient was admitted because of painlessmacroscopic haematuria. Past history included severe mentalretardation and nystagmus. At age 17, a computed tomography(CT) scan of the brain showed an absent cerebellar vermis andcerebellar hypoplasia. There was no  相似文献   
44.
Obstructive sleep apnea syndrome (OSAS) is a common condition characterized by repetitive sleep‐induced collapse of the upper airways. It is associated with increased risk for hypertension, ischemic heart disease, cerebral stroke, and traffic accidents. In contrast, gastroesophageal reflux disease (GERD) is a very common disorder defined as various symptoms or esophageal mucosal damage generated by the abnormal reflux of gastric contents into the esophagus. Patients with OSAS have been reported to have a high prevalence of gastroesophageal reflux (GER) symptoms. The increase of transdiaphragmatic pressure in parallel with the large negative intrathoracic pressure produced during apnea events may directly lead to GER. In addition, some studies have demonstrated improvement in GERD with the application of continuous positive airway pressure, most consistently effective treatment for OSAS. However, GER dose not occur with every apnea. Moreover, the common conditions observed in patients with OSAS, including obesity or alcohol ingestion, are also predisposing factors for GER. A more recent investigation in over 1000 subjects failed to show a causal link between both diseases. Thus, the potential relationship between OSAS and GERD remains controversial. Inconsistencies in definitions of both diseases or sampling biases may contribute to the confusing results.  相似文献   
45.
阿尔茨海默病患者脑白质损害与认知功能的关系   总被引:4,自引:0,他引:4  
目的用磁共振扩散张量成像(DTI)研究阿尔茨海默病(AD)患者脑白质损害的特点及其与认知功能改变的相关性。方法对16例AD患者和12名年龄及性别相当的健康老年人行DTI、T1液体衰减反转恢复序列(FLAIR)及T2-FLAIR检查,测量胼胝体膝部和压部、内囊前肢和后肢、额颞顶枕叶白质的部分各向异性分数值(FA)和平均弥散度(MD),分析FA、MD值与简易精神状态量表(MMSE)评分之间的相关关系。结果AD患者胼胝体压部、额叶、顶叶、颞叶FA值分别为0.602±0.043、0.270±0.034、0.294±0.043、0.302±0.032,与健康老人组相比显著下降(P<0.05),且与MMSE评分呈正相关关系,而内囊前后肢、枕叶、胼胝体膝部的FA值则无明显变化(P>0.05);胼胝体压部、顶叶白质的MD值分别为(0.918±0.029)、(0.826±0.015)×10-9m2/s,与健康老人组相比显著升高(P<0.01),且与MMSE评分呈负相关,而内囊前后肢、额叶、颞叶、枕叶和胼胝体膝部的MD值则无明显变化(P>0.05)。结论AD患者表现为脑白质的选择性损害,且损害程度与认知功能密切相关;这种选择性损害反映了AD病理机制中皮质-皮质及皮质-皮质下联系的丢失;DTI技术可以用来监测疾病的进展情况及评价AD治疗药物的临床疗效。  相似文献   
46.
Elderly men with clinical and laboratory evidence of androgen deficiency are eligible for testosterone treatment.

With proper monitoring this is acceptably safe.

In the first year of testosterone treatment there should be a digital rectal examination of the prostate and measurement of prostate specific antigen every three months, thereafter yearly.

The rate of increase of prostate specific antigen (PSA) levels is more significant than its absolute values.

Levels of haemoglobin and the haematocrit should be monitored.  相似文献   

47.
良性阵发性位置性眩晕的自我治疗   总被引:14,自引:2,他引:12  
目的比较改良的Epley耳石复位法(MEP)和改良的Semont耳石复位法(MSM)用于后半规管良性阵发性位置性眩晕(PC-BPPV)自我治疗的疗效。方法对2001年7月至2003年6月间的70例PC-BPPV患者分别使用MEP和MSM法进行自身治疗,1周后比较两组缓解率和治疗的副作用。结果MEP组中95%(n=37)患者完全缓解,而MSM组仅为58%(n=33,P〈0.001)。MSM组中,治疗的失败与动作执行的不准确密切相关。两组治疗有关的副作用差异无统计学意义。结论MEP比MSM能更有效的缓解PC-BPPV,MEP应为患者自身治疗的首选方法。  相似文献   
48.
The objective of this study is to assess the efficacy and safety of herbal medicines (HMs), as a monotherapy or adjunct therapy, compared to placebo or conventional approaches in the treatment of idiopathic Parkinson's disease (PD). We conducted a systematic review of randomized controlled trials from both conventional and alternative medicine sources. Outcome measures were overall improvement, quality of life, reduction of levodopa dose, and adverse events. Nine studies were included, each testing a different HM. Six of the trials had limited internal validity due to major flaws in design, including the lack of proper randomization; insufficient blinding; unclear inclusive criteria in terms of diagnostic criteria, baseline staging, and duration of disease; lack of proper sample size calculation; and insufficient data analysis. Imbalances in gender and ethnicity among the patients in the included trials were observed. No major adverse events emerged, and no specific pattern was detected from the trials describing such data. In addition to major methodological defects, heterogeneity in (1) HM tested, (2) control treatment, and (3) outcome measure hindered in-depth data analysis and synthesis. Current evidence is insufficient to evaluate the efficacy and safety of various HMs. Further studies with improved trial design and reporting, with assessment on cost-effectiveness, quality of life, and qualitative data are warranted.  相似文献   
49.
Intrastriatal transplantation of striatal neuroblasts from human fetuses is a promising approach for treatment of Huntington's disease, on the basis of many experimental animal studies and, most recently, pilot clinical trials. Technically, several issues remain to be resolved (e.g., the precise site of dissection of the fetal tissue; the number and location of the fetal striatal implants; or the use of immunosuppressive therapy), and await larger-scale trials and purposely designed protocols. Further clinical data must also be obtained, and preliminary promising results must be replicated in a patient group large enough to provide conclusive results. It is important to establish (1) the amount of clinical benefit provided to the patient by the grafted cells; (2) the anticipated duration of clinical benefits; and (3) the secondary rate of decline after the benefit of the graft has been overbalanced. Evaluation of these parameters will require very long-term follow-up of the patients involved, over several years after grafting, before the technique can eventually be proposed widely to patients.  相似文献   
50.
The aim of this pilot study was to examine the role of the striatum and cerebellum in the adaptation to a novel movement within a sequence of practiced movements using a motor learning paradigm. The performance of patients in the early or advanced stages of Parkinson's disease (PD) and of patients with damage to the cerebellum (CE) was compared, respectively to a group of aged and young matched controls on an adapted version of the Mirror-Tracing Test. In this task, subjects were required to trace a series of complex figures in two conditions: (1) a Practiced condition, in which the figures were composed of the juxtaposition of three simple designs that were extensively practiced before; and (2) a Mixed condition in which triads were created by replacing the last simple figure of the triads in the Practiced condition by a new simple figure that had never been traced individually before. Results showed that all clinical groups were slower than controls at tracing the Practiced triads. Most interestingly, however, only patients in the advanced stages of PD showed increased completion time to trace the triads in the Mixed condition. This suggests that a bilateral striatal dysfunction affects the ability to adapt to a novel motion within a sequence of practiced movements. Although exploratory, these results support a functional dissociation between the striatum and cerebellum in acquiring visuomotor skilled behaviors.  相似文献   
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