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1.
目的系统评价脑白质疏松在卒中复发风险预测中的价值。方法计算机检索Pub Med、Web of science、Embase及维普、中国生物医学文献数据库、中国知网等数据库截止2019年3月15日收录的关于脑白质疏松及卒中复发关系的文献。提取资料进行质量评价并进行meta分析,利用Begg’s漏斗图和Egger’s检验评估发表偏倚。结果最终纳入33篇文献,共34444例。meta分析显示,当结局指标为任何类型复发性卒中时,中重度组与轻度或无组比较(RR=1. 71,95%CI:1. 44~2. 04),I~2=55. 69%;有脑白质疏松组与无脑白质疏松组比较(RR=1. 79,95%CI:1. 43~2. 25),I~2=56. 26%;连续性分析组(RR=1. 81,95%CI:1. 47~2. 23),I~2=34. 63%。当结局指标为缺血性卒中时,中重度组与轻度或无脑白质疏松组比较(RR=1. 82,95%CI:1. 36~2. 42),I~2=48. 43%;有脑白质疏松组与无脑白质疏松组比较(RR=2. 13,95%CI:1. 37~3. 32),I~2=70. 64%;连续性分析组(RR=2. 01,95%CI:1. 13~3. 58),I~2=69. 78%。亚组分析结果显示脑白质疏松对于远期复发性卒中的预测价值更高。通过Begg’s漏斗图和Egger’s检验,仅当结局指标为任何类型复发性卒中时,中重度组与轻度或无脑白质疏松组比较有显著性发表偏倚,经剪补法校正后仍提示相关性。结论脑白质疏松对于复发性卒中具有预测价值。  相似文献   
2.
目的:探讨脑白质疏松症(LA)患者睡眠障碍的影响因素。方法选择90例符合 MRI 诊断标准的 LA 患者(LA组)和90例性别、年龄相匹配的正常老年人(NC 组)作为研究对象;通过询问病史调查血管危险因素,采用匹兹堡睡眠质量指数(PSQI)量表评定睡眠障碍情况,依据头颅 MRI 表现将 LA 组分为4个等级。结果 LA 组高血压和糖尿病发生率显著高于 NC 组(P <0.05),LA 组 PSQI 评分显著高于NC 组(P <0.01)。LA 组随着 LA 分级升高,PSQI 评分依次增高(P <0.05)。回归分析显示,年龄、高血压、糖尿病、蒙特利尔认知评估量表等与 LA 患者睡眠障碍有关。结论LA 患者存在睡眠障碍,与 LA 病变程度、认知损害、年龄、高血压、糖尿病等密切相关。  相似文献   
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OBJECTIVES: To study the relation between serum levels of carotenoids and white matter lesions (WMLs) on magnetic resonance imaging (MRI). DESIGN: Evaluation of cross-sectional data from a cohort study. SETTING: The Rotterdam Scan Study. PARTICIPANTS: Two hundred and three nondemented older persons, age 60 to 90, from the Rotterdam Scan Study. MEASUREMENTS: Serum levels of carotenoids were determined. WMLs on MRIs were rated separately into periventricular and subcortical WMLs. Odds ratios (ORs) for the presence of severe WMLs (upper decile) were calculated per standard deviation (SD) increase in serum carotenoid level and per SD increase in overall carotenoid serum level. Effect modification by smoking status was studied through stratified analyses. RESULTS: Increasing levels of all the separate carotenoids were associated with less severe periventricular WMLs, which reached statistical significance for the overall carotenoid serum level (OR 0.4 per SD; 95% confidence interval (CI) = 0.2-0.9). We found no association between carotenoid levels and the presence of severe subcortical WMLs (OR 1.2 per SD; 95% CI = 0.7-2.0). The association of carotenoid levels with severe periventricular WMLs was more marked in those who ever smoked (OR 0.1 per SD; 95% CI = 0.0-0.9) than in those who had never smoked (OR 0.9 per SD; 95% CI = 0.4-2.1). CONCLUSIONS: These findings are compatible with the view that high levels of carotenoids may protect against WMLs in the periventricular region, in particular in smokers. Longitudinal studies with repeated measurements of both carotenoids and WMLs are necessary to explore this hypothesis further.  相似文献   
6.
Background: The purpose of the present study was to investigate the possible contribution of plasma homocysteine to asymptomatic cerebral infarction (CI) or leukoaraiosis. Methods: The relationship between plasma homocysteine concentrations and cerebral lesions was investigated in 233 elderly diabetic patients (mean age: 74 years) who were divided into three groups based on the neurological and brain MR findings: asymptomatic cerebral infarction (CI), symptomatic CI, and a control group with no evidence of cerebrovascular disease. Plasma total homocysteine concentrations were measured by high‐performance liquid chromatography. The C677T polymorphism in the methylene tetrahydrofolate reductase (MTHFR) gene was assessed by PCR‐RFLP. The total score of T2 high‐intensity lesions on the brain MR images was summed from the focal T2 high‐intensity scores in 24 areas of the brain. Results: Diabetic patients with asymptomatic or symptomatic CI had significantly higher homocysteine concentrations in plasma than the control group. The plasma homocysteine concentration was more strongly associated with the presence and number of small infarctions or infarction of the putamen, which may explain the association between increased plasma homocysteine concentrations and asymptomatic CI in elderly diabetic patients. In the diabetic patients, high plasma homocysteine concentrations were also significantly associated with high scores of total T2 high‐intensity lesions or focal T2 high‐intensity scores in some periventricular regions. Although there was no significant relationship between the MTHFR TT genotype and CI, a significant association was found between the MTHFR TT genotype and total T2 high‐intensity scores. Conclusion: An elevated plasma homocysteine concentration is independently associated with asymptomatic CI and T2 high‐intensity lesions on brain MR images in elderly patients with diabetes mellitus. The association between the MTHFR TT genotype and periventricular T2 high‐intensity lesions, but not with CI, suggests an important effect of C677T MTHFR gene mutation on leukoaraiosis, independent of hyperhomocysteinemia in elderly diabetic patients.  相似文献   
7.
伴脑白质疏松的脑梗死患者脑小动脉定量研究   总被引:2,自引:0,他引:2  
目的研究伴和不伴有脑白质疏松(LA)的高血压脑梗死患者,白质不同外径脑小动脉硬化程度的差异。方法通过病理学观察13例伴LA的高血压脑梗死患者(LA组)和10例不伴LA的高血压脑梗死患者(非LA组)脑小动脉病理变化。两组脑小动脉外径大小按30~100μm及101~300μm进行硬化指数定量分析。结果LA组不同外径脑小动脉硬化指数比较,30~100μm小动脉硬化指数明显高于101~300μm的小动脉(P=0.030)。非LA组不同外径脑小动脉硬化指数差异无统计学意义(P=0.617)。LA组30~100μm和101~300μm小动脉硬化指数分别显著高于非LA组。结论伴LA的高血压脑梗死患者白质脑小动脉硬化程度明显高于不伴LA的高血压脑梗死患者;小动脉外径越小,硬化程度越高。  相似文献   
8.
Disrupted blood–brain barrier (BBB) in patients with ischemic stroke plays a critical role in malignant middle cerebral artery infarction (MMI) development.Cerebral white matter changes (WMC), particularly in the deep subcortical area or in severe one, may be also underlain by disrupted BBB. It is unclear whether the presence of WMC with potential premorbid disruption of BBB makes patients susceptible to MMI. Therefore, this study aimed to clarify any putative relationship between the MMI and WMC in terms of their severity and locations.In this case–control study, patients with infarction in the middle cerebral artery territory were retrospectively reviewed. Brain magnetic resonance images were analyzed according to Fazekas scale, and identified WMC were divided into periventricular WMC (PV-WMC) and deep subcortical WMC (deep-WMC). Patients were scored as having WMC, PV-WMC, deep-WMC, severe PV-WMC, and severe deep-WMC according to the severity and locations. Patients were defined as having MMI if either a progressive conscious disturbance or signs of uncal herniation was recorded in combination with a midline shift >5 mm identified on the follow-up computed tomography.Among 297 patients admitted between July 2009 and February 2015, 92 patients were eligible for final analysis. Compared to patients without MMI, patients with MMI had a higher score of National Institutes of Health Stroke Scale, a larger infarct volume, and an increasingly greater proportion of severe PV-WMC, deep-WMC, and severe deep-WMC, respectively. After adjustment for sex, age, infarct volume, and history of hypertension, severe deep-WMC (odds ratio [OR] = 6.362, 95% confidence interval [CI] = 1.444–28.023, P = .0144) and severe PV-WMC (odds ratio = 5.608, 95% confidence interval = 1.107–28.399, P = .0372) were significantly associated with MMI development.MMI and WMC are significantly associated such that MMI development is more likely when PV-WMC or deep-WMC is more severe. We hypothesize that Fazekas scale-defined severe deep-WMC and PV-WMC may be considered as clinically approachable predictors of MMI development. These findings support that the WMC with potential premorbid disrupted BBB may make patients susceptible to MMI, and further prospective study should be conducted to clarify this hypothesis.  相似文献   
9.
老年人脑白质疏松与认知功能的关系   总被引:1,自引:0,他引:1  
目的 探讨脑白质疏松(LA)对老年人认知功能的影响。方法 对照113例老年人的简易智能状态检查(MMSE)评分和头颅MRI的LA表现,统计分析两者间的相关性。结果 LA程度随年龄增长逐渐加重,LA程度与认知功能减退有明显的相关。结论 LA是与年龄有关的引起认知功能衰退的风险因子。  相似文献   
10.
目的:探究糖代谢异常对慢性缺血性脑白质疏松(LA)的影响。方法回顾性分析2013年6月~12月中国医科大学附属第四医院神经内科收治的258例缺血性脑血管疾病患者的临床资料。根据病史及化验结果将糖代谢情况分为正常糖代谢、2型糖尿病以及前驱期糖尿病,依据头MRI结果对LA严重程度进行分级,分析比较不同糖代谢情况以及不同血糖化验指标(包括FPG、2hPG及HbA1c)对慢性缺血性脑白质疏松及其严重程度的影响。结果单因素分析显示,慢性缺血性脑白质疏松的相关危险因素有年龄、高血压病史、糖尿病病史、糖代谢异常、甘油三酯、2hPG(OR>1,P<0.05)。Logistic回归分析显示脑白质疏松与年龄、高血压病史、2hPG相关(P<0.05)。Spearman秩相关检验显示LA严重程度分级与年龄大小、高血压病史时长、2hPG水平呈正相关,与HDL、apoA、腔梗病史呈负相关(P<0.05,r=0.402、0.227、0.135、-0.154、-0.147、-0.312)。结论年龄、高血压病史、糖尿病病史、糖代谢异常、2hPG、甘油三酯是脑白质疏松的危险因素;年龄越大、高血压病史时间越长、2hPG越高、HDL及apoA越低,脑白质疏松越严重;而FPG、HbA1c、前驱期糖尿病、糖尿病及其时长与脑白质疏松的严重程度无相关性。  相似文献   
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