首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   110028篇
  免费   10339篇
  国内免费   7246篇
耳鼻咽喉   791篇
儿科学   1456篇
妇产科学   1571篇
基础医学   12089篇
口腔科学   2025篇
临床医学   14304篇
内科学   15996篇
皮肤病学   1076篇
神经病学   5368篇
特种医学   3779篇
外国民族医学   39篇
外科学   9991篇
综合类   19829篇
现状与发展   34篇
一般理论   12篇
预防医学   8345篇
眼科学   2629篇
药学   12656篇
  124篇
中国医学   6785篇
肿瘤学   8714篇
  2024年   455篇
  2023年   1689篇
  2022年   4203篇
  2021年   5303篇
  2020年   4106篇
  2019年   3393篇
  2018年   3553篇
  2017年   3431篇
  2016年   3124篇
  2015年   4899篇
  2014年   6028篇
  2013年   5937篇
  2012年   8916篇
  2011年   9255篇
  2010年   6278篇
  2009年   5066篇
  2008年   6415篇
  2007年   6284篇
  2006年   5696篇
  2005年   5417篇
  2004年   3899篇
  2003年   3621篇
  2002年   3106篇
  2001年   2460篇
  2000年   2421篇
  1999年   2349篇
  1998年   1468篇
  1997年   1437篇
  1996年   1108篇
  1995年   1076篇
  1994年   877篇
  1993年   545篇
  1992年   601篇
  1991年   549篇
  1990年   477篇
  1989年   414篇
  1988年   332篇
  1987年   327篇
  1986年   263篇
  1985年   200篇
  1984年   127篇
  1983年   89篇
  1982年   63篇
  1981年   50篇
  1980年   36篇
  1979年   47篇
  1978年   18篇
  1974年   17篇
  1973年   17篇
  1966年   18篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.

Background

The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.

Objectives

The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.

Methods

PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.

Results

Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).

Conclusions

In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550)  相似文献   
3.
目的:探究原发性肝癌患者手术切除术后早期复发影响因素分析。方法:对广州市番禺区中医院2017年2月-2019年2月收治的原发性肝癌患者98例进行回顾性分析,依据各项临床指标分析手术切除术后早期复发的影响因素。结果:原发性肝癌患者经由手术切除后出现复发的可能性较高,同时手术切缘有残留、包膜不完整、肿瘤结节、心理因素、甲胎蛋白、血管侵犯、肝硬化及肿瘤直径等均是影响原发性肝癌手术期后再复发的高危因素。结论:原发性肝癌通常具有术后复发的生物学特性,依据对手术切除术之后早期复发因素的分析,对手术风险与治疗方案进行充分评估,同时要求患者进行定期复查及随访等工作,可对患者手术成功以及并发症的防治等均具有积极意义。  相似文献   
4.
5.
《新方八阵》补真阴与补真阳用药关联性研究   总被引:3,自引:0,他引:3  
用方剂计量学研究中的关联性分析法对《新方八阵》中补真阴、补真阳药物的应用与其他医家进行比较,印证了景岳重视阴中求阳、阳中求阴的思想,为方剂比较研究中关联指数与关联性分析的具体化内容之一。  相似文献   
6.
We report clinical, neuroradiologic features, and neuropathologic findings of a 76‐year‐old man with coexistent Pick’s disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bed‐ridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative. The patient died from pneumonia 16 years after the onset of symptoms. Serial MRI scans showed progressive cortex atrophy, especially in the bilateral frontal and temporal lobes. Macroscopic inspection showed severe atrophy of the whole brain, including cerebrum, brainstem and cerebellum. Microscopic observations showed extensive superficial spongiosis and severe neuronal loss with gliosis in the second and third cortical layers in the frontal, temporal and parietal cortex. There were Pick cells and argyrophilic Pick bodies, which were tau‐ and ubiquitin‐positive in neurons of layers II–III of the above‐mentioned cortex. Numerous argyrophilic Pick bodies were observed in the hippocampus, especially in the dentate fascia. In addition, moderate to severe loss of neurons was found with gliosis and a lot of Gallyas/tau‐positive globus neurofibrillary tangles in the caudate nucleus, globus pallidus, thalamus, substantia nigra, locus coeruleus and dentate nucleus. Numerous thorned‐astrocytes and coiled bodies but no‐tuft shaped astrocytes were noted in the basal ganglion, brainstem and cerebellar white matter. In conclusion, these histopathological features were compatible with classical Pick’s disease and coexistence with progressive supranuclear palsy without tuft‐shaped astrocytes.  相似文献   
7.
加强医疗仪器设备管理提高医疗仪器设备使用效益   总被引:1,自引:0,他引:1  
加强医疗设备管理,提高设备使用效益,制定合理的计划,正确选购设备,为医院提供品种、性能、精度适当的技术装备。  相似文献   
8.

Introduction  

Positive end-expiratory pressure (PEEP)-induced lung derecruitment can be assessed by a pressure–volume (P–V) curve method or by lung computed tomography (CT). However, only the first method can be used at the bedside. The aim of the study was to compare both methods for assessing alveolar derecruitment after the removal of PEEP in patients with acute lung injury or acute respiratory distress syndrome.  相似文献   
9.
了庐 《中医药文化》2006,1(2):10-10
在中国古代思想史上.“道”一直被人们视为是对认识客观世界最高境界的象征。以后又延伸到各个方面。  相似文献   
10.
OBJECTIVES: To determine whether aromatase expression in the eutopic endometrium and adenomyotic foci is affected by previous use of oral contraceptives containing gestodene, and to determine whether changes in cyclooxygenase-2 (COX-2) expression occur in adenomyosis during the menstrual cycle. PATIENT AND METHODS: This was a retrospective cohort study carried out in paraffin-embedded endometrial tissue obtained from patients with a histological diagnosis of adenomyosis obtained during the proliferative (n = 25) and luteal (n = 10) phases of the menstrual cycle and following the use of continuous oral contraception with gestodene/ethinyl estradiol (n = 7). COX-2 and aromatase expression were measured in both eutopic endometrium and adenomyotic foci using immunohistochemical methods. RESULTS: Aromatase expression was detected in 80% of the endometrial slices by immunohistochemistry. In positive cases, aromatase was mainly detected in the stromal cells of the eutopic endometrium, whereas in the adenomyotic foci this expression was negative in the majority of the cases. Oral contraceptives containing gestodene, on the other hand, were effective in suppressing aromatase expression in both eutopic and ectopic endometrium. COX-2 expression was detected by immunohistochemistry in the glandular epithelium of both eutopic endometrium and adenomyotic foci and there were no significant changes in its intensity throughout the menstrual cycle. CONCLUSION: Aromatase expression in the eutopic endometrium and adenomyotic foci is suppressed by oral contraceptives containing gestodene. Increased aromatase activity may be responsible for the persistent COX-2 expression during the luteal phase.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号