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   7890篇
  免费   321篇
  国内免费   542篇
耳鼻咽喉   78篇
儿科学   155篇
妇产科学   119篇
基础医学   993篇
口腔科学   108篇
临床医学   741篇
内科学   1292篇
皮肤病学   73篇
神经病学   332篇
特种医学   230篇
外国民族医学   39篇
外科学   750篇
综合类   1219篇
现状与发展   6篇
一般理论   2篇
预防医学   511篇
眼科学   212篇
药学   769篇
  7篇
中国医学   334篇
肿瘤学   783篇
  2024年   31篇
  2023年   107篇
  2022年   81篇
  2021年   76篇
  2020年   65篇
  2019年   57篇
  2018年   32篇
  2017年   29篇
  2016年   33篇
  2015年   59篇
  2014年   143篇
  2013年   90篇
  2012年   1075篇
  2011年   1146篇
  2010年   275篇
  2009年   123篇
  2008年   707篇
  2007年   745篇
  2006年   640篇
  2005年   576篇
  2004年   480篇
  2003年   403篇
  2002年   314篇
  2001年   183篇
  2000年   288篇
  1999年   168篇
  1998年   103篇
  1997年   93篇
  1996年   73篇
  1995年   70篇
  1994年   60篇
  1993年   55篇
  1992年   49篇
  1991年   35篇
  1990年   29篇
  1989年   35篇
  1988年   19篇
  1987年   22篇
  1986年   21篇
  1985年   23篇
  1984年   21篇
  1983年   18篇
  1982年   19篇
  1981年   8篇
  1980年   12篇
  1979年   10篇
  1965年   5篇
  1958年   5篇
  1957年   11篇
  1956年   9篇
排序方式: 共有8753条查询结果,搜索用时 15 毫秒
1.
正摘要目的利用多参数MR成像图谱和全肿瘤直方图分析三阴性(TN)乳腺癌与其他分子亚型鉴别的影像学生物标志。方法本回顾性研究包括134例浸润性导管癌病人。从  相似文献   
2.
应用微血管铸型扫描电镜技术研究8例成人肾脏的肾小球微血管构筑,结果发现:1.输入小动脉在肾小球血管极处分为2~5支小球内小叶微动脉。输入小动脉血管铸型的直径为126.35±20.5μm。2.肾小球是由小球内小叶微动脉、毛细血管、毛细血管网小叶间交通支和毛细血管输出根所构成的近似于球状体,小球内每个毛细血管网小叶均是一个独立的机能解剖学单位;3.299个肾小球均有一支输出小动脉,只有一个肾小球有两支输出小动脉。输出小动脉的血管铸型直径为91.35±11.7μm。4.输出小动脉起始处具有毛细血管前括约肌装置,此结构在调控肾小球内的微循环血流有着重要意义。  相似文献   
3.
Changes in T .lymphocyte subsets after severe traumatic brain inJury   总被引:2,自引:0,他引:2  
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections.  相似文献   
4.
目的:探讨心肌缺血后流经心脏的白细胞受剌激后释放白三烯C4(LTC4)能力的变化及基意义。方法:将12只犬随机分为2组。对照组(6只)犬开胸后冠状动脉(冠脉)不结扎,心肌缺血组(6只)犬开胸后结扎冠脉造成心肌缺血。2组分别于开胸后30分钟(结扎前)、实验结束时取冠状窦和动脉内血各15ml,分离出白细胞,用Calcium Ionophore A23187剌激后取上清液用放射免疫后释放的LTC4〔对照  相似文献   
5.
CT造影剂碘海醇注射液的制备及动物实验   总被引:3,自引:0,他引:3  
本文报道了非离子型X-CT造影剂碘海醇注射液的制备及动物实验结果。磺海醇的最大吸收波长λ_(max)为244nm。讨论了温度、浓度对磺海醇溶液粘度的影响:粘度随温度的升高而下降,呈负线型相关;粘度随浓度(C)升高而激剧升高,与浓度的四次方呈线性相关:V_(37℃)=472.589[C] ̄4+1.121(r=0.9977)V_(30℃)=663.813[C] ̄4+1.152(r=0.9996)V_(20℃)=1082.953[C] ̄4+1.433(r=0.9982)使用该注射液进行狗的造影实验,获得了清晰的造影图像。  相似文献   
6.
妇科千金片对宫颈糜烂治疗后阴道排液的疗效观察福建省第二人民医院(350003)郑怡真王宁娜宫颈糜烂是妇科常见病之一,临床上多采用冷冻、电烙、多功能光谱治疗等方法,但治疗后阴道排液多达4周左右,使患者普遍感到十分苦恼。我们从1996年9月开始,对采用多...  相似文献   
7.
热毒清抗内毒素所致溶酶体和线粒体损伤的实验研究   总被引:17,自引:0,他引:17  
  相似文献   
8.
INTRODUCTION Neuroglobin (NGB) is a recently discovered member of the vertebrate globin family [1], predominantly expressed in various brain regions of human and vertebrate. The expression of NGB was increased in case of ischemia, which may play a role in…  相似文献   
9.
According to traditional teaching mode, the courses in preclinical medicine including pharmacology are separately run. This mode causes a series of disadvantages including loose connection between knowledge in different disciplines and weak ability to bridge basic preclinical knowledge and clinical practice. In order to overcome the disadvantages and promote the teaching efficiency, we constructed a new integrated course-Course of Basic Medical Sciences, which includes 6 traditional courses, anatomy, histology and embryology, physiology, pathology, pathophysiology and pharmacology. We integrated these courses based on the human organ systems and according to the principle-" From macro to micro, From morphological to functional, From normal to abnormal and From disease to drug therapy" and published the series of textbook in 2004. The contents of pharmacology are taught just after pathology and pathophysiology in every organ system. In comparison with the traditional teaching mode, teachers of pharmacology need not spend a lot of time to review preceding knowledge of anatomy and histology, physiology, pathophysiology and pathology. This is helpful in saving time and improving the teaching efficiency.  相似文献   
10.
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