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   107162篇
  免费   7629篇
  国内免费   4484篇
耳鼻咽喉   1388篇
儿科学   1357篇
妇产科学   1259篇
基础医学   13433篇
口腔科学   2011篇
临床医学   11093篇
内科学   16950篇
皮肤病学   2216篇
神经病学   5686篇
特种医学   5215篇
外国民族医学   21篇
外科学   11494篇
综合类   13030篇
现状与发展   28篇
一般理论   21篇
预防医学   6638篇
眼科学   3238篇
药学   10713篇
  89篇
中国医学   4325篇
肿瘤学   9070篇
  2024年   1101篇
  2023年   1508篇
  2022年   3124篇
  2021年   4544篇
  2020年   3253篇
  2019年   3178篇
  2018年   3312篇
  2017年   2991篇
  2016年   3287篇
  2015年   4705篇
  2014年   5821篇
  2013年   5843篇
  2012年   8730篇
  2011年   9017篇
  2010年   5783篇
  2009年   4992篇
  2008年   6391篇
  2007年   6061篇
  2006年   5733篇
  2005年   5130篇
  2004年   3920篇
  2003年   3788篇
  2002年   3168篇
  2001年   2221篇
  2000年   1932篇
  1999年   1671篇
  1998年   933篇
  1997年   823篇
  1996年   682篇
  1995年   636篇
  1994年   609篇
  1993年   418篇
  1992年   537篇
  1991年   514篇
  1990年   426篇
  1989年   395篇
  1988年   292篇
  1987年   324篇
  1986年   249篇
  1985年   194篇
  1984年   131篇
  1983年   109篇
  1982年   76篇
  1981年   57篇
  1980年   66篇
  1979年   78篇
  1975年   45篇
  1974年   44篇
  1973年   46篇
  1972年   43篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
Strong multiple reactions often occur with the Phadebact Streptococcus test when the culture contains blood. These reactions interfere with the identification of the Lancefield groups of streptococci. Group B streptococci from the vagina of pregnant women are difficult to identify by slide coagglutination because of the frequent presence of blood on culture swabs. Elimination of these multiple reactions caused by blood would permit rapid identification of group B streptococci in pregnant women. Vaginal broth cultures were examined to determine the cause of multiple reactions with slide coagglutination and to eliminate them from the testing procedure. Of 245 maternal broth cultures, 135 (55%) yielded multiple reactions when tested by coagglutination. Such reactions were either eliminated or greatly diminished by heating the broth sample to 90 degrees C for 10 min. It was also found that globulins in the serum may be responsible for multiple reactions with blood. This heating protocol will permit vaginal broth cultures to be rapidly tested for group B streptococci by slide coagglutination.  相似文献   
53.
综合ICU中低年资护士培训方法探讨   总被引:1,自引:0,他引:1  
目的探讨为综合ICU培养合格的护理人员的方法。方法根据ICU护士应具备的素质及低年资护士的特点,采用定期集中培训、一对一带教、参加护理查房等方法,对基础理论和基本技能进行强化,重点加强了ICU专科护理知识地训练。结果通过客观考核和主观考核,效果良好。结论经过为期12个月两个时段较规范的岗位培训,低年资护士能较好的适应ICU工作。  相似文献   
54.
Effect of aging on neuroglobin expression in rodent brain   总被引:5,自引:0,他引:5  
Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.  相似文献   
55.
Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor. Reported herein is a case of LGFMS arising in the big toe. The patient was a 58-year-old man who underwent excision of the tumor. The tumor was well-demarcated. Histologically, there were proliferating spindle-shaped tumor cells arranged in a whorled growth pattern, and the stroma showed hyalinized collagen bundles and a myxoid matrix. Nuclear mitotic figures were conspicuous in part. A large rosette-like structure with hyalinized stroma was found, which is characteristic of LGFMS. The differential diagnosis included tumor occurrence in adults; tending to arise in distal extremities; and having bland fibromyxoid histological features, such as fibroma of tendon sheath, low-grade myxofibrosarcoma and acral myxoinflammatory fibroblastic sarcoma. It was not possible to detect the FUS/CREB3L2 and FUS/CREB3L1 fusion genes from the formalin-fixed and paraffin-embedded tissue, although the histological features of the present case were typical of LGFMS. LGFMS may become more common with time, and unique cases may accumulate.  相似文献   
56.
Pathological survey of lung cancer induced by tin mine dust in Yunnan   总被引:2,自引:0,他引:2  
Pathological changes of lung cancer in miners of Yunnan Tin Mine were studied, and additionally, mineral dust in the miners' lung were also investigated by using scanning electronic microscope, energy disperse X-ray spectrometer and electronic probe. The results showed: 1. mineral dust caused active hyperplasia, atypical hyperplasia, metaplasia and atypical metaplasia of the epithelial of alveoli and bronchi, which was able to induce cancer. 2. Pneumoconiosis-like changes in the miner's lung are correlated with the high incidence of lung cancer. 3. Correlated also with copper, lead, zinc and iron may be the high incidence of lung cancer. 4. Transition form from hyperplasia and atypical hyperplasia of alveolar epithelia to malignancy was observed. It suggests that lung squamous cell carcinoma probably originates from the alveolar epithelia of the lung.  相似文献   
57.
Here we describe a 5-year-old girl with Gillespie syndrome of cerebellar ataxia, partial aniridia, and mental retardation. The Gillespie syndrome probably is an autosomal recessive trait.  相似文献   
58.
Radiation proctitis is a frequent acute complication encountered with pelvic irradiation. This study was aimed at establishing the optimal radiation dose for radiation-induced proctitis in rats. Female Wistar rats were used. The rectal specimens were examined morphologically at 5th and 10th day following 10-30 Gy irradiation in single fraction. With increasing dose, mucosal damage became worse, and there was a prominent reaction after > or =15 Gy. We selected 17.5 Gy as an optimal dose for radiation proctitis and examined specimens at day 1-14 and at week 4, 6, 8, and 12 after 17.5 Gy. The rectal mucosa revealed characteristic histological changes with time. An edema in lamina propria started as early as 1-2 days after irradiation and progressed into acute inflammation. On day 7 and 8, regeneration was observed with or without ulcer. Four weeks later, all regeneration processes have been completed with end result of either fibrosis or normal appearing mucosa. This study showed that the radiation injury of the rectum in rat develops in dose-dependent manner as it has reported in previous studies and suggested that 17.5 Gy in single fraction is the optimum dose to evaluate the protective effect of various medications for radiation proctitis in face of the clinical situation.  相似文献   
59.
冠脉内支架临床发展策略   总被引:1,自引:0,他引:1  
冠脉内支架是临床上预防PTCA并发症的有效措施,但金属支架固有的血栓菜成原性和对血管壁组织的永久性刺激可导致院内心脏事件和再狭窄。为解决上述问题,作者提出,血管内支架联合靶向药物传输离子照射或基因治疗、基因修饰的内皮细胞的种植支架、吱物可吸收缓释药物支架材料研制为临床冠脉内支架开辟了广阔的发展前景。  相似文献   
60.
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