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   49851篇
  免费   2664篇
  国内免费   164篇
耳鼻咽喉   630篇
儿科学   3084篇
妇产科学   906篇
基础医学   6269篇
口腔科学   1216篇
临床医学   3526篇
内科学   9262篇
皮肤病学   1326篇
神经病学   2865篇
特种医学   1481篇
外国民族医学   1篇
外科学   7032篇
综合类   1667篇
一般理论   23篇
预防医学   2699篇
眼科学   1868篇
药学   4851篇
  1篇
中国医学   418篇
肿瘤学   3554篇
  2023年   386篇
  2022年   1131篇
  2021年   1898篇
  2020年   1002篇
  2019年   1144篇
  2018年   1621篇
  2017年   1173篇
  2016年   1526篇
  2015年   1560篇
  2014年   2265篇
  2013年   2638篇
  2012年   3683篇
  2011年   3659篇
  2010年   2160篇
  2009年   1732篇
  2008年   2520篇
  2007年   2586篇
  2006年   2386篇
  2005年   2080篇
  2004年   1968篇
  2003年   1699篇
  2002年   1468篇
  2001年   1061篇
  2000年   978篇
  1999年   815篇
  1998年   349篇
  1997年   277篇
  1996年   284篇
  1995年   238篇
  1994年   200篇
  1993年   177篇
  1992年   496篇
  1991年   475篇
  1990年   484篇
  1989年   454篇
  1988年   439篇
  1987年   360篇
  1986年   354篇
  1985年   350篇
  1984年   275篇
  1983年   188篇
  1982年   117篇
  1980年   107篇
  1979年   182篇
  1978年   138篇
  1977年   141篇
  1976年   119篇
  1974年   114篇
  1973年   129篇
  1971年   119篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Oral Submucous Fibrosis is an insidious, chronic disease affecting the oral cavity, sometimes the pharynx and rarely the tongue. 15 patients with Oral Submucous Fibrosis presenting with severe trismus were treated with lysis of the fibrotic bands with a KTP-532 Laser and adjunctive treatment with excellent results over a 12 month follow-up period.  相似文献   
102.
OBJECTIVE: To evaluate the procedure in terms of technical difficulties, patient satisfaction, symptom relief, recurrence, and further management. STUDY DESIGN: Retrospective study including 41 patients who underwent endoscopic stapling diverticulotomy. Clinical notes were reviewed, and patients were sent a patient satisfaction questionnaire. Statistical analysis was done using the chi(2) square test. SETTING: Teaching hospital. RESULTS: Larger pouches had the best results; 81.578% were satisfied with the surgery, and 86.84% had improved swallowing. Complications presented in 6 patients (15%), including a perforated pouch and an esophageal perforation. Complications were more frequent in small pouches. CONCLUSIONS AND SIGNIFICANCE: Endoscopic stapling diverticulotomy offers rapid recovery in most patients, with early oral intake and short hospital stay. There is a high degree of symptoms relief, and the patient's satisfaction rate is high. The assessment of the pharyngeal pouch size is an important factor when deciding the best management for a patient with a pharyngeal pouch.  相似文献   
103.
104.
Autologous bone marrow transplantation.   总被引:1,自引:0,他引:1  
  相似文献   
105.
Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.  相似文献   
106.
Complete dislocation of the lens is a rare feature of Marfan's Syndrome. We observed four cases of bilateral complete posterior dislocation of the lens in established cases of Marfan's Syndrome over a one year period. An ophthalmologist may encounter infrequently, unilateral posterior dislocation in one eye and ectopia lentis in the other, but bilateral spontaneous posterior dislocation is rare. All our cases had associated vitreous degeneration with vitreous herniating into the anterior chamber. The pathogenesis of complete posterior dislocation in Marfan's Syndrome is discussed.  相似文献   
107.
A cell line from Wilms' tumour with deletion in short arm of chromosome II   总被引:1,自引:0,他引:1  
A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.  相似文献   
108.
Distal metatarsal osteotomy for hallux valgus in the middle-aged patient   总被引:1,自引:0,他引:1  
Thirty-eight distal metatarsal osteotomies for hallux valgus in middle-aged patients between the ages of 50 and 67 years were performed over a period of five years. None of the patients could be rated with an excellent result. Good results were noted in only 52.6%. Poor results were attributable to imperfect surgical technique, severity of preoperative deformity, osteoporosis, and preexisting osteoarthritic changes at the first metatarsophalangeal joint.  相似文献   
109.
Eight healthy, young adult males underwent three separate, 10-min 70 degrees head-up tilts (HUT) over a period of nine days, in order to assess the intra- and inter-individual variability of cardiovascular and plasma norepinephrine (NE) responses to the manoeuvre. Cardiovascular parameters and plasma NE were measured in the basal state and at 2-min intervals during the HUT. The results indicate that: (1) the intra-individual variability is a smaller component of the total variability of both cardiovascular and plasma NE responses to HUT; (2) the variability in cardiovascular parameters is smaller than that in plasma NE levels, both basal and in response to postural stress; (3) there does not appear to be any difference in variability when expressed either as the maximal or the mean response to HUT; and (4) there does not appear to be an increase in the variability of the measured parameters over the duration of the HUT.  相似文献   
110.
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