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   20059篇
  免费   1285篇
  国内免费   79篇
耳鼻咽喉   183篇
儿科学   641篇
妇产科学   336篇
基础医学   2309篇
口腔科学   680篇
临床医学   2196篇
内科学   4630篇
皮肤病学   309篇
神经病学   1947篇
特种医学   851篇
外科学   2897篇
综合类   155篇
一般理论   7篇
预防医学   1231篇
眼科学   423篇
药学   1257篇
中国医学   19篇
肿瘤学   1352篇
  2023年   134篇
  2022年   239篇
  2021年   502篇
  2020年   281篇
  2019年   436篇
  2018年   543篇
  2017年   383篇
  2016年   445篇
  2015年   542篇
  2014年   675篇
  2013年   829篇
  2012年   1344篇
  2011年   1351篇
  2010年   788篇
  2009年   650篇
  2008年   1222篇
  2007年   1235篇
  2006年   1160篇
  2005年   1086篇
  2004年   885篇
  2003年   859篇
  2002年   739篇
  2001年   401篇
  2000年   388篇
  1999年   447篇
  1998年   185篇
  1997年   171篇
  1996年   131篇
  1995年   123篇
  1994年   98篇
  1993年   85篇
  1992年   236篇
  1991年   244篇
  1990年   217篇
  1989年   214篇
  1988年   184篇
  1987年   177篇
  1986年   164篇
  1985年   166篇
  1984年   148篇
  1983年   103篇
  1982年   81篇
  1981年   77篇
  1980年   83篇
  1979年   127篇
  1978年   76篇
  1977年   58篇
  1976年   67篇
  1975年   57篇
  1974年   58篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Two children with unusual extramedullary common acute lymphoblastic leukemia antigen (CALLA)-positive (CD10) disease are reported. Isolated masseter infiltration with CD10/CD19-positive lymphoblasts was present in both patients with no other evidence of disease. One child had relapse of common acute lymphoblastic leukemia, and the other had primary disease. Disease may have spread from lymph nodes overlying the masseter muscle. Immunophenotyping and immunogenotyping provided a rapid and accurate diagnosis for both children.  相似文献   
62.
BACKGROUND: Spironolactone is useful in heart failure, but is not given to dialysis patients for fear of hyperkalaemia. This study evaluated the safety of spironolactone administration in haemodialysis patients. METHODS: Fifteen haemodialysis outpatients with mean serum potassium <5.6 mEq/l over the preceding 4 months were treated with spironolactone 25 mg daily for 28 days. Serum potassium was measured before every haemodialysis during the study. Aldosterone and renin were measured at the beginning and end of the study. Patients were monitored for side effects. Data were examined with a paired t-test, with patients serving as their own controls and P < 0.05 considered significant. A sample size of 14 was required to achieve a power of 0.8 and a P = 0.05 to detect a potassium difference of 0.5 +/- 0.6 mEq/l. All patients were analysed as intention-to-treat. RESULTS: The mean potassium level was 4.6 +/- 0.6 mEq/l at baseline and 4.9 +/- 0.9 mEq/l at study completion (P = 0.14). Thirteen patients completed the trial with no potassium levels >6.0 mEq/l. Four patients had potassium levels between 5.5 and 6.0 mEq/l. One patient was withdrawn at day 20 after developing hyperkalaemia (7.6 mEq/l). Another patient was withdrawn at day 25 after missing a dialysis treatment. There were no differences in either baseline or 28 day aldosterone or renin levels (16.8 +/- 28.8 vs 11.7 +/- 6.1 ng/dl and 3.5 +/- 3.9 vs 3.5 +/- 3.5 ng/ml/h, respectively). Infrequent side effects included dry mouth, nosebleed, pruritis, gynecomastia and diarrhoea. No significant leukopenia or anaemia was noted. CONCLUSIONS: Spironolactone may be considered as a treatment option for selected chronic haemodialysis patients with heart disease.  相似文献   
63.
64.
The 5-HT1 receptor agonist, sumatriptan, is highly effective in the treatment of migraine. Some patients, however, do not respond or experience recurrence of the headache. In addition, some patients report chest symptoms after sumatriptan. We investigated whether these different responses could be attributed to genetic diversity of the 5-HT1B receptor, which most likely mediates the therapeutic action and the coronary side effects of sumatriptan. Allele frequencies of two polymorphisms in the 5-HT1B receptor gene ( G861C and T-261G ) were investigated in migraine patients with consistently good response to sumatriptan (n=14), with no response (n=12), with recurrence of the headache (n=12), with chest symptoms (n=13), and in patients without chest symptoms (n=27). Allele frequencies (G:0.74; C:0.26 at nt 861 and T:0.39; G:0.61 at nt -261) did not differ between patient groups, indicating that genetic diversity of the 5-HT1B receptor does not seem to be involved in the different clinical responses to sumatriptan.  相似文献   
65.
66.
Objective: To assess the impact of early corrective surgery on the short and medium term outcome in tetralogy of Fallot (TOF). Materials and methods: All patients under 12 months of age undergoing correction of isolated TOF between February 1997 and July 2003 were reviewed retrospectively. Outcome data for mortality, post-operative care management, major morbidity and clinical follow-up were analysed. Results: Fifty-two operations were performed. The mean age at surgery was 5 months (range 1–12) of whom 16 (30.8%) were less than 3 months old, including 2 neonates, 22 (42.3%) were 3–6 months old and 14 (26.9%) were 7–12 months old. There was 1 (1.9%) early death caused by a cerebro-vascular accident and 1 (1.9%) late death secondary to acute infective endocarditis. There were no differences in post-operative morbidities attributable to age. Patients under 3 months old required greater duration of post-operative ventilation, ITU stay and in-hospital stay. At a mean follow-up of 4.0 years (range 1.5–8.0), 33 (63.5%) patients had well-tolerated pulmonary regurgitation (PR) and 3 (5.8%) patients required re-operation for right ventricular outflow tract obstruction (RVOTO). All patients had right bundle-branch-block but with QRS < 150 ms. Conclusion: Early definitive repair of TOF can be performed safely on patients under 6 months old. Age at surgery does not appear to affect the medium term haemodynamic outcome. However, early surgery does escalate the need for ICU care. This data suggests repair in asymptomatic patients be delayed until 3–6 months of age.  相似文献   
67.
68.
69.
Laparoscopic bilateral adrenalectomy following failed hypophysectomy   总被引:1,自引:1,他引:0  
Background: Laparoscopic adrenalectomy has recently been shown to be a safe and effective means of treating adrenal pathology with much lower morbidity than the traditional approach. The majority of reports in the literature involve removal of adrenal tumors. Although open bilateral adrenalectomy has been utilized for persistent Cushing's syndrome following attempted hypophysectomy, there is little data available describing the application of laparoscopic adrenal surgery to this problem. Methods: Four patients with persistent Cushing's syndrome after attempted treatment with hypophysectomy underwent laparoscopic bilateral adrenalectomy at our institution. One procedure was done transabdominally in the supine position. Three procedures were done transabdominally using sequential lateral decubitus positions. Results: All procedures were completed laparoscopically. The mean operative time was 4.6 h (range 3.9–5.25). Repositioning and reprepping the patients resulted in a slight increase in operative time, but visualization was improved using the lateral decubitus position. Average blood loss: 156 cc (range 50–300). One patient required early reoperation for bleeding from the left adrenal bed, which was controlled laparoscopically. Three patients were eating the following day and were discharged on postoperative days 1, 2, and 5. The fourth patient remained hospitalized for 18 days due to problems unrelated to surgery. After a mean follow-up of 10 months, all patients have done well and have no clinical or biochemical evidence of recurrent disease. Conclusion: Our clinical experience indicates that laparoscopic bilateral adrenalectomy is a viable treatment option for Cushing's syndrome following failed hypophysectomy. Received: 29 March 1996/Accepted: 12 June 1996  相似文献   
70.
Flat adenomas in a colon cancer-prone kindred   总被引:9,自引:0,他引:9  
We describe new pathologic findings in a hereditary nonpolyposis colorectal cancer family. Affected family members developed multiple small adenomas with right-sided predominance; many adenomas had an unusual appearance featuring slightly elevated lesions with adenomatous changes confined to the upper regions of the colonic crypts. We have adopted the previously established term "flat adenoma" for these lesions. This phenotype may be a morphologic marker for at least one subset of hereditary nonpolyposis colorectal cancer.  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