全文获取类型
收费全文 | 24669篇 |
免费 | 1209篇 |
国内免费 | 81篇 |
专业分类
耳鼻咽喉 | 332篇 |
儿科学 | 1380篇 |
妇产科学 | 604篇 |
基础医学 | 2725篇 |
口腔科学 | 557篇 |
临床医学 | 1409篇 |
内科学 | 5211篇 |
皮肤病学 | 772篇 |
神经病学 | 1509篇 |
特种医学 | 780篇 |
外科学 | 3179篇 |
综合类 | 759篇 |
一般理论 | 15篇 |
预防医学 | 1228篇 |
眼科学 | 1391篇 |
药学 | 2240篇 |
中国医学 | 179篇 |
肿瘤学 | 1689篇 |
出版年
2023年 | 171篇 |
2022年 | 424篇 |
2021年 | 864篇 |
2020年 | 424篇 |
2019年 | 550篇 |
2018年 | 705篇 |
2017年 | 487篇 |
2016年 | 608篇 |
2015年 | 568篇 |
2014年 | 910篇 |
2013年 | 1111篇 |
2012年 | 1568篇 |
2011年 | 1711篇 |
2010年 | 910篇 |
2009年 | 756篇 |
2008年 | 1171篇 |
2007年 | 1220篇 |
2006年 | 1224篇 |
2005年 | 1050篇 |
2004年 | 960篇 |
2003年 | 820篇 |
2002年 | 749篇 |
2001年 | 700篇 |
2000年 | 701篇 |
1999年 | 557篇 |
1998年 | 227篇 |
1997年 | 164篇 |
1996年 | 142篇 |
1995年 | 149篇 |
1994年 | 114篇 |
1993年 | 99篇 |
1992年 | 367篇 |
1991年 | 370篇 |
1990年 | 338篇 |
1989年 | 328篇 |
1988年 | 284篇 |
1987年 | 251篇 |
1986年 | 234篇 |
1985年 | 232篇 |
1984年 | 171篇 |
1983年 | 135篇 |
1981年 | 91篇 |
1979年 | 157篇 |
1978年 | 97篇 |
1977年 | 81篇 |
1975年 | 83篇 |
1974年 | 100篇 |
1973年 | 92篇 |
1972年 | 118篇 |
1970年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
D L Delaware M S Sharma B S Iyengar W A Remers T A Pursiano 《The Journal of antibiotics》1986,39(2):251-258
Dihydrostreptomycin analogues with structural variations in their guanidino groups were prepared. The analogue with a methyl group on the guanidine at C-1 was nearly as active as dihydrostreptomycin against bacteria. However, the 2-imidazolin-2-ylamino substituent at C-1 eliminated activity. No analogue with a substituent on the C-3 guanidino group was active. 相似文献
42.
Yashpaul Sharma S. B. S. Mann R. J. Dash Y. N. Mehra 《Indian journal of otolaryngology and head and neck surgery》1987,39(4):163-166
This study was undertaken to record the Brainstem Evoked Responses in a group of 20 diabetic patients with normal hearing and were compared with responses of another group of 20 normal individuals. Eighth nerve transmission till the level of cochlear nucleus was found to be normal in diabetics. The delay in latency of Wave III, IV and V and interpeak latencies (I–III, I–V) were noted to be statistically significant, thus suggesting the presence of central neuropathy in patients with diabetes. No significant sex difference on latency of waves was observed. 相似文献
43.
S. C. Mishra H. Sharma A. Tripathi 《Indian journal of otolaryngology and head and neck surgery》1993,45(1):29-30
A case of veruccous carcinoma of the maxilla extending to alveulus and palate is reported. Treated with radical maxillectomy: there has been no recurrence within one year. The coexistance of submicous fibrosis and veruccous carcinoma is observed and the histological features of the later are highlighted. 相似文献
44.
Louis E. Samuels M.D. Sameer Sharma B.A. Rohinton J. Morris M.D. M.L. Ray Kuretu M.D. Karl E. Grunewald M.D. Michael D. Strong III M.D. Stanley K. Brockman M.D. 《Journal of cardiac surgery》1996,11(2):121-127
A bstract Objectives and Background : The purpose of this study was to document our initial experience with patients 90 years of age and older and to determine whether cardiac surgery is justified in this age group. Cardiac surgery in octogenarians has proven to be a successful and worthwhile procedure. A small group of nonagenarians with severe coronary artery disease (CAD) and aortic valve disease refractory to medical therapy have been considered for surgery. Methods : Fourteen patients aged 90 or more underwent cardiac surgery for symptomatic CAD or aortic valvular disease refractory to medical therapy. Eight patients underwent isolated coronary artery bypass grafting (CABG) and six patients underwent aortic valve replacement (AVR). All patients were in NYHA Class IV preoperatively. Results : Hospital mortality occurred in one patient (7%). Hospital morbidity occurred in 10 patients (71%) and included 7 cardiac, 5 neurological, 1 gastrointestinal, 1 infectious, and 1 pulmonary event. All survivors left the hospital symptomatically improved. The mean length of stay was 26 days. Four CABG patients went on to die at a mean of 2 years and 2 months, and 3 remain alive at a mean of 2 years and 4 months. Three AVR patients expired at a mean of 3 years and 4 months, and 3 remain alive at 4 years and 1 month. Conclusions : Cardiac surgery in carefully selected nonagenarians is justified and can be performed with acceptable results. 相似文献
45.
Mamta Sharma Dorine Berriel-Cass Joseph Baran 《Infection control and hospital epidemiology》2004,25(6):468-471
OBJECTIVE: Surgical-site infection (SSI) is a serious and costly complication following coronary artery bypass graft (CABG). We analyzed surgical factors, microbiology, and complications at a 608-bed community teaching hospital to identify opportunities for prevention. METHODS: All patients undergoing CABG procedures from June 1997 through December 2000 were analyzed. Hospital records and postdischarge surveillance data were reviewed for demographics, surgical information, timing and classification of infection, microbiology, and bacteremic events. RESULTS: Of 3,443 patients undergoing CABG, sternal SSI developed in 122 (3.5%); 71 (58.2%) were classified as superficial SSI and 51 (41.8%) as deep SSI. Surgical antimicrobial prophylaxis was employed in all cases. On average, infection occurred 21.5 days (range, 4 to 315) after CABG. Most cases were diagnosed on readmission (59%); 20 cases (16%) were identified by postdischarge surveillance. Microbiological data were positive in 109 (89.3%), with a single pathogen implicated in most (86.2%). Gram-positive cocci were most frequently recovered (81%); gram-negative bacilli (17%), gram-positive bacilli (1%), and yeast (1%) were less common. Staphylococcus aureus was the most frequently isolated pathogen (49%). Bacteremia was noted in 22 instances (18%). It was significantly associated with deep SSI (P =. 002) and identified only in S. aureus cases. CONCLUSIONS: SSI complicated 3.5% of the procedures. S. aureus was implicated in most of the cases and was significantly associated with deep SSI. It was the only pathogen associated with secondary bacteremia. In addition to standard guidelines, targeted methods against S. aureus should help reduce the overall rate of SSI. 相似文献
46.
47.
Intradural cavernomas are rare vascular lesions of the spinal cord. Four cases of histologically verified cavernomas of the cord are reported, of which two were extramedullary and two were intramedullary in location. Progressive neurological deficit was the presenting feature in three cases while one patient had a rapid evolution of neurological deficits and was found at surgery to have had bled from the extramedullary lesion. All the patients were subjected to surgery and total excision of the cavernomas was carried out in each case. While two patients improved after surgery the other two remained static. The available literature on spinal cord cavernomas is reviewed. 相似文献
48.
49.
B. H. Green J. R. M. Copeland M. E. Dewey V. Sharma I. A. Davidson 《International journal of geriatric psychiatry》1994,9(10):789-795
The Liverpool Continuing Health in the Community Study has followed up 1070 elderly community subjects over 6 years. In the first year 123 subjects had case-level depression. Three years later 49 (39.8%) of the previously depressed were recovered, 33 (26.8%) were depressed, 16 (13%) were not available for interview and 25 (20.3%) were dead. This study looks at factors associated with the 3-year outcome of patients who were depressed at year 0. Two outcome groups that were compared were a recovered depression group and a recurrent/persistent depression group. The factors that were significantly associated with a recurrence of depression (or persistent depression) at year 3 were bereavement of a close figure in the 6 months before interview, loneliness and life dissatisfaction at year 3. A variety of traditional risk factors for depression (including age, marital status, physical ill-health and incapacity) failed to attain significance in predicting recurrent or persistent depression. When combined, both recovered and recurrently depressed groups at year 3 had significantly higher levels of pain and a higher number of serious upsets in the past 6 months and 6 weeks compared to a compared to a control group. The depressed at year 0 were more likely to have entered more dependent forms of accommodation by year 3. 相似文献
50.
Osteoclastoma of the calvarial bone of membranous origin is a rare entity. This paper presents a case of osteoclastoma of the occipital bone and a brief review of literature. 相似文献