全文获取类型
收费全文 | 66638篇 |
免费 | 4789篇 |
国内免费 | 125篇 |
专业分类
耳鼻咽喉 | 963篇 |
儿科学 | 1728篇 |
妇产科学 | 1629篇 |
基础医学 | 8990篇 |
口腔科学 | 1497篇 |
临床医学 | 7678篇 |
内科学 | 12453篇 |
皮肤病学 | 1062篇 |
神经病学 | 5469篇 |
特种医学 | 2707篇 |
外国民族医学 | 1篇 |
外科学 | 8926篇 |
综合类 | 1075篇 |
现状与发展 | 1篇 |
一般理论 | 38篇 |
预防医学 | 6946篇 |
眼科学 | 1584篇 |
药学 | 4752篇 |
5篇 | |
中国医学 | 79篇 |
肿瘤学 | 3969篇 |
出版年
2022年 | 481篇 |
2021年 | 1118篇 |
2020年 | 662篇 |
2019年 | 1084篇 |
2018年 | 1260篇 |
2017年 | 975篇 |
2016年 | 1011篇 |
2015年 | 1143篇 |
2014年 | 1592篇 |
2013年 | 2376篇 |
2012年 | 3459篇 |
2011年 | 3608篇 |
2010年 | 1944篇 |
2009年 | 1709篇 |
2008年 | 3028篇 |
2007年 | 3288篇 |
2006年 | 3232篇 |
2005年 | 3203篇 |
2004年 | 3044篇 |
2003年 | 2730篇 |
2002年 | 2628篇 |
2001年 | 1754篇 |
2000年 | 1838篇 |
1999年 | 1614篇 |
1998年 | 846篇 |
1997年 | 645篇 |
1996年 | 631篇 |
1995年 | 645篇 |
1994年 | 549篇 |
1993年 | 536篇 |
1992年 | 1348篇 |
1991年 | 1237篇 |
1990年 | 1198篇 |
1989年 | 1133篇 |
1988年 | 1041篇 |
1987年 | 1053篇 |
1986年 | 972篇 |
1985年 | 974篇 |
1984年 | 792篇 |
1983年 | 680篇 |
1982年 | 519篇 |
1981年 | 481篇 |
1980年 | 469篇 |
1979年 | 712篇 |
1978年 | 569篇 |
1977年 | 470篇 |
1974年 | 480篇 |
1973年 | 458篇 |
1972年 | 478篇 |
1971年 | 437篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Jonathan Cook Neil Prose Mitchell Heflin 《Dermatologic surgery》2003,29(9):1994; author reply 1994-1994; author reply 1995
62.
R J Landreneau S R Hazelrigg P F Ferson J A Johnson W Nawarawong T M Boley J J Curtis C M Bowers D B Herlan R D Dowling 《The Annals of thoracic surgery》1992,54(3):415-9; discussion 419-20
Advances in endoscopic surgical equipment and laser technology have expanded the role of thoracoscopy to include thoracoscopic pulmonary resection. Eighty-five thoracoscopic pulmonary resections were performed on 61 consecutive patients with small lesions (less than 3 cm) in the outer third of the lung. Patients with preoperative histologic evidence of bronchogenic carcinoma were excluded unless there was impairment of cardiopulmonary function, advanced age, or concomitant extrathoracic malignancy. These thoracoscopic pulmonary resections were accomplished with the neodymium:yttrium-aluminum garnet laser (31), endoscopic stapler (29), or both (25). The mean diameter of the lesions was 1.3 cm (range, 0.4 to 2.7 cm). There has been one late death (38th postoperative day) unrelated to the operation. Morbidity consisted of postoperative atelectasis (2), pneumonia (2), bleeding requiring transfusion (1), and bronchopleural fistula of greater than 7 days duration (3). There were no wound problems. The mean period of chest tube drainage was 3.3 +/- 3.0 days. Mean postoperative stay was 5.7 +/- 4.9 days. The pathologic diagnosis was benign disease in 28 patients (interstitial fibrosis/pneumonitis, 15; radiation fibrosis, 1; sclerosing hemangioma, 1; rheumatoid nodules, 1; granuloma, 2; nocardia, 1; infarct, 1; hamartoma, 4; scar, 1; cytomegalovirus pneumonia, 1), metastatic malignancy in 20 patients, and bronchogenic carcinoma in 13 patients. Five patients found at thoracoscopic pulmonary resection to have bronchogenic cancer had adequate pulmonary function and therefore underwent formal segmentectomy (3) or lobectomy (2). Thoracoscopic pulmonary resection was the only operation performed on patients with benign disease, patients with metastatic lesions, and selected patients with limited stage bronchogenic carcinoma at increased risk for thoracotomy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
63.
64.
Janice C Probst Sarah B Laditka Jong-Yi Wang Andrew O Johnson 《BMC health services research》2007,7(1):40
Background
Travel burden is a key element in conceptualizing geographic access to health care. Prior research has shown that both rural and minority populations bear disproportionate travel burdens. However, many studies are limited to specific types of patient or specific locales. The purpose of our study was to quantify geographic and race-based differences in distance traveled and time spent in travel for medical/dental care using representative national data. 相似文献65.
We examined the correlates of self-reported lifetime use of alcohol, marijuana, amphetamines, and cocaine within a sample of almost 7,000 high school sophomores in Arizona and Utah. Correlates of drug use (including parental attachment, religious attachment, educational attachment, conventional values, and drug-using friends) showed very similar patterns by gender, with some interesting differences by location. Drug-using friends are by far the best predictor of drug use for both males and females in Arizona and Utah. 相似文献
66.
Tuberculosis of the pancreas: a case report 总被引:2,自引:0,他引:2
A 73-year-old female died of adult respiratory distress syndrome (ARDS) and multiple organ system failure (MOSF) after a routine cholecystectomy for acute cholecystitis. An autopsy revealed disseminated tuberculosis with a tuberculous abscess of the pancreas. 相似文献
67.
The appropriate use of prophylactic antimicrobial therapy in patients undergoing major contaminated surgery is an important issue for the head and neck surgeon. A series of five sequential, prospective, randomized, double-blind clinical trials of antibiotics for patients undergoing major contaminated oncologic head and neck surgery are reviewed and summarized. The information generated from the study of these 547 patients indicates that a number of drugs or drug combinations have similar efficacy when employed in adequate dosage. The bacteriologic spectrum of the prophylactic drug should include oral microflora, especially anaerobic bacteria. The administration of antibiotics effective against gram-negative aerobic bacteria may be unnecessary. Perioperative antibiotic administration should be initiated prior to surgery. To date, no evidence exists to support prolonged administration of antibiotics beyond the first 24 hours following surgery. 相似文献
68.
69.
Role of group II and group III metabotropic glutamate receptors in spinal cord injury. 总被引:4,自引:0,他引:4
Spinal cord injury (SCI) produces an increase in extracellular excitatory amino acid (EAA) concentrations that results in glutamate receptor-mediated excitotoxic events. An important class of these receptors is the metabotropic glutamate receptors (mGluRs). mGluRs can activate a number of intracellular pathways that increase neuronal excitability and modulate neurotransmission. Group I mGluRs are known to modulate EAA release and the development of chronic central pain (CCP) following SCI; however, the role of group II and III mGluRs remains unclear. To begin evaluating group II and III mGluRs in SCI, we administered the specific agonists for group II, APDC, or group III, L-AP4, by interspinal injection immediately following SCI. Contusion injury was produced at spinal segment T10 with a New York University impactor (12.5-mm drop, 10-g rod 2 mm in diameter) in 30 adult male Sprague-Dawley rats (175-200 g). Evoked and spontaneous behavioral measures of CCP, locomotor recovery, changes in mGluR expression, and amount of spared tissue were examined. Neither APDC nor L-AP4 affected locomotor recovery or the development of thermal hyperalgesia; however, L-AP4 and APDC attenuated changes in mechanical thresholds and changes in exploratory behavior indicative of CCP. APDC- and L-AP4-treated groups had higher expression levels of mGluR2/3 at the epicenter of injury on post contusion day 28; however, there was no difference in the amount of spared tissue between treatment groups. These results demonstrate that treatment with agonists to group II and III mGluRs following SCI affects mechanical responses, exploratory behavior, and mGluR2/3 expression without affecting the amount of tissue spared, suggesting that the level of mGluR expression after SCI may modulate nociceptive responses. 相似文献
70.
A case is reported of an auto-immune haemolytic anaemia caused by IgM anti-D. This antibody, although active at 37 degrees C, gave stronger reactions at lower temperatures and appeared to activate complement. The auto-immune haemolytic anaemia was probably secondary to a non-Hodgkins lymphoma. 相似文献