全文获取类型
收费全文 | 8574篇 |
免费 | 1440篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 236篇 |
儿科学 | 229篇 |
妇产科学 | 233篇 |
基础医学 | 760篇 |
口腔科学 | 233篇 |
临床医学 | 1579篇 |
内科学 | 1833篇 |
皮肤病学 | 156篇 |
神经病学 | 586篇 |
特种医学 | 297篇 |
外科学 | 1552篇 |
综合类 | 112篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 871篇 |
眼科学 | 211篇 |
药学 | 305篇 |
中国医学 | 33篇 |
肿瘤学 | 851篇 |
出版年
2024年 | 47篇 |
2023年 | 299篇 |
2022年 | 145篇 |
2021年 | 301篇 |
2020年 | 355篇 |
2019年 | 238篇 |
2018年 | 404篇 |
2017年 | 360篇 |
2016年 | 437篇 |
2015年 | 441篇 |
2014年 | 605篇 |
2013年 | 651篇 |
2012年 | 556篇 |
2011年 | 575篇 |
2010年 | 428篇 |
2009年 | 510篇 |
2008年 | 450篇 |
2007年 | 425篇 |
2006年 | 431篇 |
2005年 | 398篇 |
2004年 | 342篇 |
2003年 | 277篇 |
2002年 | 241篇 |
2001年 | 179篇 |
2000年 | 161篇 |
1999年 | 136篇 |
1998年 | 82篇 |
1997年 | 83篇 |
1996年 | 50篇 |
1995年 | 49篇 |
1994年 | 29篇 |
1993年 | 21篇 |
1992年 | 52篇 |
1991年 | 34篇 |
1990年 | 43篇 |
1989年 | 39篇 |
1988年 | 46篇 |
1987年 | 29篇 |
1986年 | 36篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 13篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1977年 | 4篇 |
1975年 | 3篇 |
1970年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
74.
75.
Objective : This study evaluated whether a significant reduction in unnecessary appendectomies is possible by performing diagnostic laparoscopy before appendectomy in female patients of child-bearing age, leaving behind the normal-looking appendix. Materials and methods : Sixty-one consecutive female patients between the ages of 15 and 45 years with clinical diagnosis of acute appendicitis were studied prospectively. Diagnostic laparoscopy was performed to detect whether the appendix was inflamed. The appendix was then removed and the result of laparoscopic diagnosis was matched with histological diagnosis. Results : Ten out of the 42 laparoscopically diagnosed appendicitis cases had normal appendices on histological examination. Six out of the 19 laparoscopically diagnosed normal appendices had histological evidence of appendicitis. The sensitivity of laparoscopy was 84% and the specificity was 56.5%. Conclusions : Discrepancies existed between laparoscopic appearance and histological examination in acute appendicitis. The appendices of all those with clinically suspected appendicitis should be removed and sent for histological confirmation. 相似文献
76.
Organ injuries associated with femoral fractures: implications for severity of injury in motor vehicle collisions 总被引:3,自引:0,他引:3
OBJECTIVE: To determine if motor vehicle collisions (MVCs) resulting in femoral fractures were associated with a different injury severity and pattern of injury compared with crashes in which victims did not sustain femoral fractures. METHODS: Retrospective review of seriously injured motor vehicle occupants admitted to a regional trauma unit (Hamilton General Hospital) during a 69-month period (April 1991 to December 1996) for whom detailed crash details were known. RESULTS: Data for 733 motor vehicle occupants with Injury Severity Scores greater than 12 were available; 112 occupants (15.3%) sustained femoral fractures, and 621 occupants (84.7%) did not sustain femoral fractures. Victims with femoral fractures had a significantly higher mean Injury Severity Score (29.4 compared with 25.3 for non-femoral fracture group; p<0.001). The femoral fracture group had a higher incidence of bowel (p<0.012) and hemopneumothorax (p<0.02) injuries as well as an increased incidence of upper and lower extremity (p<0.001) and pelvic (p<0.05) fractures. CONCLUSION: The presence of a femoral fracture is strongly associated with the pattern and severity of injuries sustained by occupants in MVCs. A high index of suspicion is warranted in identifying associated organ injuries in MVC victims with concomitant femoral fractures. 相似文献
77.
Objectives : The study was undertaken to assess the safety and efficacy of sequential intravenous and oral ciprofloxacin in the treatment of moderate-to-severe urinary tract infections (UTI), and to identify risk factors for acquiring UTI caused by ciprofloxacin-resistant organisms. Materials and Methods : Using a prospective, open, single-centre study design, hospitalized patients with a clinical diagnosis of moderately severe UTI were enrolled. After a minimum of 3 days of intravenous ciprofloxacin, patients were switched to oral therapy. Assessment for response and analysis of risk factors were performed at the end of therapy. Results : Between December 1996 and November 1997, a total of 66 patients met the criteria for efficacy evaluation. Among the 55 patients with ciprofloxacin-sensitive organisms, 51 patients (93%) were cured. Persisting infection was noted in three patients (5%) and one patient (2%) was re-infected with a ciprofloxacin-resistant organism. Of the organisms isolated, 14 (19%) were resistant to ciprofloxacin. The presence of prostatic obstruction (odds ratio 6.02, 95% confidence interval (CI) 1.28–28.30, P = 0.02) and recurrent UTI (odds ratio 8.63, 95% CI 1.81–41.17, P = 0.007) were independently associated with infections caused by ciprofloxacin-resistant organisms. Adverse events were reported in 5 patients (8%) but no premature discontinuation or mortality was documented. Conclusion : Sequential therapy with oral therapy after initial parenteral ciprofloxacin is safe and effective in the management of moderate-to-severe UTI in appropriately selected patients. 相似文献
78.
X. L. Tang L. Qin A. W. Kwok T. Y. Zhu E. W. Kun V. W. Hung J. F. Griffith P. C. Leung E. K. Li L.-S. Tam 《Osteoporosis international》2013,24(6):1817-1826
Summary
Compared to controls, HR-pQCT at distal radius of SLE patients on chronic glucocorticoid (SLE/GC) revealed reduced bone area, vBMD, deteriorated microarchitecture, and unevenly distributed stresses limited to cortical bone. Despite similar trabecular quality, whole bone strength decreased in patients. These alterations may partly explain high fracture rates in SLE/GC.Introduction
To assess bone geometric, densitometric, microarchitectural, and biomechanical properties in patients with systemic lupus erythematosus (SLE) on long-term glucocorticoid (GC) (SLE/GC) as compared with healthy controls.Methods
A total of 180 female SLE patients and 180 healthy controls were in this cross-sectional study to assess areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) and microfinite element analysis (μFEA) was performed at distal radius.Results
In addition to significantly lower aBMD at femoral neck, total hip and lumbar spine, cortical area, average volumetric BMD (vBMD) and cortical vBMD also significantly reduced by 5.3, 5.7, to 1.9 % in SLE patients, respectively. Deteriorations of cortical microarchitecture were pronounced in patients, with 6.3 % reduction in cortical thickness and 13.6 % higher in cortical porosity. Local stresses were more unevenly distributed through cortical bone in patients. SLE/GC patients had decreased whole bone stiffness, estimated failure load, and apparent modulus. Parameters related to trabecular bone density and microarchitecture were comparable between patients and controls.Conclusion
In SLE/GC patients, despite a reduction in bone area, vBMD and deteriorated microarchitecture and unevenly distributed stresses limited to the cortical compartment, whole bone strength decreased. HR-pQCT and μFEA were promising in elucidating the potential underlying pathophysiology of bone loss and propensity to fracture in SLE/GC and provide us additional information about alterations of bone quality which might better predict fracture risk beyond aBMD in SLE/GC. 相似文献79.
Anthony Yuen Bun Teoh Philip Wai Yan Chiu So Fei Hon Tony Wing Chung Mak Enders Kwok Wai Ng James Yun Wong Lau 《Surgical endoscopy》2013,27(4):1422-1427
Background
Endoscopic submucosal dissection (ESD) is a technically demanding procedure, and exposure of the submucosa depends on the action of gravity and submucosal injection. The aim of the study was to investigate the effectiveness of the Endolifter® as a traction device for enhancing submucosal visualization during ESD.Methods
This was a prospective ex vivo comparative study conducted between September 2010 and March 2011 in the Prince of Wales Hospital. Consecutive ESDs were performed by four experienced endoscopists in an ex vivo ESD model with or without the Endolifter®. The Endolifter® allows simultaneous grasping, retracting and lifting of the mucosa during ESD, resulting in exposure of the submucosa. Each of the procedures were recorded and reviewed later by two independent assessors. The outcome measures included the proportion of time that the submucosa was visualized during the procedures (SM ratio), procedural times, perforation rates, amount of submucosal injections, and the difficulty of the procedure.Results
Forty-eight gastric ESD procedures were performed on the model. The SM ratio was higher in the Endolifter® group (P = 0.007), particularly for lesions located at the antrum (P < 0.001). The time required for submucosal dissection and the total procedural time were also less in the Endolifter® group. The endoscopists rated the ESD procedures in the Endolifter® group as less difficult (P = 0.033).Conclusions
The Endolifter® improved submucosal visualization during gastric ESD and reduces the difficulty of performing the procedures. The device may improve the ease of performing ESD in low-volume centers or large mucosal lesions. 相似文献80.
Preoperative ketamine improves postoperative analgesia after gynecologic laparoscopic surgery 总被引:18,自引:0,他引:18
In this study, we evaluated the preemptive effect of a small dose of ketamine on postoperative wound pain. In a randomized, double-blinded, controlled trial, we compared the analgesic requirement in patients receiving preincision ketamine with ketamine after skin closure or placebo after gynecologic laparoscopic surgery. One-hundred-thirty-five patients were randomly assigned to receive preincision or postoperative ketamine 0.15 mg/kg or saline IV. Anesthetic technique was standardized. Patients were interviewed regularly up to 4 wk after surgery. Pain score, morphine consumption, side effects, and quality of recovery score were recorded. Patients receiving preincision ketamine had a lower pain score in the first 6 h after operation compared with the postoperative (P = 0.001) or placebo groups (P < 0.001). The mean (95% confidence intervals) time to first request for analgesia in the preincision group, 1.8 h (1.4-2.1), was longer than the postoperative group, 1.2 h (0.9-1.5; P < 0.001), or the placebo group, 0.7 h (0.4-0.9; P < 0.001). The mean +/- SD morphine consumption in the preincision group, 1.5 +/- 2.0 mg, was less than that in the postoperative group, 2.9 +/- 3.1 mg (P = 0.04) and the placebo group, 3.4 +/- 2.7 mg (P = 0.003). There was no significant difference among groups with respect to hemodynamic variables or side effects. No patient complained of hallucinations or nightmares. We conclude that a small dose of ketamine is not only safe, but it also provides preemptive analgesia in patients undergoing gynecologic laparoscopic surgery. IMPLICATIONS: In women undergoing laparoscopic gynecologic surgery, a small preoperative dose of ketamine (0.15 mg/kg) produced preemptive analgesia. There were no significant hemodynamic and psychological side effects with this dose. 相似文献