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   26531篇
  免费   1288篇
  国内免费   63篇
耳鼻咽喉   393篇
儿科学   700篇
妇产科学   545篇
基础医学   3182篇
口腔科学   310篇
临床医学   2635篇
内科学   5615篇
皮肤病学   542篇
神经病学   2357篇
特种医学   1254篇
外科学   4166篇
综合类   263篇
一般理论   24篇
预防医学   1828篇
眼科学   437篇
药学   1811篇
  1篇
中国医学   28篇
肿瘤学   1791篇
  2024年   173篇
  2023年   329篇
  2022年   566篇
  2021年   1170篇
  2020年   674篇
  2019年   996篇
  2018年   1075篇
  2017年   720篇
  2016年   751篇
  2015年   943篇
  2014年   1195篇
  2013年   1491篇
  2012年   2151篇
  2011年   2207篇
  2010年   1170篇
  2009年   936篇
  2008年   1439篇
  2007年   1450篇
  2006年   1364篇
  2005年   1205篇
  2004年   1047篇
  2003年   896篇
  2002年   809篇
  2001年   258篇
  2000年   181篇
  1999年   206篇
  1998年   154篇
  1997年   111篇
  1996年   115篇
  1995年   89篇
  1994年   69篇
  1993年   64篇
  1992年   126篇
  1991年   122篇
  1990年   115篇
  1989年   124篇
  1988年   92篇
  1987年   105篇
  1986年   89篇
  1985年   95篇
  1984年   76篇
  1983年   55篇
  1982年   55篇
  1981年   61篇
  1980年   44篇
  1979年   55篇
  1978年   48篇
  1973年   52篇
  1972年   53篇
  1970年   41篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.

Background

Valgus knee deformity accounts for only 10% of total knee arthroplasties (TKAs), but is frequently considered the most challenging to manage. This study provides a 10-year follow-up on a previously reported series of severe valgus knees performed using an unconstrained mobile-bearing TKA with a modified technique to validate this technique.

Methods

A consecutive series of 275 predominantly cementless TKAs in 262 patients were performed for severe valgus (≥10°) deformity and prospectively followed to 10 years. Patient-reported outcome measures included the Oxford Knee Score, American Knee Society Score, Bartlett Patellar Score, and the Short Form 12 questionnaire.

Results

Average valgus deformity was reduced from 15.6° to 3.8° (P < .001). At a mean follow-up of 10.4 years (range, 9.5-14.1), 90 (34.4%) patients had died. Of the reviewed survivors, the mean Oxford Knee Score was 27.8 ± 9.8, with an American Knee Society clinical score of 85.6 ± 17.0 and a functional score of 65.1 ± 20.4, with 78% of patients reporting good to excellent results. To date, there has been 1 (0.36%) revision and 13 (4.73%) reoperations. Kaplan-Meier implant survival was 99.6% at 10 years.

Conclusion

Despite its challenging nature, the valgus knee is associated with excellent survivorship and satisfactory long-term results using this modified technique.

Level of Evidence

Level IV.  相似文献   
92.
HSS Journal ® - Rotator cuff tears are a common cause of disability. Some patients with massive and irreparable tears can develop cuff tear arthropathy (CTA), which makes management more...  相似文献   
93.
Background

Perioperative anaemia in relation to surgery is associated with adverse clinical outcomes. In an elective surgical setting, it is possible to optimize patients prior to surgery, often by iron supplementation with correction of anaemia. Possibilities for optimization prior to and during acute surgical procedures are limited. This review investigates whether iron treatment initiated perioperatively improves outcomes in patients undergoing major acute non-cardiac surgery.

Method

This systematic review was performed using PubMed, EMBASE (Ovid) and Scopus to identify current evidence on iron supplementation in acute surgery. Primary outcomes were allogenic blood transfusion (ABT) rate and changes in haemoglobin. Secondary outcomes were postoperative mortality, length of stay (LOS), and postoperative complications. Iron was administered at latest within 24 h after end of surgery.

Results

Of the 5413 studies screened, four randomized controlled trials and nine observational cohort studies were included. Ten studies included patients with hip fractures. A meta-analysis of seven studies showed a risk reduction of transfusion (OR = 0.35 CI 95% (0.20–0.63), p = 0.0004, I2 = 66%). No influence on plasma haemoglobin was found. Postoperative mortality was reduced in the iron therapy group in a meta-analysis of four observational studies (OR 0.50 (CI 95% 0.26–0.96) p = 0.04). No effect was found on LOS, but a reduction in postoperative infection was seen in four studies.

Conclusions

This review examined perioperative iron therapy in acute major non-cardiac surgery. IV iron showed a lower 30-day mortality, a reduction in postoperative infections and a reduction in ABT largely due to the observational studies. The review primarily consisted of small observational studies and does not have the power to formally recommend this practice.

  相似文献   
94.
The purpose of this study was to determine the actual standardized uptake value (SUV) by using the lesion size from computer tomography (CT) scan to correct for resolution and partial volume effects in positron emission tomography (PET) imaging. This retrospective study included 47 patients with lung lesions seen on CT scan whose diagnoses were confirmed by biopsy or by follow up CT scan when the PET result was considered negative for malignancy. Each lesion's FDG uptake was quantified by the SUV using two methods: by measuring the maximum voxel SUV (maxSUV) and by using the lesion's size on CT to calculate the actual SUV (corSUV). Among small lesions (2.0 cm or smaller on CT scan), ten were benign and 17 were malignant. The average maxSUV was 1.43+/-0.77 and 3.02+/-1.74 for benign and malignant lesions respectively. When using an SUV of 2.0 as the cutoff to differentiate benignity and malignancy, the sensitivity, specificity, and accuracy were 65%, 70%, and 67% respectively. When an SUV of 2.5 was used for cutoff, the sensitivity, specificity, and accuracy were 47%, 80%, and 59% respectively. The average corSUV was 1.65+/-1.09 and 5.28+/-2.71 for benign and malignant lesions respectively. Whether an SUV of either 2.0 or 2.5 was used for cutoff, the sensitivity, specificity, and accuracy remained 94%, 70%, and 85% respectively. The only malignant lesion that was falsely considered benign with both methods was a bronchioalveolar carcinoma which did not reveal any elevated uptake of fluorine-18 fluorodeoxyglucose (FDG). Of the large lesions (more than 2.0 cm and less than 6.0 cm), one was benign and 19 were malignant and the corSUV technique did not significantly change the accuracy. It is concluded that measuring the SUV by using the CT size to correct for resolution and partial volume effects offers potential value in differentiating malignant from benign lesions in this population. This approach appears to improve the accuracy of FDG-PET for optimal characterization of small lung nodules.  相似文献   
95.

Background

In April 2010 Sierra Leone launched a nationwide program that provides free health care to all pregnant and lactating women and children under 5 years old. This study evaluates the effect that the free health-care program had on pediatric surgical activities of Connaught Hospital.

Methods

The study period was defined as the 20 months before and after April 27, 2010, the start date of the free health-care program. Data on age, gender, diagnosis, and procedure for patients under 5 years of age and the total number of operations were collected from the Connaught Hospital operating room logbook.

Results

The number of operations on children under 5 increased by 500 %, from 42 to 210 cases. This increase was significantly larger than the 17 % increase of 1,393–1,630 seen with operations for patients 5 years and older (p < 0·01).

Conclusion

The decision by the Sierra Leone President to institute a program of free health care for children under 5 has resulted in an increased number of pediatric surgical cases at Connaught Hospital. Efforts should be undertaken to provide additional supplies and equipment and to develop training programs for surgeons and support staff to care for the children in need of surgical care.  相似文献   
96.
An unusual benign multicentric esophageal granular cell tumor (granular cell myoblastoma) associated with 16 other similar tumors in the skin, vulva, breast, and tongue of 1 patient is described. There was a family history of granular cell tumors in the patient's mother; this has not been previously described. The pathologic findings and controversial histogenesis of granular cell tumors are discussed in an effort to delete the erroneous term "myoblastoma" from the radiologist's vocabulary. Granular cell tumors of the esophagus are also specifically reviewed.  相似文献   
97.
98.
99.
100.
Deep brain stimulation (DBS) is effective for Parkinson’s disease (PD), dystonia, and essential tremor (ET). While motor benefits are well documented, cognitive and psychiatric side effects from the subthalamic nucleus (STN) and globus pallidus interna (GPi) DBS for PD are increasingly recognized. Underlying disease, medications, microlesions, and post-surgical stimulation likely all contribute to non-motor symptoms (NMS).  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