全文获取类型
收费全文 | 45323篇 |
免费 | 3389篇 |
国内免费 | 168篇 |
专业分类
耳鼻咽喉 | 663篇 |
儿科学 | 1220篇 |
妇产科学 | 785篇 |
基础医学 | 5956篇 |
口腔科学 | 580篇 |
临床医学 | 4638篇 |
内科学 | 9542篇 |
皮肤病学 | 495篇 |
神经病学 | 4358篇 |
特种医学 | 1821篇 |
外科学 | 7562篇 |
综合类 | 837篇 |
现状与发展 | 1篇 |
一般理论 | 40篇 |
预防医学 | 3508篇 |
眼科学 | 589篇 |
药学 | 3115篇 |
中国医学 | 58篇 |
肿瘤学 | 3112篇 |
出版年
2023年 | 240篇 |
2022年 | 206篇 |
2021年 | 1140篇 |
2020年 | 658篇 |
2019年 | 1073篇 |
2018年 | 1301篇 |
2017年 | 872篇 |
2016年 | 1026篇 |
2015年 | 1238篇 |
2014年 | 1631篇 |
2013年 | 2167篇 |
2012年 | 3602篇 |
2011年 | 3666篇 |
2010年 | 2043篇 |
2009年 | 1831篇 |
2008年 | 3051篇 |
2007年 | 3132篇 |
2006年 | 3049篇 |
2005年 | 3087篇 |
2004年 | 2761篇 |
2003年 | 2609篇 |
2002年 | 2365篇 |
2001年 | 408篇 |
2000年 | 282篇 |
1999年 | 383篇 |
1998年 | 503篇 |
1997年 | 441篇 |
1996年 | 364篇 |
1995年 | 342篇 |
1994年 | 295篇 |
1993年 | 270篇 |
1992年 | 228篇 |
1991年 | 198篇 |
1990年 | 180篇 |
1989年 | 178篇 |
1988年 | 172篇 |
1987年 | 150篇 |
1986年 | 142篇 |
1985年 | 143篇 |
1984年 | 139篇 |
1983年 | 122篇 |
1982年 | 148篇 |
1981年 | 149篇 |
1980年 | 106篇 |
1979年 | 74篇 |
1978年 | 73篇 |
1977年 | 74篇 |
1976年 | 64篇 |
1975年 | 55篇 |
1973年 | 57篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Yukihisa Fukuda Savio L-Y Woo John C Loh Eiichi Tsuda Peter Tang Patrick J McMahon Richard E Debski 《Journal of orthopaedic research》2003,21(6):1107-1112
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination. 相似文献
112.
Charles Seydoux Danièle Gillard Berguer Eric Eeckhout Frank Stumpe Michel Hurni Patrick Ruchat Hossein Sadeghi Jean-Jacques Goy 《Transplant international》1996,9(4):433-436
Transplant atherosclerotic coronary disease remains the leading cause of death in heart transplant recipients. We report the first case of coronary stent implantation in a heart graft for epicardial focal stenosis. Due to the lower rate of restenosis after stenting in the native coronary artery, we suggest that coronary stenting be considered an acceptable, first intention therapeutic option instead of angioplasty alone whenever possible. 相似文献
113.
Andreas Nikolis Apostolos Christopoulos Michel Saint-Cyr Carlos Cordoba Louis Guertin Patrick G Harris 《CANADIAN JOURNAL OF PLASTIC SURGERY》2003,11(1):37-40
Complications following free tissue transfer have been well established in the literature. Common and rare causes of free flap failure must be addressed by the treating surgeon when microvascular patency is threatened. With the evolution and prevalence of microsurgery, ‘rare’ causes of free flap failure will become increasingly frequent. A high index of suspicion must be established in patients with multiple failed operative interventions. A case of recurrent free flap failure secondary to heparin-induced thrombocytopenia is presented in a patient with a history of squamous cell carcinoma of the floor of the mouth, and a long-standing history of alcohol and tobacco consumption. 相似文献
114.
Changes in muscle morphology in dialysis patients after 6 months of aerobic exercise training. 总被引:2,自引:1,他引:1
Giorgos K Sakkas Anthony J Sargeant Thomas H Mercer Derek Ball Pelagia Koufaki Christina Karatzaferi Patrick F Naish 《Nephrology, dialysis, transplantation》2003,18(9):1854-1861
BACKGROUND: In the present study we investigated the effect of a 6-month aerobic exercise programme on the morphology of the gastrocnemius muscle of end-stage renal disease (ESRD) patients. METHODS: Twenty-four ESRD patients volunteered to participate in the training programme and underwent muscle biopsy before training. Eighteen patients completed the training programme of whom nine agreed to a post-training biopsy (one woman and eight men, mean age 56 +/- 15 years). Data are presented for the nine subjects who were biopsied before (PRE) and after training (POST) and separately for the 15 subjects for whom we only have a biopsy before training (cross-sectional group). RESULTS: There were no significant differences (P > 0.05) in fibre type distribution or myosin heavy chain (MyHC) expression between the cross-sectional and PRE/POST groups. The mean cross-section fibre area after training (POST) increased by 46% compared with the PRE training status (P < 0.01). The proportion of atrophic fibres decreased significantly after training in type I, IIa and IIx fibre populations (from 51 to 15%, 58 to 21% and 62 to 32%, respectively). Significant differences were also found in capillary contact per fibre (CC/F), with the muscle having 24% (P < 0.05) more CC/F compared with the PRE training status. No significant differences in cytochrome c oxidase concentration were found between the groups. CONCLUSIONS: In conclusion, exercise appeared to be beneficial in renal rehabilitation by correcting the fibre atrophy, increasing the cross-section fibre area and improving the capillarization in the skeletal muscle of renal failure patients. 相似文献
115.
116.
Bruce Becker MD Robert Woolard MD Ted D. Nirenberg PhD P. Allison Minugh PhD Richard Longabaugh EdD Patrick R. Clifford PhD 《Academic emergency medicine》1995,2(9):784-790
Objectives: To determine the incidence of alcohol use in subcritically injured patients presenting to the ED, by using a saliva alcohol test (SAT) at ED triage during the ED initial assessment; to compare the incidence of alcohol use revealed by the SAT with documentation of alcohol use by ED nurses and emergency physicians (EPs) blinded to the SAT results; and to describe the demographics of the SAT-positive, subcritically injured population.
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior. 相似文献
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior. 相似文献
117.
Paul Devakar Yesudian MD Srivilliputtur G.S. Krishnan MBBS Muriugaiya Jayaraman MD Vanakampadi R. Janaki MD Patrick Yesudian FRCP 《International journal of dermatology》1997,36(3):194-196
Background Pemphigus is a group of vesiculobullous disorders in which the blisters usually heal with hyper- or hypopigmentation. The appearance of acanthomata at sites of previous blisters has been noted in some cases. Methods All cases of pemphigus admitted to the Madras Medical College hospitals during a 2-year period from March 1993 to March 1995 were taken into the study and screened for the presence of acanthomata. Results Fifty-two cases of pemphigus were identified, 47 of pemphigus vulgaris and five of pemphigus foliaceus; and of these 13 developed acanthomata when the blisters healed. Ten of these cases were of pemphigus vulgaris and three were of pemphigus foliaceus; biopsy of these lesions showed hyperkeratosis, acanthosis, papillomatosis, and intraepidermal clefting. Immunofluorescence carried out in two of these acanthomata also showed intercellular fluorescence. Conclusions The occurrence of acanthomata in healed lesions of pemphigus is not uncommon; because histopathologic and immunofluorescence evidence of disease activity is present, cases of this sort require careful follow-up. 相似文献
118.
119.
Nadia Sdiqui Khalil Arar Patrick Midoux Roger Mayer Michel Monsigny Annie-Claude Roche 《Drug delivery》1995,2(1):63-72
The Ha-ras oncogene promotes cell proliferation. Antisense oligonucleotides complementary to the ras gene sequence encompassing a mutated codon 12 selectively induce a cell proliferation inhibition. However, the concentration required to reach an effective inhibition is high due to the low efficiency of the oligonucleotide crossing through cell membranes, leading to a low concentration in the cytosol and/or the nucleoplasm. In the present paper, we show that anti-ras oligonucleotides linked to a glycosylated carrier, serum albumin bearing mannose 6-phosphate residues, are more efficient than free oligonucleotides or oligonucleotides bound to an unglycosylated carrier at inhibiting proliferation of a human tumor mammary cell line expressing the mutated Ha-ras. Using fluorescein-labeled neoglycoproteins and fluorescein-labeled oligonucleotides bound to neoglycoproteins, flow cytometry and confocal microscopy revealed that (i) these tumor cells express a membrane lectin specific for mannose 6-phosphate-bearing proteins, (ii) the membrane lectin actively mediates the uptake of macromolecules substituted with mannose 6-phosphate, and (iii) the fluorescein-labeled oligonucleotides bound to the neoglycoprotein accumulate in intracellular vesicles. Furthermore, with antisense oligonucleotides carried by the neoglycoproteins, the concentration required to inhibit cell proliferation is lower than that of the carrier-free antisense oligonucleotides. 相似文献
120.