全文获取类型
收费全文 | 5120篇 |
免费 | 373篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 128篇 |
妇产科学 | 108篇 |
基础医学 | 600篇 |
口腔科学 | 135篇 |
临床医学 | 1036篇 |
内科学 | 803篇 |
皮肤病学 | 23篇 |
神经病学 | 350篇 |
特种医学 | 371篇 |
外科学 | 592篇 |
综合类 | 111篇 |
一般理论 | 2篇 |
预防医学 | 503篇 |
眼科学 | 27篇 |
药学 | 348篇 |
中国医学 | 7篇 |
肿瘤学 | 364篇 |
出版年
2022年 | 35篇 |
2021年 | 71篇 |
2020年 | 50篇 |
2019年 | 96篇 |
2018年 | 110篇 |
2017年 | 78篇 |
2016年 | 89篇 |
2015年 | 93篇 |
2014年 | 127篇 |
2013年 | 280篇 |
2012年 | 234篇 |
2011年 | 226篇 |
2010年 | 147篇 |
2009年 | 152篇 |
2008年 | 225篇 |
2007年 | 250篇 |
2006年 | 211篇 |
2005年 | 179篇 |
2004年 | 172篇 |
2003年 | 153篇 |
2002年 | 156篇 |
2001年 | 158篇 |
2000年 | 139篇 |
1999年 | 146篇 |
1998年 | 136篇 |
1997年 | 112篇 |
1996年 | 122篇 |
1995年 | 97篇 |
1994年 | 86篇 |
1993年 | 90篇 |
1992年 | 112篇 |
1991年 | 96篇 |
1990年 | 91篇 |
1989年 | 90篇 |
1988年 | 100篇 |
1987年 | 63篇 |
1986年 | 85篇 |
1985年 | 55篇 |
1984年 | 55篇 |
1983年 | 35篇 |
1982年 | 30篇 |
1980年 | 30篇 |
1979年 | 37篇 |
1978年 | 31篇 |
1976年 | 34篇 |
1975年 | 35篇 |
1974年 | 32篇 |
1973年 | 32篇 |
1972年 | 32篇 |
1971年 | 28篇 |
排序方式: 共有5542条查询结果,搜索用时 15 毫秒
61.
The material properties of the bovine acetabular labrum. 总被引:2,自引:0,他引:2
The compressive and tensile material properties of the bovine acetabular labrum were measured. Confined compression testing was used to determine the aggregate compressive modulus and the permeability of the labrum. The compressive modulus of the labrum (0.157 +/- 0.057 MPa) is comparable to that of the morphologically similar meniscus, and approximately one-quarter to one-half that of the adjoining acetabular cartilage. The permeability of the labrum (4.98 +/- 3.43 x 10(-16) m4/N s) was lower than that of the meniscus and cartilage. With a significantly higher resistance to interstitial fluid flow across the acetabular rim than along the rim. Specimens from the posterior and superior regions of the labrum were tested to failure in uniaxial tension. The maximum stress at failure (11.9 +/- 6.1 MPa), maximum strain at failure (26.5 +/- 7.6%) and tangent modulus (74.7 +/- 44.3 MPa) were similar to those reported for the bovine meniscus, and to other tissues composed of highly oriented collagen fiber bundles. In tension, the labrum is much stiffer (10-15 x) than the adjoining articular cartilage, and the posterior region of the labrum is significantly stiffer (45%) than the superior region. The labrum's low permeability may contribute to sealing of the hip joint. The high circumferential tensile stiffness of the labrum, together with its ring structure, reinforce the acetabular rim and may contribute to joint stability. 相似文献
62.
Jay R Shapiro Caressa Lietman Monica Grover James T Lu Sandesh CS Nagamani Brian C Dawson Dustin M Baldridge Matthew N Bainbridge Dan H Cohn Maria Blazo Timothy T Roberts Feng‐Shu Brennen Yimei Wu Richard A Gibbs Pamela Melvin Philippe M Campeau Brendan H Lee 《Journal of bone and mineral research》2013,28(7):1523-1530
63.
We have previously reported the time trends, design and interventions in randomised controlled trials (RCTs) in cystic fibrosis (CF) from 1961 through 1997 [Cheng K, Smyth RL, Motley J, O'Hea U, Ashby D, Randomised controlled trials in cystic fibrosis (1966-1997) categorized by time, design, and intervention. Pediatr Pulmonol 2000, 29:1-7.]. We maintain an ongoing register of all RCTs and controlled clinical trials (CCTs) in CF and have noted that in the five years since 1997 there has been a 48% increase in published trials. We aimed to assess whether this increase has been associated with an improvement in design quality. All RCTs and CCTs from 1961-2002 were assessed. Two epochs were then compared, 1961-1997 and 1998-2002. For each trial we recorded the design, participant numbers and the intervention studied. 261 trials in 1998-2002 were compared with 544 trials in 1961-1997. Comparing the two epochs a similar proportion of trials were parallel, double-blind and placebo controlled; also the median number of participants was similar. In the later epoch 25% of trials were multicentre, compared with 11% previously. Whilst this recent increase in clinical trials in CF is welcome, this has not been associated with improvements in quality. The trend for an increasing proportion of trials to be multicentre is encouraging. There are however, still deficiencies in the design of clinical trials in CF. 相似文献
64.
65.
Allogeneic marrow transplantation in patients with chronic myeloid leukemia in the chronic phase: a randomized trial of two irradiation regimens 总被引:1,自引:5,他引:1
R A Clift C D Buckner F R Appelbaum E Bryant S I Bearman F B Petersen L D Fisher C Anasetti P Beatty W I Bensinger 《Blood》1991,77(8):1660-1665
A randomized trial was performed to compare two regimens of total body irradiation in patients with chronic myeloid leukemia treated by allogeneic marrow transplantation while in the chronic phase. All patients received cyclophosphamide 120 mg/kg followed by total body irradiation and marrow from HLA-identical siblings. Cyclosporine and methotrexate were used for prophylaxis against acute graft-versus-host disease. Fifty-seven patients were randomized to receive 2.0 Gy fractions of irradiation daily for 6 days and 59 were randomized to receive 2.25 Gy fractions daily for 7 days. The probabilities of relapse at 4 years were 0.25 for the 12.0 Gy group and 0.00 for the 15.75 Gy group (P = .008). The actuarial probabilities of survival and relapse-free survival at 4 years were 0.60 and 0.58 among the patients who received 12.0 Gy compared with 0.66 and 0.66 for those who received 15.75 Gy. The 4-year probabilities of transplant-related mortality were 0.24 and 0.34 respectively (P = .13) while the probability of moderate to severe acute graft-versus-host disease was 0.33 for the 12.0 Gy group and 0.44 for the 15.75 Gy group (P = .15). The lower relapse probability in the patients receiving the higher dose of total body irradiation did not result in improved survival because mortality from causes other than relapse was increased. 相似文献
66.
67.
The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases. Questions or suggestions for topics should be addressed to Dominic A. Solimando, Jr, President, Oncology Pharmacy Services, Inc., 4201 Wilson Blvd #110-545, Arlington, VA 22203, e-mail: ten.tsacmoc@cvSxRcnO; or J. Aubrey Waddell, Professor, University of Tennessee College of Pharmacy; Oncology Pharmacist, Pharmacy Department, Blount Memorial Hospital, 907 E. Lamar Alexander Parkway, Maryville, TN 37804, e-mail: ten.retrahc@ruofddaw.Regimen name: VMPOrigin of name: VMP is an acronym for the 3 drugs (bortezomib [Velcade], melphalan, and prednisone) in the regimen. 相似文献
68.
McGinnis Kathleen A. Tate Janet P. Bryant Kendall J. Justice Amy C. O’Connor Patrick G. Rodriguez-Barradas Maria C. Crystal Stephen Cutter Christopher J. Hansen Nathan B. Maisto Stephen A. Marconi Vincent C. Williams Emily C. Cook Robert L. Gordon Adam J. Gordon Kirsha S. Eyawo Oghenowede Edelman E. Jennifer Fiellin David A. 《AIDS and behavior》2022,26(3):786-794
AIDS and Behavior - The timeline followback (TLFB) takes more resources to collect than the Alcohol Use Disorder Identification Test (AUDIT-C). We assessed agreement of TLFB and AUDIT-C with the... 相似文献
69.
Dr. Robert H. Thorlakson M.D.; F.R.C.S. F.R.C.S.C. F.A.CS. 《Diseases of the colon and rectum》1986,29(9):591-593
A set of double-angled needle holders and long, angled tissue forceps have been designed and presented for use in surgery
of the abdomen. The problems of passage and control of curved needles in all directions is well recognized. The marriage of
design and presentation addresses the mechanical and anatomic needs of surgeons in the pelvis, subdiaphragmatic area, and
in large and obese patients. Multiple variables in use provided by these instruments, particularly when used together, enhance
surgical control at problem sites. 相似文献
70.
Bryant Lin Paul J. Wang Srijoy Mahapatra Munther Homoud Mark Link N.A. Mark Estes Amin Al‐Ahmad 《Annals of noninvasive electrocardiology》2005,10(2):142-145
Background: Morphologic identification of ectopic P‐waves from surface ECGs can be challenging, particularly when the P‐wave is buried in the QRST wave complex. Because ECGs are often available on paper and not digitally, we developed a method of subtracting the T‐wave from the buried P‐wave complex on paper ECGs. Methods: To validate our system, an atrial extrastimulus was introduced during and following the T‐wave. The ECGs were scanned and then transformed from an image format to a digital format. A computer algorithm digitally subtracted a QRST with no buried P‐wave from one with a buried P‐wave, thus resulting in an extracted P‐wave. The extracted P‐waves were compared to the nonburied P‐wave by determining correlation coefficients and by visual grading by two independent reviewers. Results: Visual grading comparing the buried P‐wave with the exposed paced P‐wave was 94%. The median correlation coefficient was 85%. Conclusions: An ectopic atrial P‐wave obscured by a coincident QRST wave complex can be accurately derived from printed ECG using this PC‐based system. Addition of this technique to the existing methods may aid in the localization and ablation of ectopic atrial foci. 相似文献