全文获取类型
收费全文 | 3803篇 |
免费 | 273篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 82篇 |
妇产科学 | 98篇 |
基础医学 | 462篇 |
口腔科学 | 111篇 |
临床医学 | 344篇 |
内科学 | 917篇 |
皮肤病学 | 40篇 |
神经病学 | 292篇 |
特种医学 | 266篇 |
外科学 | 427篇 |
综合类 | 61篇 |
一般理论 | 3篇 |
预防医学 | 251篇 |
眼科学 | 87篇 |
药学 | 182篇 |
中国医学 | 18篇 |
肿瘤学 | 425篇 |
出版年
2023年 | 20篇 |
2022年 | 46篇 |
2021年 | 95篇 |
2020年 | 58篇 |
2019年 | 78篇 |
2018年 | 107篇 |
2017年 | 72篇 |
2016年 | 92篇 |
2015年 | 78篇 |
2014年 | 122篇 |
2013年 | 162篇 |
2012年 | 254篇 |
2011年 | 254篇 |
2010年 | 148篇 |
2009年 | 149篇 |
2008年 | 215篇 |
2007年 | 191篇 |
2006年 | 176篇 |
2005年 | 173篇 |
2004年 | 156篇 |
2003年 | 170篇 |
2002年 | 149篇 |
2001年 | 101篇 |
2000年 | 113篇 |
1999年 | 85篇 |
1998年 | 50篇 |
1997年 | 49篇 |
1996年 | 31篇 |
1995年 | 34篇 |
1994年 | 37篇 |
1993年 | 19篇 |
1992年 | 54篇 |
1991年 | 68篇 |
1990年 | 43篇 |
1989年 | 52篇 |
1988年 | 37篇 |
1987年 | 48篇 |
1986年 | 41篇 |
1985年 | 31篇 |
1984年 | 29篇 |
1983年 | 24篇 |
1982年 | 23篇 |
1981年 | 19篇 |
1979年 | 15篇 |
1977年 | 15篇 |
1974年 | 10篇 |
1973年 | 9篇 |
1969年 | 8篇 |
1968年 | 9篇 |
1965年 | 9篇 |
排序方式: 共有4090条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Luis Gajate Ascensión Martín Elena Elías Maria T Tenorio Angélica de Pablo Cristina Carrasco Adolfo Martínez Angel Candela Javier Zamora Fernando Lia?o 《Liver transplantation》2006,12(9):1371-1380
Although renal dysfunction is common after liver transplantation, postoperative renal function after split liver transplantation (SLT) has not been well studied. Renal function immediately after surgery was analyzed retrospectively in 16 patients that received a SLT (SLT group). The results were compared with corresponding data from 31 matched patients that received a full-size liver transplant (FSLT group) during the same period. Serum creatinine (SCr) was measured before surgery, and, after transplantation, daily during the first week and at days 14, 21, and 28. Renal dysfunction (RD) was defined as the requirement for renal replacement therapy (RRT) or a 100% increase in SCr if the basal value had been <1.0 mg/dL or a 50% increase in SCr if the basal value had been >1.0 mg/dL. SCr had to be at least 1.5 mg/dL for a diagnosis of RD to be considered. The classification of RD was: mild, SCr 1.5-2.4 mg/dL; moderate, SCr 2.5-4.0 mg/dL; or severe, SCr >4.0 mg/dL (the requirement for RRT). Both donor and recipient age and cold ischemia time were lower in the SLT group than in the FSLT group (P < 0.05). Length of surgery was longer in the SLT group (P < 0.05). There were no significant differences between groups with respect to Model for End-Stage Liver Disease scores, the need for transfusions, the length of admission to the intensive care unit (ICU), survival rate, individual severity index, or sepsis-related organ failure assessment scores at the time of diagnosing RD. Immunosuppression regimens were similar in both groups. RD developed in 82% of SLT patients, but in only 58% of FSLT patients (P = not significant [NS]). Among SLT patients, RD (23.0% mild, 15.5% moderate, and 61.5% severe) was more severe (P = 0.007) than in FSLT patients (63.1% mild, 15.8% moderate, and 24.1% severe). The requirement for RRT in the SLT group (43.7%) was significantly greater (P < 0.05) than that in the FSLT group (12.9%). This finding may be due to the different incidence of sepsis in the 2 groups (SLT 37.5% vs. FSLT 9.7%; P < 0.05). In conclusion, although the number of patients studied was small, our data suggest a higher incidence of RD and a greater requirement for RRT in patients that receive a split liver graft than in those that receive a full size liver graft. 相似文献
5.
6.
Michelle L. DeOliveira Timothy M. Pawlik Ana L. Gleisner Lia Assumpcaom Gaspar J. Lopes-Filho Michael A. Choti 《Journal of gastrointestinal surgery》2007,11(8):970-976
Survival after resection of colorectal liver metastases has traditionally been associated with clinicopathologic factors.
We sought to investigate whether echogenicity of colorectal liver metastasis as assessed by intraoperative ultrasound (IOUS)
was a prognostic factor after hepatic resection. Prospective data on tumor IOUS appearance were collected in 84 patients who
underwent hepatic resection for colorectal liver metastasis. Images were digitally recorded, blindly reviewed, and scored
for echogenicity (hypo-, iso-, or hyperechoic). The median tumor number was 1 and the median tumor size was 5.0 cm. At the
time of surgery, the IOUS appearance of the colorectal liver metastases were hypoechoic in 35 (41.7%) patients, isoechoic
in 37 (44.0%) patients, and hyperechoic in 12 (14.3%) patients. Traditional clinicopathologic prognostic factors were similarly
distributed among the three echogenicity groups (all p > 0.05). Patients with a hypoechoic lesion had a significantly shorter median survival (30.2 months) compared with patients
who had either an isoechoic (53.2 months) or hyperechoic (42.3 months) lesion (p = 0.005). The 5-year survival after hepatic resection of colorectal liver metastasis was also associated with the echogenic
appearance of the lesion (hypoechoic 14.4 vs isoechoic 37.4 vs hyperechoic 46.2%) (p < 0.05). Intraoperative ultrasound echogenicity should be considered a prognostic factor after hepatic resection of metastatic
colorectal cancer.
This study was presented at the 47th annual meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, CA, USA,
22 May 2006. 相似文献
7.
S Majumdar S C Orphanoudakis A Gmitro M O'Donnell J C Gore 《Magnetic resonance in medicine》1986,3(4):562-574
The accurate estimation of the spin-spin relaxation time T2 is an important goal in magnetic resonance imaging particularly because it can be used for quantitative tissue characterization. The spin-spin relaxation time T2 may be estimated using multiecho pulse sequences, but the accuracy of the estimate is dependent on the fidelity of the spin-echo amplitudes, which may be severely compromised by rf pulse and static field imperfections. In this paper, the effects of static field inhomogeneities are investigated. The propagation of the errors introduced by off-resonance effects are analyzed through computer simulations and analytical solutions of the Bloch equations. A series of experiments performed on a simple tissue phantom using a whole-body imaging system operating at 6.35 MHz corroborates the simulation and analytical results. For accurate measurements of T2 using a whole-body imaging system it is necessary to correct for these inhomogeneities. A correction scheme which would enable a more accurate estimate of T2 is currently under investigation. 相似文献
8.
9.
Whether sphenoidal electrodes should be used in the presurgical evaluation of people with refractory epilepsy has remained controversial. Many studies have been published touting their advantages, or conversely, their lack of benefit. The present paper reviews the evidence supporting the utility of sphenoidal electrodes. In principle, sphenoidal electrodes have an advantage over laterally placed scalp electrodes in detecting inferiorly directed mesial temporal discharges. Published studies demonstrate that sphenoidal electrodes are more sensitive than scalp electrodes and sometimes detect interictal spikes and seizures not seen with scalp electrodes. While the net added yield is relatively low, perhaps 5 to 10%, those patients in whom sphenoidal electrodes provide unique localizing information have much to gain. Sphenoidal electrodes may spare some patients unnecessary intracranial electrode investigation and permit surgery for others. 相似文献
10.
M R Howard J M Hows S M Gore J Barrett M K Brenner J M Goldman E C Gordon-Smith C Poynton H G Prentice J A Whittaker 《Transplantation》1990,49(3):547-553
Retrospectively we analyzed the histocompatibility data and clinical results of bone marrow transplantation in 51 patients who received marrow from unrelated donors (UD) from 1977 to 1987 at one of four UK BMT centers. We compared the results with those obtained in 51 transplants carried out at the same centers using HLA-identical (ID) sibling donors. Of the UD/recipient pairs 32 (63%) were serologically identical for HLA A, B, and DR antigens, and 37% showed varying degrees of mismatch. UD-BMT primary diagnoses were: severe aplastic anemia or Fanconi's anemia (n = 17), acute leukemia (n = 11), chronic myeloid leukemia (n = 21), and other conditions (n = 2). T cell depletion of the graft was associated with a significant improvement in survival in both UD and ID-BMT. Graft failure was more common in recipients of UD than of ID transplants (13 [25%] vs. 5 [10%] P = 0.05) but there was no significant difference in the frequency of acute or chronic graft-versus-host disease. Actuarial survival was superior for recipients of ID transplants (UD vs. ID: 49% vs. 78%, respectively, at 3 months; 32% vs. 63% at one year). Reduced survival for recipients of UD-BMT was confirmed in case control regression analysis (relative risk 3.0, P = 0.01). Nevertheless in patients whose only alternative is a partially mismatched family donor we think that UD-BMT is justified. 相似文献