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   1463篇
  免费   77篇
  国内免费   4篇
耳鼻咽喉   18篇
儿科学   73篇
妇产科学   31篇
基础医学   165篇
口腔科学   50篇
临床医学   113篇
内科学   314篇
皮肤病学   25篇
神经病学   35篇
特种医学   420篇
外科学   91篇
综合类   40篇
预防医学   29篇
眼科学   13篇
药学   69篇
  1篇
中国医学   6篇
肿瘤学   51篇
  2023年   7篇
  2022年   17篇
  2021年   11篇
  2020年   12篇
  2019年   13篇
  2018年   18篇
  2017年   17篇
  2016年   14篇
  2015年   19篇
  2014年   34篇
  2013年   39篇
  2012年   25篇
  2011年   26篇
  2010年   37篇
  2009年   54篇
  2008年   22篇
  2007年   38篇
  2006年   31篇
  2005年   26篇
  2004年   19篇
  2003年   18篇
  2002年   11篇
  2001年   17篇
  2000年   10篇
  1999年   18篇
  1998年   80篇
  1997年   79篇
  1996年   79篇
  1995年   65篇
  1994年   39篇
  1993年   58篇
  1992年   9篇
  1991年   12篇
  1990年   26篇
  1989年   63篇
  1988年   43篇
  1987年   51篇
  1986年   55篇
  1985年   68篇
  1984年   35篇
  1983年   29篇
  1982年   29篇
  1981年   31篇
  1980年   37篇
  1979年   5篇
  1978年   18篇
  1977年   23篇
  1976年   21篇
  1975年   20篇
  1970年   3篇
排序方式: 共有1544条查询结果,搜索用时 15 毫秒
991.
992.
Archives of Pharmacal Research - Atorvastatin is a 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor used in the treatment of atherosclerosis and dyslipidemia. Studies have evaluated the...  相似文献   
993.
994.
Several plastic materials used in blood storage were evaluated for their ability to transmit ultraviolet B (UVB) light. A plastic bag manufactured from sheets of transparent Teflon efficiently (78-86%) transmitted UVB light and was employed in subsequent functional studies of lymphocytes and platelets exposed to UVB light while contained in these bags. In vitro experiments showed a UVB dose-dependent abrogation of lymphocyte responder and stimulator functions, with concurrent preservation of platelet aggregation responses. In a phase I pilot study, UVB-treated platelet concentrates were administered to four bone marrow transplant recipients. Adverse effects attributable to the transfusions were not observed, and patients showed clinically effective transfusion responses. No patient developed lymphocytotoxic HLA or platelet antibodies. These studies suggest that platelets can be effectively irradiated with UVB light in a closed system. However, numerous variables, including container material, volume and composition of contents, steady exposure versus agitation, and exact UV wavelength, must be considered.  相似文献   
995.
996.
997.
998.

Background:

Juxtaarticular giant cell tumors around the knee are common and pose a special problem of reconstruction after tumor excision. This article analyzes the functional outcome after resection of juxtaarticular giant cell tumors around the knee and replacement by custom mega prosthetic arthroplasty.

Materials and Methods:

One hundred and forty-three patients with juxtaarticular giant cell tumors around the knee with mean age of 30.8 years (range 15 to 64 years) underwent resection and replacement by custom mega prosthetic arthroplasty during the period 1994 to 2005. Eighty-one patients were males and 62 were females. Fourteen patients were in Enneking Stage 2 while 129 patients were in Stage 3. Distal femur was involved in 87 patients and proximal tibia in 56 patients. Forty patients presented with pathological fracture at the time of diagnosis. The technique of sleeve resection of the quadriceps musculature was followed to achieve local clearance in distal femoral tumors, and for proximal tibial lesions resection of the tumor-bearing part and a medial gastronemius rotation flap was used routinely. The prosthesis used was a rotating hinge custom mega prosthesis manufactured locally.

Results:

The mean follow-up was 5.4 years (1.5 years to 11 years). Functional results were analyzed using Enneking criteria. Excellent results were obtained in 90 patients (62%) and 39 patients had good (27%) results. Periprosthetic fracture (8.3%) and infection (6.9%) were the most common complications followed by aseptic loosening (4.2%). Recurrence of lesion was found in only one patient (0.69%) who was managed with wide local excision.

Conclusion:

Custom mega prosthetic arthroplasty is effective in achieving the desired goals of reconstruction with good functional results and least complications in selected patients.  相似文献   
999.
Traditional approaches to revascularization for atherosclerotic ostial renal artery stenosis (RAS) have been suboptimal because of the invasiveness and relatively high perioperative morbidity and mortality of surgery and the low rates of success and long-term patency with percutaneous renal angioplasty (PTRA). We report our 5-year (1991 to 1996) experience with the intravascular stent (Palmaz stent; Johnson & Johnson, Miami Lakes, FL) for the treatment of ostial RAS in 129 patients (63 men, 66 women) and 148 arteries. The mean age of the patients was 71+/-10 years; 98% were hypertensive and 57% had renal dysfunction. Angiographic characteristics of RAS were unilateral in 78%, bilateral in 15%, and single kidney in 7%. The technical success rates were 98% for stent versus 11% for PTRA in the ostial location. The stent restenosis rate (angiographic) was 14% at 8+/-5 months. Systolic and diastolic blood pressures were as follows: baseline, 158+/-3 and 84+/-2 mm Hg; 6 months, 149+/-3 and 81+/-2 mm Hg; 12 months, 149+/-3 and 79+/-2 mm Hg; and 24 months, 135+/-3 and 79+/-2 mm Hg. Follow-up values were significantly lower than baseline (P < 0.05). The number of medications for hypertension initially decreased from 2.2+/-0.1 at baseline to 1.6+/-0.1 and 1.8+/-0.1 at 1 and 3 months, respectively (P < 0.05). By 6 months, however, the number of medications had increased and was not significantly different from before stent placement. Renal function was stable in the group as a whole: Cockroft-Gault creatinine clearance (C-G CrCl) at baseline was 40+/-2 mL/min; at 6 months, 36+/-3 mL/min; at 12 months, 39+/-3 mL/min; and at 24 months, 39+/-4 mL/min. When stratified by degree of renal function, values were similarly stable. Patients with a baseline serum creatinine level of 2 mg/dL or less had C-G CrCl values as follows: baseline, 53+/-3 mg/dL; 6 months, 43+/-4 mg/dL; 12 months, 46+/-4 mg/dL; and 24 months, 52+/-5 mg/dL. Those with a baseline serum creatinine level greater than 2 mg/dL had C-G CrCl values as follows: baseline, 26+/-2 mg/dL; 6 months, 31+/-4 mg/dL; 12 months, 32+/-6 mg/dL; and 24 months, 23+/-3 mg/dL. Of eight patients who were dialysis dependent, four (50%) recovered renal function with a mean serum creatinine level of 2.3+/-0.5 mg/dL at 15+/-6 months (range, 9 to 24 months). Stent placement for the treatment of atherosclerotic ostial RAS has a high success rate and a low rate of restenosis. Control of hypertension improves in most patients. Renal function stabilizes or improves in the majority of patients, even those with severe renal failure. These favorable outcomes are maintained long term.  相似文献   
1000.
Neurophysiological studies in non-human primates have identified saccade-related neuronal activity in cortical regions including frontal (FEF), supplementary (SEF) and parietal eye fields. Lesion and neuroimaging studies suggest a generally homologous mapping of the oculomotor system in humans; however, a detailed mapping of the precise anatomical location of these functional regions has not yet been achieved. We investigated dorsal frontal and parietal cortex during a saccade task vs. central fixation in 10 adult subjects using functional magnetic resonance imaging (fMRI). The FEF were restricted to the precentral sulcus, and did not extend anteriorly into Brodmann area 8, which has traditionally been viewed as their location in humans. The SEF were located in cortex along the interhemispheric fissure and extended minimally onto the dorsal cortical surface. Parietal activation was seen in precuneus and along the intraparietal sulcus, extending into both superior and inferior parietal lobules. These findings localize areas in frontal and parietal cortex involved in saccade generation in humans, and indicate significant differences from the macaque monkey in both frontal and parietal cortex. These differences may have functional implications for the roles these areas play in visuomotor processes.   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