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   24474篇
  免费   1489篇
  国内免费   111篇
耳鼻咽喉   284篇
儿科学   704篇
妇产科学   692篇
基础医学   2678篇
口腔科学   585篇
临床医学   2008篇
内科学   5089篇
皮肤病学   301篇
神经病学   1332篇
特种医学   700篇
外国民族医学   7篇
外科学   4391篇
综合类   790篇
一般理论   19篇
预防医学   1840篇
眼科学   630篇
药学   2298篇
中国医学   258篇
肿瘤学   1468篇
  2023年   220篇
  2022年   640篇
  2021年   855篇
  2020年   555篇
  2019年   700篇
  2018年   852篇
  2017年   579篇
  2016年   522篇
  2015年   672篇
  2014年   929篇
  2013年   1183篇
  2012年   1725篇
  2011年   1674篇
  2010年   984篇
  2009年   794篇
  2008年   1297篇
  2007年   1331篇
  2006年   1263篇
  2005年   1180篇
  2004年   1024篇
  2003年   936篇
  2002年   777篇
  2001年   627篇
  2000年   563篇
  1999年   460篇
  1998年   186篇
  1997年   143篇
  1996年   140篇
  1995年   139篇
  1994年   84篇
  1993年   95篇
  1992年   239篇
  1991年   230篇
  1990年   209篇
  1989年   209篇
  1988年   173篇
  1987年   197篇
  1986年   154篇
  1985年   157篇
  1984年   130篇
  1983年   107篇
  1982年   66篇
  1981年   68篇
  1979年   110篇
  1978年   78篇
  1977年   84篇
  1975年   70篇
  1974年   66篇
  1973年   72篇
  1972年   67篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Abstract:   We present a case of a 13-year-old boy who developed signs and symptoms of neuropathic pain/early Complex Regional Pain Syndrome (CRPS) Type I, formerly known as Reflex Sympathetic Dystrophy (RSD), after spraining his ankle while wrestling. Aggressive pain control, using medications and sympatholytic blocks, with physical therapy and rehabilitation, led to the resolution of his painful condition. This prevented the disease from possibly progressing to a full-blown case of CRPS I (RSD) that is very challenging to treat.  相似文献   
22.
Partially edentulous patients with alveolar defects contraindicating implant placement were treated with bone grafts obtained from the mandibular symphysis. Complications encountered were minor and uneventful. Evaluation 4 months after surgery revealed minimal graft resorption, thus implant placement was possible in all potential sites. Advantages of the symphysis graft include easy access, availability of greater quantities of bone over other intraoral donor sites, low morbidity, no hospitalization, minimal discomfort, no alteration in ambulation, and no cutaneous scar. Compared with other bone regenerative methods for implant placement, a superior quality of bone was found and a shorter healing period is required. Results of this preliminary clinical investigation demonstrate that chin grafts offer a viable alternative for reconstruction of alveolar defects prior to dental implant placement.  相似文献   
23.
There are few records detailing the techniques and tribulations of early American surgeons who dared venture into the treacherous recess of the human orbit. The authors present a recently discovered letter written by a young woman who in 1841 underwent an orbital operation performed by the prominent New York City surgeon, Willard Parker. The letter details the patient's experiences in an era without anesthesia or antibiotics, and her subsequent development of conjunctival adhesions.  相似文献   
24.
Mixed-panic disorder patients (16/60, 27%) randomly assigned to receive blind placebo during a 40-week treatment study were defined as placebo responders based on combined criteria of Hamilton Anxiety Scale score percentage decreases below the median point (-42%), moderate to marked improvement on both clinician and patient Clinical Global Impressions scores, and panic-free at final treatment visit. These criteria applied separately also resulted in a similar clinical grouping and pattern of response. Differential patterns of response between responders and nonresponders occurred across most clinical measures of panic/anxiety. Responders experienced early improvement within the first week of double-blind treatment. This response progressed during treatment and tended to persist during taper and at followup 1 month later. Post-hoc analysis of demographic and clinical features at entrance into the study failed to characterize this stringently defined group of placebo responders.  相似文献   
25.
Coats'-type retinitis pigmentosa   总被引:3,自引:0,他引:3  
Coats'-like changes (i.e., retinal telangiectasia and/or exudative detachment) have been reported in as many as 1.2 to 3.6 percent of patients with retinitis pigmentosa. In severe cases this disorder may progress to total retinal detachment and visual loss in the context of longstanding retinitis pigmentosa. Forty-six cases of Coats'-type retinitis pigmentosa gathered from the literature are reviewed. Historical and epidemiological features, hereditary factors, clinical features, histopathological findings, pathogenesis, differential diagnosis, prognosis and possible treatment are discussed.  相似文献   
26.
27.
Although postoperative beta irradiation for prevention of pterygium recurrence is widely used, its complication rate has not been widely appreciated. Thirty-six patients underwent pterygium excision followed by irradiation with 90Sr to between 1600 and 5300 cGy (median 2400) in two to four fractions over 7 to 27 days. A median of three fields were used in each treatment course (range two to 10). Most patients had undergone previous treatment for their pterygia, including surgery alone (25 patients), or both surgery and irradiation (5 patients). Overall, recurrences developed in 10 eyes (28%). Recurrence occurred in one eye after re-irradiation (20%), compared to 9 of 31 (29%) previously non-irradiated eyes (p greater than 0.1). There was no association with number of excisions and recurrences, although all but 6 patients had undergone more than one excision. Thirteen patients (36%) developed complications including: epithelial defect or corneal thinning (3), symblepharon (5), cataract (4) and corneal ulceration (1). Complications developed in 4 of the 5 (80%) re-irradiated eyes compared to 9 of 31 (29%) previously non-irradiated eyes (p less than 0.05). The power of the statistical analysis was limited by sample size, but no significant association was observed between the development of complications or recurrences and total dose, number of abutting fields, number of previous surgical excisions or patient age, even when re-irradiated patients were excluded. Recently described calibration uncertainties with the 90Sr applicator may explain in part these complications. Alternatively, technical factors such as the number of fields or volume treated may play a role. Excessive complications and recurrences with the use of postoperative beta irradiation in this series emphasize the danger of re-treatment and the need for alternative safe and effective therapies.  相似文献   
28.
29.
Renal transplant recipients treated with cyclosporine (CS) have been reported to be at increased risk of thrombotic complications. The present study was intended to examine the blood coagulation, fibrinolytic, and inhibitory systems in such patients. Eight transplant recipients on maintenance immunosuppression with CS and prednisone were studied. Five transplant recipients maintained on azathioprine (AZA) and prednisone and 32 normal volunteers served as controls. Plasma antigen concentrations and/or activities of various proteins in the above pathways were measured. Both the CS and AZA groups exhibited significant elevations of factor IX activity, von Willebrand factor (vWF), D-dimer, protein C and tissue type plasminogen activator (t-PA) levels when compared with the normal controls. In addition, CS group showed a significant elevation of alpha 2-macroglobulin activity and AZA group showed a significant reduction in factor XII activity when compared with the normal controls. Comparison of data from CS and AZA groups revealed higher factor XII activity and vWF concentration in the former group. In conclusion, transplant recipients treated with long-term cyclosporine and prednisone exhibited significant elevation of plasma vWF, D-dimer and protein C concentrations. In addition, both CS and AZA-treated transplant recipients showed increased plasma concentrations of D-dimer and t-PA. The latter observations suggest in vivo thrombin generation, fibrin formation and degradation.  相似文献   
30.
A total of 321 patients with localized adenocarcinoma of the prostate treated by modified pelvic lymphadenectomy, Iridium-192 implant, and external beam iridium radiation were retrospectively reviewed. Analysis covered 8 years between 1981 and 1989 with a median population age of 72 (range 42 through 82 years). Disease-free survival for the entire group is 69% at 5 years with a median follow-up of 34 months (range 1.5 months to 98.5 months). As expected, both bulkier disease and positive nodal status adversely affected 5-year disease-free survival (p = 0.0001 for both). For tumors stage T1b (A2), T2a (B1), T2b (B2), T3 (C) the disease-free survival is 89.5%, 89.9%, 64.7%, and 48.8%, respectively; for NO disease 5-year disease-free survival is 76.5% versus N1/N2 disease with 5-year disease-free survival of 33.2%. Local control was excellent except for bulkier disease (p = 0.009). Tumors T1b, T2a, T2b, and T3 have 60-month local control rates of 95%, 93%, 83.6%, and 73.1%, respectively. Histologic grade also affected disease-free survival and local control with grade 1, grade 2, grade 3 showing 81.2%, 65.7%, and 45.1% disease-free survival at 5 years; and 93.6%, 82.2%, and 72.4% local control at 5 years. Estimates obtained using Kaplan-Meier method. Radiation induced morbidity was analyzed separately for all patients, there were 41 patients (13% of total) with 54 documented complications. There were no Grade 4 or 5 complications as per RTOG categories. Only 3 cases showed grade 3 complications (1%) and 51 cases showed grade 2 complications (15.9%). Grade 1 complications were not recorded. Of the grade 2 and grade 3 complications 30 were GU and 22 were rectal. The morbidity associated with combined interstitial implantation by transperineal percutaneous template and external beam iridium radiation for the localized prostate cancer is minimal with excellent local control and disease-free survival.  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