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   2239篇
  免费   125篇
  国内免费   22篇
耳鼻咽喉   8篇
儿科学   168篇
妇产科学   41篇
基础医学   233篇
口腔科学   56篇
临床医学   199篇
内科学   571篇
皮肤病学   41篇
神经病学   136篇
特种医学   493篇
外科学   152篇
综合类   29篇
预防医学   83篇
眼科学   14篇
药学   62篇
中国医学   4篇
肿瘤学   96篇
  2022年   5篇
  2021年   11篇
  2020年   12篇
  2019年   19篇
  2018年   31篇
  2017年   17篇
  2016年   28篇
  2015年   38篇
  2014年   45篇
  2013年   84篇
  2012年   50篇
  2011年   47篇
  2010年   88篇
  2009年   71篇
  2008年   52篇
  2007年   56篇
  2006年   62篇
  2005年   47篇
  2004年   44篇
  2003年   38篇
  2002年   44篇
  2001年   50篇
  2000年   50篇
  1999年   44篇
  1998年   145篇
  1997年   122篇
  1996年   128篇
  1995年   95篇
  1994年   78篇
  1993年   84篇
  1992年   30篇
  1991年   34篇
  1990年   24篇
  1989年   68篇
  1988年   51篇
  1987年   58篇
  1986年   52篇
  1985年   57篇
  1984年   33篇
  1983年   33篇
  1982年   41篇
  1981年   24篇
  1980年   44篇
  1979年   17篇
  1978年   27篇
  1977年   22篇
  1976年   34篇
  1975年   27篇
  1974年   7篇
  1966年   4篇
排序方式: 共有2386条查询结果,搜索用时 0 毫秒
41.
42.
目的:探讨输尿管硬镜在尿路疾病治疗中的应用效果。方法:对1000例尿路结石、输尿管及尿道狭窄、输尿管息肉、梗阻、异物存留等患者,均以输尿管硬镜配合其他设备进行治疗。结果:肾内结石34例治愈率76.5%,输尿管结石、膀胱及尿道结石治愈率为94.5%~99.8%;泌尿道狭窄治愈率66.7%~75%;33例泌尿道异物取出率97%。结论:基层医院在尿路疾病治疗中,根据病变的不同部位,将输尿管硬镜灵活配合现有并不高档的设备,同样可以取得较好的微创手术效果。  相似文献   
43.

Introduction

Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.

Methods

A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.

Results

From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.

Conclusions

The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay.  相似文献   
44.
We observed the effects of sodium bicarbonate supplement on bone mass in rats on strenuous treadmill training. Sixty female Wistar rats (93-days-old; mean initial weight 261 ± 16 g) were studied. One group of 15 rats was killed at the beginning of the experiments (basal control group), while another group of 15 rats was not manipulated (Exer−NaB−). Another group of 15 rats was exercised but did not receive sodium bicarbonate (Exer+NaB−), while the final group of 15 rats exercised and received sodium bicarbonate (Exer+NaB+) at a dose of 0.05 mg/kg/day, administered by esophageal catheter on exercise days. These rats were killed at the end of 11 weeks. Femoral and vertebral length, weight, and bone mineral content (BMC) and density (BMD) were measured. According to anova with the Tukey–Kramer test, femur length and weight, vertebral weight, femur BMC and BMD, vertebral BMC and BMD and the ratio between femur and vertebral BMC and final body weight, and plasma bicarbonate were lower in the basal control and Exer+NaB− groups than in the two other groups (P < 0.005–0.0001). Overall, there was a positive correlation between femur and vertebral BMC and femur BMC and length (P < 0.0001 for all). Only in the Exer+NaB− group was there a positive association between plasma bicarbonate levels and femur length (r = 0.78; P < 0.0005). Our study demonstrates the adverse effects of strenuous exercise on bone, and the usefulness of sodium bicarbonate supplements in preventing and minimized these effects. Received: May 1, 2000 / Accepted: August 11, 2000  相似文献   
45.
BACKGROUND: The objective of this study was to determine whether the outcome of mid-urethral sling procedures is influenced by the body mass index of Korean women suffering from stress urinary incontinence (SUI). METHODS: A total of 285 women, ranging in age from 28 to 80 years (mean 55.4), all of whom were followed up for at least 6 months, were ultimately included in this study. The patients were classified as follows: normal weight, 18.5-23 kg/m2; overweight, 23-27.5 kg/m2; obesity, 27.5 kg/m2 or higher. RESULTS: We noted bladder perforations in 11 cases (4.9%, 3.8% and 2.2% in the normal weight, overweight, and obesity groups, respectively; P = 0.449). We determined there to be no significant differences among the three groups with regard to cure rate (P = 0.173). The rates of postoperative urinary retention were 9.9% in the normal weight group, 10.1% in the overweight group, and 15.6% in the obesity group (P = 0.396). We determined there to be no significant differences among the three groups with regard to the persistence of urgency (P = 0.312). Seventy-nine patients (27.7%) exhibited symptoms indicative of voiding disorder (hesitancy, poor flow, or sensations of incomplete emptying). The postoperative development of these voiding symptoms was not significantly different among the three groups (P = 0.106). CONCLUSION: Our results demonstrate both the feasibility and the safety of mid-urethral sling procedures for obese Korean women who suffer from SUI. Additional studies, including prospective randomized trials with longer follow-up periods, will be required in order to confirm these findings.  相似文献   
46.
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
47.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
48.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
49.
Magnetization transfer contrast: MR imaging of the knee   总被引:1,自引:0,他引:1  
  相似文献   
50.
Heart disease is the leading cause of non-cancer death in childhood cancer survivors. to determine the prevalence of subclinical cardiac dysfunction using speckle tracking and compare its results with those obtained by classical methods of assessing left ventricular function and its relationship with different factors to identify the population at higher risk. Echocardiographic assessment of left ventricular function included ejection fraction, tissue Doppler, longitudinal/circumferential strains and biochemical parameters (troponin-T and Pro-BNP) in a cohort of 57 survivors of childhood acute leukaemia with at least 10 years since diagnosis. Ventricular dysfunction was found in 5.2% of patients in M-mode (ejection fraction—EF?<?53% with a reduction in the EF?≥?10%) and in 7% of patients with Simpson’s method, compared with 21.05 and 8.8% with suboptimal global longitudinal strain (GLS) and global circumferential strain, respectively. The GLS alteration was significantly correlated with lower values of left ventricular systolic function and was associated with high tumour risk (odds ratio [OR] 13.8), cumulative doses of anthracyclines?≥?250 mg/m2 (OR 7.6) and radiotherapy (OR 7.19). Biomarkers were not useful for the diagnosis of subclinical cardiomyopathy. Good reproducibility was obtained, with an intraobserver correlation of 93.6% and an interobserver correlation of 89.2% in the GLS. The alteration of the GLS was more prevalent than the alteration in the EF and was associated with the treatment received and high tumour risk. strain imaging seems to be a powerful tool to identify an increased number of survivor with an early myocardial injury.  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