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   5442篇
  免费   241篇
  国内免费   30篇
耳鼻咽喉   129篇
儿科学   117篇
妇产科学   22篇
基础医学   747篇
口腔科学   113篇
临床医学   380篇
内科学   1326篇
皮肤病学   59篇
神经病学   229篇
特种医学   170篇
外科学   1064篇
综合类   24篇
预防医学   161篇
眼科学   42篇
药学   434篇
中国医学   1篇
肿瘤学   695篇
  2022年   61篇
  2021年   83篇
  2020年   52篇
  2019年   55篇
  2018年   86篇
  2017年   60篇
  2016年   82篇
  2015年   93篇
  2014年   111篇
  2013年   127篇
  2012年   221篇
  2011年   260篇
  2010年   123篇
  2009年   117篇
  2008年   207篇
  2007年   237篇
  2006年   247篇
  2005年   258篇
  2004年   262篇
  2003年   239篇
  2002年   241篇
  2001年   178篇
  2000年   203篇
  1999年   191篇
  1998年   63篇
  1997年   62篇
  1996年   55篇
  1995年   56篇
  1994年   54篇
  1993年   37篇
  1992年   121篇
  1991年   119篇
  1990年   115篇
  1989年   111篇
  1988年   121篇
  1987年   120篇
  1986年   120篇
  1985年   101篇
  1984年   70篇
  1983年   74篇
  1979年   44篇
  1978年   28篇
  1977年   36篇
  1974年   28篇
  1973年   38篇
  1972年   34篇
  1971年   37篇
  1970年   27篇
  1969年   30篇
  1968年   35篇
排序方式: 共有5713条查询结果,搜索用时 31 毫秒
1.
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in...  相似文献   
2.
One diagnostic criterion for metabolic syndrome is obesity from the accumulation of visceral fat; others include abdominal circumference and area of visceral fat as measured by computed tomography (CT) at the umbilical level. We evaluated visceral fat using frequency-selective excitation magnetic resonance (MR) imaging SPAIR (spectral attenuation with inversion recovery) water suppression THRIVE (3D T1-high resolution isotropic volume examination). Fifty of 70 slices with 2-mm interval were used to render and measure volume of visceral fat ranging within 10 cm of the umbilicus; the area of visceral fat at the umbilical level was also measured. Imaging was completed using breath hold within 14 s. Image processing was easier than using CT.  相似文献   
3.
A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
4.
5.
Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods.  相似文献   
6.
OBJECTIVE: To assess the functional results, health-related quality of life (QOL) outcomes, and complications in patients with an ileal neobladder in comparison to those with cutaneous diversion (ileal conduit and cutaneostomy). METHODS: Between September 1992 and February 2003, we consecutively performed an ileal neobladder (the Studer method) in 30 patients and cutaneous diversion in 38 patients. In August 2004, questionnaires were mailed to 54 patients. The questionnaire included the validated health-related quality of life (QOL) questionnaire, SF-36 General Health Survey, and a urinary incontinence questionnaire. We also evaluated the functional results in patients with an ileal neobladder and the postoperative complications in patients with both urinary diversions. RESULTS: The data from 41 patients (21 ileal neobladder procedures and 20 cutaneous diversions) were available for the analysis. No differences in the overall QOL were observed between the two groups. Complete daytime and night-time urinary continence was achieved in the 21 patients (100%) and 13 patients (61.9%), respectively. The mean value of the maximum flow rate was 15 +/- 12 mL/min in the 21 neobladder patients. There were 19 early complications in 18 patients (60.0%) and seven late complications in six patients (20.0%) with an ileal neobladder. However, there were 15 early complications in 14 patients (36.8%) and eight late complications in six patients (15.8%) with cutaneous diversions. CONCLUSION: The findings regarding the health-related QOL and the frequency of complications in the neobladder group and those in the cutaneous diversion group were similar. However, the functional results and the status of urinary continence in the neobladder patients were satisfactory.  相似文献   
7.
OBJECTIVE: Standard chemotherapy shows relatively low long-term survival in patients with poor-risk testicular germ cell tumor (GCT). First-line high-dose chemotherapy (HD-CT) may improve the result. High-dose carboplatin, etoposide, ifosfamide chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) was investigated as first-line chemotherapy in patients with advanced testicular GCT. METHODS: Fifty-five previously untreated testicular GCT patients with Indiana 'advanced disease' criteria received three cycles of bleomycin, etoposide and cisplatin (BEP) followed by one cycle of HD-CT plus PBSCT, if elevated serum tumor markers were observed after three cycles of the BEP regimen. RESULTS: Thirty patients were treated with BEP alone, because the tumor marker(s) declined to normal range. Twenty-five patients received BEP and HD-CT. One patient died of rhabdomyolysis due to HD-CT. Three and six (13% and 25%) out of 24 patients treated with BEP and HD-CT achieved marker-negative and marker-positive partial responses, respectively. The other patients achieved no change. Fifteen (63%) are alive and 14 (58%) are free of disease at a median follow-up time of 54 months. Severe toxicity included treatment-related death (4%). CONCLUSIONS: HD-CT with peripheral stem cell support can be successfully applied in a multicenter setting. HD-CT demonstrated modest anticancer activity for Japanese patients with advanced testicular GCT and was well tolerated. This regimen might be examined for further investigation in randomized trials in first-line chemotherapy for patients with poor-risk testicular GCT.  相似文献   
8.
Although the prevalence of a learned voiding dysfunction and non-neurogenic neurogenic bladder (NNB), which is one type of dysfunctional elimination syndrome, is considered to be relatively rare, the association of NNB with Down syndrome (DS) has been elucidated in male patients. We herein describe the occurrence of NNB in an adult female with DS. The diagnosis was confirmed after completely ruling out any neurological or anatomical anomalies that could be related to a lower urinary tract dysfunction. She had renal dysfunction and multiple obstructive uropathies for which clean intermittent catheterization was successfully introduced.  相似文献   
9.
To evaluate the effect of UFT, a mixture of ftorafur and uracil in a ratio of 1:4, in preventing postoperative recurrence of bladder cancer, we performed a randomized controlled study with a non-medication group as control. UFT was given orally 400 mg a day for 6 months. Of 111 patients, 56 were given UFT and 55 were followed up without any medication. The non-recurrence rate in the group treated with UFT was 62.8% after 1 year and 36.3% after 2 years of follow up, and that of the control group was 45.7% and 39.5%, respectively. The rate of non-recurrence in the UFT group was significantly higher (p less than 0.05) than that of the control group during the period of follow up for 2 years. The incidence of side effects was 6.8% in UFT patients. These results indicate the clinical usefulness of prophylactic administration of UFT for bladder cancer patients.  相似文献   
10.
The aim of this study was to establish a pressure ulcer model that visualizes the microcirculation, and to examine the participation of ischemia-reperfusion injury in the pathophysiology of pressure ulcers. An original system composed of a new skin fold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia-reperfusion injury, animals were divided into two groups: the compression-release group (n = 8), in which the animals received four cycles of compression-release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group (n = 8) in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day 1 (35 hours) after the first evaluation. The cyclic compression-release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia-reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. This finding supports the significant contribution of ischemia-reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation.  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