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   39528篇
  免费   1993篇
  国内免费   158篇
耳鼻咽喉   329篇
儿科学   735篇
妇产科学   488篇
基础医学   5568篇
口腔科学   1100篇
临床医学   2776篇
内科学   9838篇
皮肤病学   921篇
神经病学   3067篇
特种医学   1487篇
外科学   5950篇
综合类   168篇
一般理论   1篇
预防医学   1474篇
眼科学   765篇
药学   2808篇
中国医学   77篇
肿瘤学   4127篇
  2023年   176篇
  2022年   319篇
  2021年   715篇
  2020年   358篇
  2019年   523篇
  2018年   698篇
  2017年   557篇
  2016年   641篇
  2015年   621篇
  2014年   906篇
  2013年   1140篇
  2012年   1784篇
  2011年   1972篇
  2010年   1051篇
  2009年   1050篇
  2008年   1760篇
  2007年   1946篇
  2006年   1952篇
  2005年   1968篇
  2004年   1855篇
  2003年   1912篇
  2002年   1978篇
  2001年   1494篇
  2000年   1476篇
  1999年   1298篇
  1998年   544篇
  1997年   407篇
  1996年   369篇
  1995年   318篇
  1994年   264篇
  1993年   284篇
  1992年   950篇
  1991年   838篇
  1990年   756篇
  1989年   762篇
  1988年   692篇
  1987年   700篇
  1986年   608篇
  1985年   577篇
  1984年   378篇
  1983年   318篇
  1982年   170篇
  1979年   248篇
  1978年   184篇
  1977年   156篇
  1975年   157篇
  1974年   157篇
  1973年   174篇
  1969年   155篇
  1967年   156篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Although dose reduction of S‐1 is recommended for patients with impaired renal function, dose modification for such patients has not been prospectively evaluated. The aim of the present study was to investigate the pharmacokinetic parameters of 5‐fluorouracil, 5‐chloro‐2,4 dihydroxypyridine and oteracil potassium, and to review the recommended dose modification of S‐1 in patients with renal impairment. We classified patients receiving S‐1 into 4 groups according to their renal function, as measured using the Japanese estimated glomerular filtration rate (eGFR) equation. The daily S‐1 dose was adjusted based on the patient's eGFR and body surface area. Blood samples were collected for pharmacokinetic analysis. A total of 33 patients were enrolled and classified into 4 groups as follows: 10 patients in cohort 1 (eGFR ≥ 80 mL/min/1.73 m2), 10 patients in cohort 2 (eGFR = 50‐79 mL/min/1.73 m2), 10 patients in cohort 3 (eGFR = 30‐49 mL/min/1.73 m2), and 3 patients in cohort 4 (eGFR < 30 mL/min/1.73 m2). Those in cohorts 3 and 4 treated with an adjusted dose of S‐1 showed a similar area under the curve for 5‐fluorouracil (941.9 ± 275.6 and 1043.5 ± 224.8 ng/mL, respectively) compared with cohort 2 (1034.9 ± 414.3 ng/mL). Notably, while there was a statistically significant difference between cohort 1 (689.6 ± 208.8 ng/mL) and 2 (= 0.0474) treated with an equal dose of S‐1, there was no significant difference observed in the toxicity profiles of the cohorts. In conclusion, dose adjustment of S‐1 in patients with impaired renal function using eGFR is appropriate and safe.  相似文献   
2.
BACKGROUND Minimally invasive surgery for gastric cancer(GC) has gained widespread use as a safe curative procedure especially for early GC.AIM To determine risk factors for postoperative complications after minimally invasive gastrectomy for GC.METHODS Between January 2009 and June 2019, 1716 consecutive patients were referred to our division for primary GC. Among them, 1401 patients who were diagnosed with both clinical and pathological Stage Ⅲ or lower GC and underwent robotic gastrectomy(RG) or laparoscopic gastrectomy(LG) were enrolled. Retrospective chart review and multivariate analysis were performed for identifying risk factors for postoperative morbidity.RESULTS Morbidity following minimally invasive gastrectomy was observed in 7.5% of the patients. Multivariate analyses demonstrated that non-robotic minimally invasive surgery, male gender, and an operative time of ≥ 360 min were significant independent risk factors for morbidity. Therefore, morbidity was compared between RG and LG. Accordingly, propensity-matched cohort analysis revealed that the RG group had significantly fewer intra-abdominal infectious complications than the LG group(2.5% vs 5.9%, respectively; P = 0.038), while no significant differences were noted for other local or systemic complications.Multivariate analyses of the propensity-matched cohort revealed that non-robotic minimally invasive surgery [odds ratio = 2.463(1.070–5.682); P = 0.034] was a significant independent risk factor for intra-abdominal infectious complications.CONCLUSION The findings showed that robotic surgery might improve short-term outcomes following minimally invasive radical gastrectomy by reducing intra-abdominal infectious complications.  相似文献   
3.
4.
5.
Early onset periodontitis is rarely seen in infants, though often leads to an acute and serious clinical course when encountered in such patients. Autoimmune neutropenia presents systemic and dental symptoms, as depressed resistance to bacterial infection is caused by a disorder that reduces the number of neutrophils. This disease can result in not only gingival inflammation but also destruction of periodontal tissues, such as attachment loss, alveolar bone absorption, and early tooth loss in primary as well as mixed dentition. Here, we report treatment of a child with marginal periodontitis from the age of 3 years–7 years 9 months. No systemic manifestations were noted until 3 years of age, thus the patient had never received a detailed examination or medication related to the disease. Following examinations at our department, we referred the patient to a pediatrician at our university hospital for possible systemic disease, who made a diagnosis of autoimmune neutropenia. Although administration of antibiotics and professional dental care were continued, neutrophil count was not increased and progressive periodontal destruction was observed. Extraction of teeth with poor prognosis was performed and a prosthetic strategy for the missing teeth developed. It is important to recognize that periodontitis along with autoimmune neutropenia can appear in infants, even though the incidence is quite low. Early detection and early treatment of this disease is necessary for delaying progression of periodontitis and optimal occlusal induction of permanent teeth.  相似文献   
6.
7.
8.
9.
We describe our methods and outcomes of multidisciplinary treatments in patients with unresectable hilar cholangiocarcinoma. Fifty‐seven patients with a known outcome were enrolled. Thirty‐four of 57 patients were treated and evaluated by salvage therapy. For salvage therapy, we used internal and external radiotherapy, photodynamic therapy, YAG laser therapy and microwave coagulation therapy. The median survival time was 548 days for the group receiving salvage therapy and 198 days for the group not receiving this treatment. In conclusion, although no randomization of the patients was performed in this retrospective study, our present data provide convincing evidence that salvage therapy is a useful therapeutic approach for unresectable hilar cholangiocarcinomas.  相似文献   
10.
Background and Aims: Video capsule endoscopy (VCE) has become increasingly important as a simple method for observing the entire small intestine. The indications for VCE are obscure gastrointestinal bleeding and investigation of Crohn’s disease (CD). However, the correlation between endoscopic findings obtained by VCE and clinical findings in known cases of CD is not clear, and we therefore investigated this in the present study. Patients and methods: In 30 patients with known CD (Crohn’s disease activity index [CDAI] 0–420; median = 158.3), double contrast enteroclysis (ENT) was performed 1–3 weeks prior to VCE. The relationship between the VCE findings and hematological analysis/CDAI was examined. Results: In 17 of 30 patients, the entire small intestine could be investigated by VCE, whereas in the remaining 13 patients the terminal ileum could not be investigated. The following exhibited positive correlations: total lesions and CDAI (correlation coefficient values: rs = 0.661, adjusted P < 0.0061), ulcers and C‐reactive protein (CRP) (rs = 0.607, adjusted P < 0.0061), total lesions and CRP (rs = 0.604, adjusted P < 0.0061). Conclusions: Analysis with VCE suggests that CDAI and CRP indicate the activity of intestinal lesions in patients with known CD, and that CRP, in particular, is associated with the activity of ulcerative lesions of the intestine. This may contribute to revised guidelines for VCE in the future.  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