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   2365篇
  免费   151篇
  国内免费   15篇
耳鼻咽喉   12篇
儿科学   105篇
妇产科学   57篇
基础医学   307篇
口腔科学   57篇
临床医学   231篇
内科学   482篇
皮肤病学   29篇
神经病学   135篇
特种医学   76篇
外科学   337篇
综合类   55篇
预防医学   202篇
眼科学   56篇
药学   252篇
中国医学   11篇
肿瘤学   127篇
  2023年   29篇
  2022年   37篇
  2021年   76篇
  2020年   34篇
  2019年   84篇
  2018年   76篇
  2017年   59篇
  2016年   69篇
  2015年   56篇
  2014年   69篇
  2013年   119篇
  2012年   144篇
  2011年   146篇
  2010年   83篇
  2009年   60篇
  2008年   117篇
  2007年   104篇
  2006年   103篇
  2005年   121篇
  2004年   100篇
  2003年   110篇
  2002年   92篇
  2001年   61篇
  2000年   61篇
  1999年   56篇
  1998年   22篇
  1997年   13篇
  1996年   11篇
  1995年   10篇
  1994年   10篇
  1993年   14篇
  1992年   27篇
  1991年   42篇
  1990年   34篇
  1989年   24篇
  1988年   22篇
  1987年   25篇
  1986年   28篇
  1985年   22篇
  1984年   14篇
  1982年   14篇
  1979年   11篇
  1977年   8篇
  1975年   7篇
  1974年   14篇
  1972年   9篇
  1971年   8篇
  1970年   11篇
  1969年   13篇
  1966年   6篇
排序方式: 共有2531条查询结果,搜索用时 31 毫秒
31.
BACKGROUND: The aim of this study was to evaluate feasibility and tolerability of the three-drug combination of paclitaxel, ifosfamide and carboplatin (TIC) in patients with advanced non-small-cell lung cancer. The specific objectives of the study were: (i) to define the dose-limiting toxicities (DLTs) and the maximum-tolerated dose of ifosfamide administered as part of the combination; and (ii) to determine the overall response rate and overall survival of patients treated with this regimen. PATIENTS AND METHODS: Patients with untreated, stage IIIB (pleural effusion) or stage IV non-small-cell lung cancer were enrolled in one of three cohorts. Patients received paclitaxel 200 mg/m(2) as a 1-h infusion on day 1 with carboplatin at an area under the concentration-time curve (AUC) of 6 mg.min/ml on day 2. For dose level I, ifosfamide was administered at a dose of 2 g/m(2) on days 1 and 2. For dose levels II and III, the dose of ifosfamide was decreased to 1.5 g/m(2) on days 1 and 2 and the dose of carboplatin was decreased to AUC 5 mg.ml/min. Therapy for dose levels I and III included filgrastim support (5 micro g/kg/day), which was initiated on day 3 and continued until after day 11 or until an absolute neutrophil count >10 000/ micro l. Treatment cycles were repeated every 21 days. Once the phase II dose was established, a full cohort of patients received therapy at this dose level to examine further the regimen's activity and tolerability. RESULTS: Neutropenia was the DLT encountered for dose levels I and II. No DLT was encountered in the initial six patients treated at dose level III, and therefore this dose level was declared the recommended phase II dose. A total of 49 patients were treated at the recommended phase II dose. The predominant non-hematological toxicity encountered with this triplet regimen was cumulative peripheral neuropathy. Of the 65 eligible patients enrolled in this study, 17 (26%) responded. There were 15 patients with partial responses (23%), two with regression, and 26 with stabilization of disease (40%). Median progression-free and overall survival were 4.8 and 9.4 months, respectively. CONCLUSIONS: The combination TIC is well-tolerated. This triplet regimen produced response and survival rates in advanced non-small-cell lung cancer similar to those of other current combination chemotherapy regimens.  相似文献   
32.
A great variety of foreign bodies in the urethra have been reported in the literature. Mostly, these cases were reported to emphasize the unusual nature of the objects requiring technical modifications for their removal. We report an interesting case of self introduced open thumb forceps into the urethra and technique of its retrieval.  相似文献   
33.
34.
BACKGROUND: The purpose of the present paper was (i) to identify trends in in-hospital mortality after transurethral resection of the prostate (TURP) in Victorian public hospitals; and (ii) to explore associations between in-hospital mortality after TURP and age, adverse events, type of admission (emergency/planned), location of the hospital (metropolitan/rural), teaching status of the hospital and length of stay. METHODS: Trends in in-hospital mortality after TURP and the associations between in-hospital mortality and the aforementioned variables were studied using International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) coded Victorian hospital morbidity data from public hospitals between 1987-88 and 1994-95. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were based on univariate and multivariate logistic regression, respectively. RESULTS: After adjustment for age, comorbidity, and other confounding variables, the trend in mortality reduction over time was highly significant (P for trend < 0.0001, 95% CI for trend: 0.84-0.95). Highly significant associations with mortality were observed for emergency admissions (OR = 1.99, P < 0.0001), presence of adverse events (OR = 2.69, P < 0.0001), length of hospital stay (P for trend < 0.0001, 95% for trend: 1.88-2.15) and age (P for trend < 0.0001; 95% CI for trend: 1.26-1.48). CONCLUSIONS: Routinely collected data from hospitals can provide tentative evidence of improved effectiveness of a surgical treatment, provided analysis takes careful account of potential sources of bias, especially those related to possible changes in case selection over time. These kinds of data should stimulate a joint effort between clinicians, quality assurance experts and epidemiologists to confirm this attribution, and to locate the causative factors.  相似文献   
35.
There have been conflicting reports as to whether olanzapine produces lower occupancy of striatal dopamine D(2)/D(3) receptor than typical antipsychotic drugs and preferential occupancy of extrastriatal dopamine D(2)/D(3) receptors. We performed [(18)F] fallypride PET studies in six schizophrenic subjects treated with olanzapine and six schizophrenic subjects treated with haloperidol to examine the occupancy of striatal and extrastriatal dopamine receptors by these antipsychotic drugs. [(18)F] setoperone PET studies were performed in seven olanzapine-treated subjects to determine 5-HT(2A) receptor occupancy. Occupancy of dopamine D(2)/D(3) receptors by olanzapine was not significantly different from that seen with haloperidol in the putamen, ventral striatum, medial thalamus, amygdala, or temporal cortex, that is, 67.5-78.2% occupancy; olanzapine produced no preferential occupancy of dopamine D(2)/D(3) receptors in the ventral striatum, medial thalamus, amygdala, or temporal cortex. There was, however, significantly lower occupancy of substantia nigra/VTA dopamine D(2)/D(3) receptors in olanzapine-treated compared to haloperidol-treated subjects, that is, 40.2 vs 59.3% (p=0.0014, corrected for multiple comparisons); in olanzapine-treated subjects, the substantia nigra/VTA was the only region with significantly lower dopamine D(2)/D(3) receptor occupancy than the putamen, that is, 40.2 vs 69.2% (p<0.001, corrected for multiple comparison). Occupancy of 5-HT(2A) receptors was 85-93% in the olanzapine- treated subjects. The results of this study demonstrated that olanzapine does not produce preferential occupancy of extrastriatal dopamine D(2)/D(3) receptors but does spare substantia nigra/VTA receptors. Sparing of substantia nigra/VTA dopamine D(2)/D(3) receptor occupancy may contribute to the low incidence of extrapyramidal side effects in olanzapine-treated patients.  相似文献   
36.
Trautmann's triangle (TT) faces the cerebellopontine angle and is exposed during posterior transpetrosal approaches. However, reports on the morphometric analysis of this structure are lacking in the literature. The goal was to better understand this important operative corridor. TT was exposed from an external approach (transmastoid) in ten cadavers (20 sides) and from an internal approach on 20 dry adult temporal bones. Measurements included calculation of the area of TT and the distance of the endolymphatic sac from the anterior border of the sigmoid sinus. The area range of TT was 45–210 mm2 (mean 151 mm2; SD 37 mm2). Three types of triangles were identified based on area. Type I triangles had areas less than 75 mm2, Type II areas were 75–149 mm2, and Type III areas were 150 mm2 and greater. These types were observed in 37.5%, 35%, and 27.5% of sides, respectively. The distance from the jugular bulb's anterior border to the posterior border of the posterior semicircular canal ranged from 6 to 11 mm (mean 8.5 mm). The endolymphatic sac was located in the inferior portion of TT and traveled anterior to the sigmoid sinus. The horizontal distance from the anterior edge of the sigmoid sinus to the posterior edge of the endolymphatic sac ranged from 0 to 13.5 mm (mean 9 mm). Additional anatomic knowledge regarding TT may improve neurosurgical procedures in this region by avoiding intrusion into the endolymphatic sac and sigmoid sinus. Clin. Anat. 27:994–998, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
37.
Infection with Epstein–Barr virus (EBV) is associated with multiple sclerosis (MS), and patients with MS have an increased antibody response to some EBV antigens. The major antigens of EBV are only partly defined. Our hypothesis is that the antibody response to EBV is altered in MS. With ELISA, we found that antibodies to EB virions were increased in both serum and CSF of MS patients. Western blots demonstrated that there are multiple different antigens recognized. The antibody response was generally higher in MS to all EBV antigens, with particularly significant increases for certain antigens. We conclude that the antibody response to EBV in MS is generally increased with altered specificity.  相似文献   
38.
39.
40.
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