全文获取类型
收费全文 | 228032篇 |
免费 | 4468篇 |
国内免费 | 109篇 |
专业分类
耳鼻咽喉 | 1648篇 |
儿科学 | 8843篇 |
妇产科学 | 4487篇 |
基础医学 | 23149篇 |
口腔科学 | 2061篇 |
临床医学 | 20684篇 |
内科学 | 39660篇 |
皮肤病学 | 1403篇 |
神经病学 | 21451篇 |
特种医学 | 9823篇 |
外科学 | 33127篇 |
综合类 | 2889篇 |
一般理论 | 109篇 |
预防医学 | 25443篇 |
眼科学 | 3469篇 |
药学 | 12945篇 |
中国医学 | 684篇 |
肿瘤学 | 20734篇 |
出版年
2023年 | 267篇 |
2022年 | 239篇 |
2021年 | 1016篇 |
2020年 | 695篇 |
2019年 | 1059篇 |
2018年 | 22945篇 |
2017年 | 18179篇 |
2016年 | 20415篇 |
2015年 | 2105篇 |
2014年 | 2459篇 |
2013年 | 3435篇 |
2012年 | 10759篇 |
2011年 | 24988篇 |
2010年 | 20940篇 |
2009年 | 13510篇 |
2008年 | 23072篇 |
2007年 | 25501篇 |
2006年 | 4370篇 |
2005年 | 6118篇 |
2004年 | 7123篇 |
2003年 | 7868篇 |
2002年 | 5743篇 |
2001年 | 724篇 |
2000年 | 736篇 |
1999年 | 621篇 |
1998年 | 874篇 |
1997年 | 802篇 |
1996年 | 562篇 |
1995年 | 575篇 |
1994年 | 516篇 |
1993年 | 395篇 |
1992年 | 279篇 |
1991年 | 288篇 |
1990年 | 308篇 |
1989年 | 271篇 |
1988年 | 236篇 |
1987年 | 207篇 |
1986年 | 181篇 |
1985年 | 190篇 |
1984年 | 202篇 |
1983年 | 180篇 |
1982年 | 235篇 |
1981年 | 203篇 |
1980年 | 191篇 |
1979年 | 93篇 |
1978年 | 119篇 |
1976年 | 62篇 |
1974年 | 85篇 |
1938年 | 60篇 |
1932年 | 56篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Betsy D. Kennard Susan G. Silva Simon Tonev Paul Rohde Jennifer L. Hughes Benedetto Vitiello Christopher J. Kratochvil John F. Curry Graham J. Emslie Mark Reinecke John March 《Journal of the American Academy of Child and Adolescent Psychiatry》2009,48(2):186-195
ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment. 相似文献
92.
93.
Introduction
Although ependymoma is the third most common pediatric brain tumor, we know little about the genetic/epigenetic basis of its initiation, maintenance, or progression. This is due in part to the heterogeneity of the disease, as well as the small sample size of the cohorts analyzed in most studies. 相似文献94.
Peter Angelos 《World journal of surgery》2009,33(4):609-611
95.
Kentaroh Miyoshi Minoru Naito Tsuyoshi Ueno Shinji Hato Hideo Ino 《General thoracic and cardiovascular surgery》2009,57(11):629-632
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
96.
97.
98.
Emmanuel J Favaloro Roslyn Bonar Elizabeth Duncan Susan Rodgers Katherine Marsden 《Blood coagulation & fibrinolysis》2007,18(5):441-448
The PFA-100 is a relatively new laboratory instrument, first described in 1995. There have since been numerous studies assessing its utility as a screening tool for platelet dysfunction and/or von Willebrand's disease (VWD). The PFA-100 displays variable sensitivity to different types of platelet disorders, as well as to antiplatelet medication (e.g. aspirin), with similar caveats for monitoring of primary haemostasis-promoting therapies in platelet dysfunction. There is therefore considerable uncertainty regarding its utility within this context, and we have accordingly performed an audit of usage among participants of the Royal College of Pathologists of Australasia Quality Assurance Program. Of 105 laboratories surveyed, 40 responded that they performed platelet function testing, with 26 (65%) further indicating they utilized the PFA-100. We report a wide variety of laboratory usage among these users, including numbers of tests performed [annual median (range) = 270 (15-6000)], sources of requests (clinical sources and localities), testing criteria and follow-up action. Most tests were completed within 4 h of collection, as recommended by the manufacturer, and most tests were performed as a replacement, or as a preliminary screen of platelet function (i.e. classical aggregation). Most abnormal findings, however, were attributed to antiplatelet medication such as aspirin. 相似文献
99.
100.
Timothy M. Pawlik Kelly Olino Ana Luiza Gleisner Michael Torbenson Richard Schulick Michael A. Choti 《Journal of gastrointestinal surgery》2007,11(7):860-868
Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury
and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with
preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present,
was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who
underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on
demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority
of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and
oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns
of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin
(all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received
irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%)
and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases,
preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic
injury after preoperative chemotherapy was regimen-specific.
Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida. 相似文献