全文获取类型
收费全文 | 199888篇 |
免费 | 3396篇 |
国内免费 | 2154篇 |
专业分类
耳鼻咽喉 | 1307篇 |
儿科学 | 6851篇 |
妇产科学 | 3231篇 |
基础医学 | 19309篇 |
口腔科学 | 1940篇 |
临床医学 | 15756篇 |
内科学 | 34134篇 |
皮肤病学 | 844篇 |
神经病学 | 17608篇 |
特种医学 | 9760篇 |
外国民族医学 | 18篇 |
外科学 | 31609篇 |
综合类 | 6823篇 |
现状与发展 | 4篇 |
一般理论 | 1篇 |
预防医学 | 19811篇 |
眼科学 | 3383篇 |
药学 | 12182篇 |
25篇 | |
中国医学 | 2128篇 |
肿瘤学 | 18714篇 |
出版年
2024年 | 123篇 |
2023年 | 475篇 |
2022年 | 1191篇 |
2021年 | 1350篇 |
2020年 | 1073篇 |
2019年 | 909篇 |
2018年 | 22747篇 |
2017年 | 18109篇 |
2016年 | 20257篇 |
2015年 | 2070篇 |
2014年 | 2226篇 |
2013年 | 1988篇 |
2012年 | 8627篇 |
2011年 | 22863篇 |
2010年 | 19996篇 |
2009年 | 12465篇 |
2008年 | 20705篇 |
2007年 | 22962篇 |
2006年 | 1756篇 |
2005年 | 3408篇 |
2004年 | 4117篇 |
2003年 | 5198篇 |
2002年 | 3114篇 |
2001年 | 837篇 |
2000年 | 1041篇 |
1999年 | 904篇 |
1998年 | 661篇 |
1997年 | 662篇 |
1996年 | 413篇 |
1995年 | 408篇 |
1994年 | 401篇 |
1993年 | 226篇 |
1992年 | 252篇 |
1991年 | 263篇 |
1990年 | 271篇 |
1989年 | 223篇 |
1988年 | 177篇 |
1987年 | 138篇 |
1986年 | 96篇 |
1985年 | 111篇 |
1984年 | 46篇 |
1983年 | 37篇 |
1982年 | 37篇 |
1980年 | 45篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 154 毫秒
71.
红细胞调控白细胞免疫功能新的自然实验研究体系 总被引:4,自引:0,他引:4
目的用血液免疫反应路线图实验体系评估红细胞在白细胞免疫活性中的作用。方法将0·3ml血浆加入0·2ml全血细胞悬液(全血细胞组)或0·2ml白细胞悬液(白细胞组)中,37℃温育1h,用免疫酶联法测定IL-8和IL-12水平,流式细胞仪测定白细胞膜CD4、CD8、CD35和CXCR4表达量。结果全血细胞组IL-8和IL-12水平(分别为5·96±4·26、9·84±2·23ρB·pg-1·ml-1)明显低于白细胞组(分别为15·09±9·86、13·59±3·69ρB·pg-1·ml-1,P<0·05),淋巴细胞CD4、CD35、CXCR4表达量(分别为37·79±12·00、154·66±70·00、34·40±20·45)明显高于白细胞组(分别为18·54±11·32、83·26±35·99、16·69±11·09,P<0.01),粒细胞CD35表达量(603·63±257·64)明显高于白细胞组(384·86±174·16,P<0.01)。成人全血细胞组淋巴细胞和粒细胞CD35和CXCR4表达量明显高于脐血全血细胞组(P<0·05或P<0·01)。结论红细胞是白细胞(包括T淋巴细胞、B淋巴细胞、NK细胞、树突状细胞、粒细胞等)免疫功能的调控者和指导者,脐血红细胞免疫调节功能明显下降;本研究为红细胞免疫调控活性测定提供了新的近似自然的方法。 相似文献
72.
73.
Sergio Barroilhet Adrián Cano-Prous Salvador Cervera-Enguix Maria João Forjaz Francisco Guillén-Grima 《Social psychiatry and psychiatric epidemiology》2009,44(12):1051-1065
Introduction
This paper presents the results of a study on the psychometric properties of an authorized Spanish version of the McMaster Family Assessment Device, a self-report measure of family functioning. 相似文献74.
75.
76.
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77.
Peter Angelos 《World journal of surgery》2009,33(4):609-611
78.
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
79.
80.
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