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   2578篇
  免费   142篇
  国内免费   52篇
耳鼻咽喉   24篇
儿科学   121篇
妇产科学   135篇
基础医学   334篇
口腔科学   58篇
临床医学   214篇
内科学   565篇
皮肤病学   66篇
神经病学   166篇
特种医学   168篇
外科学   345篇
综合类   22篇
一般理论   2篇
预防医学   169篇
眼科学   35篇
药学   145篇
中国医学   14篇
肿瘤学   189篇
  2023年   10篇
  2022年   14篇
  2021年   54篇
  2020年   44篇
  2019年   51篇
  2018年   82篇
  2017年   48篇
  2016年   43篇
  2015年   44篇
  2014年   72篇
  2013年   88篇
  2012年   141篇
  2011年   129篇
  2010年   105篇
  2009年   109篇
  2008年   121篇
  2007年   183篇
  2006年   116篇
  2005年   94篇
  2004年   103篇
  2003年   98篇
  2002年   91篇
  2001年   60篇
  2000年   81篇
  1999年   60篇
  1998年   56篇
  1997年   37篇
  1996年   61篇
  1995年   39篇
  1994年   29篇
  1993年   26篇
  1992年   42篇
  1991年   39篇
  1990年   52篇
  1989年   55篇
  1988年   53篇
  1987年   37篇
  1986年   42篇
  1985年   21篇
  1984年   12篇
  1983年   15篇
  1982年   12篇
  1981年   9篇
  1980年   12篇
  1979年   17篇
  1978年   15篇
  1977年   16篇
  1976年   8篇
  1975年   8篇
  1974年   6篇
排序方式: 共有2772条查询结果,搜索用时 15 毫秒
1.
2.
The Latin American population has a double way of immigration, one toward the United States by proximity and another toward Spain by sociocultural affinity. This population increase is affecting organ donation and transplantation in receiving countries.

Objective

To analyze the brain death (BD) concept knowledge in the Dominican Republic immigrant population in Florida (United States) and Spain.

Method

Population under study: Population born in the Dominican Republic, resident in Florida (United States) and in Spain. Inclusion criteria: Population older than 15 years stratified by age and sex. Assessment instrument: Donation attitude questionnaire PCID-DTO-Ríos. Fieldwork: Random selection based on stratification. Immigration support association collaboration in Florida and Spain was needed to locate potential respondents. Completion was anonymous and self-administered, with verbal consent.

Results

A total of 123 respondents, 57 residents in Spain and 66 in Florida, have been included in the study. The 27% (n = 33) of the respondents knowledgeable of the BD concept consider it the death of an individual. Of the remainder, 52% (n = 64) do not know about it, and the remaining 21% (n = 26) believe it does not mean the death of a patient. No differences were observed regarding migration countries (P > .05). There was no association of the BD concept with other psychosocial factors analyzed or with the attitude toward organ donation.

Conclusions

Knowledge of the BD concept among the Dominican immigrant population is similar in Spain and Florida, and, unlike most studies, there is no objective association with the attitude toward organ donation.  相似文献   
3.
4.
Pituitary metastases of solid tumours are infrequent, specially as a first manifestation. When they happen, they are usually due to breast or lung cancer and are asymptomatic or produce diabetes insipidus. It is very strange that they produce hormonal deficiency. We present a case report of a bronchogenic adenocarcinoma in a 65-year-old man which began with panhypopituitarism, diabetes insipidus and visual alterations. Magnetic resonance imaging revealed a large sellar mass, with clivus infiltration and invading the right cavernous sinus. The biopsy result was adenocarcinoma metastases from lung cancer.  相似文献   
5.
E Garrido  G R Fahs 《Neurosurgery》1990,26(3):540-542
The authors report a case of cortical vein and sagittal sinus thrombosis after a transcallosal removal of a colloid cyst of the third ventricle. Thirty-six hours after the operation, the patient developed focal seizures; after progressive deterioration, he died on the sixth postoperative day. At the autopsy, a venous hemorrhagic infarct in the right frontoparietal area and fresh thrombus occluding the sagittal sinus and cortical veins were found. The mechanism of cortical vein and sinus thrombosis subsequent to this procedure is discussed, and suggestions are made to prevent this serious complication.  相似文献   
6.
The neuropeptides neurotensin and neuromedin N (from 10−12 M to 10−9 M) have been showed in this study to stimulate significantly in vitro several steps of the phagocytic process: adherence to substrate, chemotaxis, ingestion of inert particles (latex beads) and production of superoxide anion measured by nitroblue tetrazolium reduction in resting peritoneal macrophages from BALB/c mice. A dose-response relationship was observed, with a maximal stimulation of the phagocytic process at 10−11 M. The two neuropeptides induced no change of intracellular cyclic AMP in murine macrophages. Moreover, adherence and chemotaxis decreased significantly in the presence of EGTA (1 mM), a chelator of extracellular Ca2+, or ryanodine (0.5 mM), a blocker of a Ca2+-gated channel from the endoplasmic reticulum, in both controls and samples with the addition of neurotensin or neuromedin N. These results suggest that there is no relation between the cAMP messenger system and the phagocytic process stimulation in murine peritoneal macrophages by neurotensin or neuromedin N. In addition, the results observed with EGTA and ryanodine could indicate that these two neuropeptides produce their effects through an increase of intracellular Ca2+ concentration.  相似文献   
7.
8.
9.
The monoclonal antibody GR7A4 was produced against a human lymphoblastic leukemia (ALL-B). Biochemical characterization of GR7A4 was carried out with Raji cells in SDS-PAGE studies. GR7A4 precipitated a 43 kd molecule. The tissue distribution and molecular weight were similar to the T10 antigen. Modulation and capping of GR7A4 antigen reduced its binding ability to cells with either GR7A4 or OKT10. However, the cell surface distribution pattern observed was somewhat different from other similar monoclonal antibodies. Thus GR7A4 reacted greatly with pre-B-cell lines, Burkitt cell lines, EBV cell lines and activated PHA, ConA and PWM lymphocytes, however reactivity with leukemic cells was very limited. The kinetics of appearance of GR7A4 antigen on PWM blasts show that this molecule seems to represent an intermediate stage in lymphocytic activation. The differences in comparison with other similar MAbs are discussed and correlated with the peculiar discontinous pattern of appearance of this antigen.  相似文献   
10.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  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