全文获取类型
收费全文 | 7257篇 |
免费 | 539篇 |
国内免费 | 15篇 |
学科分类
医药卫生 | 7811篇 |
出版年
2023年 | 57篇 |
2022年 | 28篇 |
2021年 | 115篇 |
2020年 | 89篇 |
2019年 | 129篇 |
2018年 | 266篇 |
2017年 | 183篇 |
2016年 | 185篇 |
2015年 | 228篇 |
2014年 | 229篇 |
2013年 | 306篇 |
2012年 | 596篇 |
2011年 | 634篇 |
2010年 | 292篇 |
2009年 | 248篇 |
2008年 | 493篇 |
2007年 | 635篇 |
2006年 | 550篇 |
2005年 | 569篇 |
2004年 | 465篇 |
2003年 | 458篇 |
2002年 | 388篇 |
2001年 | 61篇 |
2000年 | 68篇 |
1999年 | 65篇 |
1998年 | 23篇 |
1997年 | 17篇 |
1996年 | 14篇 |
1995年 | 13篇 |
1994年 | 13篇 |
1993年 | 10篇 |
1992年 | 31篇 |
1991年 | 36篇 |
1990年 | 23篇 |
1989年 | 21篇 |
1988年 | 20篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 11篇 |
1984年 | 12篇 |
1983年 | 14篇 |
1982年 | 9篇 |
1975年 | 10篇 |
1974年 | 9篇 |
1973年 | 14篇 |
1972年 | 15篇 |
1971年 | 8篇 |
1969年 | 12篇 |
1968年 | 11篇 |
1967年 | 14篇 |
排序方式: 共有7811条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
Biological width formation to immediate implants placed at different level in relation to the crestal bone: an experimental study in dogs 下载免费PDF全文
105.
106.
107.
Background: Cannabis is the most widely used illicit drug in the United States and Europe. In recent years, a range of new substances with cannabis-like effects—known as synthetic cannabinoids (SCs)—have suddenly burst on the drug scene. However, there is limited information about the clinical hazards linked to the use of these emerging substances. This review summarizes the literature to date relating the health effects of SCs. Method: A systematic literature review of original case studies was performed using PubMed and Web of Science (January 1980–July 2015). Only articles in which a drug screening was reported were included in this review. Results: Forty-six articles meeting the inclusion criteria were included in this review, reporting data on 114 patients who went to hospital emergency departments after exposure to SCs. The majority of patients were adolescent or young adult males (14–25 years; 24.5 ± 10.1 years). The most common route of administration was smoking. The SCs most involved were John William Huffman (JWH) derivatives, followed by XRL-11, ADB-PINACA, AM-2201, MAM-2201, and 5F-PB-22. This analysis showed that the use of these substances may cause minor and moderate side effects similar to those of cannabis intoxication, including tachycardia, nausea, somnolence, hallucinations, paranoia, xerostomia, and injected conjunctivae among others. However, atypical cannabis intoxication effects and worse complications (such as renal injuries, aggressiveness, cerebral ischemia, myocardial infarction, etc.) were also observed, which led to a significant morbidity were also observed. Some SCs were highlighted as being involved in 24 cases of deaths. Conclusions: In this review, the nature and frequency of the signs and symptoms of SC poisoning were estimated in order to inform health professionals about the health risks of these new and emerging substances. 相似文献
108.
109.
Jérémy Besnard Philippe Allain Ghislaine Aubin Valérie Chauviré Frédérique Etcharry-Bouyx Didier Le Gall 《Journal of clinical and experimental neuropsychology》2014,36(1):88-109
Introduction: A. R. Luria was the first author to hypothesize that executive dysfunction can lead to specific deficits in arithmetic problem solving, showing that patients’ performance depends on the structure of the tasks. Cummings (1995. Anatomic and behavioral aspects of frontal-subcortical circuits. Annals of the New York Academy of Sciences, 15, 1–13) proposed the term “environmental dependency” to define such behavioral disorders triggered by the characteristics of the test and pointed out also the role of executive impairments. Few studies compare executive functioning and problem solving in brain-damaged patients, and none have examined the question from this point of view. Thus, the main aim of the present paper was to study the relationship between environmental dependency and executive functions. Method: Fifty neurological patients with frontal, subcortical, and posterior brain lesions were compared to 45 matched healthy controls and were divided into two groups (dysexecutive/nondysexecutive) according to their performances on executive tasks. Then, we confronted the results of the two groups on an experimental protocol designed in accordance with Luria’s proposals. We made also comparisons between groups on the basis of lesion location. Results: Our findings indicate a high association between executive functions and environmental dependency, showing that dysexecutive patients’ performances were dependent on task demands. In addition, a specific frontal behavior not associated with executive functions and characterized by the solving of insoluble problems was highlighted. Conclusion: The discussion focused on the interest to take into account the methodological and clinical contributions of environmental dependency. Based on our findings and theoretical arguments, we highlight the need to fractionate this concept. 相似文献
110.
Zsolt Baranyai Valéria Jósa Ambrus Tóth Zsuzsanna Szilasi Balazs Tihanyi Attila Zaránd 《Platelets》2016,27(4):269-275
It has been demonstrated recently in several solid tumors that thrombocytosis at diagnosis may correlate with tumor invasion, metastatic progression and worse outcome. Several details of the pathomechanism of the relationship of thrombocytosis and cancer have been elucidated; however, the complete process is not clearly understood. Several hypotheses have been proposed. Recently, it was suggested that in ovarian cancer elevated IL-6 production by the tumor may induce increased megakaryopoiesis via hepatic thrombopoietin production leading to thrombocytosis. The importance of the prognostic power of elevated platelet count is still debated in gastrointestinal cancer. The aims of this review were to evaluate the prognostic significance of thrombocytosis in gastrointestinal tumors, to see whether clinical practice confirmed the hypotheses and to reveal the causes of the inconsistent findings. 相似文献