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   4225551篇
  免费   344905篇
  国内免费   15526篇
耳鼻咽喉   58242篇
儿科学   132733篇
妇产科学   111987篇
基础医学   648332篇
口腔科学   118785篇
临床医学   381771篇
内科学   757210篇
皮肤病学   106344篇
神经病学   352799篇
特种医学   166516篇
外国民族医学   425篇
外科学   650693篇
综合类   129103篇
现状与发展   25篇
一般理论   2501篇
预防医学   346697篇
眼科学   100504篇
药学   298505篇
  21篇
中国医学   12370篇
肿瘤学   210419篇
  2021年   55908篇
  2020年   35612篇
  2019年   58751篇
  2018年   73805篇
  2017年   56068篇
  2016年   62163篇
  2015年   75499篇
  2014年   109877篇
  2013年   175464篇
  2012年   117495篇
  2011年   121232篇
  2010年   124265篇
  2009年   126191篇
  2008年   107332篇
  2007年   114149篇
  2006年   122625篇
  2005年   117457篇
  2004年   119101篇
  2003年   108844篇
  2002年   97916篇
  2001年   155913篇
  2000年   150568篇
  1999年   139154篇
  1998年   71126篇
  1997年   67081篇
  1996年   64839篇
  1995年   60324篇
  1994年   54450篇
  1993年   50658篇
  1992年   100989篇
  1991年   96808篇
  1990年   92659篇
  1989年   90570篇
  1988年   83797篇
  1987年   81823篇
  1986年   77590篇
  1985年   76192篇
  1984年   64589篇
  1983年   57584篇
  1982年   46732篇
  1981年   43581篇
  1980年   40951篇
  1979年   55543篇
  1978年   45131篇
  1977年   40335篇
  1976年   37046篇
  1975年   36829篇
  1974年   40765篇
  1973年   39275篇
  1972年   36974篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
993.
994.
995.
Inbred mouse strains are the most widely used mammalian model organism in biomedical research owing to ease of genetic manipulation and short lifespan; however, each inbred strain possesses a unique repertoire of deleterious homozygous alleles that can make a specific strain more susceptible to a particular disease. In the current study, we report dystrophic cardiac calcinosis (DCC) in C.B‐17 SCID male mice at 10 weeks of age with no significant change in cardiac function. Acquisition of DCC was characterized by myocardial injury, fibrosis, calcification, and necrosis of the tissue. At 10 weeks of age, 38% of the C.B‐17 SCID mice from two different commercial colonies exhibited significant calcinosis on the ventricular epicardium, predominantly on the right ventricle. The frequency of calcinosis was more than 50% for mice obtained from Taconic's Cambridge City colony and 25% for mice obtained from Taconic's German Town colony. Interestingly, the DCC phenotype did not affect cardiac function at 10 weeks of age. No differences in echocardiography or electrocardiography were observed between the calcinotic and non‐calcinotic mice from either colony. Our findings suggest that C.B‐17 SCID mice exhibit DCC as early as 10 weeks of age with no significant impact on cardiac function. This strain of mice should be cautiously considered for the study of cardiac physiology.  相似文献   
996.

Objective

To discover the experiences of end-of-life patients attended by the emergency services, through the discourse of the family caregivers who accompanied the family member in this care transit.

Method

A qualitative approach study, based on the paradigm of hermeneutical phenomenology. In total, 81 family caregivers participated. The techniques used were the in-depth interview and the discussion group, with a total of 5 discussion groups and 41 interviews. The period of data collection was carried out between January 2013 and June 2014.

Results

In the network of discourses obtained with respect to “Urgent Care”, all the codes were grouped in relation to a single argumentative line: deficiencies in urgent care. Among them, we found different dimensions that are established depending on the different times of care, or the different determinant aspects of these deficiencies: disorganization of the care received, lack of experience of the professionals in emergencies, application of general protocols in the emergency services, inadequate care in the treatment received, delays in emergency care.

Conclusions

In general, we highlight the dissatisfaction of the family members with respect to the care received from the emergency services. The needs of these types of situation are not covered from these services and are of low quality. Therefore, it is necessary to reorient the care protocols for these patients.  相似文献   
997.
998.

Background

A history of childhood maltreatment and psychopathology are common in adults with obesity.

Objectives

To report childhood maltreatment and to evaluate associations between severity and type of childhood maltreatment and lifetime history of psychopathology among adults with severe obesity awaiting bariatric surgery.

Setting

Four clinical centers of the Longitudinal Assessment of Bariatric Surgery Research Consortium.

Methods

The Childhood Trauma Questionnaire, which assesses presence/severity (i.e., none, mild, moderate, severe) of physical abuse, mental abuse, physical neglect, mental neglect, and sexual abuse, was completed by 302 female and 66 male bariatric surgery patients. Presurgery lifetime history of psychopathology and suicidal ideation/behavior were assessed with the Structured Clinical Interview for DSM-IV and the Suicidal Behavioral Questionnaire-Revised, respectively. Presurgery lifetime history of antidepressant use was self-reported.

Results

Two thirds (66.6%) of females and 47.0% of males reported at least 1 form of childhood trauma; 42.4% and 24.2%, respectively, at greater than or equal to moderate severity. Among women, presence/greater severity of childhood mental or physical abuse or neglect was associated with a higher risk of history of psychopathology (i.e., major depressive disorder, posttraumatic stress disorder, other anxiety disorder, alcohol use disorder, binge eating disorder), suicidal ideation/behavior and antidepressant use (P for all ≤ .02). These associations were independent of age, race, education, body mass index, and childhood sexual abuse. Childhood sexual abuse was independently associated with a history of suicidal ideation/behavior and antidepressant use only (P for both ≤ .05). Statistical power was limited to evaluate these associations among men.

Conclusion

Among women with obesity, presence/severity of childhood trauma was positively associated with relatively common psychiatric disorders.  相似文献   
999.
1000.
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