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   1341395篇
  免费   112711篇
  国内免费   6415篇
耳鼻咽喉   16742篇
儿科学   43079篇
妇产科学   36632篇
基础医学   184006篇
口腔科学   36404篇
临床医学   120938篇
内科学   278980篇
皮肤病学   31941篇
神经病学   110707篇
特种医学   55616篇
外国民族医学   274篇
外科学   210729篇
综合类   31704篇
现状与发展   2篇
一般理论   414篇
预防医学   106932篇
眼科学   28152篇
药学   93977篇
  6篇
中国医学   2283篇
肿瘤学   71003篇
  2018年   13454篇
  2017年   10717篇
  2016年   12900篇
  2015年   14382篇
  2014年   20066篇
  2013年   29876篇
  2012年   36461篇
  2011年   39124篇
  2010年   24484篇
  2009年   24011篇
  2008年   36533篇
  2007年   38946篇
  2006年   40084篇
  2005年   38672篇
  2004年   36861篇
  2003年   35935篇
  2002年   33940篇
  2001年   66114篇
  2000年   67978篇
  1999年   56632篇
  1998年   16738篇
  1997年   15036篇
  1996年   16034篇
  1995年   16247篇
  1994年   15108篇
  1993年   14164篇
  1992年   47109篇
  1991年   45762篇
  1990年   43989篇
  1989年   41843篇
  1988年   38778篇
  1987年   38090篇
  1986年   35878篇
  1985年   34657篇
  1984年   26366篇
  1983年   22113篇
  1982年   13852篇
  1981年   12449篇
  1980年   11725篇
  1979年   23554篇
  1978年   17073篇
  1977年   14388篇
  1976年   13187篇
  1975年   13728篇
  1974年   16100篇
  1973年   15398篇
  1972年   14175篇
  1971年   13045篇
  1970年   11885篇
  1969年   11111篇
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
101.
102.
103.
Abstract Chorea is a rare complication of polycythaemia vera. Polycythaemic chorea occurs predominantly in females and usually in generalised form. We present a 66-year-old woman with acute onset hemichorea-ballism with no vascular pathology in the basal ganglia region. A clear relationship was observed between the onset of chorea and worsening of haematological parameters in the patient. After repeated phlebotomies the patient's clinical status was improved. Polycythaemic chorea must be considered, especially in the elderly, as early diagnosis leads to effective treatment and prevention of complications.  相似文献   
104.
105.
For many parents stopping life-sustaining medical treatment on their dying infant is psychologically impossible. Dostoevsky's insights into human behavior, particularly the fact that individuals do not want the anxiety and guilt associated with responsibility for making difficult decisions, might change the way physicians approach parents for permission to withdraw life-prolonging medical interventions on dying infants.  相似文献   
106.
Four clinical trials of porcine islet transplantation have been reported, and there are verbal reports that clinical trials on much larger scales are continuing in centers in China and Russia. The four reported trials are briefly reviewed and, in the light of the present status of experimental islet xenotransplantation, consideration is given to whether such trials are currently justified. The Ethics Committee of the International Xenotransplantation Association has (1) emphasized the need for encouraging studies in non-human primates before clinical trials should be undertaken, (2) mandatory monitoring for the transfer of porcine microorganisms, and (3) careful regulation and oversight by recognized bodies. Other aspects of the topic, such as the need for informed consent, are briefly discussed. We conclude that, at the present time, more data documenting convincing efficacy, focused on clinically applicable immunosuppressive regimens, are needed to justify the initiation of closely monitored clinical trials. A clinical trial may then be justified even though the potential risk to the patients, and possibly for society, will not be zero.  相似文献   
107.
108.
Summary: The mosaic (Atp7a mo-ms ) is an X-linked, lethal mutation in mice. In mosaic mutant males, many clinical features characteristic of defective copper metabolism have been observed and they die at the age of 15 days, exhibiting strongsimilarities to the brindled and macular mutants. About 4% of the mutant males live to sexual maturity and some of them are fertile. In this paper, alterationsin the structure of the kidney from adult mutants are described. Owing to an inherited defect of efflux, copper is accumulated in the kidney of the mutants up to a toxic level and this leads to severe damage of the renal cortex. Pathological changes in the kidney mostly affected the structure of the renal corpuscle and renaltubules.  相似文献   
109.
110.
BACKGROUND: The relationship between the circumstances and severity of closed head injury (CHI) and the clinical and imaging features of cranial nerve 3, 4, and 6 palsies has not been rigorously addressed in a large study. METHODS: Retrospective chart review of 210 consecutive patients with CHI examined at a single tertiary care center from 1987 to 2002. Patients were located by searching the ophthalmology inpatient consultation and neuro-ophthalmology outpatient databases and hospital emergency room billing codes for a diagnosis of traumatic 3, 4, or 6 cranial nerve palsy (Cranial Nerve Injury Group) and a diagnosis of CHI without traumatic 3, 4, or 6 nerve palsy (Control Group). The Cranial Nerve Injury Group was then subdivided into two groups: those with injuries to an individual cranial nerve and those with multiple (including bilateral) cranial nerve injuries. Comparisons between groups were based on age, gender, type of accident, Glasgow Coma Scale (GCS), documented loss of consciousness (LOC), type of ocular injury, presence of systemic injury, need for rehabilitation, physical therapy and cognitive scores, and imaging features. RESULTS: The Cranial Nerve Injury Group had a significantly higher severity of head injury, more CT abnormalities, and worse short-term neurologic outcomes as compared with the Control Group. These trends were also found when each cranial nerve injury subgroup was compared with the Control Group. Those with cranial nerve 3 palsy had the most severe head injury; those with cranial nerve 4 palsy had an intermediate level of head injury; and those with cranial nerve 6 palsy had the lowest level of head injury. There were no consistent associations between the location of the imaging abnormalities and which cranial nerve was damaged. CONCLUSIONS: CHI with palsy of an ocular motor nerve was more severe than CHI without ocular motor nerve palsy, as measured by the GCS, intracranial and skull imaging abnormalities, and a greater frequency of inpatient rehabilitation. Palsy of cranial nerve 3 was associated with relatively more severe CHI than was palsy of cranial nerves 4 or 6. The location of the imaging abnormalities did not correlate with a particular cranial nerve injury.  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