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   8553篇
  免费   649篇
  国内免费   19篇
耳鼻咽喉   33篇
儿科学   262篇
妇产科学   298篇
基础医学   1041篇
口腔科学   113篇
临床医学   1531篇
内科学   1304篇
皮肤病学   188篇
神经病学   875篇
特种医学   296篇
外科学   886篇
综合类   146篇
一般理论   39篇
预防医学   970篇
眼科学   176篇
药学   500篇
  1篇
中国医学   4篇
肿瘤学   558篇
  2023年   45篇
  2022年   93篇
  2021年   179篇
  2020年   101篇
  2019年   186篇
  2018年   213篇
  2017年   152篇
  2016年   157篇
  2015年   204篇
  2014年   289篇
  2013年   387篇
  2012年   515篇
  2011年   570篇
  2010年   337篇
  2009年   295篇
  2008年   421篇
  2007年   528篇
  2006年   490篇
  2005年   495篇
  2004年   467篇
  2003年   418篇
  2002年   420篇
  2001年   127篇
  2000年   103篇
  1999年   115篇
  1998年   137篇
  1997年   132篇
  1996年   108篇
  1995年   81篇
  1994年   78篇
  1993年   68篇
  1992年   88篇
  1991年   95篇
  1990年   89篇
  1989年   88篇
  1988年   77篇
  1987年   69篇
  1986年   80篇
  1985年   71篇
  1984年   76篇
  1983年   66篇
  1982年   55篇
  1981年   49篇
  1980年   45篇
  1979年   43篇
  1978年   38篇
  1977年   28篇
  1976年   26篇
  1975年   25篇
  1974年   22篇
排序方式: 共有9221条查询结果,搜索用时 28 毫秒
51.
Background. Paragangliomas of the head and neck are slow-growing tumors that originate from neural crest cells. Between 7% and 9% of these tumors have a familial occurrence. The suspected gene for familial paragangliomas (FP) is transmitted with an autosomal dominant mode of inheritance with incomplete penetrance, and appears to exhibit genomic imprinting. It has been demonstrated by family studies that individuals who inherit the gene(s) from their father will develop the disease. Through linkage analysis, the gene(s) for FP has been postulated to be located on the long arm of chromosome 11. The discovery of many different genes has been elucidated through the cytogenetic analysis of affected individuals who carry specific chromosome aberrations. This project was designed to look for chromosome abnormalities in several second-generation family members to further assist in the localization of the gene(s) for FP. Methods. This study involved the cytogenetic evaluation of lymphocytes, fibroblasts, and tumor cells of several second-generation family members from a three-generation family with FP of the head and neck to look for chromosome abnormalities generally, and for abnormalities of chromosome 11 specifically. Standard cytogenetic techniques were used for lymphocyte and fibroblast cultures. Tumor cells were cultured in a collagen matrix with F12 medium supplemented with 3% L-glutamine and 10% fetal calf serum. Results. There were no detectable abnormalities of chromosome 11 in any of the cells. However, nonrandom abnormalities of chromosomes 5 and 7 were seen in some of the tumor cells of one FP patient. To our knowledge, this is the first article which demonstrated the ability to successfully culture FP of the head and neck. © 1995 Jons Wiley & Sons, Inc.  相似文献   
52.
The population is aging, and advanced age is commonly identified as a risk factor for delayed wound healing. Therefore, it is important for WOC nurses to be knowledgeable about how aging affects the wound healing and repair process, and strategies they can use to promote healing in the elderly population. Impaired wound healing in the aged is due partly to comorbidities common among the elderly, but evidence also suggests that inherent differences in cellular structure and function may impair tissue repair and regeneration as well. This article will address the effect of aging on wound healing, with a particular focus on processes of cellular senescence and related factors hypothesized to result in slowed or impaired wound healing in the elderly.  相似文献   
53.
Personal Digital Assistants (PDAs) are a readily accessible source of information to aid in the delivery of patient care. A pilot group of five Family Nurse Practitioner students used PDAs to organize data and access information relevant to patient care. Utilization of the PDAs in the clinical setting provided practice guidelines, textbook information and protocols that were readily accessible. The PDA made it possible for students to utilize preexisting knowledge with additional learning resources. The PDAs were purchased with funds provided from a United States Department of Health and Human Services, Health Resources and Services Administration (HRSA) grant.  相似文献   
54.
Nosocomial pressure ulcers (PU) occur in approximately 12% of all hospitalized patients. The risk can be determined by a variety of intrinsic and extrinsic factors. As a first line of defense against nosocomial PU, we use the Braden Scale to determine the potential risk of PU development during hospitalization. Once risk was identified, our standard was to implement an individualized plan of care. However, consistent implementation of PU preventative measures was lacking. As a result, a process improvement project was developed and implemented. The purpose of this process improvement project was to increase communication about and awareness of the need to vigorously intervene and document whenever there is risk of, or development of, a nosocomial PU. By initiating consistent use of a PU Tracking Form, developing unit-based wound champions that serve as experts in ulcer prevention, and creating an individual case analysis process, PU prevention and tracking was institutionalized. Results indicate that our nosocomial PU rate has declined from 7% to 4%.  相似文献   
55.
56.
Soutter  J; Eccles  MP; Newton  J 《Family practice》1996,13(2):152-155
BACKGROUND: Partnerships have been investigated in different professions,but other than identifying problems, little work has been carriedout on general practice. OBJECTIVE: The aim of this present study was to develop methods for studyingpartnerships in general practice. METHOD: A tripartite methodological approach was used, with questionnairesadapted from other instruments in use in other professions,followed by an individual interview with each partner, and non-participantobservation at a partnership meeting. Results for one case-studypartnership are given. RESULTS: There were no major differences between the partners on alldimensions measured; the minor differences indicated by theresults of the questionnaires were corroborated by the partnerinterviews and observations. CONCLUSIONS: We conclude that the use of such techniques could provide supportto partnerships going through significant periods of change. Keywords. General practice, interview, observation, partnerships, questionnaire.  相似文献   
57.
58.
Abdominal trauma: use of oral contrast material for CT is safe   总被引:2,自引:0,他引:2  
  相似文献   
59.
Six healthy male subjects were studied to determine whether the reduced plasma cortisol response to methylphenidate observed in depressed patients could be reproduced in normal subjects by pretreatment with physostigmine. Indeed, physostigmine was found to mimic this effect. The finding raises the possibility that increased cholinergic rather than decreased adrenergic activity could explain the blunted cortisol response to stimulants reported in depressed patients. Physostigmine also enhanced the growth hormone rise and prolactin decline, and limited the increase in heart rate following methylphenidate administration.  相似文献   
60.
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