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   13157篇
  免费   1128篇
  国内免费   29篇
耳鼻咽喉   144篇
儿科学   514篇
妇产科学   373篇
基础医学   1763篇
口腔科学   150篇
临床医学   2035篇
内科学   2441篇
皮肤病学   180篇
神经病学   1234篇
特种医学   210篇
外国民族医学   2篇
外科学   1118篇
综合类   167篇
一般理论   18篇
预防医学   1942篇
眼科学   181篇
药学   754篇
中国医学   9篇
肿瘤学   1079篇
  2024年   20篇
  2023年   144篇
  2022年   171篇
  2021年   380篇
  2020年   291篇
  2019年   433篇
  2018年   445篇
  2017年   389篇
  2016年   359篇
  2015年   392篇
  2014年   500篇
  2013年   759篇
  2012年   1028篇
  2011年   1019篇
  2010年   558篇
  2009年   481篇
  2008年   813篇
  2007年   877篇
  2006年   795篇
  2005年   713篇
  2004年   670篇
  2003年   610篇
  2002年   596篇
  2001年   153篇
  2000年   108篇
  1999年   110篇
  1998年   129篇
  1997年   89篇
  1996年   87篇
  1995年   72篇
  1994年   64篇
  1993年   43篇
  1992年   68篇
  1991年   69篇
  1990年   48篇
  1989年   70篇
  1988年   47篇
  1987年   57篇
  1986年   46篇
  1985年   46篇
  1984年   45篇
  1983年   34篇
  1982年   39篇
  1981年   33篇
  1980年   40篇
  1979年   32篇
  1978年   25篇
  1977年   23篇
  1976年   28篇
  1973年   19篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
The objective of this study was to investigate violent and nonviolent suicidal acts in men and women with severe depression. The records of 98 suicide victims, who had been admitted to the Department of Psychiatry, Lund University Hospital, Sweden between 1956 and 1969, were evaluated and the subjects were monitored up to 1998. The female group displayed a significant linear trend for nonviolent completed suicide after one suicide attempt, and even more significantly, after repeated attempts. A switch from only nonviolent suicide attempts to completed violent suicide was significantly more common in men than in women. These different progressions may contribute to the expected finding that men used violent methods for completed suicide more often than women.  相似文献   
52.
The aims were to investigate: (1) experiences of physical pain in elderly patients with hip fracture; (2) if background variables, confusion, experiences of pain and distress and interventions aimed at reducing pain and distress, functional ability, pain in the ambulance, and type of fracture varied between patients with more intense physical pain and patients with less intense physical pain. The sample included 49 patients, 70 years or older, with hip fracture. Structured instruments were used to interview and observe the patients on four occasions during the hospital stay. The patients’ experiences of physical pain decreased during the hospital stay. Physical pain at rest was lower than pain with movement. Patients who scored physical pain as more intense (group B) during the visit to the hospital had significantly more unfavourable experiences in the sensory, emotional, and existential dimensions the day before discharge from the hospital compared with the patients who scored pain as less intense (group A). The patients in group B perceived the interventions as less favourable than group A. Furthermore, group B had more intense physical pain in the ambulance than the patients in the other group. More patients in group B than in group A had additional health problems.  相似文献   
53.
Background: Noncompliance with instructed saliva sampling times in ambulatory settings can compromise resulting cortisol findings.Purpose and Methods: Here, the impact of noncompliance on the cortisol awakening response (CAR), an established marker for hypothalamic-pituitary-adrenal axis activity, was examined over 3 sampling days in middle- and older-age participants in the Chicago Health, Aging, and Social Relations Study.Results: Noncompliant participants had a significantly lower cortisol rise after awakening (assessed by an awakening sample and a 30-min after awakening sample) on 2 of the 3 sampling days (Day 1, ns; Days 2 & 3, ps<.02). Furthermore, social support measured by the Interpersonal Support Evaluation List correlated negatively with the number of “noncompliant” samples (r=−.19, p<.05), indicating that participants reporting more social support had more “compliant” samples.Conclusion: The results confirm that nonadherence to saliva sampling in ambulatory settings can exert a significant impact on the resulting CAR. Furthermore, the data raise the idea that the extent of nonadherence might be systematically associated with psychosocial factors like social support. For future studies on the relationship between CAR and psychological factors, we therefore recommend controlling for saliva sampling adherence because noncompliance might be systematically associated with the phenomenon being investigated. Funding was provided by the National Institute of Aging Grant No. PO1 AG18911 and the John Templeton Foundation. Brigitte M. Kudielka was supported by grants from the German Research Foundation (DFG grant KU 1401/3-1 and KU 140/4-1).  相似文献   
54.
The January 7, 1988 issue of The New England Journal of Medicine has two interesting articles concerning what might generally be termed euthanasia. The article titled Initiating and Withdrawing Life Support represents a consensus among members of the Stanford University Medical Center Committee on Ethics. Its main authors have written a fine example of applied ethics (1).  相似文献   
55.
56.
To address cancer out-patients' needs for information, a self-servelearning resource center was established at a nearby hotel.This facility provides numberous written and audio-visual cancerinformation materials for out-patients being treated at theUniversity of Texas M.D.Anderson Cancer Center Houston, Texas.Over a three month period, we conductred a consumer profileand assessed consumer satisfaction and use of the learning resuorcecenter. Data were gathered primarily through a self-administeredpatient/family satisfaction questionnaire and through monthlyadministrative records. The primary variables associated withuse of the learning resource center were educational level andhow long one had been a patient at the M.D.Anderson Cancer Center.Respondents who had used the learning resource center also indicateda stronger preference for receiving information about cancerthrough written materials than those who had not used the center.Users’ degree of satisfaction with the learning resourcecenter was generally high. The case study presented here offersrecommendations for the practitioner regarding the establishmentand evaluation of a learning resource center for cancer out-patientsand addresses these issues in a unique program setting.  相似文献   
57.
p = 0.17) and the average number of antihypertensive medications decreased to 1.9 (p= 0.001). During the median follow-up of 33 months, 10 patients died, mainly from cardiac causes. Our experience indicates that the splenic and hepatic arteries provide useful alternatives to renal revascularization in selected circumstances with an acceptable rate of perioperative mortality and morbidity. The expected long-term survival in this group of patients is low.  相似文献   
58.
Background: Controversy exists as to the risk for postoperative apnea in former preterm infants. The conclusions of published studies are limited by the small number of patients.

Methods: The original data from eight prospective studies were subject to a combined analysis. Only patients having inguinal herniorrhaphy under general anesthesia were included; patients receiving caffeine, regional anesthesia, or undergoing other surgical procedures were excluded. A uniform definition for apnea was used for all patients. Eleven risk factors were examined: gestational age, postconceptual age, birth weight, history of respiratory distress syndrome, bronchopulmonary dysplasia, neonatal apnea, necrotizing enterocolitis, ongoing apnea, anemia, and use of opioids or nondepolarizing muscle relaxants.

Results: Two hundred fifty-five of 384 patients from eight studies at four institutions fulfilled study criteria. There was significant variation in apnea rates and the location of apnea (recovery room and postrecovery room) between institutions (P < 0.001). There was considerable variation in the duration and type of monitoring, definitions of apnea, and availability of historical information. The incidence of detected apnea was greater when continuous recording devices were used compared to standard impedance pneumography with alarms or nursing observations. Despite these limitations, it was determined that: (1) apnea was strongly and inversely related to both gestational age (P = 0.0005) and postconceptual age (P < 0.0001); (2) an associated risk factor was continuing apnea at home; (3) small-for-gestational-age infants seemed to be somewhat protected from apnea compared to appropriate- and large-for-gestational-age infants; (4) anemia was a significant risk factor, particularly for patients > 43 weeks' postconceptual age; (5) a relationship to apnea with history of necrotizing enterocolitis, neonatal apnea, respiratory distress syndrome, bronchopulmonary dysplasia, or operative use of opioids and/or muscle relaxants could not be demonstrated.  相似文献   

59.
This article explores the relationship of ethics to validity in hermeneutic phenomenological inquiry. First, the authors present a brief overview of the various discourses on validity in qualitative research that have been variously applied to hermeneutic phenomenological inquiry. Next, they examine how relational ethics is a presence to bear within this form of inquiry. Finally, they offer a set of ethical reflections to help the researcher engage in a process of ethical questioning during each step of the research process.  相似文献   
60.
This paper presents the results of a qualitative study conducted by midwife researchers into women's experience of new motherhood. Data were collected using focus groups involving 55 first-time mothers and analysed using grounded theory method. The analysis produced six categories: 'realizing', 'unready', 'drained', 'aloneness', 'loss' and 'working it out'. The core category, 'becoming a mother', integrates all other categories and encapsulates the process of change experienced by women. Also explained are factors mediating the often distressing experience of becoming a mother. The analysis provides a conceptualization of early motherhood enabling the development of strategies for midwives, nurses and others helping women negotiate this challenge.  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