全文获取类型
收费全文 | 898篇 |
免费 | 69篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 28篇 |
妇产科学 | 11篇 |
基础医学 | 59篇 |
口腔科学 | 6篇 |
临床医学 | 164篇 |
内科学 | 139篇 |
皮肤病学 | 10篇 |
神经病学 | 73篇 |
特种医学 | 9篇 |
外科学 | 93篇 |
综合类 | 23篇 |
一般理论 | 2篇 |
预防医学 | 302篇 |
眼科学 | 4篇 |
药学 | 22篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 17篇 |
出版年
2023年 | 27篇 |
2022年 | 32篇 |
2021年 | 51篇 |
2020年 | 43篇 |
2019年 | 42篇 |
2018年 | 41篇 |
2017年 | 37篇 |
2016年 | 34篇 |
2015年 | 45篇 |
2014年 | 67篇 |
2013年 | 81篇 |
2012年 | 50篇 |
2011年 | 41篇 |
2010年 | 33篇 |
2009年 | 40篇 |
2008年 | 50篇 |
2007年 | 41篇 |
2006年 | 38篇 |
2005年 | 22篇 |
2004年 | 23篇 |
2003年 | 36篇 |
2002年 | 14篇 |
2001年 | 14篇 |
2000年 | 16篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 8篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
排序方式: 共有967条查询结果,搜索用时 15 毫秒
51.
52.
53.
Linda Mason Cliff Cunningham 《Journal of Applied Research in Intellectual Disabilities》2009,22(3):287-297
Background Prevalence of pre‐menstrual syndrome (PMS) may be higher in women with Down syndrome due to syndrome specific characteristics in biochemistry, psychopathology and lifestyle. Recognition of PMS may be difficult for women with intellectual disabilities and their carers. Method A daily diary, used to diagnose PMS with typical women, was adapted. Following its validation, the diary was completed by 33 women with Down syndrome, then adapted, and completed by a further 32 women with Down syndrome/carers. Results PMS was diagnosed in 18–20% although a higher proportion (54%) of mothers thought their daughter had PMS. Conclusions The hypotheses that PMS would be higher or go unrecognized in women with Down syndrome was not supported. The diary was well received by both carers and women with Down syndrome and could be an educative, clinical and research tool for use with any woman with intellectual disability. 相似文献
54.
China has one of the largest bodies of college students who face growing academic stress that influences their well-being. Using a daily diary method in a group of Chinese college students (n = 139, mean age = 19.50 years, 27% males) who reported their daily positive and negative emotion consecutively for two weeks, this study investigated the dynamic relations between daily academic stress, leisure activities engagement, and emotion, and further examined the moderation of sex on these links. The results showed that at both between- and within-person level, academic stress was positively associated with negative emotion, and leisure activities engagement was positively associated with positive emotion. The association between leisure activities engagement and positive emotion were stronger among female students than among male students. These results suggest that effectively reducing academic stress and actively engaging in leisure activities are both important in promoting and enhancing daily emotional well-being. 相似文献
55.
Objective.— The objective of this study was to compare the relationship between repeated momentary reports of stress and headaches in female adolescents with varying degrees of headache frequency. Background.— Headaches are the most common form of pain reported by adolescents affecting more than a third of all adolescents. High levels of stress during adolescence may predispose an adolescent to experience headaches in adulthood. Randomized, momentary data collection of stress and headaches provides the most accurate data regarding the adolescent experience of these variables. Methods.— The research methodology, ecological momentary assessment, is a valid approach to better understand the relationship between stress and headaches in adolescence. Data were obtained by each participant's use of an electronic diary (ED), which captured repeated momentary reports of perceived stress, head pain, and stress‐related symptoms in female adolescents with varying degrees of recurrent headache. Seven times per day for the 21‐day study period, teen girls responded to ED questions about their current stress levels, head pain, and stress‐related symptoms. Based on participants' momentary reports of headaches, Low Headache, Moderate Headache, and Chronic Headache groups were created. General estimating equation models were used to analyze the relationship between momentary variables as well as the lag effect between stress and head pain. Results.— Thirty‐one participants, aged 14‐18 years, completed 2841 randomized ED reports and reported 674 occurrences of headache. The Chronic Headache and Moderate Headache groups reported significantly increased levels of stress, head pain, and headaches. The relationship between momentary stress and head pain was significantly strong both within and across participants. The strength of this relationship increased with increased headache activity. A significant lag effect was found between stress and headaches; however, the effect of depression as a moderator of the stress and headache relationship remains unclear. Conclusion.— Perceived stress and head pain was highly correlated in these female adolescents. Given the large population of teens affected by headaches, a plausible next step would be to validate these results in other samples and to determine methods with which to identify teens who may be at risk for a pattern of increasing stress and headaches. 相似文献
56.
Philip L. Henneman Jane L. Garb Geoffrey A. Capraro Haiping Li Howard A. Smithline Richard B. Wait 《The Journal of emergency medicine》2011
Background: Little has been written about the geographic basis of emergency department (ED) visits. Objective: The objective of this study is to describe the impact of geography on ED visits. Methods: A retrospective analysis was conducted of ED visits during a 1-year period at a single institution using spatial interaction analysis that models the pattern of flow between a series of origins (census block groups) and a destination (ED). Patients were assigned to census block groups based upon their verified home address. The study hospital is the only Level I trauma, pediatric, and tertiary referral center in the area. There are 11 other hospitals with EDs within a 40-mile radius. Each patient visit within this radius, including repeat visits, was included. Patients with an invalid home address, a post office box address, or those who lived outside a 40-mile radius were excluded. ED visits per 100 population were calculated for each census block group. Results: There were 98,584 (95%) visits by 63,524 patients that met study inclusion criteria. Visit rates decreased with increasing distance from the ED (p < 0.0001). Nineteen percent of patients lived within 2 miles, 48% within 4 miles, and 92% within 12 miles of the ED. The Connecticut border, 7 miles south of the ED (p < 0.0001), the Connecticut River, 1 mile west of the ED (p < 0.0001), and the presence of a competing ED within 1 mile (p < 0.0001) negatively impacted block group ED visit rates. Travel distance was related to the percentage of visits that were high acuity (p < 0.0001), daytime (p < 0.01), or resulted in admission (p < 0.0001). Conclusions: Geography and travel distance significantly impact ED visits. 相似文献
57.
As a part of the evaluation of Nottingham's response to the Changing Childbirth initiative, a cohort of pregnant women were asked to complete diaries, recording their perceptions of events and their feelings over the entire pregnancy period. Before the study began, we were concerned that the diary completion rate could be low and that those completing would be unrepresentative of the population. In this paper, we report the nature of responses to the diary and show that these problems were far less serious than was initially expected. A high degree of coverage was achieved, implying that large numbers of women were sufficiently motivated to maintain detailed records over many months. The research suggests that the diary is a viable method of data capture in such circumstances.Public Health (2001) 115, 108–113. 相似文献
58.
Kathryn D.I. CANDILO Wendy ODDY Margaret MILLER Nick SLOAN Garth KENDALL Nicholas D.E. KLERK 《Nutrition & Dietetics》2007,64(3):165-171
Aim: Our primary objective was to determine the effect of follow‐up phone calls on estimated nutrient intakes obtained by three‐day food diaries from 13‐year‐old adolescents. Methods: Food diaries were recorded using household measures and entered into a dietary analysis software program, before and after follow up by telephone. A sample of 340 participants aged 13 years born into the Western Australian Pregnancy Cohort (Raine) Study, a population‐based longitudinal cohort followed from 16 to 20 weeks' gestation to 13 years of age (current follow up). After face‐to‐face instruction, participants completed three‐day food diaries at home and returned them by post. Follow‐up telephone calls were made to each participant to improve data collection response and to verify missing details in the food diaries. Nutrient intakes before and after telephone follow up were compared using Student's t‐tests in spss . Results were also compared with those of the Child and Adolescent Physical Activity and Nutrition survey. Results: Follow‐up phone calls significantly increased the estimated intake of total kilojoules, water, total carbohydrates, sugars and magnesium (P < 0.05). Conclusion: These results indicate the importance of follow‐up phone calls to obtain missing details in three‐day food diaries completed by adolescents. 相似文献
59.
60.
FitzGerald MP Butler N Shott S Brubaker L 《Neurourology and urodynamics》2002,21(1):36-40; discussion 41
Patients commonly express bother with the symptom of frequent urination. The relationship between actual voiding frequency and this symptom is undocumented. We reviewed records of 200 women who had completed 24-hour frequency-volume charts, and had indicated their degree of bother with urinary frequency utilizing the short form of the Urogenital Distress Inventory. The degree of bother was correlated with daytime and nighttime voiding frequency, maximum functional capacity, mean voided volume, and demographic variables. Among 200 women, 180 (90%) indicated at least a minor degree of bother with urinary frequency. A voiding frequency of eight or more times in 24 hours was reported by 166 (83%) of women. Among the 34 women voiding fewer than eight times/24 hours, 26 (76%) reported bother with urinary frequency. There was large variation in the degree of bother reported at a given voiding frequency. Postmenopausal women without hormone replacement therapy (HRT) recorded more nighttime voids than those on HRT. Among postmenopausal women without HRT, mean voided volume and maximum functional capacity were inversely related to patient age. Our study suggests that the currently utilized cutoff value of eight daily voids to define urinary frequency, may not be helpful in the management of women in this country. A racially diverse study of the voiding habits of asymptomatic North American women is mandated. 相似文献