全文获取类型
收费全文 | 7225篇 |
免费 | 534篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 211篇 |
妇产科学 | 173篇 |
基础医学 | 916篇 |
口腔科学 | 129篇 |
临床医学 | 835篇 |
内科学 | 1339篇 |
皮肤病学 | 85篇 |
神经病学 | 770篇 |
特种医学 | 147篇 |
外科学 | 1020篇 |
综合类 | 54篇 |
一般理论 | 14篇 |
预防医学 | 808篇 |
眼科学 | 167篇 |
药学 | 561篇 |
中国医学 | 4篇 |
肿瘤学 | 434篇 |
出版年
2023年 | 73篇 |
2022年 | 126篇 |
2021年 | 306篇 |
2020年 | 167篇 |
2019年 | 245篇 |
2018年 | 257篇 |
2017年 | 202篇 |
2016年 | 213篇 |
2015年 | 247篇 |
2014年 | 309篇 |
2013年 | 473篇 |
2012年 | 632篇 |
2011年 | 583篇 |
2010年 | 285篇 |
2009年 | 274篇 |
2008年 | 460篇 |
2007年 | 467篇 |
2006年 | 418篇 |
2005年 | 406篇 |
2004年 | 319篇 |
2003年 | 239篇 |
2002年 | 238篇 |
2001年 | 60篇 |
2000年 | 62篇 |
1999年 | 47篇 |
1998年 | 44篇 |
1997年 | 28篇 |
1996年 | 27篇 |
1995年 | 19篇 |
1994年 | 14篇 |
1993年 | 20篇 |
1992年 | 35篇 |
1991年 | 32篇 |
1990年 | 29篇 |
1989年 | 26篇 |
1988年 | 37篇 |
1987年 | 33篇 |
1986年 | 26篇 |
1985年 | 25篇 |
1984年 | 26篇 |
1983年 | 18篇 |
1980年 | 13篇 |
1979年 | 12篇 |
1978年 | 24篇 |
1977年 | 19篇 |
1976年 | 15篇 |
1975年 | 14篇 |
1974年 | 13篇 |
1973年 | 17篇 |
1969年 | 10篇 |
排序方式: 共有7772条查询结果,搜索用时 62 毫秒
101.
Jennifer L. Biggs Jamie S. Sutherell Rochelle Remus Eric S. Armbrecht 《Teaching and learning in medicine》2018,30(2):202-212
Problem: Student–preceptor discontinuity during 3rd-year clerkships limits the quality and quantity of supervision, teaching, and feedback. Although longitudinal integrative clerkships increase continuity and are associated with improved student and preceptor experience, they require schoolwide curricular reform. Alternative innovations enhancing student–preceptor relationships within the constraints of a traditional block clerkship may demonstrate similar benefits. Intervention: We piloted a continuity-enhanced general pediatric ambulatory schedule during 2 consecutive clerkship blocks in 2013. Students in the continuity-enhanced model (n = 29) were assigned 1–3 primary clinic preceptors, whereas those in the traditional model (n = 30) worked with 5–8. Data were gathered from student assessments and anonymous student and preceptor surveys. We used t and Fisher's exact tests to compare the two groups and performed thematic analysis of free-text survey comments. Context: Our school utilizes a block clerkship model with approximately 30 students rotating through the pediatric clerkship every 8 weeks. During the 3-week ambulatory portion, students spend 8 half days in the general pediatric ambulatory clinic. At the conclusion of each clinic, attendings completed brief student evaluation cards. Traditionally, student and attending schedules were created independently, resulting in transient supervisory relationships and dissatisfaction with clinical engagement, feedback, and evaluation. Outcome: Seventy-three percent (43/59) of the students completed the survey. Ten general ambulatory attendings collectively completed 87.5% (35/40) of the monthly surveys. Continuity students received significantly more narrative evaluation comments (10.6 vs. 5.8, p <. 001) from general ambulatory clinic attendings and were more likely to have at least one general ambulatory clinic attending endorse being able to provide meaningful feedback and evaluation (n = 29, 100% vs. n = 20, 66.7%, p <. 001). Continuity students were also more likely to endorse being able to ask at least one of these attendings for a letter of recommendation (71.4% vs. 9.1%, p <. 001) and to have at least one general ambulatory clinic attending endorse being able to provide a meaningful letter of recommendation if asked (62.1% vs. 3.3%, p <. 001). Students (88.4%) and attendings (85.7%) preferred the continuity-enhanced schedule. The most frequent theme of both student and attending free-text survey remarks were relationships and assessment. Lessons Learned: Intentional scheduling of clerkship students to enhance preceptor continuity resulted in significant positive outcomes echoing the relationship-based educational benefits of longitudinal clerkships, particularly in regards to student assessment and feedback. Clerkship directors and other medical educators should consider implementing small changes within block clerkships to maximize student–preceptor continuity. 相似文献
102.
103.
Lance Brendan Young Kathleen M. Grant R. Dario Pulido Jamie L. Simpson Kimberly A. Tyler Christine Timko 《Alcoholism treatment quarterly》2018,36(2):179-201
Community-based support group participation protects against substance use disorder (SUD) relapse, but referrals during treatment are inconsistently delivered and may not acknowledge barriers facing rural patients. This formative evaluation of a rural intensive referral intervention (RAIR) to community-based support groups for Veterans seeking SUD treatment surveyed patients (n = 145) and surveyed and interviewed treatment staff (n = 28). Patients and staff did not differ significantly on quantitative ratings of the helpfulness of, or satisfaction with, seven RAIR components, but staff did not deliver the intervention consistently or as designed, citing two themes: lack of commitment and lack of resources. 相似文献
104.
Annice Kim James Nonnemaker Jamie Guillory Paul Shafer Sarah Parvanta John Holloway 《Journal of health communication》2017,22(6):477-487
Efforts are underway to educate consumers about the dangers of smoking at the point of sale (POS). Research is limited about the efficacy of POS antismoking ads to guide campaign development. This study experimentally tests whether the type of antismoking ad and the context in which ads are viewed influence people’s reactions to the ads. A national convenience sample of 7,812 adult current smokers and recent quitters was randomized to 1 of 39 conditions. Participants viewed one of the four types of antismoking ads (negative health consequences—graphic, negative social consequences—intended emotive, benefits of quitting—informational, benefits of quitting—graphic) in one of the three contexts (alone, next to a cigarette ad, POS tobacco display). We assessed participants’ reactions to the ads, including perceived effectiveness, negative emotion, affective dissonance, and motivational reaction. Graphic ads elicited more negative emotion and affective dissonance than benefits of quitting ads. Graphic ads elicited higher perceived effectiveness and more affective dissonance than intended emotive ads. Antismoking ads fared best when viewed alone, and graphic ads were least influenced by the context in which they were viewed. These results suggest that in developing POS campaigns, it is important to consider the competitive pro-tobacco context in which antismoking ads will be viewed. 相似文献
105.
106.
Paul H. Lysaker Bethany L. Leonhardt Martin Brüne Kelly D. Buck Alison James Jenifer Vohs Michael Francis Jay A. Hamm Giampaolo Salvatore Jamie M. Ringer Giancarlo Dimaggio 《Psychiatry research》2014
While many with schizophrenia spectrum disorders experience difficulties understanding the feelings of others, little is known about the psychological antecedents of these deficits. To explore these issues we examined whether deficits in mental state decoding, mental state reasoning and metacognitive capacity predict performance on an emotion recognition task. Participants were 115 adults with a schizophrenia spectrum disorder and 58 adults with substance use disorders but no history of a diagnosis of psychosis who completed the Eyes and Hinting Test. Metacognitive capacity was assessed using the Metacognitive Assessment Scale Abbreviated and emotion recognition was assessed using the Bell Lysaker Emotion Recognition Test. Results revealed that the schizophrenia patients performed more poorly than controls on tests of emotion recognition, mental state decoding, mental state reasoning and metacognition. Lesser capacities for mental state decoding, mental state reasoning and metacognition were all uniquely related emotion recognition within the schizophrenia group even after controlling for neurocognition and symptoms in a stepwise multiple regression. Results suggest that deficits in emotion recognition in schizophrenia may partly result from a combination of impairments in the ability to judge the cognitive and affective states of others and difficulties forming complex representations of self and others. 相似文献
107.
Emma Beard John Marsden Jamie Brown Ildiko Tombor John Stapleton Susan Michie Robert West 《Addiction (Abingdon, England)》2019,114(10):1866-1884
Time series analyses are statistical methods used to assess trends in repeated measurements taken at regular intervals and their associations with other trends or events, taking account of the temporal structure of such data. Addiction research often involves assessing associations between trends in target variables (e.g. population cigarette smoking prevalence) and predictor variables (e.g. average price of a cigarette), known as a multiple time series design, or interventions or events (e.g. introduction of an indoor smoking ban), known as an interrupted time series design. There are many analytical tools available, each with its own strengths and limitations. This paper provides addiction researchers with an overview of many of the methods available (GLM, GLMM, GLS, GAMM, ARIMA, ARIMAX, VAR, SVAR, VECM) and guidance on when and how they should be used, sample size det ermination, reporting and interpretation. The aim is to provide increased clarity for researchers proposing to undertake these analyses concerning what is likely to be acceptable for publication in journals such as Addiction. Given the large number of choices that need to be made when setting up time series models, the guidance emphasizes the importance of pre‐registering hypotheses and analysis plans before the analyses are undertaken. 相似文献
108.
Anna Semaniakou Sarah Brothers Grayson Gould Mehrsa Zahiremani Jamie Paton Frederic Chappe Audrey Li Younes Anini Roger P. Croll Valerie Chappe 《Journal of cystic fibrosis》2021,20(1):154-164
Vasoactive Intestinal Peptide (VIP) is the major physiological agonist of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride channel activity. VIP functions as a neuromodulator and neurotransmitter secreted by neurons innervating all exocrine glands. VIP is also a potent vasodilator and bronchodilator that regulates exocrine gland secretions, contributing to local innate defense by stimulating the movement of water and chloride transport across intestinal and tracheobronchial epithelia. Previous human studies have shown that the rich intrinsic neuronal networks for VIP secretion around exocrine glands could be lost in tissues from patients with cystic fibrosis. Our research has since confirmed, in vitro and in vivo, the need for chronic VIP exposure to maintain functional CFTR chloride channels at the cell surface of airways and intestinal epithelium, as well as normal exocrine tissues morphology [1]. The goal of the present study was to examine changes in VIP in the lung, duodenum and sweat glands of 8- and 17-weeks old F508del/F508del mice and to investigate VIPergic innervation in the small intestine of CF mice, before important signs of the disease development. Our data show that a low amount of VIP is found in CF tissues prior to tissue damage. Moreover, we found a specific reduction in VIPergic and cholinergic innervation of the small intestine. The general innervation of the primary and secondary myenteric plexus was lost in CF tissues, with the presence of enlarged ganglionic cells in the tertiary layer. We propose that low amount of VIP in CF tissues is due to a reduction in VIPergic and cholinergic innervation and represents an early defect that constitutes an aggravating factor for CF disease progression. 相似文献
109.
110.
Matthew Moyle Ferda Cevikbas Jamie L. Harden Emma Guttman‐Yassky 《Experimental dermatology》2019,28(7):756-768
Atopic dermatitis (AD) is a chronic, systemic, inflammatory disease that affects the skin and is characterized by persistent itch and marked redness. AD is associated with an increased risk of skin infections and a reduced quality of life. Most AD treatment options to date were not designed to selectively target disease‐causing pathways that have been established for this indication. Topical therapies have limited efficacy in moderate‐to‐severe disease, and systemic agents such as corticosteroids and immunosuppressants present with tolerability issues. Advances in the understanding of AD pathobiology have made possible a new generation of more disease‐specific AD therapies. AD is characterized by the inappropriate activation of type 2 T helper (Th2) cells and type 2 innate lymphoid (ILC2) cells, with a predominant increase in type 2 cytokines in the skin, including interleukin (IL)‐13 and IL‐4. Both cytokines are implicated in tissue inflammation and epidermal barrier dysfunction, and monoclonal antibodies targeting each of these interleukins or their receptors are in clinical development in AD. In March 2017, dupilumab, a human anti–IL‐4Rα antibody, became the first biologic to receive approval in the United States for the treatment of moderate‐to‐severe AD. The anti–IL‐13 monoclonal antibodies lebrikizumab and tralokinumab, which bind different IL‐13 epitopes with potentially different effects, are currently in advanced‐stage trials. Here, we briefly review the underlying pathobiology of AD, the scientific basis for current AD targets, and summarize current clinical studies of these agents, including new research to develop both predictive and response biomarkers to further advance AD therapy in the era of precision medicine. 相似文献