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   599篇
  免费   22篇
  国内免费   16篇
儿科学   36篇
妇产科学   2篇
基础医学   59篇
口腔科学   9篇
临床医学   68篇
内科学   127篇
皮肤病学   4篇
神经病学   14篇
特种医学   100篇
外科学   63篇
综合类   32篇
预防医学   45篇
眼科学   7篇
药学   34篇
中国医学   1篇
肿瘤学   36篇
  2022年   2篇
  2021年   8篇
  2020年   5篇
  2019年   13篇
  2018年   9篇
  2017年   7篇
  2016年   8篇
  2015年   18篇
  2014年   21篇
  2013年   26篇
  2012年   32篇
  2011年   24篇
  2010年   36篇
  2009年   18篇
  2008年   16篇
  2007年   32篇
  2006年   22篇
  2005年   16篇
  2004年   3篇
  2003年   12篇
  2002年   9篇
  2001年   11篇
  2000年   12篇
  1999年   17篇
  1998年   26篇
  1997年   29篇
  1996年   25篇
  1995年   20篇
  1994年   18篇
  1993年   15篇
  1992年   2篇
  1991年   4篇
  1990年   6篇
  1989年   21篇
  1988年   16篇
  1987年   12篇
  1986年   8篇
  1985年   6篇
  1984年   4篇
  1983年   8篇
  1982年   3篇
  1981年   7篇
  1980年   10篇
  1979年   2篇
  1978年   5篇
  1977年   2篇
  1976年   4篇
  1975年   2篇
  1925年   1篇
  1924年   1篇
排序方式: 共有637条查询结果,搜索用时 46 毫秒
21.
Abstract. Beulens JWJ, van der Schouw YT, Bergmann MM, Rohrmann S, B Schulze M, Buijsse B, Grobbee DE, Arriola L, Cauchi S, Tormo M‐J, Allen NE, van der A DL, Balkau B, Boeing H, Clavel‐Chapelon F, de Lauzon‐Guillan B, Franks P, Froguel P, Gonzales C, Halkjær J, Huerta JM, Kaaks R, Key TJ, Khaw KT, Krogh V, Molina‐Montes E, Nilsson P, Overvad K, Palli D, Panico S, Ramón Quirós J, Ronaldsson O, Romieu I, Romaguera D, Sacerdote C, Sánchez M‐J, Spijkerman AMW, Teucher B, Tjonneland A, Tumino R, Sharp S, Forouhi NG, Langenberg C, Feskens EJM, Riboli E, Wareham NJ (University Medical Center Utrecht, The Netherlands; German Institute of Human Nutrition, Potsdam‐Rehbrücke, Germany; German Cancer Research Centre, Heidelberg, Germany; Basque Government, San Sebastian, CIBERESP, Spain; Institut de Biologie de Lille, Lille, France; Murcia Regional Health Council, Murcia, Spain; CIBER Epidemiologia y Salud Publica (CIBERESP), Spain; University of Oxford, Oxford, UK; National Institute of Public Health and the Environment, Bilthoven, The Netherlands; Inserm, CESP Centre for Research in Epidemiology and Population Health, Villejuif Cedex, France; Lund University, Malmö, Sweden; Imperial College, London, UK; Department of Epidemiology, Barcelona, Spain; Danish Cancer Society, Copenhagen, Denmark; University of Cambridge, Cambridge, UK; Fondazione IRCCS Istituto Nazionale Tumori Milan, Milan, Italy; Andalusian School of Public Health, Granada, Spain; School of Public Health, Aarhus, Denmark; Cancer Research and Prevention Institute (ISPO), Florence, Italy; Università Federico II, Napoli, Italy; Consejeria de Salud y Servicios Sanitarios, Oviedo‐Asturias, Spain; Umea University, Umea, Sweden; International Agency for Research of Cancer, Lyon, France; Center for Cancer Prevention (CPO‐Piemonte), Torino, Italy; “Civile ‐ M.P. Arezzo” Hospital, Ragusa, Italy; Addenbrooke’s Hospital, Cambridge, UK; and Wageningen University, Wageningen, The Netherlands). Alcohol consumption and risk of type 2 diabetes in European men and women: influence of beverage type and body size. The EPIC–InterAct study. J Intern Med 2012; 272: 358–370. Objective: To investigate the association between alcohol consumption and type 2 diabetes, and determine whether this is modified by sex, body mass index (BMI) and beverage type. Design: Multicentre prospective case–cohort study. Setting: Eight countries from the European Prospective Investigation into Cancer and Nutrition cohort. Subjects: A representative baseline sample of 16 154 participants and 12 403 incident cases of type 2 diabetes. Interventions: Alcohol consumption assessed using validated dietary questionnaires. Main outcome measures: Occurrence of type 2 diabetes based on multiple sources (mainly self‐reports), verified against medical information. Results: Amongst men, moderate alcohol consumption was nonsignificantly associated with a lower incidence of diabetes with a hazard ratio (HR) of 0.90 (95% CI: 0.78–1.05) for 6.1–12.0 versus 0.1–6.0 g day?1, adjusted for dietary and diabetes risk factors. However, the lowest risk was observed at higher intakes of 24.1–96.0 g day?1 with an HR of 0.86 (95% CI: 0.75–0.98). Amongst women, moderate alcohol consumption was associated with a lower incidence of diabetes with a hazard ratio of 0.82 (95% CI: 0.72–0.92) for 6.1–12.0 g day?1 (P interaction gender <0.01). The inverse association between alcohol consumption and diabetes was more pronounced amongst overweight (BMI ≥ 25 kg m?2) than normal‐weight men and women (P interaction < 0.05). Adjusting for waist and hip circumference did not alter the results for men, but attenuated the association for women (HR=0.90, 95% CI: 0.79–1.03 for 6.1–12.0 g day?1). Wine consumption for men and fortified wine consumption for women were most strongly associated with a reduced risk of diabetes. Conclusions: The results of this study show that moderate alcohol consumption is associated with a lower risk of type 2 diabetes amongst women only. However, this risk reduction is in part explained by fat distribution. The relation between alcohol consumption and type 2 diabetes was stronger for overweight than normal‐weight women and men.  相似文献   
22.
Transplantation is the favored therapy for patients with end‐stage renal disease (ESRD). Unfortunately, demand for available organs far outpaces the supply. African Americans are disproportionately affected by the ever‐widening gap between organ supply and demand. Additionally, structural, biological, and social factors contribute to feelings of unease some African Americans may feel regarding living donor transplant (LDT). The present research examines the relationship between trust in health care and attitudes toward LDT among African American ESRD patients. We hypothesized that lower trust in health care would be significantly associated with negative attitudes toward LDT, and that this relationship would be moderated by patient attitudes toward dialysis. Data were collected from August 2011 to April 2012 as part of a larger study. Measures included trust (of doctors, racial equity of treatment, and hospitals) and attitudes toward both LDT and dialysis. Bivariate analysis revealed that trust in one's doctor, hospital, and in racial equity in health care was significantly correlated with attitudes toward LDT (r = 0.265; r = 0.131; and r = 0.202, respectively). Additionally, attitudes toward dialysis moderated the relationships between Trust in Doctors/Attitudes toward LDT and Trust in Racial equity of treatment/Attitudes toward LDT. Findings suggest a strong relationship between trust in health care and attitudes toward LDT. These findings also shed light on how dialysis experiences are related to the relationship between trust in health care and attitudes toward LDT.  相似文献   
23.
F. Lpez‐Medrano  J. T. Silva  M. Fernndez‐Ruiz  P. L. Carver  C. van Delden  E. Merino  M. J. Prez‐Saez  M. Montero  J. Coussement  M. de Abreu Mazzolin  C. Cervera  L. Santos  N. Sab  A. Scemla  E. Cordero  L. Cruzado‐Vega  P. L. Martín‐Moreno   . Len  E. Rudas  A. Ponce de Len  M. Arriola  R. Lauzurica  M. David  C. Gonzlez‐Rico  F. Henríquez‐Palop  J. Fortún  M. Nucci  O. Manuel  J. R. Pao‐Pardo  M. Montejo  P. Muoz  B. Snchez‐Sobrino  A. Mazuecos  J. Pascual  J. P. Horcajada  T. Lecompte  C. Lumbreras  A. Moreno  J. Carratal  M. Blanes  D. Hernndez  E. A. Hernndez‐Mndez  M. C. Farias  M. Perell‐Carrascosa  J. M. Morales  A. Andrs  J. M. Aguado   《American journal of transplantation》2016,16(7):2148-2157
Risk factors for invasive pulmonary aspergillosis (IPA) after kidney transplantation have been poorly explored. We performed a multinational case–control study that included 51 kidney transplant (KT) recipients diagnosed with early (first 180 posttransplant days) IPA at 19 institutions between 2000 and 2013. Control recipients were matched (1:1 ratio) by center and date of transplantation. Overall mortality among cases was 60.8%, and 25.0% of living recipients experienced graft loss. Pretransplant diagnosis of chronic pulmonary obstructive disease (COPD; odds ratio [OR]: 9.96; 95% confidence interval [CI]: 1.09–90.58; p = 0.041) and delayed graft function (OR: 3.40; 95% CI: 1.08–10.73; p = 0.037) were identified as independent risk factors for IPA among those variables already available in the immediate peritransplant period. The development of bloodstream infection (OR: 18.76; 95% CI: 1.04–339.37; p = 0.047) and acute graft rejection (OR: 40.73, 95% CI: 3.63–456.98; p = 0.003) within the 3 mo prior to the diagnosis of IPA acted as risk factors during the subsequent period. In conclusion, pretransplant COPD, impaired graft function and the occurrence of serious posttransplant infections may be useful to identify KT recipients at the highest risk of early IPA. Future studies should explore the potential benefit of antimold prophylaxis in this group.  相似文献   
24.
Current low participation rates in vector control programmes in Arequipa, Peru complicate the control of Chagas disease. Using focus groups (n?=?17 participants) and semi-structured interviews (n?=?71) conducted in March and May 2013, respectively, we examined barriers to and motivators of household participation in an indoor residual spray (IRS) campaign that had taken place one year prior in Arequipa. The most common reported barriers to participation were inconvenient spray times due to work obligations, not considering the campaign to be necessary, concerns about secondary health impacts (e.g. allergic reactions to insecticides), and difficulties preparing the home for spraying (e.g. moving heavy furniture). There was also a low perception of risk for contracting Chagas disease that might affect participation. The main motivator to participate was to ensure personal health and well-being. Future IRS campaigns should incorporate more flexible hours, including weekends; provide appropriate educational messages to counter concerns about secondary health effects; incorporate peer educators to increase perceived risk to Chagas in community; obtain support from community members and leaders to build community trust and support for the campaign; and assist individuals in preparing their homes. Enhancing community trust in both the need for the campaign and its operations is key.  相似文献   
25.
Although research shows that minorities exhibit higher levels of medical mistrust, perceived racism, and discrimination in healthcare settings, the degree to which these underlying sociocultural factors preclude end‐stage renal disease (ESRD) patients from initiating kidney transplant evaluation is unknown. We telephone surveyed 528 adult ESRD patients of black or white race referred for evaluation to a Georgia transplant center (N = 3) in 2014‐2016. We used multivariable logistic regression to examine associations between sociocultural factors and evaluation initiation, adjusting for demographic, clinical, and socioeconomic characteristics. Despite blacks (n = 407) reporting higher levels of medical mistrust (40.0% vs 26.4%, P < .01), perceived racism (55.5% vs 18.2%, P < .01), and experienced discrimination (29.0% vs 15.7%, P < .01) than whites (n = 121), blacks were only slightly less likely than whites to initiate evaluation (49.6% vs 57.9%, P = .11). However, after adjustment, medical mistrust (odds ratio [OR]: 0.59; 95% confidence interval [CI]: 0.39, 0.91), experienced discrimination (OR: 0.62, 95% CI: 0.41, 0.95), and perceived racism (OR: 0.61; 95% CI: 0.40, 0.92) were associated with lower evaluation initiation. Results suggest that sociocultural disparities exist in early kidney transplant access and occur despite the absence of a significant racial disparity in evaluation initiation. Interventions to reduce disparities in transplantation access should target underlying sociocultural factors, not just race.  相似文献   
26.
27.
To understand the hematopoietic and nonhematopoietic responses to interleukin-3 (IL-3), expression of cell-surface IL-3 receptors (IL-3R) was examined on bone marrow (BM) cells and peripheral blood (PB) cells of rhesus monkeys during the course of in vivo IL-3 treatment. Whereas IL-3R expression is low in untreated monkeys, IL-3 administration led to a gradual increase in both low- and high-affinity binding sites for IL-3. This increase reflected the total number of cells expressing IL- 3Rs, as detected by flow cytometry using biotinylated IL-3. Most of these IL-3R+ cells in both BM and PB could be characterized as basophilic granulocytes that contained high levels of histamine. In contrast to the effect on these differentiated cells, IL-3 administration did not significantly alter the low level IL-3R expression on immature, CD34+ cells. Further flow cytometric analysis using biotinylated growth factors showed that the IL-3R+ basophils also expressed receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF), but not for IL-6 or Kit ligand. These findings indicated that the IL-3R+ cells included neither monocytes, which express GM-CSFRs and IL-6Rs abundantly, nor mast cells, which express c- kit. By combining flow cytometric and Scatchard data, it was calculated that the basophils contain as many as 1 to 2 x 10(3) high-affinity IL- 3Rs and 15 to 30 x 10(3) low-affinity sites. The finding that in vivo IL-3 treatment leads to the production of large numbers of cells that express high levels of IL-3R and are capable of producing histamine provides an explanation for the often severe allergic reactions that occur during prolonged IL-3 administration. It also indicates that IL- 3, in addition to its direct effects on hematopoietic cells, may also stimulate hematopoiesis through the release of secondary mediators such as histamine by IL-3-responsive mature cells.  相似文献   
28.
Transcatheter valvulotomy in pulmonary atresia with an intact ventricular septum can be used as a first step to create biventricular circulation and to stimulate further development of the hypoplastic right ventricle. We describe our experience in a case of a neonate with this congenital cardiac defect who underwent successful transcatheter perforation of the atretic pulmonary valve. This report highlights the utility of a special technique based on the use of a gooseneck snare positioned just above the atretic valve to guide the advance of a coronary guidewire. Other therapeutic alternatives are considered.  相似文献   
29.
Thompson  AR; Chen  SH; Smith  KJ 《Blood》1988,72(5):1633-1638
In hemophilia B, assays based on a monoclonal antifactor IX specific for the Thr-148 variant of an exonic polymorphism have diagnosed carriers in selected families by either establishing linkage or by indicating the presence or absence of a given normal factor IX. The sensitivity of the immunoassays for detecting heterozygous women was explored by comparing results from immunoassays with solid-phase polyclonal v the monoclonal antifactor IXs. Factor IX with the normal Ala-148 variant gave a flat dilution curve, qualitatively distinct from factor IX with the Thr-148 variant in the monoclonal assay. The two were indistinguishable in the polyclonal assay. Mixtures of equal amounts of the two types gave an intermediate result, about half as reactive in the monoclonal as compared with the polyclonal assay system. Whereas mixtures with 10% Ala-148 and 90% Thr-148 factor IXs could not readily be distinguished from Thr-148 factor IX plasma, as little as 1% of the Thr-148 protein was detected in Ala-148 factor IX plasma. The frequency of the Ala-148 variant varied in individuals with different ethnic backgrounds; it was found in 29% of white, 12% of black, and none of Asian blood donors' factor IX genes in Seattle. Only 4% of samples from South African black men were nonreactive (ie, Ala- 148). The Thr/Ala-148 dimorphism is in strong linkage disequilibrium with Taql restriction fragment length polymorphisms (RFLPs). Three recombinations were noted in normal white genes and one in a normal black factor IX gene (less than 2% of those examined). In 34 white families with at least one woman being a possible carrier, genetically, the immunoassay results were informative in 18. RFLP analyses were informative in eight of the 15 families tested. In five families each, assignment of carrier status was made to a woman by only DNA or only immunoassay results, whereas the other approach was noninformative. The immunoassays provide a rapid, inexpensive screening test and complement DNA analysis in white women who are potential carriers of hemophilia B.  相似文献   
30.
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