全文获取类型
收费全文 | 36886篇 |
免费 | 4488篇 |
国内免费 | 439篇 |
专业分类
耳鼻咽喉 | 578篇 |
儿科学 | 6564篇 |
妇产科学 | 246篇 |
基础医学 | 2837篇 |
口腔科学 | 1110篇 |
临床医学 | 4645篇 |
内科学 | 3509篇 |
皮肤病学 | 439篇 |
神经病学 | 1793篇 |
特种医学 | 506篇 |
外科学 | 2103篇 |
综合类 | 4214篇 |
现状与发展 | 2篇 |
一般理论 | 2篇 |
预防医学 | 7950篇 |
眼科学 | 992篇 |
药学 | 2783篇 |
43篇 | |
中国医学 | 897篇 |
肿瘤学 | 600篇 |
出版年
2024年 | 506篇 |
2023年 | 837篇 |
2022年 | 1310篇 |
2021年 | 1784篇 |
2020年 | 1818篇 |
2019年 | 1443篇 |
2018年 | 1323篇 |
2017年 | 1527篇 |
2016年 | 1676篇 |
2015年 | 1415篇 |
2014年 | 2333篇 |
2013年 | 3200篇 |
2012年 | 2174篇 |
2011年 | 2293篇 |
2010年 | 1919篇 |
2009年 | 1682篇 |
2008年 | 1591篇 |
2007年 | 1688篇 |
2006年 | 1493篇 |
2005年 | 1329篇 |
2004年 | 1122篇 |
2003年 | 902篇 |
2002年 | 822篇 |
2001年 | 696篇 |
2000年 | 537篇 |
1999年 | 449篇 |
1998年 | 501篇 |
1997年 | 438篇 |
1996年 | 385篇 |
1995年 | 304篇 |
1994年 | 301篇 |
1993年 | 238篇 |
1992年 | 182篇 |
1991年 | 185篇 |
1990年 | 163篇 |
1989年 | 159篇 |
1988年 | 132篇 |
1987年 | 98篇 |
1986年 | 131篇 |
1985年 | 99篇 |
1984年 | 77篇 |
1983年 | 74篇 |
1982年 | 57篇 |
1981年 | 60篇 |
1980年 | 57篇 |
1979年 | 51篇 |
1978年 | 36篇 |
1977年 | 33篇 |
1976年 | 54篇 |
1975年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Lynne S. Schilling RN PhD Margaret Grey DrPH FAAN CPNP & Kathleen A. Knafl PhD 《Journal of advanced nursing》2002,37(1):87-99
AIM: An evolutionary concept analysis was undertaken to clarify the concept of self-management of type 1 diabetes in children and adolescents. BACKGROUND: Several problems exist in the literature on self-management of type 1 diabetes in children and adolescents. There is no uniform terminology and there is no uniform definition of the concept. Also, there is no differentiation in the literature between self-management of diabetes in children and adults. METHODS: Ninety-nine references were reviewed and analysed in the disciplines of nursing, medicine, and psychology. After separate analyses revealed no significant differences across disciplines, the analyses were combined to describe the attributes, antecedents, consequences, and surrogate and related concepts. RESULTS: The three essential attributes of the concept were identified as process, activities, and goals. Self-management of type 1 diabetes in children and adolescents is an active and proactive process; it is daily, lifelong, and flexible, and it involves shifting and shared responsibility for diabetes care tasks and decision-making between child and parent. It is a process that involves collaboration with health care providers. Self-management of type 1 diabetes in children and adolescents also consists of varied and many activities related to giving insulin, monitoring metabolic control, regulating diet and exercise, to name just a few. The concept also involves goals, which may differ from one parent/child dyad to another. A working definition of the concept is suggested. CONCLUSIONS: It is hoped that a more uniform definition of the concept will enable researchers to continue investigating antecedents and consequences of the concept in a way that allows for aggregating results. 相似文献
42.
E. Rigotti G. L. Piacentini M. Ress R. Pigozzi A. L. Boner D. G. Peroni 《Clinical and experimental allergy》2006,36(5):614-618
BACKGROUND: Precise relationship between breastfeeding and infant allergy is poorly understood. Objective Aim was to quantify TGF-beta(1) and IL-10 in colostrum and mature milk from allergic and non-allergic mothers and to verify relationship with allergic disease development. METHODS: Mothers (13 allergics, nine controls) of 22 newborns participated to prospective study on development of children atopy. Colostrum and mature milk were assayed for TGF-beta(1) and IL-10 by ELISA. Children underwent paediatrician evaluation at 6 months of life. RESULTS: Data are presented as median values and range. A significant difference in concentration of TGF-beta(1) between colostrum (330, range 0-3400 pg/mL) and mature milk (215, range 0-2400 pg/mL) was observed in samples from allergic mothers (P=0.015). In mature milk TGF-beta(1) was significantly lower in allergic (215, range 0-2400 pg/mL) than in non-allergic mothers (1059, range 0-6250 pg/mL) (P=0.015). IL-10 was weakly expressed without significant differences between allergic (4.8, range 0-42 and 9.5, range 0-42 pg/mL in colostrum and in mature milk) and non-allergic mothers (0, range 0-42 pg/mL in colostrum and 0, range 0-42 pg/mL in mature milk). After 6 months 46% infants from allergic mothers, but none from controls, presented atopic dermatitis. CONCLUSION: TGF-beta(1) was significantly less secreted in mature milk of allergic mothers, while no difference in IL-10 was found. Particular cytokine patterns in milk could influence development of atopic diseases. Further immunological studies in this field are necessary. 相似文献
43.
C. C. Roehr G. Edenharter† S. Reimann‡ I. Ehlers‡ M. Worm‡ T. Zuberbier‡ B. Niggemann 《Clinical and experimental allergy》2004,34(10):1534-1541
BACKGROUND: Previous studies have shown a 10-fold discrepancy of self-reported food-induced symptoms and physician-diagnosed food hypersensitivity. Little information is available on the prevalence of food hypersensitivity in unselected paediatric populations. No data were available for German children. OBJECTIVE: To study the perception of food-induced symptoms in the paediatric population, to investigate the allergens accused, to objectify patients' reports, and to identify subgroups at risk of having food-induced allergy (FA) or non-allergic food hypersensitivity (NAFH) reactions. METHODS: This paper presents the data of the paediatric group (0-17 years) of a representative, randomly sampled, cross-sectional population-based survey studying 13 300 inhabitants of the German capital city Berlin regarding food-related symptoms. Instruments included mailed questionnaires, structured telephone interviews, physical examination, skin-prick tests, specific serum IgE and standardized, controlled and blinded oral food challenges. RESULTS: Two thousand three hundred and fifty-four individuals were contacted by mailed questionnaire, 739 (31.4%) responses could be fully evaluated. Four hundred and fifty-five (61.5%) participants reported symptoms related to food ingestion, 284 (38.4%) affirmed reproducible symptoms in the standardized telephone interview. One hundred and eighty-four (24.8%) individuals were fully examined. Reproducible symptoms to food were found in 31 (4.2%) children and adolescents: 26 (3.5%) showed symptoms of FA and five (0.7%) of NAFH. The oral allergy syndrome was most often observed. Foods most commonly identified by oral challenges were apple, hazelnut, soy, kiwi, carrot and wheat. CONCLUSION: The perception of food-related symptoms is common among children and adolescents from the general population. Self-reports could be confirmed in around one out of 10 individuals, still resulting in 4.2% of proven clinical symptoms. However, most reactions were mild and mainly because of pollen-associated FA, while NAFH reactions were less common. Severe IgE-mediated FA was observed in individuals with pre-existing atopic disease, who should be fully investigated for clinically relevant FA. 相似文献
44.
M. Engberg 《Acta psychiatrica Scandinavica》1994,89(1):35-40
The mortality and suicide rates for involuntarily committed patients in Denmark are presented. Two cohorts of psychiatric patients committed to a mental hospital from January 1, 1971 to December 31, 1975 (8322 people) and January 1, 1981 to December 31, 1985 (5253 people) have been followed. The standard mortality rate (SMR) in relation to the total Danish population were 4.9 (4.5–5.4) and 5.2 (4.7–5.8), respectively, for the two cohorts, during the first year after involuntarily commitment to a mental hospital. During the same period, the SMR for suicide among the committed patients were 44.9 (37.1–53.9) and 30.9 (24.2–38.9), respectively. The crude suicide rates among the committed patients during the first year after the commitment were 14.3 and 14.0, respectively, per 1000 years, unchanged between the cohorts. Short length of stay in hospital (< 14 days), a nonpsychotic main diagnosis, male sex, and age 35 years or more were equally related to high risk of suicide in the 1971 cohort as evaluated to proportional hazard methods (Cox regression), and short length of stay and commitment on the danger indication provided the most information in relation to high suicidal risk in the 1981 cohort. Methodological problems and the reasons for the results are discussed. 相似文献
45.
46.
Michael R. Perkin David P. Strachan Hywel C. Williams Cameron T. C. Kennedy Jean Golding the ALSPAC Study Team 《Pediatric allergy and immunology》2004,15(3):221-229
We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n = 34), intermittent early onset (before 18 months of age, n = 495), intermittent late onset (18–42 months of age, n = 273) and unaffected ( n = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1–14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%. 相似文献
47.
Nuthapong Ukarapol Nirush Lertprasertsuk George J. Fuchs Lumduan Wongsawasdi Virat Sirisanthana 《Digestive endoscopy》2004,16(1):26-29
Objective: To evaluate the role of gastrointestinal (GI) endoscopy in human immunodeficiency virus (HIV)‐infected children with GI problems. Methods: From 1998 to 2002, we retrospectively reviewed all cases of HIV‐infected children presenting with GI problems in which an upper or lower GI endoscopy was indicated. The initial diagnostic endoscopic examination and any repeat endoscopic session leading to a new diagnosis were used in the data analysis. Tissue biopsies were obtained from all abnormal lesions and representative sites of normal‐appearancing GI mucosa. Results: Fourteen patients (median age: 22.5 months) underwent 23 sessions of GI endoscopy, including 10 esophagogastroduodenoscopy, nine colonoscopy and four flexible sigmoidoscopy. Chronic diarrhea was the most common indication, followed by lower GI bleeding, abdominal/retrosternal pain, dysphagia/odynophagia, and upper GI bleeding. Gross endoscopic abnormalities were observed in 78.3%; whereas histological inflammation and opportunistic pathogens were identified in 87% and 43.5%, respectively. Cytomegalovirus was the most common identified pathogen. Abnormal gross findings were significantly associated with histological inflammation and identification of pathogens (P = 0.006 and 0.046, respectively). Specific changes in medical management were made in 50% of cases as a result of endoscopic investigation. Conclusion: If non‐invasive investigations for HIV‐infected children with GI symptoms fail to establish a diagnosis, gastrointestinal endoscopy should be performed and often yields a positive result leading to changes in medical management. 相似文献
48.
Ikwunga Wonodi Gloria Reeves Dana Carmichael Ilene Verovsky Matthew T Avila Amie Elliott L Elliot Hong Helene M Adami Gunvant K Thaker 《Movement disorders》2007,22(12):1777-1782
Recent years have witnessed increased antipsychotic treatment of children despite limited long‐term safety data in children. In this study, motor side effects associated with the use of antipsychotic drugs in children were examined in a sample of pediatric psychiatric patients. Child and adolescent psychiatric patients receiving antipsychotics (most were on atypicals) for 6 months or longer (n = 118) were compared with antipsychotic‐naïve patients (n = 80) with similar age, sex ratio, and diagnoses. Only 19% of patients on antipsychotics had ever experienced psychotic symptoms. Eleven children (9%) on antipsychotics exhibited dyskinesia, when compared with 0 in the naïve group (P = 0.003, Fisher's exact test). Nine of 62 African–American children (15%) on antipsychotics exhibited dyskinesia, when compared with only 4% (2 of 52) of European–American children (P = 0.003, Fisher's exact test). Children treated with antipsychotic drugs might experience a significant risk of dyskinesia even when treated only with atypical antipsychotics. Ethnicity might also be a risk factor for dyskinesia in children. Side‐effect profile of the atypical antipsychotic drugs in children may be much different than that in adults. © 2007 Movement Disorder Society 相似文献
49.
Cristina Antúnez María Jose Torres Cristobalina Mayorga José L. Corzo Antonio Jurado Luis F. Santamaría-Babi Angel Vera Miguel Blanca 《Pediatric allergy and immunology》2006,17(3):166-174
T cells are known to develop a critical role in the pathogenesis of atopic dermatitis (AD) and bronchial asthma. T cells involved in AD express the skin homing receptor CLA, but no lung homing receptor has been identified in bronchial asthma. We compared different cell markers and the cytokine production in T cells from children with AD or bronchial asthma. We studied the involvement of CLA+ and CLA- T-cell subpopulations in these diseases. We studied 20 children with acute AD lesions, 15 with mild persistent asthma, and 15 non-atopic controls. All patients were sensitized to house dust mite (DP) and evaluated during the acute phase. Total and specific IgE were measured by immunoassay and the expression of different cell markers and the cytokine production was analyzed by flow cytometry in peripheral blood mononuclear cells. Total IgE was significantly higher in AD children and IgE to DP in the asthmatic children. There was a significant increase in CD25+ CD4+ cells in asthmatic children and in HLA-DR+ CD4+ and HLA-DR+ CD8+ cells in AD. In the CD4+ subsets, there was an increase in IL-13, IL-5 and TNF-alpha in AD compared to controls, a decrease in IFN-gamma in asthmatic children compared to controls, and an increase in IL-13, IL5, IL2, TNF-alpha, and IFN-gamma in the AD compared to asthmatic children. Changes in cytokine production were mainly detected in CLA+ cells in AD and in CLA- cells in asthma. Differences exist in total and specific IgE, activation markers, and cytokine patterns between AD children and children with asthma, with the former expressing a Th2 pattern whereas in asthmatic children we only detected a decrease in IFN-gamma. Moreover, the subpopulations (CLA+ vs. CLA-) expressing these changes were different, indicating that the underlying mechanisms in the two diseases are not exactly the same. 相似文献
50.
E. M. Fredericks M. J. Lopez J. C. Magee V. Shieck L. Opipari-Arrigan 《American journal of transplantation》2007,7(8):1974-1983
The present study empirically assessed the relationships between adherence behaviors and HRQOL, parent and child psychological functioning and family functioning, and investigated the relationship between adherence behaviors and health outcomes in children who were within 5 years of their liver transplantation. Participants included 38 children (mean = 8.5 years, range 28 months to 16 years) and their parent/guardian(s). HRQOL and psychological functioning were examined using well-validated assessment measures. Measures of adherence included the rate of clinic attendance and standard deviations (SDs) of consecutive tacrolimus blood levels, which were collected and evaluated retrospectively. Measures of child health status included the frequency of hospital admissions, liver biopsies, episodes of rejection and graft function for the year prior to study participation. Results indicated that nonadherence was related to lower physical HRQOL, more limitations in social and school activities related to emotional and behavioral problems, parental emotional distress and decreased family cohesion. Nonadherence was also related to frequency and duration of hospitalizations, liver biopsies and rejection episodes. These results suggest that empirically based assessment of HRQOL, parenting stress and family functioning may help identify patients at risk for nonadherence, and may allow for the need-based delivery of appropriate clinical interventions. 相似文献