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   1023篇
  免费   88篇
  国内免费   2篇
耳鼻咽喉   12篇
儿科学   58篇
妇产科学   26篇
基础医学   152篇
口腔科学   80篇
临床医学   125篇
内科学   141篇
皮肤病学   8篇
神经病学   159篇
特种医学   16篇
外科学   70篇
综合类   3篇
预防医学   153篇
眼科学   10篇
药学   63篇
肿瘤学   37篇
  2024年   2篇
  2023年   6篇
  2022年   13篇
  2021年   18篇
  2020年   24篇
  2019年   26篇
  2018年   32篇
  2017年   25篇
  2016年   32篇
  2015年   34篇
  2014年   40篇
  2013年   47篇
  2012年   92篇
  2011年   85篇
  2010年   48篇
  2009年   41篇
  2008年   84篇
  2007年   79篇
  2006年   60篇
  2005年   69篇
  2004年   68篇
  2003年   65篇
  2002年   49篇
  2001年   6篇
  2000年   4篇
  1999年   6篇
  1998年   8篇
  1997年   7篇
  1996年   7篇
  1995年   7篇
  1994年   5篇
  1993年   7篇
  1992年   6篇
  1991年   1篇
  1990年   2篇
  1989年   3篇
  1987年   1篇
  1984年   1篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
排序方式: 共有1113条查询结果,搜索用时 15 毫秒
101.
102.
103.
There is increasing evidence that healthy siblings of schizophrenia patients have similar, although milder, neuropsychological deficits than their affected family members. However, the interpretation of these findings has been complicated by methodological differences, for example the selection of relatives studied and the sensitivity of tests used. We studied neuropsychological functioning in schizophrenia families in representative, population-based samples of schizophrenia patients (n=81) and healthy siblings (n=78) from 58 families, and control subjects (n=70). We found that the healthy sibling group was impaired in tests measuring performance speed and executive functions. The patients were significantly impaired in all neuropsychological variables studied when compared with the control subjects, and also when compared with the healthy siblings. The effects of age, sex and education were controlled for. In conclusion, in a study of representative, population-based sample the healthy siblings of schizophrenia patients demonstrated deficits in processing speed and executive functions.  相似文献   
104.
CONTEXT: Patients with schizophrenia have an increased risk of type 2 diabetes mellitus. However, very few studies have dealt with the association of type 1 diabetes and schizophrenia. Preliminary evidence points to a possible inverse association. OBJECTIVE: To investigate the incidence of schizophrenia in a nationwide cohort of patients with type 1 diabetes born in 1950 through 1959 in Finland. DESIGN: A cohort study of individuals born in 1950 through 1959 with a follow-up of 1969 through 1991. SETTING: Finland. PATIENTS: All individuals born in 1950 through 1959 with type 1 diabetes were identified through nationwide registers. The incidence of schizophrenia until 1992 among the total 1950-1959 cohort and in individuals with type 1 diabetes was calculated using information from 3 health care registers. MAIN OUTCOME MEASURE: Incidence of schizophrenia. RESULTS: The incidence of schizophrenia was 0.21 per 10 000 person-years in the group with type 1 diabetes and 0.56 per 10 000 person-years in the group without type 1 diabetes (P < .001). CONCLUSION: The incidence of schizophrenia is decreased in patients with type 1 diabetes.  相似文献   
105.
PURPOSE: The 12Glu9 polymorphism of the alpha2B-adrenergic receptor gene may impair insulin secretion and modify the effects of a lifestyle intervention on the risk of type 2 diabetes, but the interaction with specific lifestyle components is unknown. We assessed the associations of leisure-time physical activity (LTPA), dietary changes, and weight loss on the risk of type 2 diabetes according to the 12Glu9 polymorphism in 481 participants of the Finnish Diabetes Prevention Study. METHODS AND RESULTS: The lifestyle intervention decreased the risk of diabetes in 9Glu carriers (9Glu9, intervention vs control, relative risk (RR) = 0.23, 95% confidence interval (CI) 0.09-0.62), but not in 12Glu12 homozygotes. In the combined intervention and control groups, increased total LTPA as estimated with a questionnaire decreased the risk of diabetes in 12Glu carriers (12Glu12, upper vs lower third, RR = 0.12, 95% CI 0.03-0.53) but not in 9Glu9 homozygotes (P for the interaction 0.033). In contrast, favorable dietary changes, estimated using a dietary score, reduced the risk of diabetes in those with the 9Glu9 genotype (upper vs lower third, RR = 0.21, 95% CI 0.06-0.75) but not in those with the 12Glu allele. Weight loss significantly decreased the risk of diabetes only in 12Glu carriers. CONCLUSION: Increased LTPA decreased the risk of type 2 diabetes more in those with the 12Glu allele of the ADRA2B gene, whereas dietary changes may have mediated the greater risk reduction of the lifestyle intervention in 9Glu homozygotes.  相似文献   
106.

Objectives:

Changes in health following retirement are poorly understood. We used serial measurements to assess the effect of retirement on sleep disturbances.

Design:

Prospective cohort study.

Setting:

The French national gas and electricity company.

Participants:

Fourteen thousand seven hundred fourteen retired employees (79% men).

Measurements and Results:

Annual survey measurements of sleep disturbances ranging from 7 years before to 7 years after retirement (a mean of 12 measurements). Before retirement 22.2% to 24.6% of participants reported having disturbed sleep. According to repeated-measures logistic-regression analysis with generalized estimating equations estimation, the odds ratio (OR) for having a sleep disturbance in the postretirement period was 0.74 (95% confidence interval 0.71-0.77), compared with having a sleep disturbance in the preretirement period. The postretirement improvement in sleep was more pronounced in men (OR 0.66 [0.63-0.69]) than in women (OR 0.89 [0.84-0.95]) and in higher-grade workers than lower-grade workers. Postretirement sleep improvement was explained by the combination of preretirement risk factors suggesting removal of work-related exposures as a mechanism. The only exception to the general improvement in sleep after retirement was related to retirement on health grounds. In this group of participants, there was an increase in sleep disturbances following retirement.

Conclusions:

Repeated measurements provide strong evidence for a substantial and sustained decrease in sleep disturbances following retirement. The possibility that the health and well-being of individuals are significantly worse when in employment than following retirement presents a great challenge to improve the quality of work life in Western societies in which the cost of the aging population can only be met through an increase in average retirement age.

Citation:

Vahtera J; Westerlund H; Hall M; Sjösten N; Kivimäki M; Salo P; Ferrie JE; Jokela M; Pentti J; Singh-Manoux A; Goldberg M; Zins M. Effect of retirement on sleep disturbances: the GAZEL prospective cohort study. SLEEP 2009;32(11):1459-1466.  相似文献   
107.
Following an outbreak caused by staphylococcal cassette chromosome mec (SCCmec) type V methicillin (meticillin)-resistant Staphylococcus aureus (MRSA), a point-prevalence survey of the nasal carriage of staphylococci was conducted in a long-term-care facility in northern Finland in 2004. The focus was directed at methicillin-resistant coagulase-negative staphylococci (MR-CNS) and their SCCmec elements. A nasal swab was taken from 76 of the 80 residents 6 months after the onset of the outbreak. Staphylococcal isolates were identified by conventional methods and the GenoType Staphylococcus test, and their SCCmec elements were analyzed. Of the 76 individuals, 24 (32%) carried S. aureus and 67 (88%) CNS in their nostrils. Of the CNS carriers, 41 (61%) had at least one mecA-positive MR-CNS, and two individuals (3%) had both MRSA and methicillin-resistant Staphylococcus epidermidis (MRSE). Among the 61 MR-CNS isolates identified, 49 (80%) were MRSE. The distribution of the SCCmec types was diverse: 20 (33%) were of type IV, 11 (18%) of type V, 4 (6%) of type I or IA, 3 (4%) of type II, and 23 (38%) of new types (with six different combinations of ccr and other mec genes or only mecA). Both of the individuals with MRSA and MRSE shared SCCmec type V among their isolates. Nasal MR-CNS carriage was common among the residents of this long-term-care facility. A variety of SCCmec types, including many new types, were identified among the MR-CNS strains. The horizontal transfer of SCCmec elements is speculated based on the sharing of SCCmec type V between MRSA and MRSE.  相似文献   
108.
BACKGROUND: There are few reports on mobility limitations in persons with psychotic disorder although restrictions in mobility may aggravate the general functional limitations of these patients. Our aim was to investigate mobility limitations among subjects with psychotic disorder in a general population-based sample. METHODS: A nationally representative sample of 6,927 persons aged 30 and older self-reported mobility limitations in an interview and was examined in performance tests. Diagnostic assessment of DSM-IV psychotic disorders combined SCID interview and case note data. Lifetime-ever diagnoses of psychotic disorder were classified into schizophrenia, other nonaffective psychotic disorders and affective psychoses. RESULTS: Self-reported mobility limitations were highly prevalent in persons with schizophrenia and other nonaffective psychosis, but not in the affective psychosis group. After adjusting for age and sex, persons with schizophrenia and other nonaffective psychoses but not affective psychoses had significantly increased odds of having both self-reported and test-based mobility limitations as well as weak muscle strength. Schizophrenia remained an independent predictor of mobility limitations even after controlling for lifestyle-related factors and chronic medical conditions. Among persons with nonaffective psychoses, higher levels of negative symptoms predicted mobility limitations. CONCLUSION: Self-reported mobility limitations are prevalent already at a young age in persons with schizophrenia and other nonaffective psychotic disorders, and among older persons with these disorders both self-reported limitations and measured performance tests show lower capacity in mobility. Difficulties in mobility are associated with negative symptoms. Mental health care professionals should pay attention to mobility limitations in persons with psychotic disorder.  相似文献   
109.
BACKGROUND: Geographical variation and sociodemographic characteristics may differ in affective and nonaffective psychotic disorders. We examined the geographical variation in the lifetime prevalence of psychotic disorders in a comprehensive general population study. METHOD: A nationally representative sample of 8028 Finns aged 30 or over was screened for psychotic and bipolar I disorders and interviewed with the Structured Clinical Interview for DSM-IV. Best-estimate DSM-IV diagnoses were formed by combining interview and case note data. Nationwide health care register data were used for the nonrespondents. Associations with sociodemographic features, place of birth and residence in urban or rural areas and in five regions, and migration between the regions were examined. RESULTS: Schizophrenia and other nonaffective psychoses, but not affective psychoses, showed prominent regional variation, with highest odds found for schizophrenia among those born in the North (OR 7.72 95%CI 2.48-24.04) and the East (OR 3.99 95%CI 1.22-13.11). The risk of any psychotic disorder was lower for those born in urban areas (OR 0.73 95%CI 0.54-0.98), but no associations were found for separate diagnostic groups. Region of birth was the strongest determinant of geographical variation when both place of birth and residence were accounted for. Selective migration was not found. Education and income were higher and being employed more common in subjects with affective psychosis than in subjects with other psychotic disorders. CONCLUSIONS: Large area variation is more important than urban-rural disparity in psychotic disorders in Finland. Affective psychoses were different from nonaffective psychoses in terms of both regional variation and sociodemographic features.  相似文献   
110.
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