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   684篇
  免费   51篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   27篇
妇产科学   14篇
基础医学   102篇
口腔科学   11篇
临床医学   91篇
内科学   135篇
皮肤病学   22篇
神经病学   108篇
特种医学   15篇
外科学   36篇
预防医学   86篇
眼科学   9篇
药学   38篇
中国医学   2篇
肿瘤学   40篇
  2024年   3篇
  2023年   7篇
  2022年   11篇
  2021年   11篇
  2020年   12篇
  2019年   19篇
  2018年   16篇
  2017年   26篇
  2016年   24篇
  2015年   24篇
  2014年   28篇
  2013年   50篇
  2012年   53篇
  2011年   42篇
  2010年   29篇
  2009年   30篇
  2008年   30篇
  2007年   43篇
  2006年   42篇
  2005年   40篇
  2004年   45篇
  2003年   38篇
  2002年   27篇
  2001年   13篇
  2000年   4篇
  1999年   12篇
  1998年   6篇
  1997年   8篇
  1996年   5篇
  1995年   6篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   2篇
  1990年   1篇
  1989年   2篇
  1987年   2篇
  1986年   1篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1982年   4篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   4篇
  1975年   1篇
  1973年   1篇
  1968年   1篇
排序方式: 共有738条查询结果,搜索用时 15 毫秒
21.

Introduction and hypothesis

To estimate the incidence rates of stress urinary incontinence (SUI) surgery among Finnish women from 1987 to 2009 by age, and to evaluate the trends in SUI surgery.

Methods

We conducted a retrospective register-based study. All SUI procedures on adult women over age 18 years in Finland were identified from the nationwide Care Register for Health Care. Age-specific incidence rates per 1,000 women were calculated for each year. The cumulative incidence of SUI surgery was calculated.

Results

There were 38,340 procedures for SUI in 1987–2009. The overall age-adjusted incidence rate increased 2.6-fold from 0.5/1,000 women in 1987 to 1.3/1,000 in 2002, but declined thereafter by 2009 to 0.8/1,000. There was a six-fold increase in the incidence rate in the age group 60–69 years and a ten-fold increase in the age group 70–79 years from 1987 to 2002. These marked increases in operation rates coincided with the increased use of tension-free vaginal tape (TVT). In 2002, TVT accounted for 96 % of all SUI procedures. Mid-urethral slings with transobturator techniques surpassed TVT in popularity in 2007. The life-long cumulative incidence of SUI surgery was 9.9 % in 2002 and 6.3 % in 2009.

Conclusions

The incidence rates of SUI surgery increased significantly in Finland, especially among women aged 60 to 79 years. Mid-urethral slings have become the dominant procedure.
  相似文献   
22.
23.
This study aimed to describe the psychiatric nursing care experiences of immigrant patients. The incidence of mental health problems is higher and the use of mental health services is lower among immigrants, especially refugees, compared with the majority of the population. The study uses a qualitative research approach, with an emphasis on focused ethnography research methods. The participants were immigrant patients (N = 14) residing in adult psychiatric wards of certain hospitals (N = 3) selected for the study. A majority of the participants were refugees or asylum seekers. A total of 21 in‐depth interviews were conducted. The experiences of these immigrant patients, both in their home countries and in their country of residence, had had an adverse effect on their mental health, with past traumatic experiences being the most central factor. Their symptoms included depression, anxiety, somatization, and psychosis. The findings show that the categories of factors that helped promote recovery among immigrant patients were nursing, medical treatment, care environment, and the patients' own methods. Based on the findings, a systematic evaluation of traumatic experiences is recommended for immigrants from countries with a history of war and/or political violence. Healthcare providers should also consider the importance of cultural desire in psychiatric nursing for the recovery of patients.  相似文献   
24.
Cytokinin signaling regulates cambial development in poplar   总被引:2,自引:0,他引:2       下载免费PDF全文
Although a substantial proportion of plant biomass originates from the activity of vascular cambium, the molecular basis of radial plant growth is still largely unknown. To address whether cytokinins are required for cambial activity, we studied cytokinin signaling across the cambial zones of 2 tree species, poplar (Populus trichocarpa) and birch (Betula pendula). We observed an expression peak for genes encoding cytokinin receptors in the dividing cambial cells. We reduced cytokinin levels endogenously by engineering transgenic poplar trees (P. tremula × tremuloides) to express a cytokinin catabolic gene, Arabidopsis CYTOKININ OXIDASE 2, under the promoter of a birch CYTOKININ RECEPTOR 1 gene. Transgenic trees showed reduced concentration of a biologically active cytokinin, correlating with impaired cytokinin responsiveness. In these trees, both apical and radial growth was compromised. However, radial growth was more affected, as illustrated by a thinner stem diameter than in WT at same height. To dissect radial from apical growth inhibition, we performed a reciprocal grafting experiment. WT scion outgrew the diameter of transgenic stock, implicating cytokinin activity as a direct determinant of radial growth. The reduced radial growth correlated with a reduced number of cambial cell layers. Moreover, expression of a cytokinin primary response gene was dramatically reduced in the thin-stemmed transgenic trees. Thus, a reduced level of cytokinin signaling is the primary basis for the impaired cambial growth observed. Together, our results show that cytokinins are major hormonal regulators required for cambial development.  相似文献   
25.
A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
26.
Food allergies (FAs) and hypersensitivities (FHSs) have rarely been studied in large unselected child populations. This population-based cross-sectional survey estimated the occurrence of FHS as perceived by parents and that of FA diagnosed by a physician among children aged 1–4 yr in south-eastern Finland. Before the scheduled annual follow-up visit to the local child health clinic, the parents of children who were born between 1 April, 2001 and 31 March, 2005, and living in the Province of South Karelia (data from Finnish Population Register) were mailed a questionnaire containing items on the child's background, physician-diagnosed FAs and FHSs perceived by the parents. The questionnaires were returned during the visit. Three thousand three hundred and eight (69%) out of the 4779 questionnaires were returned. The lifetime prevalence of physician-diagnosed FAs was 9%. In an additional 21%, FHSs were perceived by the parents only. In a further 19% at least one food item had been eliminated from the diet without any perception of symptoms, this proportion having a downward trend by age. Physician-diagnosed FAs were more common in boys than in girls. Cow's milk was the most commonly reported cause of food-associated symptoms (13% of all children). One-third of the children aged 1–4 yr suffered from food-associated symptoms, and in an additional fifth at least one food item had been eliminated from their diet, implying that every other child had possibly been subjected to some form of elimination diet.  相似文献   
27.
BackgroundSmoking and obesity are known risk factors for renal cell carcinoma (RCC). We determined the influence of smoking, body mass index (BMI), and symptoms on the survival of patients with RCC.Patients and MethodsIn this retrospective study, the relative overall survival (OS) up to 25 years was calculated among 948 Finnish patients with RCC diagnosed between 1964 and 1997 using a Bayesian univariate analysis and the life-table method.ResultsObese patients had better OS than did normal or underweight patients (median, 5.9 years, 3.4 years, and 12 months, respectively), with lower stage and more asymptomatic tumors at diagnosis and fewer relapses during surveillance. Clinical presentation of the tumor was a stronger prognostic factor than BMI; however, asymptomatic patients with a low BMI had poorer survival compared with normal or overweight patients. There was no difference in tumor stage or presentation at diagnosis between the nonsmokers and smokers; however, the smokers had more relapses with shorter disease-free intervals (DFIs) than did the nonsmokers. The OS was poorer in the smokers (4.2 years compared with 6.6 years in nonsmokers), but no difference was observed in cancer-specific survival (CSS).ConclusionOverweight patients have better survival, with more asymptomatic or local tumors. The clinical presentation was a stronger prognostic factor than BMI. Additionally, survival is poorer in smokers, even if there is no difference in tumor stage or symptoms.  相似文献   
28.
Occupational agents were evaluated for the risk of brain-nervous system cancer in a cohort of 413,877 Finnish women with blue-collar occupations in 1970. Observed and expected numbers of incident cases and the intensities of exposure to 25 agents were generated for 183 job titles from 1971 to 1995. Poisson regression models linked incidence and exposure data. Increased risks were found for medium/high intensities of iron (standardized incidence ratio [SIR], 2.15; 95% confidence interval [CI], 0.96 to 4.80), oil mist (1.95; 0.97 to 3.90), any chromium compounds (1.51; 0.85 to 2.67), electromagnetic fields (1.37; 0.98 to 2.10), aliphatic and alicyclic hydrocarbon compounds (1.34; 0.80 to 2.27), lead (1.27; 0.81 to 2.01), cadmium (1.26; 0.72 to 2.22), and aromatic hydrocarbon compounds (1.20; 0.71 to 2.03). Strengths of the study include fair number of cases, virtually complete case coverage, and a high-quality job exposure matrix. Ecological design and cross-sectional job assessment introduced exposure misclassification and tended to drive risk estimates toward unity.  相似文献   
29.
BACKGROUND: A simple empirically based method for assessment of the feasibility of workplace health promotion programs is described, focusing on cancer hazards (lifestyles, workplace hazards, deficient early detection). The basic components of feasibility are addressed: extent of hazards; needs of employees for hazard reduction and acceptability of WHP; and social context. METHODS: The procedure consists of six modules: guidelines on feasibility assessment; employee questionnaire; interview checklists for probing attitudes of management and partners (social context); data form; debriefing; and assessment of feasibility. Pretesting was completed in 16 workplace communities representing industry, construction, transport, telecommunications, health care, lodging and catering, teaching, and municipality jobs in five countries; a total of 1,085 subjects completed the employee questionnaire on health hazards, needs, and acceptability. RESULTS: The method demonstrated its utility in obtaining and summarizing the necessary data. Feasibility was assessed for the 16 test communities. CONCLUSION: The procedure can be customized; it has a high degree of face validity or understandability, and it is applicable in a wide variety of settings.  相似文献   
30.
Processing of changes in visual speech in the human auditory cortex   总被引:3,自引:0,他引:3  
Seeing a talker's articulatory gestures may affect the observer's auditory speech percept. Observing congruent articulatory gestures may enhance the recognition of speech sounds [J. Acoust. Soc. Am. 26 (1954) 212], whereas observing incongruent gestures may change the auditory percept phonetically as occurs in the McGurk effect [Nature 264 (1976) 746]. For example, simultaneous acoustic /ba/ and visual /ga/ are usually heard as /da/. We studied cortical processing of occasional changes in audiovisual and visual speech stimuli with magnetoencephalography. In the audiovisual experiment congruent (acoustic /iti/, visual /iti/) and incongruent (acoustic /ipi/, visual /iti/) audiovisual stimuli, which were both perceived as /iti/, were presented among congruent /ipi/ (acoustic /ipi/, visual /ipi/) stimuli. In the visual experiment only the visual components of these stimuli were presented. A visual change both in audiovisual and visual experiments activated supratemporal auditory cortices bilaterally. The auditory cortex activation to a visual change occurred later in the visual than in the audiovisual experiment, suggesting that interaction between modalities accelerates the detection of visual change in speech.  相似文献   
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