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   99篇
  免费   9篇
耳鼻咽喉   7篇
儿科学   5篇
妇产科学   1篇
基础医学   10篇
口腔科学   8篇
临床医学   4篇
内科学   17篇
神经病学   19篇
特种医学   7篇
外科学   17篇
预防医学   7篇
药学   4篇
肿瘤学   2篇
  2023年   2篇
  2022年   1篇
  2021年   4篇
  2020年   4篇
  2019年   5篇
  2018年   13篇
  2017年   3篇
  2016年   9篇
  2015年   7篇
  2014年   6篇
  2013年   3篇
  2012年   13篇
  2011年   4篇
  2010年   4篇
  2009年   1篇
  2008年   8篇
  2007年   2篇
  2006年   2篇
  2005年   5篇
  2003年   2篇
  2001年   1篇
  1987年   2篇
  1986年   2篇
  1985年   3篇
  1984年   2篇
排序方式: 共有108条查询结果,搜索用时 62 毫秒
1.
Increased carotid atherosclerosis in andropausal middle-aged men   总被引:2,自引:0,他引:2  
OBJECTIVES: This study examined the association between carotid artery intima-media thickness (IMT), serum sex hormone levels, and andropausal symptoms in middle-aged men. BACKGROUND: Male sex hormones may play a dual role in the pathogenesis of atherosclerosis in men by carrying both proatherogenic and atheroprotective effects. METHODS: We studied 239 40- to 70-year-old men (mean +/- SD: 57 +/- 8 years) who participated in the Turku Aging Male Study and underwent serum lipid and sex hormone measurements. Ninety-nine men (age 58 +/- 7 years) were considered andropausal (i.e., serum testosterone <9.8 nmol/l or luteinizing hormone [LH] >6.0 U/l and testosterone in the normal range), and in both situations, they had subjective symptoms of andropause (a high symptom score in questionnaire). Three were excluded because of diabetes. The rest of the men (age 57 +/- 8 years) served as controls. Carotid IMT was determined using high-resolution B-mode ultrasound, and serum testosterone, estradiol (E2), LH, and sex hormone-binding globulin were measured using standard immunoassays. RESULTS: Andropausal men had a higher maximal IMT compared with controls in the common carotid (1.08 +/- 0.34 vs. 1.00 +/- 0.23, p < 0.05) and in the carotid bulb (1.44 +/- 0.48 vs. 1.27 +/- 0.35, p = 0.003). Common carotid IMT correlated inversely with serum testosterone (p = 0.003) and directly with LH (p = 0.006) in multivariate models adjusted for age, total cholesterol, body mass index, blood pressure, and smoking. CONCLUSIONS: Middle-aged men with symptoms of andropause, together with absolute or compensated (as reflected by high normal to elevated LH) testosterone deficiency, show increased carotid IMT. These data suggest that normal testosterone levels may offer protection against the development of atherosclerosis in middle-aged men.  相似文献   
2.
Nature offers exciting examples for functional wetting properties based on superhydrophobicity, such as the self-cleaning surfaces on plant leaves and trapped air on immersed insect surfaces allowing underwater breathing. They inspire biomimetic approaches in science and technology. Superhydrophobicity relies on the Cassie wetting state where air is trapped within the surface topography. Pressure can trigger an irreversible transition from the Cassie state to the Wenzel state with no trapped air--this transition is usually detrimental for nonwetting functionality and is to be avoided. Here we present a new type of reversible, localized and instantaneous transition between two Cassie wetting states, enabled by two-level (dual-scale) topography of a superhydrophobic surface, that allows writing, erasing, rewriting and storing of optically displayed information in plastrons related to different length scales.  相似文献   
3.
This study investigates the correlation between the composition of human meniscus and its absorption spectrum in the visible (VIS) and near infrared (NIR) spectral range. Meniscus samples (n = 24) were obtained from nonarthritic knees of human cadavers with no history of joint diseases. Specimens (n = 72) were obtained from three distinct sections of the meniscus, namely; anterior, center, posterior. Absorption spectra were acquired from each specimen in the VIS and NIR spectral range (400–1,100 nm). Following spectroscopic probing, the specimens were subjected to biochemical analyses to determine the matrix composition, that is water, hydroxyproline, and uronic acid contents. Multivariate analytical techniques, including principal component analysis (PCA) and partial least squares (PLS) regression, were then used to investigate the correlation between the matrix composition and it spectral response. Our results indicate that the optical absorption of meniscus matrix is related to its composition, and this relationship is optimal in the NIR spectral range (750–1,100 nm). High correlations (R2uronic = 86.9%, R2water = 83.8%, R2hydroxyproline = 81.7%, p < 0.0001) were obtained between the spectral predicted and measured meniscus composition, thus suggesting that spectral data in the NIR range can be utilized for estimating the matrix composition of human meniscus. In conclusion, optical spectroscopy, particularly in the NIR spectral range, is a potential method for evaluating the composition of human meniscus. This presents a promising technique for rapid and nondestructive evaluation of meniscus integrity in real‐time during arthroscopic surgery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:270–278, 2016.  相似文献   
4.
Objective:To investigate the association between satisfaction with dental esthetics and quality of life, and esthetics satisfaction in relation to esthetic evaluations of three panel groups.Materials and Methods:Fifty-two patients (36 women, 16 men; age 18–61 years) with severe malocclusion were treated in Oulu University Hospital. Of these, 38 and 14 patients underwent orthodontic/surgical treatment and orthodontic treatment, respectively. A questionnaire and dental photographs were collected before and after treatment. The 14-item Oral Health Impact Profile (OHIP-14) was used to measure oral health-related quality of life. Satisfaction with dental esthetics was evaluated using the Visual Analogue Scale. Dental photographs were presented to three panel groups: 30 laypersons, 30 dental students, and 10 orthodontists, who rated the photographs using the Aesthetic Component of the Index of Orthodontic Treatment Need.Results:Oral health–related quality of life (OHIP-14 severity score) and esthetic satisfaction (according to the Visual Analogue Scale) improved after the treatment (P < .001). The most unsatisfied patients reported oral effects more often both before and after treatment. Changes in oral health–related quality of life components of severity, psychological discomfort, and psychological disability correlated positively with the changes in esthetic satisfaction. Orthodontists graded the situation before treatment as worse and the outcome as better than the laypersons; the level of grading by dental students fell between these two groups.Conclusion:Improvement in esthetic satisfaction due to the treatment of severe malocclusion improves oral health–related quality of life, particularly by decreasing psychological discomfort and psychological disability.  相似文献   
5.
6.
A comparative scanning electron microscopical study on the topical effects of glucocorticoids on rat knee cartilage was undertaken. Water-soluble and crystalloid 'depot'-form glucocorticoids were tested. Cartilage destruction was dependent on the number of injections and was clearly more pronounced in the knees injected with crystalloid glucocorticoid. We conclude that repeated injection of the joint with glucocorticoids should be given only after careful consideration of the clinical state.  相似文献   
7.
8.

Introduction

Recently two classification methods based on the location and the extent of thrombosis detected with CT angiography have been introduced: the Boston Acute Stroke Imaging Scale (BASIS) and the clot burden score (CBS). We studied the performance of BASIS and CBS in predicting good clinical outcome (mRS ≤2 at 90?days) in an acute (<3?h) stroke cohort treated with intravenous thrombolytic therapy.

Methods

Eighty-three consecutive patients who underwent multimodal CT were analyzed. Binary logistic regression model was used to assess how BASIS, CBS, and cerebral blood volume (CBV) ASPECTS predict favorable clinical outcome. Diagnostic sensitivities and specificities were calculated and compared.

Results

Patients with low CBS and CBV ASPECTS scores and major strokes according to BASIS had significantly higher admission NIHSS scores, larger perfusion defects, and more often poor clinical outcome. In logistic regression analysis, CBV ASPECTS, CBS and BASIS were significantly associated with the clinical outcome. The performance of BASIS improved when patients with thrombosis of the M2 segment of the middle cerebral artery were classified as having minor stroke (M1-BASIS). In the anterior circulation, the sum of CBS and CBV ASPECTS (CBSV) proved to be the most robust predictor of favorable outcome. CBV ASPECTS and CBS had high sensitivity but moderate to poor specificity while BASIS was only moderately sensitive and specific.

Conclusion

CBS, BASIS, and CBV ASPECTS are statistically robust and sensitive but unspecific predictors of good clinical outcome. Two new derived imaging parameters, CBSV and M1-BASIS, share these properties and may have increased prognostic value.  相似文献   
9.

Introduction

Perfusion computed tomography (PCT) is increasingly performed in multimodal CT evaluation of acute ischemic stroke. We compared the technical quality of perfusion studies performed with a 16-row and a 64-row scanner and analyzed the differences between the scanners in their ability to detect perfusion defects.

Methods

We analyzed retrospectively the clinical and imaging data of 140 consecutive acute (<3?h) stroke patients who underwent multimodal CT evaluation and received intravenous rtPA. Alberta Stroke Program Early CT Score (ASPECTS) was assigned to PCT maps. Clinical and imaging parameters were compared between the two scanners.

Results

There were more motion artifacts in the 16-row studies (p?=?0.04), and the analysis software was able to completely correct significantly fewer of these (p?p?p?=?0.02). The 64-row scanner was able to detect more perfusion defects that were located entirely outside the ASPECTS regions (p?=?0.03). There was no significant difference in the 3-month functional outcome.

Conclusions

The 16-row scanner suffered from limited anatomic coverage that decreased the sensitivity to detect perfusion defects in the cranial parts of the middle cerebral artery region. The 16-row studies had poorer technical quality that was in part attributable to higher sampling frequency and smaller slice thickness making the imaging more sensitive to small-scale movement of the patient.  相似文献   
10.

Objectives

To evaluate the association of self-reported health with residential area type defined by the population density in individual??s local environment using a population-based cohort in Finland.

Methods

Young adults of the Northern Finland Birth Cohort 1966 (4,201 women and 3,835 men), surveyed by a postal questionnaire in 1997, were linked to population density of their resident grid (1?km2) depicting different types of residential areas. Self-reported health was regressed on residential area type using ordinal logistic analysis, adjusting for psychosocial well-being, social relationships, health behaviour, education and residence time.

Results

Cumulative odds ratios (COR) for poor health were lowest in high-rise centres, highest in scattered settlement areas and second highest in transitional zones. Adjustments (especially for education and time of residence) reduced the CORs to insignificance except the persistently high COR for women in scattered settlement areas.

Conclusion

Poor self-reported health is associated with individual??s residential area type, with the lowest occurrence in high-rise centres and higher elsewhere. The difference is likely explained, at least partly, by a complex of psychosocial factors, possibly different for women and men.  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