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   1102篇
  免费   83篇
  国内免费   3篇
  2023年   10篇
  2022年   3篇
  2021年   34篇
  2020年   15篇
  2019年   17篇
  2018年   27篇
  2017年   28篇
  2016年   44篇
  2015年   74篇
  2014年   69篇
  2013年   84篇
  2012年   120篇
  2011年   111篇
  2010年   73篇
  2009年   51篇
  2008年   82篇
  2007年   69篇
  2006年   52篇
  2005年   40篇
  2004年   48篇
  2003年   35篇
  2002年   27篇
  2001年   9篇
  2000年   4篇
  1999年   5篇
  1998年   6篇
  1997年   6篇
  1996年   1篇
  1995年   4篇
  1994年   1篇
  1993年   6篇
  1992年   5篇
  1991年   2篇
  1990年   5篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1986年   1篇
  1984年   1篇
  1983年   3篇
  1982年   5篇
  1981年   3篇
  1980年   1篇
  1973年   1篇
  1972年   1篇
  1937年   1篇
排序方式: 共有1188条查询结果,搜索用时 46 毫秒
101.
Patients who are already diagnosed with cutaneous melanoma are at increased risk of developing another primary melanoma. The occurrence of multiple primary melanoma is a rare phenomenon, varying in frequency, with an estimated incidence ranging from 0.2% to 8.6%. The authors are presenting data on the patients with multiple primary melanoma from the Croatian Referral Melanoma Centre. The clinical, histological and epidemiological characteristics of 36 (3.6%) patients, identified from 991 patients with histologically confirmed melanoma, are analyzed in this study. Twenty-eight of the patients (78%) had two primary melanomas, six had three melanomas (16.7%) and two (5,6%) had four melanomas. Diagnosis was established synchronously in 11 patients (30%) and, in the rest of the patients, time interval between the diagnosis of the first and second melanoma varied from 1 month to the longest interval of 16 years. However, the majority of subsequent melanomas were removed within 2 years of the initial operation. The mean Breslow's thickness of the first melanoma was significantly higher than the mean Breslow's thickness of the second primary melanoma. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Therefore, we emphasize the importance of regular follow-up as well as the education in regular self--skin examinations in melanoma patients in order to detect subsequent primary melanomas in the early phase.  相似文献   
102.
The study aimed to establish the frequency of injuries in primary and secondary schools during leisure time and physical education classes in school as well as in group and individual sports. The sample included 2842 pupils from nine primary schools and 1235 students from five secondary schools in Slovenia. The data were processed with the SPSS statistical software package and the frequencies and Crosstabs were calculated. The results showed that substantially more pupils and students were injured in their leisure time than during physical education classes. Girls were more frequently injured in group and individual sports practiced during physical education classes and in individual sports practiced in their leisure time, whereas boys suffered more injuries in group sports practiced in their leisure time. As regards group sports, pupils and students were most frequently injured while playing football in their leisure time whereas, during physical education classes, they suffered most injuries in volleyball, followed closely by basketball and football; as regards individual sports, pupils and students were most frequently injured while cycling and rollerblading in their leisure time, whereas during physical education classes they suffered most injuries in athletics.  相似文献   
103.
The loss of the corneal endothelial cells, especially in a first postoperative year, has been observed in patients who underwent penetrating keratoplasty (PK). The implantation of new generation of "iris claw" phakic IOL (Verisyse) in refractive cases has been shown to cause clinicaly insignificant endothelial cell loss. In our prospective case series we investigated the endothelial cell loss and clinical outcome in patients that either underwent PK and implantation of PCIOL or PK and implantation of Verisyse IOL. In the first group of 9 patients scheduled for PK, implantation of Verisyse was performed due to the absence of the posterior capsule support. 2 of these patients had angle supported ACIOL, 4 patients were aphakic and 3 had posttraumatic cataract with ruptured posterior capsule. The second group of 12 patients had standard "triple" procedure (PK + ECCE + PCIOL). BCVA of both groups of patients prior the operation was hand movement in 12 patients, light perception in 7 patients and 0.05 in 3 patients. The preoperative endothelial cell count of the donor grafts obtained from the eye bank was 2800 cells/mm2 on average. The follow up was 6-10 months. Six months after the operation all "Verysise" patients maintained transparent graft. Postoperative visual acuity improvement was recorded in 18 out of 21 eyes (85.7%). Best spectacle corrected visual acuity of > or = 0.3 was achived in 55.5% in the Verisyse group and in 50.0% of "triple procedure" group. The endothelial cell count and morphology were estimated on the specular microscope on a monthly basis. Mean endothelial cells loss in patients with PK and Verysise was 40 +/- 8% and in patients with "triple" procedure was 42 +/- 12% at 10 postoperative months. There was no significant difference in the endothelial cell loss and clinical outcome between the group of patients who had PK and Verysise as compared to those with implanted PCIOL.  相似文献   
104.
The aim of this study is to evaluate pseudoexfoliative glaucoma (PEX) in Primorsko-Goranska County, Croatia, and its characteristics comparing to primary open angle glaucoma (POAG). In the study a hundred patients with open angle glaucoma were examined, twenty six of them had a pseudoexfoliative glaucoma diagnosed. We were following intraocular pressure (IOP) values, visual acuities, visual fields and optical nerve head changes retrospectively. Comparing to primary open angle glaucoma pseudoexfoliative glaucoma in Primorsko-Goranska County has less good prognosis because the IOP is usually higher and more difficult to control, we found progressive loss of retinal ganglion cells and visual field loss develop more rapidly. Because of that pseudoexfoliative glaucoma requires special treatment and following.  相似文献   
105.
Secondary chronic open-angle glaucoma associated with pseudoexfoliation (PEX) syndrome accounts for approximately 25% of all glaucomas and represents the most common identifiable cause of glaucoma overall. Selective laser trabeculoplasty (SLT) is effective in reducing intraocular pressure (IOP) in glaucomatous patients and has the advantage of preserving surrounding structures. We report here SLT treatment of a 82 year old female with a secondary developed open-angle pseudoexfoliation glaucoma allergic to all anti glaucoma eye drops especially those which contain bensalconium chloridum as preservative. Since patient was allergic also to methyl-cellulose, we performed SLT with water as a mediator. Patient had PEX syndrome for 10 years, immature cataracts on both eyes, and best corrected visual acuity (BCVA) 0.7 on the right and 0.2 on the left eye. We have monitored intraocular pressure (IOP), the changes in the visual field and optic nerve. Preoperative IOP was 28 mmHg on the right and 30 mmHg on the left eye. The follow up period was 24 months with time points for measured parameters every 3 months. After 18 months IOP remained in the normal values (average 17 mmHg) on the right eye, but on the left eye it increased up to 28 mmHg. SLT re-treatment was carried out on the left eye and the IOP stabilized again on the values between 16-18mmHg. There were no significant change in the visual field and optic nerve configuration before and after SLT (C/D value for right eye: 0.3-0.4; C/D left eye: 0.5). Based on this case report, SLT seems to be very effective treatment for maintaining regular IOP in patient with PEX who is allergic to all types of medications.  相似文献   
106.
The endothelial cells are one of the most important structures in a donor cornea. Morphology and concentration of endothelial cells must be carefully evaluated with a specular microscope before transplantation. The aim of this study is to evaluate the status of corneal endothelium in glaucoma patients. Prospective study included 50 patients suffering from glaucoma and 50 patients in control group. Patients had no corneal disease, ocular inflammation, previous trauma or ocular surgery. Patients were not contact lens wearers. They were also analyzed in groups according to type of glaucoma. Specular microscopy was performed on central corneas. This study showed that patients with glaucoma have lower central corneal endothelial cell density than those without glaucoma of the same age group. Also, patients with pseudoexfoliative glaucoma had lower values of central endothelial cell density comparing to patients with open angle or angle closure glaucoma.  相似文献   
107.
Wing length is a key character for essential behaviours related to bird flight such as migration and foraging. In the present study, we initiate the search for the genes underlying wing length in birds by studying a long-distance migrant, the great reed warbler (Acrocephalus arundinaceus). In this species wing length is an evolutionary interesting trait with pronounced latitudinal gradient and sex-specific selection regimes in local populations. We performed a quantitative trait locus (QTL) scan for wing length in great reed warblers using phenotypic, genotypic, pedigree and linkage map data from our long-term study population in Sweden. We applied the linkage analysis mapping method implemented in GridQTL (a new web-based software) and detected a genome-wide significant QTL for wing length on chromosome 2, to our knowledge, the first detected QTL in wild birds. The QTL extended over 25 cM and accounted for a substantial part (37%) of the phenotypic variance of the trait. A genome scan for tarsus length (a body-size-related trait) did not show any signal, implying that the wing-length QTL on chromosome 2 was not associated with body size. Our results provide a first important step into understanding the genetic architecture of avian wing length, and give opportunities to study the evolutionary dynamics of wing length at the locus level.  相似文献   
108.
109.
Multiple sclerosis (MS) is an inflammatory neurodegenerative disease of the CNS. Recent advances in whole-genome screening tools have enabled discovery of several MS risk genes, the majority of which have known immune-related functions. However, disease heterogeneity and low tissue accessibility hinder functional studies of established MS risk genes. For this reason, the MS model experimental autoimmune encephalomyelitis (EAE) is often used to study neuroinflammatory disease mechanisms. In this study, we performed high-resolution linkage analysis in a rat advanced intercross line to identify an EAE-regulating quantitative trait locus, Eae29, on rat chromosome 1. Eae29 alleles from the resistant strain both conferred milder EAE and lower production of proinflammatory molecules in macrophages, as demonstrated by the congenic line, DA.PVG-Eae29 (Dc1P). The soluble IL-22R α2 gene (Il-22ra2) lies within the Eae29 locus, and its expression was reduced in Dc1P, both in activated macrophages and splenocytes from immunized rats. Moreover, a single nucleotide polymorphism located at the end of IL-22RA2 associated with MS risk in a combined Swedish and Norwegian cohort comprising 5019 subjects, displaying an odds ratio of 1.26 (p = 8.0 × 10(-4)). IL-22 and its receptors have been implicated in chronic inflammation, suggesting that IL-22RA2 regulates a central immune pathway. Through a combined approach including genetic and immunological investigation in an animal model and large-scale association studies of MS patients, we establish IL-22RA2 as an MS risk gene.  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