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   536篇
  免费   29篇
  国内免费   7篇
耳鼻咽喉   19篇
儿科学   36篇
妇产科学   36篇
基础医学   50篇
口腔科学   51篇
临床医学   50篇
内科学   100篇
皮肤病学   10篇
神经病学   29篇
特种医学   24篇
外科学   76篇
综合类   13篇
预防医学   18篇
眼科学   14篇
药学   33篇
肿瘤学   13篇
  2024年   1篇
  2023年   13篇
  2022年   15篇
  2021年   20篇
  2020年   14篇
  2019年   14篇
  2018年   18篇
  2017年   5篇
  2016年   23篇
  2015年   32篇
  2014年   30篇
  2013年   39篇
  2012年   46篇
  2011年   36篇
  2010年   18篇
  2009年   11篇
  2008年   31篇
  2007年   36篇
  2006年   43篇
  2005年   42篇
  2004年   28篇
  2003年   20篇
  2002年   20篇
  2001年   2篇
  1999年   1篇
  1998年   4篇
  1996年   3篇
  1995年   2篇
  1993年   2篇
  1992年   2篇
  1961年   1篇
排序方式: 共有572条查询结果,搜索用时 31 毫秒
71.
Inherited gene disorders related to the hemostatic system have been documented as risk factors for thrombosis. The roles of factor V Hong Kong (FV Hong Kong), factor V Leiden (FV Leiden), factor II G20210A (FII G20210A), methylenetetrahydrofolate reductase (MTHFR) C677T, and MTHFR A1298C mutations in Turkish patients with thrombosis (270 patients) compared with healthy controls (114 subjects) were evaluated. Polymerase chain reaction-based restriction enzyme analysis was carried out to screen these mutations, and single-strand conformation analysis was established to identify variations using the primers selected for restriction enzyme analysis studies. As a result, a significant relationship was determined among FV Leiden, FII G20210A, and thrombosis. The FV Hong Kong mutation was observed in only 2 patients with pulmonary vein thrombosis who are FV Leiden/FV Hong Kong compound heterozygous for FV gene. MTHFR C677T and A1298C were equally distributed in the patient group compared with the control group. All named mutations were also identified with single-strand conformation analysis, but a new variant/polymorphism during studies was not found. Because some inherited abnormalities are associated with thromboembolic disorders, determining the mutations and gene-to-gene interactions in patients with thrombosis history has a great impact on diagnosis and treatment of these diseases.  相似文献   
72.
Takayasu arteritis in children   总被引:1,自引:0,他引:1  
OBJECTIVE: To retrospectively evaluate the clinical features, angiographic findings, and outcomes of children with Takayasu arteritis (TA) in Turkey. METHODS: Clinical, laboratory, and angiographic findings and outcomes of 19 children with TA were evaluated with a retrospective chart review. The criteria for inclusion were those proposed by the American College of Rheumatology. RESULTS: Mean followup period was 35.89 +/- 40.75 months (range 1-168, median 30). There were 14 girls and 5 boys. The mean age at diagnosis was 12.84 +/- 2.69 years (range 8-17, median 13). The most common complaints on admission were headache (84%), abdominal pain (37%), claudication of extremities (32%), fever (26%), and weight loss (10%). One patient presented with visual loss. Examination on admission revealed hypertension (89%), absent pulses (58%), and bruits (42%). Angiography revealed type I in 13 patients (aortic arch, descending thoracic, and abdominal aorta), type II in 4 (descending thoracic aorta and abdominal aorta), and type IV in 2 (diffuse aortic and pulmonary artery). The most commonly involved vessels were the renal, subclavian, and carotid arteries. All patients received corticosteroid therapy, and further immunosuppressive therapy was added in 15 patients. Fourteen of the 17 hypertensive patients had renal artery stenosis and 9 underwent surgery or interventional therapy. Thoraco-abdominal bypass graft was performed in 2 patients who had abdominal aortic stenosis. CONCLUSION: Hypertension is the most common clinical feature at presentation. Corticosteroid and immunosuppressive therapy was effective in the control of disease activity. Angioplasty or bypass grafting was successfully performed when needed.  相似文献   
73.

Background/Aim:

Adult studies established a relationship between hepatitis C virus (HCV) infection and the presence of non–organ-specific antibodies (NOSAs). Most studies were carried out on genotypes 1 and 2. Only a few studies addressed that issue in pediatrics. No studies have been carried out on autoimmunity and genotype 4 in children. We aim to investigate NOSAs in 80 Egyptian children with chronic HCV infection along with studying the underlying genotype of HCV, and correlating autoimmunity with the epidemiological, clinical, biochemical, and virological features.

Materials and Methods:

HCV-RNA was assayed by the polymerase chain reaction and viral genotypes were determined. NOSAs were measured and liver biopsies were taken for histopathological examination.

Results:

Genotype4 was the only detected genotype in the included 80 patients. Anti-smooth muscle antibodies (ASMA) were the only detected antibodies in 32 (40%) patients, always with V specificity (vessels only) at titers ranging from 1:20 and 1:160. Anti-nuclear antibodies (ANA) and liver–kidney microsomal antibodies-1 (LKMA-1) were not detected in any of our patients. Epidemiologic and clinical features did not significantly differ between autoantibody-positive and -negative patients. Among biochemical features, significantly high levels of total bilirubin, albumin, immunoglobulins, alkaline phosphatase, and gamma-glutamyl transpeptidase were found in the antibody-positive group.

Conclusion:

Genotype 4 HCV is the prevailing genotype in Egyptian children with chronic HCV infection. A consistent proportion of these children with chronic HCV infection circulate non–organ-specific autoantibodies. The prevalence of ASMA and the absence of ANA and LKMA-1 might be related to the unique situation in Egypt with unique prevalence of genotype 4. More studies are warranted on larger pediatric population to validate these findings.  相似文献   
74.
Leptin, the obese gene product, is a 16-kDa peptide hormone secreted by adiposities. Systemic administration of exogenous glucocorticoids has been found to increase circulating leptin levels. In this study, we aimed to assess serum leptin in children with atopic dermatitis (AD)-treated with local steroids. Twenty children with AD were included during the 2001-2002 time period. The study was conducted prospectively. Atopy was defined as the presence of at least one aeroallergen-specific immunoglobulin E (IgE) antibody. Serum leptin was determined using a commercially available radioimmunoassay kit with 3.4-8.3% intra-assay and 3.0-6.2% interassay coefficients of variation, and 0.5 ng/ml sensitivity. Fourteen boys and six girls with AD, the mean age of the patients was 3.1 +/- 2.2. Forty-three percentage of the family histories for atopy were positive, 60% of the cases passive smoking histories were positive. In seven patients the aeroallergen-specific IgE were positive. All 20 patients treated clobetasone 17-butirate (0.05%). There was no significant difference in serum leptin between patients (mean +/- s.d.: 4.6 +/- 3.8), and controls (mean +/- s.d.: 6.2 +/- 3.6) (p > 0.05). Local steroid does not influence circulating leptin levels, suggesting that regulation of body weight is unaffected.  相似文献   
75.
Several vascular carriers for different tissues were used for the purpose of fat tissue prefabrication. However, the inguinal fat pad in rats can be elevated with a vascular pedicle and considered as a vascular carrier. To the best of our knowledge, the fat tissue in rats as a vascular carrier has not been reported in any experimental studies to date. In our study, we aimed to describe a new prefabrication model in rats in which skin prefabrication was accomplished using the inguinal fat pad as a vascular carrier. Inguinal fat pads in rats were elevated over a superficial epigastric vessel pedicle in the pilot study. The contralateral inguinal fat pads were prepared as grafts. After 1 week, we compared the histopathological findings of the inguinal fat pad flaps and grafts and determined that the inguinal fat pad can be safely elevated over the vascular pedicle. In the experimental group, bilateral vascularised inguinal fat pads were transferred to the lower abdomen for skin prefabrication. After 3 weeks, bilateral fat-skin composite flaps including prefabricated lower abdomen skin were elevated over the vascular pedicles. One side was used as a composite flap while pedicle of the other side was transected at its origin at the femoral vessels to create the composite graft. Composite flap and graft were inserted at their original positions. One week later, the composite flaps were stained with India ink, perfused by fluorescein, and filled with contrast material for microangiographic study. In the histological examination, fat and skin tissues of the composite flaps were viable while those of the composite grafts were necrotic. Based on these findings, we can conclude that the fat tissue as a vascular carrier can be successfully used for tissue prefabrication in plastic surgery.  相似文献   
76.
M475271, 4-quinazolinamine, N-(2-chloro-5-methoxyphenyl)-6-methoxy-7-[(1-methyl-4-piperidinyl) methoxy]-(9Cl), is a new anilinoquinazoline derivative that displays selective inhibition of Src kinase activity and tumor growth in vivo. Vascular endothelial growth factor (VEGF)-induced angiogenesis plays a pivotal role in tumor growth and metastasis. Vascular endothelial (VE)-cadherin is an endothelial cell-specific adhesion molecule that can interact with the cytoskeleton via several anchoring molecules such as beta-catenin. Here, we examined the effect of M475271 on VE-cadherin and beta-catenin phosphorylation and association. We also examined its effect on VEGF-induced human umbilical vein endothelial cell (HUVEC) proliferation, migration, and tube formation. The findings reveal pretreatment with M475271 significantly inhibits VEGF-induced VE-cadherin and beta-catenin phosphorylation. However, M475271 significantly increases VE-cadherin and beta-catenin association compared to the VEGF-treated group. Confocal laser microscopic examination confirmed the augmentation effect of M475271 on VE-cadherin and beta-catenin association. Finally, M475271 was shown to have inhibitory effects comparable to those of PP2 and Herbimycin A on VEGF-induced HUVEC proliferation, migration, and tube formation. These findings suggest that M475271 attenuates VEGF-induced angiogenesis by maintaining cell-cell junction stability. Although the involvement of other signaling molecules cannot be ruled out, M475271 has potential as a drug for the inhibition of the angiogenesis needed for tumor growth and metastasis.  相似文献   
77.
OBJECTIVES: To investigate the relationship between language functions and cognitive and functional outcome and to evaluate the effects of a conventional language rehabilitation programme on aphasic adult patients in the post-acute stage of traumatic brain injury (TBI). DESIGN: Non-concurrent prospective study. Patients were assessed pre-treatment and post-treatment with standardized assessment tools. SUBJECTS: Sixty-one aphasic patients with TBI who were admitted to a rehabilitation centre in the post-acute phase for a late inpatient rehabilitation programme. METHODS: The motor sub-scales of the Functional Independence Measures and Disability Rating Scale were used to assess functional status and disability. Cognitive status was evaluated with the Mini-Mental Status Examination and the Functional Independence Measure cognitive sub-scale. The language function was evaluated with the Gülhane Aphasia Test. RESULTS: All functional, cognitive and language scores increased significantly during the rehabilitation programme. Language functions at admission were correlated with the Functional Independence Measure motor change scores and the Mini-Mental Status Examination change scores. Regression analyses revealed that auditory comprehension at admission was the most important independent determinant of functional and cognitive gain during rehabilitation. CONCLUSION: Post-acute language functions after late admission to a rehabilitation centre appear to be related to measures of cognitive and functional progress in patients with TBI. Functional and cognitive outcome is mainly affected by auditory comprehension. Results also showed the effectiveness of post-acute conventional rehabilitation in improving language functions.  相似文献   
78.
In the past decades, cases of canine ocular onchocercosis have been reported worldwide, particularly in the United States and Europe. Onchocerca lupi, originally described from a wolf, has been implicated in some of these cases, and its zoonotic role has been hypothesized on the basis of the reexamination of two cases of human ocular onchocerciasis. In the present study, we describe, for the first time, the occurrence of O. lupi in the subconjunctival region of the human eye in a patient from Turkey. The nematode was identified as O. lupi based on its morphology and molecular phylogenetic analysis of partial cox1 and 12S ribosomal DNA genes. The results suggest that O. lupi should be considered in the differential diagnosis of other eye parasitic infections in humans. The role of dogs as natural hosts of O. lupi and the vectors of this zoonotic parasite need to be investigated.  相似文献   
79.
80.
The aim of this study was to investigate a tularemia outbreak in the Thrace region of Turkey. The outbreak occurred in Demirkoy village of Edirne, in 2005. Of 400 villagers, 266 were examined and their sera were taken. Throat swabs and lymph node aspirates were cultured. Specific antibodies in patients and domestic animals were screened by a microagglutination test. PCR assays and cultures of the samples of patients, animal tissues, and water sources were performed, along with active surveillance to identify risk factors. Seven out of 10 cases were diagnosed as oropharyngeal form; the remaining three patients were asymptomatic. The cultures for tularemia were negative; however, PCR assays were positive in one lymph node aspirate and in water from one spring. Some animals had the specific antibody at low levels. Increased rodent population in the vicinity, exposure to wild rabbits, and drinking from one of the springs were identified as risk factors with the risk ratios (and 95% confidence interval) of 10.5 (10.3-10.7), 6.5 (5.43-7.57), and 2.1 (1.1-2.5), respectively. Therapeutic and preventive measures were taken. When tularemia cases have been detected in a region even a few decades earlier, tularemia should be considered in the differential diagnosis of patients.  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