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   1917篇
  免费   127篇
  国内免费   4篇
耳鼻咽喉   12篇
儿科学   127篇
妇产科学   40篇
基础医学   288篇
口腔科学   13篇
临床医学   139篇
内科学   496篇
皮肤病学   94篇
神经病学   48篇
特种医学   46篇
外科学   127篇
综合类   115篇
一般理论   1篇
预防医学   132篇
眼科学   35篇
药学   147篇
中国医学   12篇
肿瘤学   176篇
  2023年   9篇
  2022年   25篇
  2021年   36篇
  2020年   24篇
  2019年   33篇
  2018年   46篇
  2017年   27篇
  2016年   51篇
  2015年   60篇
  2014年   84篇
  2013年   86篇
  2012年   142篇
  2011年   174篇
  2010年   113篇
  2009年   60篇
  2008年   112篇
  2007年   117篇
  2006年   98篇
  2005年   95篇
  2004年   100篇
  2003年   100篇
  2002年   80篇
  2001年   32篇
  2000年   48篇
  1999年   37篇
  1998年   17篇
  1997年   11篇
  1996年   18篇
  1995年   17篇
  1994年   4篇
  1993年   8篇
  1992年   23篇
  1991年   24篇
  1990年   11篇
  1989年   15篇
  1988年   15篇
  1987年   15篇
  1986年   12篇
  1985年   7篇
  1984年   6篇
  1983年   6篇
  1982年   7篇
  1981年   3篇
  1979年   7篇
  1978年   5篇
  1976年   3篇
  1975年   3篇
  1960年   2篇
  1956年   2篇
  1950年   2篇
排序方式: 共有2048条查询结果,搜索用时 0 毫秒
71.
New Strategies for Colorectal Cancer Prevention and Treatment   总被引:4,自引:0,他引:4  
Colorectal cancer (CRC) is the second most common fatal malignancy in the Western world, with more than 150,000 new cases accounting for 55,000 deaths in the United States every year. Surgical resection is an effective treatment for localized disease, achieving a 5-year survival rate of 90%; but chemotherapy and other novel treatments for metastatic disease remain ineffective. There have been significant efforts to identify risk factors associated with the development of CRC and to explore potential preventive therapies. Both genetic and epigenetic factors contribute to the development of colorectal cancer. Specific genetic changes in proto-oncogenes, tumor suppressor genes, and DNA mismatch repair genes have led to a genetic model of CRC. Cooperative genetic aberrations involving APC (adenomatous polyposis coli), beta-catenine, K-ras, and p53 are involved in the multistep adenoma-carcinoma sequence of CRC. Emerging data have implicated cyclooxygenase-2 (COX-2) and prostanoid production in the pathogenesis of colorectal carcinoma. Several reports indicate a close relation between the intake of nonsteroidal antiinflammatory drugs (NSAIDs) and a decreased risk for developing colorectal cancer. Epidemiologic studies indicate a 40% to 50% reduction in mortality due to colorectal cancer in individuals taking NSAIDs (e.g., aspirin). Epigenetic factors including age, diet, angiogenesis, and immune responses also appear to contribute to the development of CRC. Combining knowledge of the genetic and epigenetic events implicated in this disease may allow a broader understanding of the pathogenesis of CRC. These developments may yield benefits in earlier detection and in the design of better antitumor interventions.  相似文献   
72.
73.
SARS-CoV-2/influenza virus co-infection studies have focused on hospitalized patients who usually had grave sequelae. Here, we report SARS-CoV-2/influenza virus co-infection cases from both community and hospital settings reported through integrated ILI/SARI (Influenza Like Illness/Severe Acute Respiratory Infection) sentinel surveillance established by the Indian Council of Medical Research. We describe the disease progression and outcomes in these cases. Out of 13,467 samples tested from 4 July 2021–31 January 2022, only 5 (0.04%) were of SARS-CoV-2/influenza virus co-infection from 3 different sites in distinct geographic regions. Of these, three patients with extremes of age required hospital admission, but none required ICU admission or mechanical ventilation. No mortality was reported. The other two co-infection cases from community settings were managed at home. This is the first report on SARS-CoV-2/Influenza virus co-infection from community as well as hospital settings in India and shows that influenza viruses are circulating in the community even during COVID-19. The results emphasize the need for continuous surveillance for multiple respiratory pathogens for effective public health management of ILI/SARI cases in line with the WHO (World Health Organization) recommendations.  相似文献   
74.
75.
Inflammation Research - IL-6-induced STAT3 activation is associated with various chronic inflammatory diseases. In this study, we investigated the anti-STAT3 mechanism of the dietary polyphenol,...  相似文献   
76.
Nevus lipomatosus cutaneous superficialis (NLCS) is a benign dermatosis, histologically characterized by the presence of mature ectopic adipocytes in the dermis. We hereby report a case of a 10-year-old boy who presented with multiple huge swellings on the scapular regions and lower back. The lesions were surmounted by small papules, along with peau-d orange appearance at places. Histology showed features consistent with NLCS. The case is being reported for the unusual clinical presentation.  相似文献   
77.
Heart Failure Reviews - Heart failure is a global health burden responsible for high morbidity and mortality with a prevalence of greater than 60 million individuals worldwide. One of the major...  相似文献   
78.
Primary hyperparathyroidism (PHPT) is extremely uncommon among children and is more likely to be associated with genetic syndromes, multiglandular involvement, and more severe symptoms. Rickets can very rarely be the presenting feature of PHPT in children. Rickets was diagnosed in a 12-year-old girl presenting with short stature, genu valgum, eversion deformity at the ankle joints, and flat feet. Radiograms showed generalized osteopenia, widening of the distal ends of the long bones along with splaying, cupping and fraying. Biochemical evaluation revealed low serum calcium (7.8 mg/dL), low phosphorus (1.4 mg/dL), vitamin-D deficiency [25-hydroxy-vitamin-D (25(OH)D): 8.7 ng/mL], and elevated intact parathyroid hormone (PTH, 811 pg/mL). Re-evaluation due to lack of clinical improvement following vitamin-D and calcium supplementation revealed hypercalcemia 11.9 mg/dL, normal 25(OH)D 41 ng/mL, persistence of elevated PTH 632 pg/mL. A 99mTc-sestamibi scan showed increased uptake at the lower pole of the right lobe of the thyroid. A right inferior parathyroidectomy was performed. Histopathology revealed chief cell type parathyroid adenoma. Last evaluated 4 months after surgery, the bone pains and proximal weakness had resolved, with significant improvement in the patient’s quality of life. Rickets in the setting of PHPT often masks the classical phenotype of PHPT. In a child with rickets, lack of improvement following vitamin-D supplementation, hypercalcemia at presentation or following vitamin-D supplementation are warning signs which necessitate further evaluation to rule out PHPT.Conflict of interest:None declared.  相似文献   
79.
Objective. Diarrhoeal relapses in patients with ulcerative colitis (UC) may be associated with enteric infections and its diagnosis may lessen avoidable exposure to corticosteroids and/or immunosuppressants. The purpose of this study was to assess the frequency of stool pathogens (parasitic and viral) in patients with active UC. Material and methods. This prospective cross-sectional study included 49 consecutive patients (32 M, 17 F, mean age 35.8±12 years) with active UC. Three stool samples were collected from each patient and examined for parasitic infection. Rectal biopsies were obtained during sigmoidoscopy to demonstrate cytomegalovirus (CMV) inclusion bodies and to conduct qualitative polymerase chain reaction (PCR) for CMV and herpes simplex virus (HSV) DNA detection. Results. Median duration of illness was 3.9±3.7 years and 83.7% of the patients had moderate to severe disease. The prevalence of parasitic infections in UC was 12%. The organisms isolated were Strongyloides stercoralis in 4%, Ankylostoma duodenale in 4%, Cryptosporidium in 2% and Entamoeba histolytica in 2% of the patients. The prevalence of CMV and HSV in rectal biopsies using qualitative PCR was 8% and 10%, respectively. No predictive factor was identified with CMV superinfection in patients with active UC. Conclusions. In India there is a high prevalence of parasitic and viral infections in patients with active UC. The results of the study suggest that, in tropical countries with a known high prevalence of parasitic diseases, aggressive evaluation for parasitic and viral infections should be carried out, as early identification and prompt treatment of such infections can improve the clinical course of patients with active UC.  相似文献   
80.
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