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   1217篇
  免费   54篇
  国内免费   2篇
耳鼻咽喉   29篇
儿科学   130篇
妇产科学   48篇
基础医学   114篇
口腔科学   71篇
临床医学   95篇
内科学   216篇
皮肤病学   123篇
神经病学   80篇
特种医学   47篇
外科学   145篇
综合类   9篇
预防医学   29篇
眼科学   22篇
药学   54篇
中国医学   2篇
肿瘤学   59篇
  2024年   2篇
  2023年   10篇
  2022年   10篇
  2021年   34篇
  2020年   24篇
  2019年   30篇
  2018年   40篇
  2017年   30篇
  2016年   39篇
  2015年   36篇
  2014年   49篇
  2013年   82篇
  2012年   90篇
  2011年   77篇
  2010年   51篇
  2009年   48篇
  2008年   87篇
  2007年   106篇
  2006年   102篇
  2005年   72篇
  2004年   82篇
  2003年   67篇
  2002年   53篇
  2001年   8篇
  2000年   7篇
  1999年   10篇
  1998年   9篇
  1997年   1篇
  1996年   1篇
  1994年   2篇
  1993年   3篇
  1992年   4篇
  1991年   2篇
  1990年   1篇
  1988年   1篇
  1984年   1篇
  1981年   1篇
  1974年   1篇
排序方式: 共有1273条查询结果,搜索用时 15 毫秒
1.
2.
BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder characterised by platelet aggregation causing microvascular occlusion. Early diagnosis and utilization of plasmapheresis can provide an improvement in prognosis. CASE REPORT: A 17 year old male with classical findings of TTP was later diagnosed as systemic lupus erythematosus (SLE). Plasmapheresis resulted in the significant amelioration of the course. CONCLUSION: The coexistence of TTP and SLE may facilitate a better understanding of in the pathophysiology of TTP. These association may provide the role of autoimmunity in TTP. SLE should be considered in the differential diagnosis of patients with TTP because of therapeutic implications.  相似文献   
3.
Oral implications of osteoporosis.   总被引:5,自引:0,他引:5  
OBJECTIVES: The association between osteoporosis and oral health remains a matter of controversy. It is important to confirm whether there is a role of osteoporosis in bone loss in the jaws, periodontal diseases, tooth loss, and other oral tissue changes. The objective of this article is to review and summarize the published literature on the associations between osteoporosis and various oral conditions such as bone loss in the jaws, periodontal diseases, and tooth loss. METHODS: A search of the computerized database MEDLINE was conducted. Clinical information concerning systemic osteoporosis and animal studies reporting possible associations between osteoporosis and changes in the dental and oral tissues were included. The review focus was on studies involving (1) methods for assessing bone mineral density (BMD); (2) methods for assessing osteoporosis-related changes in intraoral sites; (3) associations between mandibular BMD and skeletal BMD; (4) changes in the jaws, periodontal tissues, and temporomandibular joint concurrent with osteoporosis; (5) changes in the oral tissues following estrogen deficiency; and (6) effects of estrogen-hormone replacement therapy and/or calcium and vitamin D on oral health. RESULTS: Ninety-seven studies conducted in various parts of the world were identified. Evidence from prospective studies supports the contention that individuals with osteoporosis may be at increased risk for the manifestations of oral osteoporosis; however, such risk is not definitively proven. Studies suggest that findings on dental panoramic radiographs may be used to detect individuals with low BMD. CONCLUSIONS: Further well-controlled studies are needed to better elucidate the inter-relationship between systemic and oral bone loss and to clarify whether dentists could usefully provide early warning for osteoporosis risk.  相似文献   
4.
Goldenhar's Syndrome (oculo-auriculo-vertebral dysplasia) is a wide spectrum of congenital anomalies that involves structures arising from the first and second branchial arches. In this report, a case of a male infant, with the features of hemi facial microsomia, anotia, vertebral anomalies, congenital facial nerve palsy and lagophthalmos is described. Although the syndrome itself is not uncommon, the presence of congenital facial nerve palsy, which has been reported in rare cases, prompted this case report.  相似文献   
5.
BACKGROUND AND PURPOSE: The evaluation of adenosine deaminase (ADA) activity in sera of patients with hepatitis should be considered a useful tool in the monitoring of their clinical status. In this study, we aimed to determine the relationship between viral load, transaminase levels, and serum ADA levels in hepatitis B virus (HBV)- and hepatitis C virus (HCV)-infected patients. METHODS: Seventy three patients with hepatitis B, 71 patients with hepatitis C and 40 healthy individuals were included. Patients with HBV and HCV infections were classified into 3 groups according to viral load. Serum ADA levels were investigated by colorimetric assays. RESULTS: Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and ADA levels of HBV- and HCV-infected patients were higher than those of the control group. These differences were statistically significant for the levels of all enzymes in HCV-infected patients (p<0.05), and all except AST (p>0.05) in HBV-infected patients. ADA levels of HBV-infected patients with high viral loads were higher than those in HBV-infected patients with intermediate and low viral loads, and the difference was detectably significant between patients with high and intermediate viral loads. Evaluation of HCV-infected patients according to viral load showed no statistically significant relationship between viral load and serum ADA, ALT, and AST levels (p>0.05). HBV- and HCV-infected patients with high ALT and AST levels showed statistically significantly higher levels of ADA than patients with normal ALT and AST levels (p<0.001). CONCLUSIONS: We suggest that serum ADA levels are associated more with the level of serum transaminases than viral load in HBV- and HCV-infected patients. In the treatment of patients with hepatitis, serum ADA levels should be considered a useful tool for the monitoring of liver condition.  相似文献   
6.
To examine the influence of diabetes education on well-being, 255 patients with type 2 diabetes were recruited according to whether they attended a diabetes education program (n=126) or not (n=129). In patients who had participated in the program, the mean anxiety score was significantly lower, whereas positive well-being and general well-being scores were significantly higher than for patients who had not participated. Factors related to lower well-being included: being female, taking insulin, not attending a diabetes education program and having HbA(1c) level greater than 8%. The odds of having better well-being were two-fold higher in patients participating the diabetes education program compared with those who had not. Diabetes education has a crucial role in improving the well-being of patients with type 2 diabetes. All patients with diabetes should be encouraged to attend a diabetes education program.  相似文献   
7.
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.  相似文献   
8.
Objective: Various foods play important role in the pathogenesis of gastroesophageal reflux disease (GERD). These foods are shown to increase gastroesophageal reflux symptoms via various mechanisms and majority of these foods also contain nickel. The purpose of this study is to evaluate the relationship between Nickel sensitivity and GERD.

Material and methods: Fifty-four patients diagnosed with GERD and 50 healthy volunteers who were admitted to our gastroenterology outpatient clinic were took part in the study. European standard patch test series, nickel-containing test units and corticosteroids were applied to the patient body; upper back. Evaluation was performed according to the scheme of the International Contact Dermatitis Research Group (ICDRG). The positive and negative reactions were recorded at the hours of 48, 72 and 96. Following the test implementations, 7?days later, the tests were reevaluated for late reactions. Statistics package for Social Sciences (SPSS) 17 package program was used for statistical evaluation and results of tests were compared between groups with the Chi-squared test. p?Results: Individuals in both groups were statistically similar in terms of age and gender. Nickel sensitivity was found to be positive in 48.2 and %22 of the GERD patients and control group, respectively. Difference between groups was statistically significant (p?=?0.008).

Conclusions: Nickel sensitivity was significantly higher in GERD patients compared to the control group. In addition to imbalance between defensive and aggressive forces of the esophagus, there seems to be an association between nickel sensitivity and GERD.  相似文献   
9.
Here, we developed the lysozyme imprinted bacterial cellulose (Lyz-MIP/BC) nanofibers via the surface imprinting strategy that was designed to recognize lysozyme. This study includes the molecular imprinting method onto the surface of bacterial cellulose nanofibers in the presence of lysozyme by metal ion coordination, as well as further characterizations methods FTIR, SEM and contact angle measurements. The maximum lysozyme adsorption capacity of Lyz-MIP/BC nanofibers was found to be 71 mg/g. The Lyz-MIP/BC nanofibers showed high selectivity for lysozyme towards bovine serum albumin and cytochrome c. Overall, the Lyz-MIP/BC nanofibers hold great potential for lysozyme recognition due to the high binding capacity, significant selectivity and excellent reusability.  相似文献   
10.
Cisplatin is a widely used antineoplastic agent in the treatment of various cancers. Peripheral neuropathy is a well‐known side effect of cisplatin and has potential to result in limiting and/or reducing the dose, decreasing the quality of life. Thus, effective treatments are needed. Agmatine is an endogenous neuromodulator that has been shown to exert antiallodynic effects in various animal studies. The first aim of this study was to investigate the in vitro effects of agmatine on cisplatin‐induced neurotoxicity. Primary cultures of dorsal root ganglia (DRG) which are the primary target of drug injury were prepared. DRG cells were incubated with cisplatin (100, 200, 500 μm ). Then, agmatine (10, 100, 500 μm ) was administered with the submaximal concentration of cisplatin. Cisplatin caused concentration‐dependent neurotoxicity, and agmatine did not alter this effect. The second aim was to investigate the effects of agmatine on cisplatin‐induced peripheral neuropathy in rats and the influence of nitric oxide synthase (NOS) inhibitor, L‐NAME, in this effect. Female Sprague Dawley rats received intraperitoneal saline (control), cisplatin (3 mg/kg), cisplatin+agmatine (100 mg/kg), or cisplatin+agmatine+L‐NAME (10 mg/kg) once a week for 5 weeks. The mechanical allodynia, hot plate, and tail clip tests were performed, and DRG cells and sciatic nerves were analyzed. Agmatine and agmatine+L‐NAME combination attenuated CIS‐induced mechanical allodynia and degeneration in DRG cells and sciatic nerves. However, L‐NAME did not potentiate the antiallodynic or neuroprotective effect of agmatine. These findings indicate that agmatine co‐administration ameliorates cisplatin‐induced neuropathy and may be a therapeutic alternative.  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