全文获取类型
收费全文 | 281篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 2篇 |
妇产科学 | 12篇 |
基础医学 | 35篇 |
口腔科学 | 83篇 |
临床医学 | 15篇 |
内科学 | 36篇 |
皮肤病学 | 3篇 |
神经病学 | 3篇 |
特种医学 | 7篇 |
外科学 | 30篇 |
综合类 | 5篇 |
一般理论 | 2篇 |
预防医学 | 9篇 |
眼科学 | 1篇 |
药学 | 17篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 14篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 17篇 |
2013年 | 13篇 |
2012年 | 27篇 |
2011年 | 19篇 |
2010年 | 16篇 |
2009年 | 17篇 |
2008年 | 25篇 |
2007年 | 33篇 |
2006年 | 17篇 |
2005年 | 22篇 |
2004年 | 11篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1994年 | 1篇 |
排序方式: 共有293条查询结果,搜索用时 15 毫秒
1.
BackgroundEpidemiological studies on peptic ulcer disease (PUD) have shown a recent decrease in hospital admissions in Western countries.ObjectiveThis paper aimed to study the current status and risk factors of PUD in a Nigerian metropolis.MethodsA cross-sectional study of symptomatic patients at upper gastrointestinal (GI) endoscopy diagnosed with PUD from February 2014 to September 2019 at a referral endoscopy facility in Port Harcourt, Niger delta region of Nigeria. The variables studied included demographics, symptoms and duration, blood group, chronic non-steroidal anti-inflammatory (NSAID) use, smoking, endoscopic and histology findings. Statistical analysis was performed using SPSS version 20.ResultsA total of 434 upper GI endoscopies were performed during the study period with thirty-one diagnosis of PUD made. The mean age of gastric ulcer (GU) and duodenal ulcer (DU) cases were 54.4 ± 20.2yrs and 48.1 ± 14.5yrs respectively (p = 0.367). GU to DU ratio was 1.4:1. H. pylori infection, chronic NSAID use and blood group O were seen in 7(22.5%), 8(25.8%) and 18(72.0%) respectively. Major indication in 21(67.7%) cases was gastrointestinal bleeding.ConclusionThere is a low diagnostic rate of PUD (6.7%) with pre-pyloric antral gastric ulcers as most common type and multifactorial aetiology. 相似文献
2.
C. Knipfer F. Wagner K. Knipfer G. Millesi J. Acero J.A. Hueto E. Nkenke 《International journal of oral and maxillofacial surgery》2019,48(6):841-846
The aim of this study was to evaluate learners’ acceptance of a webinar for continuing medical education that was instigated by the International Association of Oral and Maxillofacial Surgeons (IAOMS). A live, interactive webinar on orthognathic surgery was broadcast via the Internet. The learners’ acceptance of the webinar was evaluated using a standardized, validated questionnaire (Student Evaluation of Educational Quality, SEEQ). One hundred and fifty-three participants attended the webinar; 55 participants (46 male, nine female) completed the questionnaire. The mean age of the respondents was 41.6 ± 10.0 years. The age of male and female respondents did not differ significantly. The respondents were spread over five continents, with the highest number from Brazil. The SEEQ showed a high level of acceptance for almost all subscales. There was no statistically significant difference between male and female respondents concerning acceptance of the webinar (P = 0.614). The wide distribution of participants shows the potential for webinars as facilitators of barrier-free distribution of knowledge. The webinar was well accepted by the attendees independent of sex, specialty, and work experience. However, the sex ratio reflects the underrepresentation of women in oral and maxillofacial surgery. 相似文献
3.
Jin Y Kim HP Ifedigbo E Lau LF Choi AM 《American journal of respiratory cell and molecular biology》2005,33(3):297-302
We have used gene expression profiling approaches to identify new molecular targets in various models of lung injury and human lung diseases. Among the many genes that are significantly induced in these studies, cysteine-rich61 (Cyr61) consistently ranks as one of the most significant genes. Here, we use the well-established model of hyperoxia to better understand the function of Cyr61 in acute lung injury. Cyr61, a stress-related immediate-early response gene, has known diverse functions involving angiogenesis, tumorigenesis, and wound repair. It belongs to the newly discovered "CCN" family containing six growth and regulatory factors. We showed that hyperoxia induces Cyr61 expression in a variety of pulmonary cells and in lung tissue in vivo. Loss of function studies, by suppressing Cyr61 expression by siRNA, accelerated lung epithelial cell death after hyperoxia. Gain of function studies, by overexpressing Cyr61, significantly conferred increased resistance to hyperoxia-induced cell death. Moreover, cells overexpressing Cyr61 induce Akt activation. Inhibition of Akt by siRNA abrogated the protective effects of Cyr61-overexpressing cells in response to hyperoxia. Taken together, our data demonstrate that Cyr61 expression provides cytoprotection in hyperoxia-induced pulmonary epithelial cell death and that this effect was in part mediated via the Akt signaling pathway. 相似文献
4.
Head and neck tumors: imaging recurrent tumor and post-therapeutic changes with CT and MRI 总被引:5,自引:0,他引:5
Lell M Baum U Greess H Nömayr A Nkenke E Koester M Lenz M Bautz W 《European journal of radiology》2000,33(3):239-247
OBJECTIVE: To evaluate criteria for detection of tumor recurrence and post-treatment changes in patients with head and neck malignancies in computed tomography (CT) and magnetic resonance imaging (MRI). METHODS AND MATERIALS: Thirty-nine patients with head and neck carcinoma receiving radiochemotherapy were examined before, during and after therapy with MRI. Changes in signal intensity were correlated to histology or clinical course. Three hundred and thirty-one patients with head and neck malignancies were examined with CT after therapy. CT diagnoses were correlated with histology or clinical course. RESULTS: Main criteria for recurrent/residual tumor in MRI was infiltrative mass with high signal intensity in T2-weighted images and enhancement after Gd-DTPA in T1-weighted images. Radiation-induced changes led to false positive diagnosis in 46% in the interval up to 3 months after therapy and in 58% in the interval 3-6 months after therapy. The combination of a circumscribed, infiltrative mass with contrast enhancement in CT had a sensitivity of 86% and a specificity of 80%. CONCLUSION: CT could accurately demonstrate postoperative changes and tumor recurrence. MRI had advantages in differentiation of tumor and scar, but edema after radiation therapy can spoil diagnosis. 相似文献
5.
6.
Young Sexual Minority Males in the United States: Sociodemographic Characteristics And Sexual Attraction,Identity and Behavior 下载免费PDF全文
7.
Emeka W. Dumbili 《Drugs (Abingdon, England)》2014,21(6):434-439
Alcohol availability, use and misuse and their related problems are rising in many parts of the African continent, and this has been attributed to many factors such as non-existent or ineffective regulatory measures. In contemporary Nigeria, while a culture of intoxication is growing, there are no regulatory measures in the form of alcohol policies to reduce it. What exists is brewer-sponsored self-regulation. This article therefore critically analyses this self-imposed “drink responsibly” warning message, arguing that since responsible drinking messages are strategically designed to serve the interest of alcohol industries, it cannot be effective. The article further argues that since there are no definitions of standard drinks and where alcohol by volume (ABV) is scarcely inscribed on product labels of alcoholic beverages, such message will remain ineffective. Therefore, it recommends that an urgent step should be taken by the government to formulate and implement comprehensive evidence-based alcohol policies in Nigeria. 相似文献
8.
Celestine Chidi Ogbonna Geme Urge Dori Emeka Innocent Nweze Gilbert Muoneke Innocent Ejike Nwankwo Nkiru Akputa 《Asian Pacific journal of tropical medicine》2012,5(10):796-802
ObjectiveTo determine the prevalence, sex-age related intensity of urinary schistosomiasis and to compare such parameters among rural school children and rural farmers in selected communities in Obollo-Eke located in Southeast, Nigeria.MethodsA cross-sectional survey involving 1 337 school children and farmers was conducted in Obollo-Eke community between September 2006 and July 2007. Demographic data of subjects was collected using a questionnaire prepared for this purpose. Urine samples were collected and examined for haematuria and ova of Schistosoma haematobium (S. haematobium) using Medi-test Combi 9 and sedimentation technique respectively.ResultsThe prevalence of urinary schistosomiasis based on microscopic examination of the urine sediment for the ova of S. haematobium was 17.5% while the prevalence of haematuria was 15.6%. Infection intensity varied from light to heavy. In general, the prevalence was higher among males (20.8%) than females (14.6%; P>0.05) and was slightly higher among primary school children (18.0%; n=762) than farmers (16.9%; n=575; P>0.05). The age-specific prevalence of schistosomiasis among the study subjects ranged from 8.3% to 21.2% in 0-5 years and 11-15 years age groups respectively.ConclusionsHaematuria and mean egg/10 mL urine (r = 0.95; P<0.01) showed that both procedures are reliable for the diagnosis of the disease and can be used to ascertain the prevalence of the disease in any community. The comparative analysis of urinary bilharziasis among primary school children and rural farmers demonstrated that the infection is moderately high in these two risk population groups at Obollo-Eke. A robust intervention strategy is clearly needed. 相似文献
9.
BackgroundStress is an extremely adaptive phenomenon in human beings and cortisol is a known stress hormone. Examination has been described as a naturalistic stressor capable of affecting human health.ObjectivesTo estimate the relationship between serum cortisol, adrenaline, fasting blood glucose (FBG) and lipid profile during examination stress.MethodsTwo hundred and eight (208) apparently-healthy undergraduate students (aged, 24 ± 6 years) were involved in the study. Exactly 5 mls of venous blood was collected from each subject 1–3 hours before a major examination. A second assessment was done on the same students 3–4 weeks before any examination (control samples). Cortisol and adrenaline were assayed using ELISA techniques, FBG was assayed using enzymatic method while lipid parameters were assayed using standard enzymatic-spectrophotometric methods.ResultsThere was statistically significant increase in serum cortisol, adrenaline, Total cholesterol, HDL-cholesterol and LDL-cholesterol levels in students under examination stress compared to the non examination period (p=0.001, 0.013, 0.0001, 0.0001 and 0.0001, respectively). FBG showed no significant increase. There was also significant positive correlation (r=0.297, p=0.032) between serum cortisol and TC/HDL ratio (cardiac risk factor) before examination stress but not during the stress period.ConclusionsSignificant positive correlation was observed between cortisol and TC/HDL ratio before examination stress. 相似文献
10.