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   118篇
  免费   6篇
  国内免费   3篇
耳鼻咽喉   1篇
儿科学   2篇
妇产科学   5篇
基础医学   21篇
临床医学   9篇
内科学   36篇
皮肤病学   4篇
神经病学   6篇
特种医学   2篇
外科学   7篇
预防医学   17篇
眼科学   1篇
药学   5篇
肿瘤学   11篇
  2023年   1篇
  2022年   2篇
  2021年   8篇
  2020年   2篇
  2019年   3篇
  2018年   5篇
  2017年   2篇
  2016年   3篇
  2015年   9篇
  2014年   6篇
  2013年   6篇
  2012年   9篇
  2011年   12篇
  2010年   9篇
  2009年   5篇
  2008年   4篇
  2007年   9篇
  2006年   9篇
  2005年   10篇
  2004年   4篇
  2003年   3篇
  2002年   2篇
  1999年   1篇
  1998年   1篇
  1995年   1篇
  1994年   1篇
排序方式: 共有127条查询结果,搜索用时 31 毫秒
71.
Alcoholic liver disease(ALD) is a major cause of acute and chronic liver injury. Extensive evidence has been accumulated on the pathological process of ALD during the past decades. However, effective treatment options for ALD are very limited due to the lack of suitable in vivo models that recapitulate the full spectrum of ALD. Experimental animal models of ALD, particularly rodents, have been used extensively to mimic human ALD. An ideal animal model should recapitulate all aspects of the ALD process, including significant steatosis, hepatic neutrophil infiltration, and liver injury. A better strategy against ALD depends on clear diagnostic biomarkers, accurate predictor(s) of its progression and new therapeutic approaches to modulate stop or even reverse the disease. Numerous models employing rodent animals have been established in the last decades to investigate the effects of acute and chronic alcohol exposure on the initiation and progression of ALD. Although significant progress has been made in gaining better knowledge on the mechanisms and pathology of ALD, many features of ALD are unknown, and require further investigation, ideally with improved animal models that more effectively mimic human ALD. Although differences in the degree and stages of alcoholic liver injury inevitably exist between animal models and human ALD, the acquisition and translational relevance will be greatly enhanced with the development of new and improved animal models of ALD.  相似文献   
72.
Numerous studies have shown there is consistent evidence implicating genetic factors in the etiology of autism. In some cases chromosomal abnormalities have been identified. One type of these abnormalities is gaps and breaks nonrandomly located in chromosomes, denominated fragile sites (FS). We cytogenetically analyzed a group of autistic individuals and a normal population, and we examined the FS found in both samples with the aim of (1) comparing their FS expression, (2) ascertaining whether any FS could be associated with our autistic sample, and (3) examining if there are differences between individual and pooled-data analyses. Different statistical methods were used to analyse the FS of pooled and individual data. Our results show that there are statistically significant differences in the spontaneous expression of breakages between patients and controls, with a minimal sex difference. Using the method for pooled data, eight autosomal FS have preferential expression in patients and five patients were found to be positive at FS Xq27.3. With the method per-individual analysis, four FS emerged as specific in our autistic sample. Inferences of FS from pooled data were different from those of individual data. The findings suggest that although analysis of pooled data is necessitated by the problem of sparse data, analysis of single individuals is essential to know the significance of FS in autism.  相似文献   
73.
The aim of the present work was to study the potential involvement of hypothalamic galanin system in the anorectic mechanism of fluoxetine in obese Zucker rats. Male obese Zucker (fa/fa) rats were administered fluoxetine (10 mg/kg; i.p.) daily for two weeks. The control group was given 0.9% NaCl solution. Significant decreases in food intake, final body weight and total body fat were observed after fluoxetine treatment. Although fluoxetine-treated rats showed a decrease in urine elimination, this effect was not enough to compensate decreased water intake, leading to dehydration, as showed by decreased body water content. Chronic fluoxetine administration increased the numbers of galanin positively immunostained neural cells in medial and lateral preoptic areas, lateral hypothalamic area and paraventricular nucleus (rostral and magnocellular regions), without changes in dorsomedial, ventromedial, supraoptic, suprachiasmatic and arcuate nuclei. Taken into account that galanin stimulates appetite, these results could represent rather a compensatory response against reduced food intake than a direct anorectic mechanism. Changes in the magnocellular region of the hypothalamic paraventricular nucleus suggest a role for galanin neural circuits at this level in fluoxetine-induced hydro-osmotic impairment.  相似文献   
74.
Pneumocystis pneumonia in HIV-positive adults, Malawi   总被引:1,自引:0,他引:1  
In a prospective study of 660 HIV-positive Malawian adults, we diagnosed Pneumocystis jirovecii pneumonia (PcP) using clinical features, induced sputum for immunofluorescent staining, real-time PCR, and posttreatment follow-up. PcP incidence was highest in patients with the lowest CD4 counts, but PcP is uncommon compared with incidences of pulmonary tuberculosis and bacterial pneumonia.  相似文献   
75.
Collection of blood from the submandibular vein allows simple and rapid processing of many animals without anesthesia and facilitates rapid recovery with no signs of pain and discomfort in the mice. Here we compared the submandibular vein and retroorbital plexus blood collection methods, to determine the potential effect of the sampling technique on several clinical biochemistry parameters in C57BL/6J mice. We found statistically significant differences for 8 of the 9 biochemical parameters studied between the 2 blood sampling techniques. Compared with samples collected from the retroorbital plexus, blood obtained from the submadibular vein had higher levels of AST, ALT, protein, albumin, triglycerides, total cholesterol, and creatinine. Glucose values of retroorbital blood were higher than those from the submandibular vein. Urea levels were similar for both sampling techniques. Our results demonstrate that the technique used to obtain blood samples affects parameters commonly used to assess animal health. We recommend caution when comparing results of biochemical analysis of blood obtained from the submandibular vein in mice with reference values obtained by other blood sampling techniques.Blood for biochemical analysis can be obtained in mice by various techniques, including bleeding from the retroorbital plexus (also described as the retrobulbar venous plexus and periorbital sinus), by the tailclip technique, by cardiocentesis, and by saphenous venipuncture.7,9,10 Each method can affect the outcome of serum biochemistry analysis, due to differences in handling, restraining, anesthesia, invasiveness, and animal discomfort.1,13,19,20 The retroorbital blood-collection method is widely used in mice.8,9,13 Although this method consistently yields a reasonable blood volume when the investigator is experienced in the procedure, retroorbital blood collection is controversial because it may cause pain, distress, or even blindness when performed incorrectly.21,22 A joint working group on refinement does not recommend retroorbital sampling because of the risk of tissue damage12 and states that this method is acceptable only as a terminal procedure while the animal is anesthetized.17Recently, new blood sampling methods considered more humane and less aggressive than the retroorbital technique, such submandibular venipuncture, have been developed in mice.8 Although several reports16,19 address the retroorbital sampling method, detailed information regarding submandibular venipuncture is scarce in the published literature. The goal of our study was to compare the retroorbital technique of blood collection with submandibular venipuncture to determine the effect of this new bleeding method on several clinical biochemistry parameters in C57BL/6J mice.  相似文献   
76.
Background  In Gipuzkoa, screening for breast cancer was initiated in 1997 and in this paper we present breast cancer characteristics and survival for women diagnosed during the pre-screening period. Methods  All cases diagnosed during 1995–1996 were included and the tumour characteristics were analysed. One-, five- and ten-year observed and relative survival (RS) were estimated overall, as well as by age and tumour characteristics. Multiple regression models were used to evaluate the effect of tumour characteristics on ten-year RS. Results  Six hundred and twenty-two cases with a mean age of 60.7±15 years were included. The mean follow-up was 7.5 years (max. 10) with a mortality of 40.5%. Ductal carcinoma accounted for 78% of all cases; almost 50% had good or moderate differentiation and 28% were positive for both hormone receptors studied. Nearly 80% of cases were diagnosed in stage I or II and breast-conserving surgery was employed more often than mastectomy. Age-standardised RS was 77% (95% CI 72.1-82.3) and 68% (95% CI 60.4–74.6), five and ten years after diagnosis respectively. The relative excess risk of death was significantly different only for age, stage and degree of differentiation. Discussion  This study shows an increase in survival compared to previous studies in the region. This could be explained by advances in diagnosis and treatment, as demonstrated by younger age and earlier stage at diagnosis and by the therapy profiles. Age and stage were shown to be major predictors of survival in our study and adjustment for the other factors had only limited effects on the risk of death for these two variables.  相似文献   
77.
78.
79.
RATIONALE: Identification of risk factors for lung cancer can help in selecting patients who may benefit the most from smoking cessation interventions, early detection, or chemoprevention. OBJECTIVE: To evaluate whether the presence of emphysema on low-radiation-dose CT (LDCT) of the chest is an independent risk factor for lung cancer. METHODS: The study used data from a prospective cohort of 1,166 former and current smokers participating in a lung cancer screening study. All individuals underwent a baseline LDCT and spirometry followed by yearly repeat LDCT studies. The incidence density of lung cancer among patients with and without emphysema on LDCT was estimated. Stratified and multiple regression analyses were used to assess whether emphysema is an independent risk factor for lung cancer after adjusting for age, gender, smoking history, and the presence of airway obstruction on spirometry. RESULTS: On univariate analysis, the incidence density of lung cancer among individuals with and without emphysema on LDCT was 25.0 per 1,000 person-years and 7.5 per 1,000 person-years, respectively (risk ratio [RR], 3.33; 95% confidence interval [CI], 1.41 to 7.85). Emphysema was also associated with increased risk of lung cancer when the analysis was limited to individuals without airway obstruction on spirometry (RR, 4.33; 95% CI, 1.04 to 18.16). Multivariate analysis showed that the presence of emphysema (RR, 2.51; 95% CI, 1.01 to 6.23) on LDCT but not airway obstruction (RR, 2.10; 95% CI, 0.79 to 5.58) was associated with increased risk of lung cancer after adjusting for potential cofounders. CONCLUSIONS: Results suggest that the presence of emphysema on LDCT is an independent risk factor for lung cancer.  相似文献   
80.
A real-time polymerase chain reaction (PCR) assay targeting the internal transcribed spacer 2 region of the ribosomal RNA gene was developed for the detection of Isospora belli DNA in fecal samples, including an internal control to detect inhibition during the amplification process. The assay was performed on species-specific DNA controls (n = 27) and a range of positive (n = 21) and negative (n = 120) stool samples, and achieved 100% specificity and sensitivity. The simple fecal sample collection procedure, the high-throughput potential, and the possibility of quantification makes the I. belli real-time PCR assay a powerful diagnostic tool for epidemiologic studies with possibilities for extension to other helminthes and protozoa using additional molecular targets. In addition, this Isospora PCR could augment the clinical laboratory diagnosis of isosporiasis, in particular, in patients with a travel history to developing countries.  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