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   53篇
  免费   0篇
基础医学   7篇
临床医学   11篇
内科学   13篇
神经病学   2篇
特种医学   2篇
外科学   2篇
综合类   1篇
预防医学   6篇
眼科学   1篇
药学   7篇
中国医学   1篇
  2023年   3篇
  2021年   3篇
  2020年   1篇
  2019年   3篇
  2017年   4篇
  2014年   3篇
  2013年   5篇
  2012年   8篇
  2011年   5篇
  2010年   1篇
  2009年   2篇
  2008年   1篇
  2007年   2篇
  2006年   3篇
  2005年   3篇
  2004年   2篇
  2003年   1篇
  2002年   1篇
  1998年   1篇
  1996年   1篇
排序方式: 共有53条查询结果,搜索用时 156 毫秒
31.
A study was undertaken to evaluate an alternative source of arsenicosis in human food chain through livestock. Thirty milch cattle and 20 poultry birds along with their eggs were selected randomly from two endemic villages of Nadia district and one nonendemic villages of Hooghly district in West Bengal, India. Milk, feces, urine, and hair samples of cattle and feed materials, such as water and straw, were collected to analyze arsenic status. Arsenic concentration in egg yolk and albumen from poultry eggs and different poultry organs after culling was estimated. Distribution of arsenic in animal body indicates that major portion of arsenic was eliminated through feces, urine, and milk. Poultry egg yolk, albumen, and poultry products retain arsenic in all organs. Cows and poultry birds reared in endemic zone retain significantly higher concentration of arsenic. Consumption of egg, agricultural produces grown in contaminated soil, and milk might have produced arsenicosis and may be considered as alternative source of arsenic contamination.  相似文献   
32.
Severity of arsenic toxicity was reported to vary depending on its species. The present study reflects the status of different species of arsenic in goat following long-term exposure of arsenic leading to hepatic damage. The experiment was conducted with six black Bengal goats, which were administered with sodium arsenite orally at a dose rate of 2 mg kg−1 daily for 84 days. Faeces, urine, hair and blood samples were collected from those animals at 14 days interval. Excretion of total arsenic was reduced from 56 days onwards through both faeces and urine indicating higher accumulation of arsenic in body. The speciation study revealed that urinary arsenic was mainly of organic type, whereas hair accumulated almost equal proportion of arsenite, arsenate and organo arsenicals. Goats excreted high proportion of organo arsenicals through faeces possibly due to hepatobiliary secretion of organo arsenic into the gut. Significantly elevated serum alanine aminotransferase and aspartate aminotransferase activities (p < 0.05) alongwith histopathological changes in liver indicated hepatotoxicity. The arsenite fraction increased and organic proportion decreased in urine as the time progressed, which indicates that arsenite gets methylated in liver of goat. The study thus alluded that the toxicity of arsenic would aggravate if the animals were exposed for long time as the hepatotoxicity progressed resulting in decreased methylation and formation of organo arsenicals and decreased excretions through urine.  相似文献   
33.
We determine whether age is a prognostic factor for surgical outcomes of external dacryocystorhinostomy (Ex-DCR). This retrospective cohort study conducted at Tilganga Institute of Ophthalmology (Kathmandu, Nepal) compared pediatric Ex-DCR procedures (age ≤ 15 years) to adult Ex-DCR procedures (age > 15 years) and was performed between January 2013 and December 2013, with a minimum follow-up period of 6 months. Primary outcome measure was rate of success, defined as complete resolution of subjective symptom(s) of epiphora (subjective success), combined with patent lacrimal passage on syringing (anatomical success) at last follow-up visit. Other outcome measures included clinical presentation, diagnosis, intraoperative complications and post-operative complications. In total, 154 Ex-DCR procedures were included, with an age range of 8 months to 81 years (mean age 36.4 ± 21.0 years). In all, 38 pediatric Ex-DCR procedures were compared to 116 adult procedures. Success rates were 97% in the pediatric group and 95% in the adult group, with no clinically or statistically significant difference in success rate or complication rate between groups (p > 0.05). Our study yielded high success rates of Ex-DCR in both pediatric and adult age groups suggesting that Ex-DCR remains an optimal treatment choice for all age groups. With no difference in surgical outcomes between pediatric and adult patients, including complication rate, we conclude that age is not a prognostic factor for Ex-DCR failure. We do not recommend adjuvant therapy for pediatric patients.  相似文献   
34.
Oxidative stress basically defines a condition in which prooxidant–antioxidant balance in the cell is disturbed; cellular biomolecules undergo severe oxidative damage, ultimately compromising cells viability. In recent years, a number of studies have shown that oxidative stress could cause cellular apoptosis via both the mitochondria-dependent and mitochondria-independent pathways. Since these pathways are directly related to the survival or death of various cell types in normal as well as pathophysiological situations, a clear picture of these pathways for various active molecules in their biological functions would help designing novel therapeutic strategy. This review highlights the basic mechanisms of ROS production and their sites of formation; detail mechanism of both mitochondria-dependent and mitochondria-independent pathways of apoptosis as well as their regulation by ROS. Emphasis has been given on the redox-sensitive ASK1 signalosome and its downstream JNK pathway. This review also describes the involvement of oxidative stress under various environmental toxin- and drug-induced organ pathophysiology and diabetes-mediated apoptosis. We believe that this review would provide useful information about the most recent progress in understanding the mechanism of oxidative stress–mediated regulation of apoptotic pathways. It will also help to figure out the complex cross-talks between these pathways and their modulations by oxidative stress. The literature will also shed a light on the blind alleys of this field to be explored. Finally, readers would know about the ROS-regulated and apoptosis-mediated organ pathophysiology which might help to find their probable remedies in future.  相似文献   
35.
过敏性鼻炎是发生在鼻黏膜的变态反应性疾病,随着工业的发展、环境的污染以及生活压力的增加,过敏性鼻炎的发病逐渐增多。医务工作者一直致力于过敏性鼻炎的防治,不断探索新的药物和治疗方法以期达到更有效的治疗效果。笔者从过敏性鼻炎的病因、诊断以及治疗对其进行阐述,以便能更好地治疗过敏性鼻炎。  相似文献   
36.
11条新西兰兔进行血管腔内超声(IVUS)研究。其中8条经高胆固醇饲养6个月;另3条予正常饮食对照。采用6.2F,频率20MHz腔内超声导管。由腹主动脉下端水平插入超声导管至升主动脉,然后逐步退出,观察主动脉内膜、中膜和外膜的形态特征。结果发现,正常兔主动脉在腔内超声观察下均无内、中和外膜三层结构之分。39个切面管壁弥漫性增厚,其形态看似管壁的三层结构,病理证实34个切面有脂质斑块。平滑肌增生的脂质斑块,回声影低于血管壁。部份脂质斑块存在弥漫性纤维化、胆固醇结晶和少量镜下可见的钙化灶,回声影致密,与血管壁的回声相同,但其后无声影。腔内超声测定的斑块面积和厚度与病理结果比较,差别无显著意义(P>0.05),两者高度相关(分别为r=0.97,P<0.0005和r=0.96,P<0.0005)。  相似文献   
37.
ObjectiveThe aim of this study was to compare cardiovascular autonomic function tests (AFT) and vibration perception threshold (VPT) of patients with type 2 diabetes mellitus (T2DM) with controls.Research Design/MethodsThe study was conducted on 60 diabetic patients comparing with 30 controls. The cardiovascular AFT and VPT were assessed in both groups.ResultsAmong cardiovascular AFT, E:I ratio [1.24 (1.2–1.32) vs 1.3 (1.24–1.4), p = 0.001], and Valsalva ratio [1.28 (1.22–1.4) vs 1.6 (1.5–1.73), p = 0.001], the indicators of parasympathetic reactivity were reduced in T2DM. Rise in DBP during handgrip, an indicator of sympathetic reactivity was lower in T2DM [12 (10–14) vs 16 (14–18) mmHg, p = 0.001] whereas, fall in SBP during head up tilt [4 (4–8) vs 5 (4–8) mmHg] was comparable. VPT (somatic sensation) was comparable between T2DM and control.ConclusionAutonomic involvement is more marked than somatic, and parasympathetic involvement is more marked than the sympathetic, possibly reflecting severity and chronological pattern of their involvement.  相似文献   
38.
Oxorhenium(V) complexes of two thioether amines have been synthesized and characterized spectroscopically. The five-coordinated ReO(3+) moiety is satisfied by the amine compounds behaving as dibasic tetradentate (NSSN) ligands and a chloride ion. The radioanalytical studies of their technetium analogs have been carried out at different pH values in the range 3-10. The solvent extraction, TLC, electrophoresis and HPLC studies using (99m)Tc radiotracer indicate that the labeled complex with the TcO(3+) core is similar to the rhenium complex with the ReO(3+) core.  相似文献   
39.
Named entity recognition is an extremely important and fundamental task of biomedical text mining. Biomedical named entities include mentions of proteins, genes, DNA, RNA, etc which often have complex structures, but it is challenging to identify and classify such entities. Machine learning methods like CRF, MEMM and SVM have been widely used for learning to recognize such entities from an annotated corpus. The identification of appropriate feature templates and the selection of the important feature values play a very important role in the success of these methods. In this paper, we provide a study on word clustering and selection based feature reduction approaches for named entity recognition using a maximum entropy classifier. The identification and selection of features are largely done automatically without using domain knowledge. The performance of the system is found to be superior to existing systems which do not use domain knowledge.  相似文献   
40.
Spontaneous coronary artery dissection (SCAD) should be considered as a cause of the acute coronary syndrome in young patients with few apparent risk factors for coronary artery disease, in females in the peripartum period, and in patients who are at a higher risk for this condition. SCAD can also present as sudden death and cardiogenic shock. Several mechanisms have been described in the pathophysiology of this condition. Urgent coronary angiography is indicated if SCAD is suspected. Percutaneous coronary artery stenting and coronary artery bypass grafting are the main treatment strategies.  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