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91.
尿是人类和脊椎动物为了新陈代谢的需要,经由泌尿系统及尿路排出体外的液体排泄物。近年来,骆驼尿液因具有广泛的医疗作用而引起广泛关注。在中东地区,其主要用于对疾病的辅助治疗,包括发烧、感冒甚至癌症。研究表明,骆驼尿液中含有一些独特的生物化学成分,如刀豆氨酸可在不同肿瘤中表现出细胞毒性和抗肿瘤活性。且研究证实骆驼尿液具有抗菌、保肝、抗肿瘤和抗血小板活性等重要作用,极具研究价值。文章主要介绍了骆驼尿液中的有效生物化学成分,并对骆驼尿液在各种疾病中的医药作用进行详细阐述,为今后对骆驼尿液的进一步研究提供理论依据。  相似文献   
92.
Melatonin (MT) influences lipid metabolism in animals; however, the mechanistic effect of melatonin on liver fat and abdominal adipose deposition requires further clarity. In order to study the effects of melatonin on lipid metabolism, and hepatic fat and abdominal adipose deposition in animals, twenty Sprague–Dawley (SD) rats of 6 weeks of age with similar bodyweight were randomly divided into two groups: control (CTL) and MT-treated (10 mg/kg/day). During a 60-day experiment, food intake and bodyweight were measured daily and weekly respectively. At the end of treatment, blood samples were collected to collect plasma to quantify hormones and metabolic indicators of lipid metabolism. In addition, organ and abdominal adipose depots including liver, and omental, perirenal, and epididymal fat were weighed. Liver tissue was sampled for sectioning, long-chain fatty acid (LCFA) quantification, and gene chip and Real-time quantitative PCR (qPCR) analyses. The results showed that liver weight and index (ratio of liver weight to body weight) in MT group reduced by 20.69% and 9.63% respectively; omentum weight and index reduced by 59.88% and 54.93% respectively, and epididymal fat weight reduced by 45.34% (p = 0.049), relative to CTL. Plasma lipid indices, triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) with MT treatment decreased significantly compared with the control. Fat and 8 LCFA content in liver in MT group also decreased. Gene chip and qPCR demonstrated that there were 289 genes up-regulated and 293 genes down-regulated by MT. Further analysis found that the mRNA expression of lipolysis-related genes increased, while the mRNA expression of lipogenesis-related enzymes decreased (p < 0.05) with MT. This study concluded that melatonin greatly affected fat deposition, and hepatic LCFA supply and the expression of genes associated with lipogenesis and lipolysis.  相似文献   
93.
为更好地完善我国兽药质量监督抽检计划,通过对欧盟药品抽检管理工作机制的研究,本文分析了欧盟和我国兽药监督抽检管理方式的不同,从抽检责任部门、抽检目的、抽检计划内容、抽检计划制定流程、抽检品种的遴选和检测参数的确定等6方面进行了对比分析,探讨我国兽药质量监督抽检工作的管理中可以借鉴的方面。  相似文献   
94.
与男生相比,女大学生的人际交往有其自身的特点,主要表现在交往动机理想化、交往圈子生活化和交往行为技巧化三个方面。这三个特点决定了女大学生的人际关系状况对其心理上的影响要比男生更为强烈。  相似文献   
95.
AIMS: To determine factors that may influence the efficacy of an oral pelleted vaccine containing Mycobacterium bovis bacille Calmette-Guérin (BCG) to induce protection of brushtail possums against tuberculosis. To determine the duration of protective immunity following oral administration of BCG.

METHODS: In Study 1, a group of possums (n=7) was immunised by feeding 10 pellets containing dead Pasteur BCG, followed 15 weeks later with a single pellet of live Pasteur BCG. At that time, four other groups of possums (n=7 per group) were given a single pellet of live Pasteur BCG orally, a single pellet of live Danish BCG orally, 10 pellets of live Pasteur BCG orally, or a subcutaneous injection of live Pasteur BCG. For the oral pelleted vaccines, BCG was formulated into a lipid matrix, and each pellet contained approximately 107 colony forming units (cfu) of BCG, while the vaccine injected subcutaneously contained 106 cfu of BCG. A sixth, non-vaccinated, group (n=7) served as a control. All possums were challenged by the aerosol route with a low dose of virulent M. bovis 7 weeks after vaccination, and killed 7–8 weeks after challenge. Protection against challenge with M. bovis was assessed from pathological and bacteriological findings.

In Study 2, lipid-formulated live Danish BCG was administered orally to three groups of possums (10–11 per group), and these possums were challenged with virulent M. bovis 8, 29 or 54 weeks later. The possums were killed 7 weeks after challenge, to assess protection in comparison to a non-vaccinated group.

RESULTS: The results from Study 1 showed that vaccine efficacy was not adversely affected by feeding dead BCG prior to live BCG. Feeding 10 vaccine pellets induced a level of protection similar to feeding a single pellet. Protection was similar when feeding possums a single pellet containing the Pasteur or Danish strains of BCG. All vaccinated groups had significantly reduced pathological changes or bacterial counts when compared to the non-vaccinated group. In Study 2, oral administration of Danish BCG induced protection against challenge with M. bovis, which persisted for at least 54 weeks after vaccination. Some protection was observed in possums challenged 54 weeks after vaccination, but this protection was significantly less than that observed in groups vaccinated 29 or 8 weeks prior to challenge. There was a strong relationship between the proportion of animals producing positive lymphocyte proliferation responses to M. bovis antigens and protection against challenge with M. bovis.

CONCLUSIONS: Factors considered potentially capable of interfering with vaccination, including feeding dead BCG to possums prior to feeding live BCG, feeding multiple doses of BCG at one time, and changing strains of BCG, were shown not to interfere with the acquisition of protective immune responses in possums. Protection against tuberculosis was undiminished up to 29 weeks after vaccination with BCG administered orally. It is concluded that vaccination of possums by feeding pellets containing BCG is a robust and efficient approach to enhance the resistance of these animals to tuberculosis.  相似文献   
96.
提出了基于数学模型的幼苗外观特征自动检测方法,检测项目包括生长状态、子叶参数和胚轴参数。首先经过图像预处理提取幼苗二值图,利用行像素统计图确定特征参数基准点位置。然后以标定胚轴最小矩形倾斜度和宽度判定弯曲状态;子叶跨度通过两子叶端点距离确定,子叶展开角通过两子叶底端平展位置拟合线夹角判定;胚轴弯曲度通过胚轴中心线上曲率最大的位置为分界点分别判断两段斜度而求得,胚轴长、轴径结合斜度补偿求得。与手工测量数据对比,轴长、轴径和子叶跨度的相关系数分别为0.935 1、0.899 9和0.903 4,相对误差分别小于7%、5%和7%,绝对误差分别小于4 mm、0.2 mm和6 mm。  相似文献   
97.
据有关部门资料,2000年时,全国县级以上种子公司有2700多家,委托代销公司约55000多家。《中华人民共和国种子法》(以下简称《种子法》)施行两年后,全国种子产业大分化、大联合的局面初显端倪。据有关资料,全国注册资金3000万元以上种子企业已超过60家,注册资金500万元以上的种子公司近万家,委托代销公司可能在10万家以上。  相似文献   
98.
残膜回收工艺和收膜机构   总被引:2,自引:0,他引:2  
介绍了田间残膜的特性及机械化收膜工艺、残膜同收机中常用收膜机构的种类及工作特性,为残膜回收机的研究设计及主要工作部件结构的优化组合提供参考。  相似文献   
99.
永磁电机转子的接触有限元分析   总被引:2,自引:0,他引:2  
李殿起  赵清  姜彤 《农机化研究》2004,(3):77-78,81
应用大型有限元分析软件ANSYS,对永磁电机转子中永磁体和转子铁心的接触非线性状态,进行了三维有限元分析,得出了永磁电机转子的应力分布情况。结果表明:该结构转子的机械强度和刚度可满足电机最高转速时的机械性能要求,可以保证电机的安全运行。此分析求解过程也为类似的接触有限元分析提供了参考。  相似文献   
100.
木雕制品是对木材经过艺术构思后进行雕刻加工的一种工艺制品,可以用来装饰居室、殿堂、建筑,给人带来美及艺术的享受。随着人们生活水平的提高,该制品的需求量越来越大,产业前景非常好。为此,介绍了一种新型仿形雕刻机的结构和工作原理,利用该装备可以实现对木雕制品及木制品的仿形加工。  相似文献   
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