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1.
根据胜利黄岛原油的性质,在筛选了几十种破乳剂的基础上,选择了酚醛树脂和环氧环烷,环氧乙烷的嵌段共聚物作破乳剂,探讨了破乳剂组成对原油脱水,脱盐以及界面张力的影响,通过静态脱盐,脱水试验,得到了适合黄岛原油的最佳破乳剂组成。  相似文献   
2.
对1986年-1990年《江西医学院学报》的引文进行了数理统计与分析,定量描述其引文的类型,文种,时序以及在被引期刊中的分布。测定了该刊引用文献的半衰期与核心期刊,并对论著及著者分布作了分析。  相似文献   
3.
豚鼠中耳(听泡)内滴入0.5%、1%、2%环丙沙星与庆大霉素滴耳液7天或21天,借助光镜和扫描电镜观察内耳的显微和超微结构变化。结果证明环丙沙星对内耳没有明显的毒性作用。庆大霉素则使耳蜗明显受损,以底回为重,Corti’s器外毛细胞坏死较多,内毛细胞及支持细胞病变较轻。位觉斑耳石脱落,毛细胞纤毛粘连、脱落。壶腹嵴中央区纤毛也缺失。本实验对客观评价环丙沙星对内耳的作用及临床使用提供了形态学资料。  相似文献   
4.
As most mechanisms of adaptive immunity evolved during the divergence of vertebrates, the immune systems of extant vertebrates represent different successful variations on the themes initiated in their earliest common ancestors. The genes involved in elaborating these mechanisms have been subject to exceptional selective pressures in an arms race with highly adaptable pathogens, resulting in highly divergent sequences of orthologous genes and the gain and loss of members of gene families as different species find different solutions to the challenge of infection. Consequently, it has been difficult to transfer to the chicken detailed knowledge of the molecular mechanisms of the mammalian immune system and, thus, to enhance the already significant contribution of chickens toward understanding the evolution of immunity. The availability of the chicken genome sequence provides the opportunity to resolve outstanding questions concerning which molecular components of the immune system are shared between mammals and birds and which represent their unique evolutionary solutions. We have integrated genome data with existing knowledge to make a new comparative census of members of cytokine and chemokine gene families, distinguishing the core set of molecules likely to be common to all higher vertebrates from those particular to these 300 million-year-old lineages. Some differences can be explained by the different architectures of the mammalian and avian immune systems. Chickens lack lymph nodes and also the genes for the lymphotoxins and lymphotoxin receptors. The lack of functional eosinophils correlates with the absence of the eotaxin genes and our previously reported observation that interleukin- 5 (IL-5) is a pseudogene. To summarize, in the chicken genome, we can identify the genes for 23 ILs, 8 type I interferons (IFNs), IFN-gamma, 1 colony-stimulating factor (GM-CSF), 2 of the 3 known transforming growth factors (TGFs), 24 chemokines (1 XCL, 14 CCL, 8 CXCL, and 1 CX3CL), and 10 tumor necrosis factor superfamily (TNFSF) members. Receptor genes present in the genome suggest the likely presence of 2 other ILs, 1 other CSF, and 2 other TNFSF members.  相似文献   
5.
The status of training in clinical genetics and genetic counseling in Asia is at diverse stages of development and maturity. Most of the training programs are in academic training centers where exposure to patients in the clinics or in the hospital is a major component. This setting provides trainees with knowledge and skills to be competent geneticists and genetic counselors in a variety of patient care interactions. Majority of the training programs combine clinical and research training which provide trainees a broad and integrated approach in the diagnosis and management of patients while providing opportunities for research discoveries that can be translated to better patient care. The background on how the training programs in clinical genetics and genetic counseling in Asia evolved to their current status are described. Each of these countries can learn from each other through sharing of best practices and resources.  相似文献   
6.
Sim AC  Luhur A  Tan TM  Chow VT  Poh CL 《Virology》2005,341(1):72-79
Enterovirus 71 (EV71) is a highly infectious major causative agent of hand, foot, and mouth disease (HFMD) which could lead to severe neurological complications. There is currently no effective therapy against EV71. In this study, RNA interference (RNAi) is employed as a therapeutic approach for specific viral inhibition. Various regions of the EV71 genome were targeted for inhibition by chemically synthesized siRNAs. Transfection of rhabdomyosarcoma (RD) cells with siRNA targeting the 3'UTR, 2C, 3C, or 3D region significantly alleviated cytopathic effects of EV71. The inhibitory effect was dosage-dependent with a corresponding decrease in viral RNA, viral proteins, and plaque formations by EV71. Viral inhibition of siRNA transfected RD cells was still evident after 48 h. In addition, no significant adverse off-target silencing effects were observed. These results demonstrated the potential and feasibility for the use of siRNA as an antiviral therapy for EV71 infections.  相似文献   
7.
成人下凳骨第三磨牙阻生关系的研究   总被引:1,自引:0,他引:1  
目的 观测成人下颌骨第三磨牙的阻生关系。方法 根据吴氏《人类骨骼测量方法》中规定的年龄估计及性别鉴定的标准,观测成人颌骨的形态结构。结果 302个下颌骨标本的观察结果为,男女混合阻生率为10.60%,女性阻生率高于男性,肉眼见无第三磨牙萌出者106例,经X线拍片验证,5例有埋没牙存在,故实际第三睡缺如率为33.44%。从测量数据可见阻生组(无第三磨牙组)的第二磨牙后间隙、下颌斜长、下颌体长及髁突间宽均较正常组小。结论 无第三磨牙可能是人类进化过程中,下颌骨与牙齿均衡退化的结果,而阻生是人类进化从有第三磨牙向第三磨牙演化的过渡阶段。  相似文献   
8.
This comparative study was conducted to determine the anthropometric measurements and body composition of football teams in the UK and Malaysia. A total of 32 footballers from two teams were studied. The teams were the St Mary's University team (UK) and the Selangor Reserved League team. The height and body weight of the subjects were measured using SECA digital balance with height attachment. Skinfold thickness measurements were taken using Harpenden skinfold callipers at four sites (biceps, triceps, subscapular and suprailiac) and the VO2max of the subjects was estimated by participation in a multi-stage 20m shuttle-run test. The UK team were significantly heavier (p<0.05), taller (p<0.05) and had a higher body fat content (p<0.05) than their Malaysian counterpart. There was no significant difference in VO2 max between the two teams, with the Malaysians recording a slightly higher VO2 max. With regard to playing position, the defenders were found to be the most physically robust and yet had the highest VO2 max, whilst the midfielders had the lightest body weights. More data on the body composition and nutritional status of Malaysian footballers would allow adjustments to be made to dietary intakes and training levels in order to obtain maximum performance throughout the football season.  相似文献   
9.
9例小儿尸检病例的临床与病理诊断作对照分析。结果显示:14例误诊,误诊率为1772%;在~28d,~5岁,~10岁和~14岁4个小儿年龄组中,新生儿组误诊率为2963%,明显高于其他年龄组(P<0.05),且日龄越小误诊率越高;呼吸系统疾病是误诊的主要病种,占4286%;而年长儿的2例误诊均为结核病。提示对新生儿疾病诊断时,要详细了解围生期情况,积极寻找原发病;结核病对儿童的致命威胁应引起儿科医生的高度重视。  相似文献   
10.
OBJECTIVE: To evaluate the effectiveness of general practitioner patient lists as a means of recruiting women to mammography screening. DESIGN: This study constitutes the first part of a comparative study of two alternative recruitment strategies involving invitation of women identified from: (i) general practitioner lists; and (ii) the electoral roll. SETTING AND SUBJECTS: The subjects were women aged 50-64 listed as patients of the first three private practices that agreed to collaborate with the South Australian (SA) Breast X-Ray Service to recruit by this method. These practices include five locations encompassing a spread of middle and upper class socioeconomic areas in Adelaide's southern suburbs. INTERVENTIONS: In all, 1505 women who had not already attended the SA Breast X-Ray Service were sent a letter of invitation by their general practitioner to attend the Service for a screening mammogram at a specified date and time. MAIN OUTCOME MEASURES: The primary outcome measures were eligibility status (eligible, not eligible) and attendance status (attended, cancelled appointment, failed to attend without notice). RESULTS: Excluding 34 letters that were returned unopened, 10% of invitees were classified as not eligible, mostly because they had had a recent mammogram elsewhere. Of the remaining invitees, 68.6% attended, 8.4% rang to cancel the appointment and 23% failed to attend without prior notice. CONCLUSIONS: This method of recruitment is viable, and it yields high participation rates close to the "Health for All Australians" target of 70% for mammography screening. Furthermore, the actual attendance rate for this population is expected to increase over time, because some of those initially classified as ineligible, or who cancelled or failed to attend, eventually will attend. The success of this method of recruitment will be measured against the relative cost and effectiveness of the electoral roll alternative, currently under investigation by the SA Breast X-Ray Service.  相似文献   
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