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41.
To find out the infection efficiency of recombinant adeno-as sociated virus 2-mediated exogenou s genes in human peripheral blood monocyte-derived dendritic cells(D Cs),the process of transfection wa s investigated by FITC-labeled rAA V2,and observed under confocal mic roscope.Newly separated dendritic cells were tranfected by rAAV2-luc and rAAV2-GFP at different MOI,and transfection efficiency were detec ted by luminometer for rAAV2-luc a nd flow cytometry for rAAV2-GFP.Th e results were elucidated in four different assay systems:(1)60min w as needed for rAAV2 to bind on den dritic cells,and got into cells in the following 10min;(2)the express ion of luc could be detected at th e MOI as low as 1×10~5v.g/cell,and the expression plateau was reached by the MOI of 10~6~10~7v.g/cell,furt her increase of MOI had no functio n on expression level;(3)transgene expression was detected after 48h, and maintained a higher expression level from 96h to 240h after infec tion;(4)7days postinfection of rAA V2-GFP,5%~18% dendritic cells were GFP positive. These data suggest th at rAAV2 vector can efficiently in fect monocyte-derived dendritic ce lls and mediate exogenous gene exp ression,and that the application o f rAAV2 as vector may be useful fo r gene transfer to dendritic cells in ex vivo immunotherapy.  相似文献   
42.
We evaluated the cooling rate of hyperthermic subjects, as measured by rectal temperature (T(re)), during immersion in a range of water temperatures. On 4 separate days, seven subjects (4 men, 3 women) exercised at 65% maximal oxygen consumption at an ambient temperature of 39 degrees C until T(re) increased to 40 degrees C (45.4 +/- 4.1 min). After exercise, the subjects were immersed in a circulated water bath controlled at 2, 8, 14, or 20 degrees C until T(re) returned to 37.5 degrees C. No difference in cooling rate was observed between the immersions at 8, 14, and 20 degrees C despite the differences in the skin surface-to-water temperature gradient, possibly because of the presence of shivering at 8 and 14 degrees C. Compared with the other conditions, however, the rate of cooling (0.35 +/- 0.14 degrees C/min) was significantly greater during the 2 degrees C water immersion, in which shivering was seldom observed. This rate was almost twice as much as the other conditions (P < 0.05). Our results suggest that 2 degrees C water is the most effective immersion treatment for exercise-induced hyperthermia.  相似文献   
43.
The reporting of child sexual abuse (CSA) and physician-patient sexual relationships (PPSR) are currently the focus of professional, legal and media attention in several countries. This paper briefly reviews mental health policies on these issues and reports on a WPA survey of them. While the WPA Madrid Declaration permits breaching confidentiality for mandatory reporting of CSA and clearly prohibits PPSR, it is not known how or to what extent these policies are implemented in WPA Member Societies’ countries. It is also not known whether policies or laws exist on these topics nationally or to what extent psychiatrists and the public are aware of them. Representatives of WPA Member Societies were e-mailed a survey about issues pertaining to CSA and PPSR. Fifty-one percent of 109 countries replied. All reporting countries had laws or policies regarding the reporting of CSA, but this was often voluntary (63%) and without protection for reporting psychiatrists either by law (29%) or by Member Societies (27%). A substantial number of psychiatric leaders did not know the law (27%) or their Society’s policy (11%) on these matters. With respect to PPSR, some reporting countries lacked laws or policies about PPSR with current (17%) or past (56%) patients. Fewer than half of responding representatives believed that their Society’s members or the public were well informed about the laws and policies pertaining to CSA or PPSR. There is clearly a wide range of laws, policies and practices about CSA and PPSR in WPA Member Societies’ countries. There is a need in some countries for laws or supplemental policies to facilitate the protection of vulnerable child and adult patients through clear, mandatory reporting policies for CSA and PPSR. Mechanisms to protect and support reporting psychiatrists should also be developed where they do not already exist. There is also a need in some countries to develop strategies to improve the education of psychiatrists, trainees, and the public on these issues.The Asia-Pacific region has close to half of the estimated 450 million people affected by mental illness globally 1.Based on international mental health care benchmarks, many Western health systems have established contemporary health policy and guidelines which include the provision of mental health care in the community. However, the delivery of quality and appropriate community mental health care remains an ongoing challenge for countries of both high and low socio-economic level. Difficulties and obstacles in implementation of comprehensive community service models include inadequate funding, availability of trained mental health workforce, integration with primary care services and community agencies, and collaboration between public and private health systems 2 - 3. As community mental health service system depends on sufficient workforce for service delivery, the critical shortage of adequately trained mental health staff continues to impede the progress of mental health reform.In response to such global trends, many countries in the Asia-Pacific region have begun to establish mental health policy and guidelines to move from institutional care to community mental health services. While these reforms are supported by recommendations from the World Health Organization (WHO) governing bodies, such as the Western Pacific Regional Mental Health Strategy 4, social, economic and cultural factors in Asia-Pacific countries often do not allow ready translation of Western community mental health models of care. Governments and service providers commonly face challenges in the development and implementation of locally appropriate community mental health care and services. Additionally, it would be unrealistic or undesirable to produce rigid recommendations for a singular community mental health care model, due to the diversity across the Asia-Pacific region. Hence, for constructive change to occur in the region, innovative, culturally appropriate and economically sustainable pathways for community treatment models need to be explored, developed and shared. Community mental health service reform appears to be gaining momentum in this region, despite the obstacles. Valuable lessons and inspiration for further development can be gained from both the successes and difficulties in reforming mental health systems and practices in the region.An emerging network of representatives from governments, peak bodies and key organizations is emerging in the Asia-Pacific region to build supportive relationships in order to facilitate the implementation of locally appropriate policy frameworks for community mental health service reform. The network is supported by the Asia-Pacific Community Mental Health Development (APCMHD) project, which involves 14 countries/regions in the Asia-Pacific region. Initiated in collaboration with the WHO Western Pacific Regional Office, the APCMHD project is led by Asia-Australia Mental Health, a consortium of the University of Melbourne Department of Psychiatry and Asialink, and St. Vincent’s Health, which is a part of the WHO Collaborating Centre for Mental Health (Melbourne). The project, which brought many key mental health organizations to work collaboratively, is consistent with the WHO Global Action Programme for Mental Health 5.The project aims are to promote best practice in community mental health care through exchange of knowledge and practical experience in the Asia-Pacific region. The key outcome is the documentation of the current status, strengths and needs of community mental health services in the region, in the hope to translate current understanding into practical changes in the future.  相似文献   
44.
The synthesis and the biological evaluation of new potent phosphodiesterase type 4 (PDE4) inhibitors are presented. This new series was elaborated by replacement of the metabolically resistant phenyl hexafluorocarbinol of L-791,943 (1) by a substituted aminopyridine residue. The structure-activity relationship of N-substitution on 3 led to the identification of (-)-3n which exhibited a good PDE4 inhibitor activity (HWB-TNFalpha=0.12 microM) and an improved pharmacokinetic profile over L-791,943 (rat t(1/2)=2 h). (-)-3n was well tolerated in ferret with an emetic threshold of 30 mg/kg (po) and was found to be active in the ovalbumin-induced bronchoconstriction model in guinea pig (54%, 0.1 mg/kg, ip) as well as the ascaris-induced bronchoconstriction model in sheep (64%/97%, early/late, 0.5 mg/kg, iv).  相似文献   
45.
报道发现于海南省鹦哥岭的粗叶木属(Lasianthus Jack)海南省新记录种5种,并描述了它们的主要辨认特征。其中4种(华南粗叶木Lasianthus austrosinensis H.S.Lo、长梗粗叶木L.filipes Chun ex H.S.Lo、西南粗叶木L.henryi Hutch.、台湾粗叶木L.formosensis Matsum.)在与海南邻近的广东省与广西壮族自治区均有记录,而大叶粗叶木L.rigidus Miq.则在热带亚洲具有明显的间断性分布。  相似文献   
46.
为探讨细胞因子基因(人IL-2、IL-6)转导对于肿瘤细胞膜MHC抗原及细胞膜糖蛋白表达调控的影响,本文利用脂质体介导的方法,将含人IL-6、IL-2基因的逆转录病毒载体分别导入人乳腺癌细胞系MCF-7细胞中,采用间接免疫荧光染色流式细胞仪测定法,对基因转导的瘤细胞细胞膜糖蛋白及MHC抗原表达进行测定。结果表明经两种基因修饰的MCF-7细胞MHCⅠ型抗原表达均获得增强,此外,基因转导细胞可程度不同地表现出细胞膜多种糖蛋白表达的变化。提示肿瘤细胞膜抗原及糖蛋白表达的改变可能是细胞因子基因转导影响肿瘤细胞免疫原性的重要结构基础。  相似文献   
47.
华西银腊梅挥发油化学成分的研究   总被引:1,自引:0,他引:1  
用水蒸气蒸馏法提取华西银腊梅挥发油,并用气相色谱-质谱(GC-MS)联用技术对其挥发油的化学成分进行分析,结果共鉴定了其中的39种成分,所鉴定成分含量约占总检出量的87.83%。其化学成分主要为(Z,Z)-9,12-十八碳二烯酸甲酯(9.00%),壬醛(5.83%),二十一烷(5.69%),二十烷(5.08%),辛炔酸(4.50%),2,6,10,15-四甲基十七烷(3.93%),(Z)-6-十八烯酸甲酯(3.65%),3,8-二甲基十一烷(3.52%),1-十六碳炔(3.31%),肉豆蔻酸(2.86%),月桂醛(2.81%),壬酸(2.23%),5,6,7,7α-四氢-4,4,7α三甲基-2(4H)-苯并呋喃酮(2.18%)等。  相似文献   
48.
海南俄贤岭石灰岩山地海南大戟灌丛群落研究   总被引:4,自引:0,他引:4  
根据样方调查,对海南俄贤岭自然保护区海南大戟灌丛群落的种类组成、外貌、结构特征和物种多样性进行分析。结果表明,在700m2样地中,有维管植物77种,隶属于47科70属。群落中乔木的个体数量很少,主要由灌木和草本组成,灌木层主要优势种为海南大戟等。群落外貌常绿,生活型以小高位芽为主,占22.08%;按照Raunkiaer的频度等级定律,属于B级的种类最多,频度值为43.42。整个群落的物种丰富度Magarlef指数为8.56,Shannon-Wiener指数为1.38,Simposon为0.90,均匀度指数为0.32。群落各层次的丰富度格局表现为灌木层>草本层>乔木层>藤本植物,多样性格局为灌木层>乔木层>草本层<(>)藤本植物,均匀度格局为乔木层>藤本植物>灌木层>草本层。  相似文献   
49.
Background. Integrins are transmembrane αβ heterodimer receptors that function as structural and functional bridges between the cytoskeleton and ECM (extracellular matrix) molecules. The RGD (arginine‐glycine‐aspartate tripeptide motif)‐dependent integrin α8β1 has been shown to be involved in various cell functions in neuronal and mesenchymal‐derived cell types. Its role in epithelial cells remains unknown. Results. Integrin α8β1 was found to be expressed in the crypt cell population of the human intestine but was absent from differentiating and mature epithelial cells of the villus. The function of α8β1 in epithelial crypt cells was investigated at the cellular level using normal HIECs (human intestinal epithelial cells). Specific knockdown of α8 subunit expression using an shRNA (small‐hairpin RNA) approach showed that α8β1 plays important roles in RGD‐dependent cell adhesion, migration and proliferation via a RhoA/ROCK (Rho‐associated kinase)‐dependent mechanism as demonstrated by active RhoA quantification and pharmacological inhibition of ROCK. Moreover, loss of α8β1, through RhoA/ROCK, impairs FA (focal adhesion) complex integrity as demonstrated by faulty vinculin recruitment. Conclusions. Integrin α8β1 is expressed in epithelial cells. In intestinal crypt cells, α8β1 is closely involved in the regulation of adhesion, migration and cell proliferation via a predominant RhoA/ROCK‐dependent mechanism. These results suggest an important role for this integrin in intestinal crypt cell homoeostasis.  相似文献   
50.
Transmission of plant viruses by aphid vectors   总被引:10,自引:0,他引:10  
  相似文献   
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