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21.
A method of radiometry in vivo was applied to study the regularities attending distribution of the absorbed dose and its formation in the course of one year after the administration of 0.033 muCu/g of selenomethionine-75Se to rats, as well as the functional condition of the adaptive hypophysis-adrenal glands system by the determination of plasma corticosterone. A high tropicity of this preparation to the endocrine system organs was demonstrated. Intensification of the functional activity of the adaptive system was indicated by an increase of the blood plasma corticosterone concentration following the administration of a, radioactive preparation and its statistically significant increase (in comparison with control) 3, 6, and 10 months from the beginning of the experiment. The action of acute stress (histamine and formalin) 10 months after the administration of selenomethionine-75Se caused no sharp elevation of the plasma corticosterone concentration characteristic of control rats, this indicating an extreme strain of the hypophysis-adrenal gland system and its incapacity to respond to additional loads. It is supposed that analysis of functional condition of the adaptive system could serve as the key in the assessment of the biological effect of low radiation doses.  相似文献   
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The recently determined crystal structures of two aspartic proteinase zymogens, prophytepsin from barley and proplasmepsin II from the malarial parasite Plasmodium falciparum, have provided new insights into zymogen inactivation. Prophytepsin shows a variation of the mechanism of inhibition used by the well-known gastric aspartic proteinase zymogens, whereas proplasmepsin II uses a completely new mode of inactivation.  相似文献   
24.
We previously described an enrichment-immunoassay utilizing a T6 monoclonal antibody capture enzyme-linked immunosorbent assay. Here we evaluated it for the rapid screening for Salmonella in fishmeal obtained from the national Animal and Plant Quarantine service in the People's Republic of China. In this method, the number of Salmonella present is first expanded by appropriate enrichment cultures, and the pathogens are then directly detected by the T6 immunoassay. In a total of 94 enrichment cultures of fishmeal, we obtained an overall concordance of 98% between the results obtained in parallel by this method and by conventional test method. The positive prediction by this method was 92% and the negative prediction was 100%. The turn around time for the new test was 27 h which is a significant improvement from the turn around time exceeding 96 h required for the conventional test method. This test proved to be compatible with the routine work flow in the practical setting of a quarantine laboratory.  相似文献   
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We used a nonintrusive field experiment carried out at six sites – Wales (UK), Denmark (DK), the Netherlands (NL), Hungary (HU), Sardinia (Italy – IT), and Catalonia (Spain – SP) – along a climatic and latitudinal gradient to examine the response of plant species richness and primary productivity to warming and drought in shrubland ecosystems. The warming treatment raised the plot daily temperature by ca. 1 °C, while the drought treatment led to a reduction in soil moisture at the peak of the growing season that ranged from 26% at the SP site to 82% in the NL site. During the 7 years the experiment lasted (1999–2005), we used the pin‐point method to measure the species composition of plant communities and plant biomass, litterfall, and shoot growth of the dominant plant species at each site. A significantly lower increase in the number of species pin‐pointed per transect was found in the drought plots at the SP site, where the plant community was still in a process of recovering from a forest fire in 1994. No changes in species richness were found at the other sites, which were at a more mature and stable state of succession and, thus less liable to recruitment of new species. The relationship between annual biomass accumulation and temperature of the growing season was positive at the coldest site and negative at the warmest site. The warming treatment tended to increase the aboveground net primary productivity (ANPP) at the northern sites. The relationship between annual biomass accumulation and soil moisture during the growing season was not significant at the wettest sites, but was positive at the driest sites. The drought treatment tended to reduce the ANPP in the NL, HU, IT, and SP sites. The responses to warming were very strongly related to the Gaussen aridity index (stronger responses the lower the aridity), whereas the responses to drought were not. Changes in the annual aboveground biomass accumulation, litterfall, and, thus, the ANPP, mirrored the interannual variation in climate conditions: the most outstanding change was a decrease in biomass accumulation and an increase in litterfall at most sites during the abnormally hot year of 2003. Species richness also tended to decrease in 2003 at all sites except the cold and wet UK site. Species‐specific responses to warming were found in shoot growth: at the SP site, Globularia alypum was not affected, while the other dominant species, Erica multiflora, grew 30% more; at the UK site, Calluna vulgaris tended to grow more in the warming plots, while Empetrum nigrum tended to grow less. Drought treatment decreased plant growth in several studied species, although there were some species such as Pinus halepensis at the SP site or C. vulgaris at the UK site that were not affected. The magnitude of responses to warming and drought thus depended greatly on the differences between sites, years, and species and these multiple plant responses may be expected to have consequences at ecosystem and community level. Decreases in biodiversity and the increase in E. multiflora growth at the SP site as a response to warming challenge the assumption that sensitivity to warming may be less well developed at more southerly latitudes; likewise, the fact that one of the studied shrublands presented negative ANPP as a response to the 2003 heat wave also challenges the hypothesis that future climate warming will lead to an enhancement of plant growth and carbon sequestration in temperate ecosystems. Extreme events may thus change the general trend of increased productivity in response to warming in the colder sites.  相似文献   
26.
SYNOPSIS. An ultrastructural investigation has been carried out on 180°-rotated ciliary meridians (inverted meridians) in Tetrahymena pyriformis temperature-sensitive mutant (molb/molb), syngen 1, strain B. The longitudinal, transverse and postciliary microtubular bands, the kinetodesmal fiber, and the parasomal sac, are shown to be disposed at a 180° angle to their normal positions or orientations. Other abnormalities are as folows: the first 2 basal bodies of the inverted meridian fail to organize into “couplets” and the inverted meridian intrudes into the anterior pole region; an extra longitudinal microtubular band is found in one of the cell lines.  相似文献   
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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   
29.
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   
30.
Proinflammatory cytokines TNF, IFNG, and IL17 play an important role in eruption of psoriasis. The activation of epidermal keratinocytes with the named cytokines alters their terminal differentiation program and causes their hyperproliferation in the diseased skin. HaCaT cells, which are immortalized human keratinocytes, are often used as a cellular model of psoriasis. The aim of this study was to evaluate changes in gene expression and the proliferation rates in cultured HaCaT cells treated with TNF, IFNG, and IL17. We found that HaCaT cells decrease their proliferation rate in response to either IL17 or a combination TNF and IFNG. The analysis of microarray data discovered a group of 12 genes, which were downregulated in HaCaT after treatments with the named cytokines and upregulated in psoriatic lesional skin. Eight genes were important for DNA replication and they also contributed to two larger networks that regulated cell progression through the cell cycle. We conclude that HaCaT cells have a sufficient limitation as a cellular model of psoriasis due to their treatment with proinflammatory cytokines, namely TNF, IFNG, and IL17 does not increase their proliferation rate. Thus, the studies of psoriasis based on HaCaT cells as an experimental model shall take in account this important phenomenon.  相似文献   
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