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11.
de Groot J Kruijt L Scholten JW Boersma WJ Buist WG Engel B van Reenen CG 《Immunology》2005,115(4):495-505
The capacity of farm animals to produce cytokines could be an important determinant of robustness and health. From research in rodents and humans it appears that the production and the balance of T helper 1 (Th1) and T helper 2 (Th2)-type cytokines influences susceptibility to autoimmune and infectious diseases. It is known that pigs show a large variation in many immune response parameters. So far the extent of individual variation in the production of Th1- and Th2-type cytokines in commercial outbred pigs has not been reported. In the current experiment we determined mRNA expression, as well as protein production of cytokines in 32 pigs from eight litters. From each litter two male and two female pigs were tested at 2, 5 and 8 weeks of age. Two Th1-type cytokines, interleukin (IL)-2 and interferon (IFN)-gamma, and two Th2-type cytokines, IL-4 and IL-10, were measured after phytohaemagglutinin (PHA)-stimulation of blood mononuclear cells. Cytokine production and the Th1/Th2-ratio were highly variable. The variation in cytokine protein production was moderately consistent across ages, i.e. pigs that produced high levels of cytokine at 2 weeks of age tended to do so as well at 5 and 8 weeks of age. Cytokine production tended to increase with age, and gilts and boars differed in their IL-2/IL-4 ratio. Unexpectedly, age, gender and litter effects often differed for mRNA and protein production data. We hypothesize that cytokine production is a consistent trait in pigs, especially at the protein production level. Future investigations in more animals and across a wider age range are necessary. 相似文献
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O. E. Scholten H. Paul D. Peters J. W. M. Van Lent R. W. Goldbach 《Archives of virology》1994,136(3-4):349-361
Summary Mechanisms of resistance to beet necrotic yellow vein virus (BNYVV) were studied by comparing the multiplication and distribution of BNYVV in root tissue of some beet accessions. Seedlings were infected either by soil containing resting spores ofPolymyxa betae with BNYVV, or by a viruliferous zoospore suspension. With both inoculation methods high virus concentrations were obtained in rootlets of the susceptible cultivar Regina. Using infested soil, low virus concentrations were found in the partially resistant cultivar Rima and in the resistant accessions Holly and WB42. When a zoospore suspension was used, similar virus concentrations occurred in Rima and Holly as in Regina, while a low virus concentration was found in WB42. By in situ localisation studies, using immunogold-silver labelling, virus was detected in Regina after infection by soil or a zoospore suspension, but it could only be detected in the resistant accessions after infection by a zoospore suspension. In rootlets of Regina, Rima and Holly, virus was found in the epidermis, cortex parenchyma, endodermis, and interstitial parenchyma, but in general not inside the vascular tissue. In WB42 the virus, occurring in small aggregates, seemed to be restricted to the epidermis and some cortex parenchyma cells. Comparing both the multiplication and distribution of BNYVV in rootlets of the accessions studied, it is concluded that the virus resistance mechanism in Rima and Holly is different from that in WB42. 相似文献
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Melchers P Maluck A Suhr L Scholten S Lehmkuhl G 《Restorative neurology and neuroscience》1999,14(2-3):153-160
Survived traumatic brain injuries (TBI) are one of the most serious challenges to the patient's future life. Recent literature increasingly questions the long believed protective effects of functional cerebral plasticity in children. Although TBI in children and adolescents is frequent, they are less frequently admitted to rehabilitation centers as in-patients than adults. This emphasizes the role of out-patient treatment. The progressing study described here aims to achieve a contribution to a comprehensive approach in TBI-rehabilitation for youngsters. A two-stage multimethodal program, starting with stimulation in coma while the patient is on the intensive care unit, and neuropsychological therapy after regaining consciousness is to be evaluated in a controlled, prospective and randomized study. After including nearly 50 % of the planned sample (100 persons), some preliminary results can be mentioned with all applicable caution. The effectiveness of the applied therapy can be stated here with respect to the posttraumatic development of intellectual abilities in the 6- and 12 months follow ups. Moreover, in the control group development of psychopathological alterations was found to a considerable degree and also lower ratings in a quality of life questionnaire, compared to the experimental group. It is expected to prove these differences statistically, after the total sample has been included, and thus equal distributions have been achieved in all predictive variables. 相似文献
14.
Arikawa K Mizuno S Scholten DG Kinoshita M Seki T Kitamoto J Stavenga DG 《Vision research》1999,39(1):1-8
The distal photoreceptors in the tiered retina of Papilio exhibit different spectral sensitivities. There are at least two types of short-wavelength sensitive receptors: an ultraviolet receptor with a normal spectral shape and a violet receptor with a very narrow spectral bandwidth. Furthermore, a blue receptor, a double-peaked green receptor and a single-peaked green receptor exist. The violet receptor and single-peaked green receptor are only found in ommatidia that fluoresce under ultraviolet illumination. About 28% of the ommatidia in the ventral half of the retina exhibit the UV-induced fluorescence. The fluorescence originates from an ultraviolet-absorbing pigment, located in the most distal 70 microns of the ommatidium, that acts as an absorption filter, both for a UV visual pigment, causing the narrow spectral sensitivity of the violet receptor, and for a green visual pigment, causing a single-peaked green receptor. 相似文献
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Barriers to access to opioid medicines for patients with opioid dependence: a review of legislation and regulations in eleven central and eastern European countries
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David ST Chandran U Paquette D Scholten D Wilson J Galanis E Becker M Crane F Lester R Mersereau T Wong E Carr D 《Chronic diseases in Canada》2005,26(2-3):59-64
Attendance at summer outdoor mass gatherings may lead to heat- and sun-related illness. The purposes of this study were: (1) to estimate the proportion of people in attendance at the 2003 Canada Day celebration in the National Capital Region who used sun and heat protective items; (2) to identify factors associated with the utilization of these protective items; and (3) to provide research data to public outdoor event organizers when developing evidence-based plans for safer events. A naturalistic observational cross-sectional method was used to gather information at the 2003 Canada Day celebration in the National Capital Region on attendees' demographics, the sun and heat protective items they used and the protective resources available at the event sites. Of the 398 observed attendees, the proportion using any one of the protective items ranged from 3 percent (an open umbrella) to 51.5 percent (sunglasses). Females were more likely to use protective items more than males, and adults more likely than children. Planners of public outdoor events should consider the factors that influence the utilization of sun and heat protective behaviours and the environmental modifications that would allow participants to make safe choices. 相似文献
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