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Mycoplasma hyopneumoniae (Mh) is the primary agent of porcine enzootic pneumonia (PEN), a chronic respiratory disease endemic to pig farms, and characterized histologically by infiltration of mononuclear cells in airways and prominent hyperplasia of the bronchus-associated lymphoid tissue (BALT). To gain further insight into the pathogenesis of PEN, cytokine expression in the lung, with particular attention to the BALT, was examined immunohistochemically in pigs naturally infected with Mh. An increase (P < 0.05) in proinflammatory and immunoregulatory cytokines (especially interleukin [IL]-2, IL-4 and tumour necrosis factor [TNF]-alpha, and to a lesser extent IL-1 [alpha and beta] and IL-6) was detected in the BALT, which showed intense lymphoid hyperplasia. IL-1beta and TNF-alpha were also detected in the bronchoalveolar exudate of infected pigs, and IL-6 and IL-8 were demonstrated in mononuclear cells of the alveolar septa. The results showed that in Mh infection, macrophage and lymphocyte activation results in the expression of a number of cytokines capable of inducing lung lesions and lymphoreticular hyperplasia of the BALT.  相似文献   
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We have developed small-volume (50 or 250 μl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes.  相似文献   
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Incidence of the Carnation etched ring virus (CERV), the only DNA virus reported to date on carnation, was investigated by a bioassay using a partially purified virus as inoculum and then by a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Out of 61 carnation cultivars analyzed 41 (67%) were found positive. The virus positivity was verified by polymerase chain reaction (PCR) and nucleotide sequencing. The amplified 1349 bp fragment was by about 98% and 96% identical with respect to coat protein (CP) and enzymatic polyprotein genes, respectively, as compared to the sequences available in the database. In terms of amino acid sequence similarity, the homology values were 99% and 97%, respectively. Comparison with other caulimoviruses revealed that CERV is most closely related to the Cauliflower mosaic virus (CaMV). High genetic stability of CERV may be attributed to the fact that it has evolved from the same initial sequence in an original host. Because of global market of cut flowers and vegetative propagation it has been dispersed around the world.  相似文献   
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ObjectivesTo examine the effectiveness of game-based interventions compared with usual care on health-related outcomes for acutely hospitalized older patients.DesignSystematic review of randomized controlled trials (RCT) and nonrandomized trials.Setting and ParticipantsAdults aged 65 years or older admitted to an Acute Care for Elderly unit were selected.MeasuresHealth-related outcomes (eg, functional capacity, quality of life, adherence to treatment).ResultsFour RCTs were included in the review. The interventions were based on the implementation of serious-game programs using Nintendo Wii in acute medical patients. Across the included studies, no significant differences were observed between groups on functional capacity and health-related quality of life. Significant differences were found between groups on the adherence to treatment (in favor of the control group), but no differences were obtained in other outcomes such as enjoyment and motivation.Conclusions and ImplicationsIn general, there is very limited evidence for the efficacy to reach conclusions about the effects of game-based interventions on health-related outcomes in acutely hospitalized older patients. Future studies are needed to improve our knowledge in the field; however, we consider that these strategies should be considered in the future complementary to usual care.  相似文献   
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Prevention Science - An earlier trial of a school-based, preventative intervention, HealthWise South Africa, demonstrated some efficacy in preventing adolescent drinking and smoking in the Western...  相似文献   
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Archives of Sexual Behavior - Sex during adolescence is normative; however, there are substantial individual differences in the timing and context of sexual debut. Leisure boredom is an...  相似文献   
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The provision of continuous care to a dependent person can lead to a lack of self-care by the caregiver themselves with corresponding low levels of well-being. This well-being has been analysed mostly from within the perspective of the hedonic tradition, with the development of personal growth often being overlooked. This study aims to increase the understanding of the connection between this type of psychological well-being and involvement in self-care activities, and to be a starting point for the determination of categories that may serve in the screening of potential participants in social-health interventions where it is being promoted. Taking the hypothesis of a probable positive connection between psychological well-being and involvement in self-care, an observational study was carried out on 45 caregivers of relatives with dementia. In those caregivers showing greater dedication to self-care, a higher score was obtained on the well-being scales connected to personal significance and positive emotions and experiences. These findings were further reinforced by the identification of other positive connections, the involvement in self-care and the six dimensions of wellness contemplated by Ryff. It is possible to envisage the existence of a virtuous circle in respect of the caregiver, whereby a greater involvement in self-care is related to a higher psychological well-being, which in turn is related to greater self-care, and so on.  相似文献   
30.
Genes expressed in a stage-specific manner may help us understand the molecular events controlling the complex life cycle of schistosomes. cDNA and genomic clones encoding a calcium-binding protein (CaBP) were obtained from cercariae and their sequence determined. The encoded protein (69 amino acids long) shows clear resemblance to the domain structure and organization of CaBP molecules. It contains two typical calcium-binding loops, the distance between which is identical to the length conserved in other CaBP molecules. In addition, the schistosome CaBP shows Ca2+-dependent electrophoretic mobility (increased with Ca2+-ions and decreased with EGTA). Northern blots revealed expression of the CaBP gene in cercariae but not in sporocyst or worm (developmental stages preceding and following cercaria). The preferential expression of this CaBP in the cercaria raises questions as to what cercaria-specific function(s) it performs. The structure of the gene is similar to that in other eukaryotes, and one intron interrupts the coding sequence. The region of the cap site was determined, and there was no evidence of the spliced leader sequence found in the mRNAs of other parasites. The CaBP reveals a rapid change in gene expression, since the mRNA is missing in the parasite residing in infected snails, but is readily detected in cercariae 1 h after shedding. We identified other genes which are turned on (like the CaBP) or shut off within the short period of transition from cercariae in the snail to free-swimming cercariae.  相似文献   
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