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61.

Background  

Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology.  相似文献   
62.
目的:采用SF-36量表中文版评价农村中老年人生存质量,并为提高农村中老年人的生存质量和健康水平提供科学依据和建议。方法:采用随机抽样的方法,采用面对面访谈的形式,记分方法参照国际生存质量评价计划(IQOLA)的制定标准,评价其生理和心理健康状况。结果:1590名农村中老年人男性生存质量得分高于女性。经济水平对农村中老年人的生理健康的影响大于对其心理健康的影响。配偶健在的农村中老年人的各维度得分均高于无配偶者。农村中老年人的各维度得分随教育水平的升高呈升高趋势。结论:农村中老年人的生存质量与年龄成负相关,同时也受文化程度和经济水平等多个因素的影响。因而,对农村中老年人这一弱势群体应该给予更多关注。  相似文献   
63.
The fate of tetanus toxin (mol wt 150,000) subsequent to its retrograde axonal transport in peripheral sympathetic neurons of the rat was studied by both electron microscope autoradiography and cytochemistry using toxin-horseradish peroxidase (HRP) coupling products, and compared to that of nerve growth factor (NGF), cholera toxin, and the lectins wheat germ agglutinin (WGA), phytohaemagglutinin (PHA), and ricin. All these macromolecules are taken up by adrenergic nerve terminals and transported retrogradely in a selective, highly efficient manner. This selective uptake and transport is a consequence of the binding of these macromolecules to specific receptive sites on the nerve terminal membrane. All these ligands are transported in the axons within smooth vesicles, cisternae, and tubules. In the cell bodies these membrane compartments fuse and most of the transported macromolecules are finally incorporated into lysosomes. The cell nuclei, the parallel golgi cisternae, and the extracellular space always remain unlabeled. In case the tetanus toxin, however, a substantial fraction of the labeled material appears in presynaptic cholinergic nerve terminals which innervate the labeled ganglion cells. In these terminals tetanus toxin-HRP is localized in 500-1,000 A diam vesicles. In contrast, such a retrograde transsynaptic transfer is not at all or only very rarely detectable after retrograde transport of cholera toxin, NGF, WGA, PHA, or ricin. An atoxic fragment of the tetanus toxin, which contains the ganglioside-binding site, behaves like intact toxin. With all these macromolecules, the extracellular space and the glial cells in the ganglion remain unlabeled. We conclude that the selectivity of this transsynaptic transfer of tetanus toxin is due to a selective release of the toxin from the postsynaptic dendrites. This release is immediately followed by an uptake into the presynaptic terminals.  相似文献   
64.
Bacterial Flora from external surface and alimentary canal of wild and laboratory strains of Culex pipiens were isolated and investigated using quantitative bacterial cultures. Individual colonies were subcultured and identified to species level. Counts from alimentary canal differ significantly from those of the external surface. An increase in bacterial density was detected after feeding on mammalian and avian blood meal. Bacterial identification revealed a complex bacterial flora. In addition to members of family Enterobacteriaceae species of Bacillus, Staphylococcus, Streptococcus, and Acinetobacter are the most common in both strains investigated. Gram negative bacteria were increased significantly after feeding on blood meals than those detecting during the feeding on sugar after emergence of the adult female mosquitoes and vise versa with Gram positive bacteria. Bacterial isolates were tested for resistance to the most common commercial antibiotics.  相似文献   
65.
Some Egyptian isolates of Bacillus thuringiensis (BT) were grown on economic media contain 4% of fodder yeast in tap water and incubated under shaking conditions for four days. The biological activities of these isolates against Culex pipiens (Diptera: Culicidae) were carried out to determine their effectiveness against field and laboratory strains of 3rd larval instar. All isolates of BT were more pathogenic to laboratory strain. causing up to 84% larval mortality. The insecticidal activities of these isolates were extended to the pupal stage causing a significant effect on pupal mortality in both strains tested. A pronounced effect on adult emergence was noticed with remarkable adult malformations especially in the case of the isolate No. 2. The reproductivety of females was affected significantly by all isolates applied.  相似文献   
66.
Despite the obvious benefit of an immune system, its efficacy against pathogens and parasites may show great variation among individuals, populations and species. Understanding the causes of this variation is becoming a central theme in ecology. Many biotic and abiotic factors are known to influence immunocompetence (temperature, age, etc.). However, for a given age, size among individuals varies, probably as a result of accumulated resources. Thus, these variable resources could be allocated to immune defence and, consequently, body size may explain part of the variation in immune responsiveness. However, the influence of body size on immune defence is often overlooked. The present study investigates variations in haemocyte count and phenoloxidase activity in larvae of the phytophagous vine moth Eupoecilia ambiguella Hübner of the same age, although differing in body size. The measurements of immune function are made both when the insects are immunologically naïve and 24 h after a bacterial immune challenge. The base levels of these immune parameters do not covary with body size in naïve larvae. After the bacterial immune challenge, more haemocytes and phenoloxidase enzyme are mobilized, and the mobilization of these immune effectors is correlated positively with individual body size. Thus, larger larvae exhibit higher immunocompetence than smaller ones, suggesting that smaller larvae might be more vulnerable to infection. These results suggest that body size is probably an underestimated variable, which nevertheless modulates the insect immune system and should thus be considered as a covariate in insect immune system measurement. It is recommended therefore, that body size should be taken into account in ecological immunity studies with insects. © 2013 The Royal Entomological Society  相似文献   
67.
Many animals have individual and social mechanisms for combating pathogens. Animals may exhibit short-term physiological tradeoffs between social and individual immunity because the latter is often energetically costly. Genetic tradeoffs between these two traits can also occur if mutations that enhance social immunity diminish individual immunity, or vice versa. Physiological tradeoffs between individual and social immunity have been previously documented in insects, but there has been no study of genetic tradeoffs involving these traits. There is strong evidence that some genes influence both innate immunity and behaviour in social insects – a prerequisite for genetic tradeoffs. Quantifying genetic tradeoffs is critical for understanding the evolution of immunity in social insects and for devising effective strategies for breeding disease-resistant pollinator populations. We conducted two experiments to test the hypothesis of a genetic tradeoff between social and individual immunity in the honey bee, Apis mellifera. First, we estimated the relative contribution of genetics to individual variation in innate immunity of honey bee workers, as only heritable traits can experience genetic tradeoffs. Second, we examined if worker bees with hygienic sisters have reduced individual innate immune response. We genotyped several hundred workers from two colonies and found that patriline genotype does not significantly influence the antimicrobial activity of a worker’s hemolymph. Further, we did not find a negative correlation between hygienic behaviour and the average antimicrobial activity of a worker’s hemolymph across 30 honey bee colonies. Taken together, our work indicates no genetic tradeoffs between hygienic behaviour and innate immunity in honey bees. Our work suggests that using artificial selection to increase hygienic behaviour of honey bee colonies is not expected to concurrently compromise individual innate immunity of worker bees.  相似文献   
68.
Chalcone derivatives have been synthesized by reaction of 1-(2,5-dimethyl-furan-3-yl)-ethanone with corresponding active aldehyde in ethanolic NaOH in microwave oven. The structure of these compounds was established by elemental analysis, IR, 1H NMR, 13C NMR, and EI-MS spectral analysis. The anti-bacterial activity of these compounds was first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) was determined with the reference of standard drug chloramphenicol. The results showed that pyrazol containing chalcone (compound 8) inhibited both types of bacteria (Gram-positive and Gram-negative) better than chloramphenicol.  相似文献   
69.
This study evaluated how water temperature (26, 28, and 30°C), number of meals per day (one or two meals), and protein percent in diet (20, 25 and 30%) impact growth performance, biometric indices, and feeding behavior of Nile tilapia, Oreochromis niloticus. Fish were randomly allocated into 18 equal replicate groups. Higher final body weight was observed in fish reared at 30°C and fed one meal per day containing 30% crude protein. Better weight gain, weight gain %, feed conversion ratio, specific growth rate, and condition factor were recorded in fish reared at 26°C and fed one meal per day containing 30% protein. The best length weight relationship was obtained in fish reared at 26°C and fed one meal per day containing 30% crude protein. Shorter feeding duration and duration of appetite inhibition latency were recorded in fish reared at 30°C, fed one meal per day, and given a diet containing 30% protein. The highest proactivity was recorded in fish reared at 30°C, received one meal per day, and with 25% crude protein in their diet. Conclusively, rearing Nile tilapia at 26–30°C with a lower feeding frequency (one meal/day) and a 30% crude protein diet achieved better performance and feeding behavior.  相似文献   
70.
Leptin and μ-calpain have been considered as two candidate genes for carcass performance and meat quality traits in the farm animals. The micromolar calcium-activated neutral protease (CAPN1) gene encodes μ-calpain that degrades myofibril proteins under the postmortem conditions which appears to be the primary enzyme in the postmortem tenderization process. Leptin is the hormone product of the obese (LEP) gene. The role of leptin as a lipostatic signal regulating whole-body energy metabolism makes it one of the best physiological markers of body weight, food intake, reproduction and immune system functions.Genomic DNA extracted from 100 healthy buffaloes was amplified using primers that were designed from the cattle CAPN1 and LEP gene sequences. The amplified fragments of CAPN1 obtained from all tested buffalo DNA at 670-bp were digested with FokI endonuclease. The result showed that all tested buffaloes are genotyped as CC for CAPN1. For LEP gene, the amplified fragments obtained from all tested buffalo DNA at 400-bp were digested with Sau3AI endonuclease. All buffalo animals investigated in the present study are genotyped as AA for LEP gene.  相似文献   
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