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991.
This study investigated the effect of repeated acute restraint stress and high‐fat diet (HFD) on intestinal expression of nutrient transporters, concomitant to intestinal inflammation. The ability of adenosine to reverse any change was examined. Six‐week‐old male Sprague Dawley rats were divided into eight groups: control or non‐stressed (C), rats exposed to restraint stress for 6 h per day for 14 days (S), control rats fed with HFD (CHF) and restraint‐stressed rats fed with HFD (SHF); four additional groups received the same treatments and were also given 50 mg/l adenosine dissolved in drinking water. Fasting blood glucose, plasma insulin, adiponectin and corticosterone were measured. Intestinal expression of SLC5A1, SLC2A2, NPC1L1 and TNF‐α was analysed. Histological evaluation was conducted to observe for morphological and anatomical changes in the intestinal tissues. Results showed that HFD feeding increased glucose and insulin levels, and repeated acute restraint stress raised the corticosterone level by 22%. Exposure to both stress and HFD caused a further increase in corticosterone to 41%, while decreasing plasma adiponectin level. Restraint stress altered intestinal expression of SLC5A1, SLC2A2 and NPC1L1. These changes were enhanced in SHF rats. Adenosine was found to alleviate HFD‐induced increase in glucose and insulin levels, suppress elevation of corticosterone in S rats and improve the altered nutrient transporters expression profiles. It also prevented upregulation of TNF‐α in the intestine of SHF rats. In summary, a combination of stress and HFD exaggerated stress‐ and HFD‐induced pathophysiological changes in the intestine, and biochemical parameters related to obesity. Adenosine attenuated the elevation of corticosterone and altered expression of SLC5A1, NPC1L1 and TNF‐α.  相似文献   
992.
A reversed passive hemagglutination (RPHA) method was developed for the detection of transmissible gastroenteritis (TGE) virus in the fecal specimens from pigs. Ovine erythrocytes fixed with glutaraldehyde and treated with tannic acid were coated with anti-TGE virus swine antibodies, which were purified by affinity chromatographic technique linked with purified TGE virus. The RPHA test was done by the Microtiter method. Erythrocytes coated with purified specific antibodies were agglutinated by TGE virus, but not by porcine rotavirus or porcine enterovirus. The reaction was specifically inhibited by antiserum against TGE virus, confirming the specificity of the reaction. A litter of seven 3-day-old pigs was orally inoculated with TGE virus, and fecal specimens were obtained once a day and serum was obtained every 4th day. With the RPHA test, TGE virus was detected in the diarrheal feces; all of the inoculated pigs developed virus-neutralization antibody for the TGE virus. The RPHA test detected TGE virus in feces from pigs with naturally occurring diarrhea. The RPHA test detected TGE virus in 5 of 6 fecal specimens (80%), whereas the positive rate was only 50% (3/6) for the immunofluorescent staining of primary cultures of porcine kidney cells inoculated with the specimens. The advantages of the RPHA method are simplicity, high sensitivity, and rapid to do.  相似文献   
993.
The internal transcribed spacer (ITS) regions of rDNA have been routinely employed for identification and phylogenetic analysis of many nematode species. In this study, the intra‐ and interspecies ITS genetic diversity of Bursaphelenchus xylophilus and Bursaphelenchus mucronatus was evaluated. Ninety‐one isolates of the two nematode species collected from 14 Chinese provinces, Japan and Korea were used for ITS‐PCR and sequencing. An unweighted pair group cluster analysis dendrogram clustered them as two B. mucronatus and one B. xylophilus independent clades. Principal component analysis showed the phylogenetic relationship of the two nematode species more clearly; B. mucronatus isolates were separated into more than four groups, whereas B. xylophilus isolates still clustered into a group. The results of the Mantel test indicated the correlation of genetic distance matrices and geographic distance matrices was significant for both nematode species. The genetic differentiation coefficient (Gst) and gene flow (Nm) of B. mucronatus were 0.341 and 1.091, respectively, suggesting the importance of landscape heterogeneity and considerable obstacles for genetic exchange among B. mucronatus isolates in China. However, Gst and Nm of B. xylophilus were 0.188 and 2.151, respectively, very different compared to B. mucronatus. This could be owing to the short‐term introduction of B. xylophilus into China and a rapid spread through anthropogenic pathways. Our work adds to the understanding of the genetic diversity and genetic relationship of the two pine‐parasitic nematode species, and will aid in controlling them in the future.  相似文献   
994.
The comparative molluscicidal activity of different preparations ofBacillus thuringiensis as Thuricide, SAN 401, SAN 402 and SAN 415, onB. alexandrina snails was studied. The results showed that different preparations ofBac. thuring. have a remarkable molluscicidal activity onB. alexandrina snails. However, the obtained results proved thatBac. thuring. with its preparation SAN 415 was the most effective in killing the snails comparing with the other preparations at the same experimental condition. Prolonged exposure ofB. alexandrina to subletal concentration (250 ppm) of SAN 415 delayed its ovipositary activity. Increasing the dose to 500 ppm resulted in a complete loss of egg production. Comparatively exposure of snail groups to the same doses of Thuricide, SAN 401 and SAN 402 resulted only in decreasing its egg laying capacity. These results proved the high potentially effectiveness ofBac. thuring. in its preparation SAN 415 as a biological control agent forB. alexandrina snails. The wayes by which this biological agent acts on the reproductive system of the snails were discussed.  相似文献   
995.
Three distinct forms of vitellogenin (Vg), 600 kDa VgA and VgB and 400 kDa Vg, were discovered biochemically in estrogen treated female plasma. By sequencing of the three Vg cDNAs, the VgA and VgB were recognized as complete Vgs having all yolk protein (YP) domains, and the 400 kDa Vg was thought to be phosvitinless (Pvl) Vg lacking phosvitin (Pv) domain.  相似文献   
996.
Face perception is a skill crucial to primates. In both humans and macaque monkeys, functional magnetic resonance imaging (fMRI) reveals a system of cortical regions that show increased blood flow when the subject views images of faces, compared with images of objects. However, the stimulus selectivity of single neurons within these fMRI-identified regions has not been studied. We used fMRI to identify and target the largest face-selective region in two macaques for single-unit recording. Almost all (97%) of the visually responsive neurons in this region were strongly face selective, indicating that a dedicated cortical area exists to support face processing in the macaque.  相似文献   
997.
998.
999.
1. An experiment was conducted to determine the individual and combined effects of two essential oils, oregano and garlic, on carcass characteristics, meat composition, colour, pH and sensory quality of broiler meat.

2. The diets were supplemented with no essential oil (control), oregano essential oil or garlic essential oil at 300 mg/kg and oregano essential oil at 150 mg/kg + garlic essential oil at 150 mg/kg.

3. Dietary oregano and garlic oil supplementation did not affect carcass yields, the relative weight of carcass parts, breast and thigh meat composition, pH or b* value of breast meat. Oregano + garlic oil supplementation significantly decreased the L* value. The a* value of breast meat in birds given a diet supplemented with oregano oil was lower than that in birds given a diet supplemented with garlic oil and oregano oil + garlic oil. The essential oil addition had no positive effect on the oxidative stability. There was no difference between the treatments in breast appearance.

4. The juiciness, flavour, oxidised flavour and acceptability of breast meat samples were affected by treatments.  相似文献   

1000.
Changes in ascorbate content in primary cultured rat hepatocytes exposed to oxidative stress derived from water soluble radical initiator 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) were examined. Cells were exposed to 0.05 and 5 mg/ml of AAPH as 'mild' and severe' oxidative stresses, respectively. Lipid peroxidation in hepatocytes was induced by 'severe' oxidative stress, but not by 'mild' oxidative stress. Ascorbate decreased at 6 hr after administration of both mild' and severe' oxidative stresses, and recovered to the control level after a further 6 hr. In cells treated with 'severe oxidative stress, however, total ascorbate (reduced form plus oxidized form) had increased 24 hr after administration. These results indicated that consumption alone did not account for the increase of ascorbate in hepatocytes under oxidative stress.  相似文献   
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