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911.
NA Geverink A Kappers JA van de Burgwal E Lambooij HJ Blokhuis VM Wiegant 《Canadian Metallurgical Quarterly》1998,76(8):2080-2085
The effects of regular moving and handling during the finishing period on behavioral and physiological responses of pigs during preslaughter treatment and consequences for meat quality were studied. From the age of 10 wk onward, 144 pigs were housed in groups of four (two gilts and two castrates) and subjected to one of the following treatments. The Environment treatment allowed pigs to move freely for 8 min outside their home pen. Then the pigs were transported in a box for 2 min, and after which they were returned to their home pen. In the Handling treatment, an experimenter remained for 3 min in the pen, and whenever a pig made contact, it was gently stroked. The experimenter then walked for an additional 1 min, without attempting to pat or stroke any pigs but subsequently held each pig in a tight grip for about 5 s. This entire procedure was then repeated. A Control treatment was also included, in which the pigs were subjected to no treatment. The Environment and Handling treatments were applied twice a week at the age of 15, 17, 19, 21, and 23 wk. At 25 wk of age, pigs were transported to the abattoir. They were held unmixed in the truck and in lairage and were manually stunned. The stockmen needed significantly less time to move Environment pigs out of their pen and into the transport box. There were no differences between treatments in salivary cortisol concentrations before or after transport. Environment and Handling pigs had paler meat than Control pigs. Glycogen content at 1 h after death and water-holding capacity were lower in Environment pigs than in Control pigs, but this did not lead to a higher incidence of PSE meat. We conclude that the pigs that had experience with leaving their home pen and some of the transport conditions were much easier to handle at loading. Pigs that are easier to move are less likely to be subjected to rough handling, which implies improved welfare, and the workload for personnel at the time of marketing is reduced. Differences in meat quality due to treatment were slight. 相似文献
912.
913.
914.
B Buzadzi? D Blagojevi? B Kora? ZS Saici? MB Spasi? VM Petrovi? 《Canadian Metallurgical Quarterly》1998,17(3-4):271-276
The aim of this work was to determine the activity of the antioxidant enzymes: superoxide dismutase (EC 1.15.1.1; SOD), catalase (EC 1.11.1.6; CAT), glutathione peroxidase (EC 1.11.1.9; GSH-Px), glutathione-S-transferase (EC 2.5.1.18; GST), glutathione reductase (EC 1.6.4.2; GR) and the low molecular mass antioxidants: ascorbic acid (ASA) and vitamin E (vit E) in the kidney of ground squirrels during circannual changes. Keeping the ground squirrel at the temperature of thermic neutrality (30 degrees C) provides a stable euthermic state during the whole year and thus any change is due to the circannual rhythm. The highest specific activity of all examined antioxidative defense enzymes in the kidney was found in the spring, when ground squirrels are seasonally the most active. In the summer, lower specific activity of GSH-Px as well as of SOD and CAT were noted and, when expressed per g wet mass, only a decrease in GSH-Px activity was recorded. In the kidney of ground squirrels kept at 30 degrees C, the lowest specific activity of all examined enzymes was found during the winter and, when expressed per g wet mass, only the SOD activity was lower than in the spring and summer. Higher amounts of vitamins C and E were found in the ground squirrel kidneys in the summer. The results obtained in this work demonstrate that circannual regulation of metabolic activity, which is inherent to seasonal hibernators, is also expressed at the level of antioxidative defense in the kidneys. 相似文献
915.
C Shibata BM Balsiger WJ Anding JA Duenes VM Miller MG Sarr 《Canadian Metallurgical Quarterly》1998,43(11):2446-2454
This experiment was designed to determine mechanisms of change in nonadrenergic, noncholinergic (NANC) inhibitory neurons in the ileum after small bowel transplantation (SBT) in the rat and whether nitric oxide (NO) serves as an important NANC inhibitory neurotransmitter in the rat ileum. Eight groups of rats (N > or =8 rats/group) were studied: neurally intact unoperated controls; rats one week after anesthesia and sham celiotomy; and separate groups one and eight weeks after either 40 min of cold ischemia of the jejunoileum, combined jejunal and ileal intestinal transection/reanastomosis, or orthotopic SBT of the entire jejunoileum. Contractile activity was evaluated in full-thickness ileal circular muscle strips under isometric conditions. Spontaneous activity did not differ among groups. In all groups, exogenous NO, NG-monomethyl-L-arginine (L-NMMA, an NO synthase inhibitor), and methylene blue (soluble guanylate cyclase inhibitor) had no effect on spontaneous activity, while 8-bromocyclic guanosine monophosphate (8Br-cGMP) inhibited contractile activity in all groups. Low frequency (2-10 Hz) electrical field stimulation (EFS) inhibited contractile activity only in control and SBT groups; L-NMMA and methylene blue did not alter the response to EFS in any group. These results suggest that each aspect of the SBT procedure, ischemia/reperfusion injury, disruption of enteric neural continuity by intestinal transection, and extrinsic denervation, alter function of enteric ileal inhibitory neurons separately early (one week) after operation. NO, a known inhibitory neurotransmitter in other gut regions, does not affect ileal circular muscle in neurally intact tissue nor mediate functional changes in inhibitory nerve function nor smooth muscle contractility after SBT. 相似文献
916.
The authors claim that unlike most other studies, in which the variability of productivity data was shown to fall within a specific distributional shape, this work has brought into light a distribution which is flexible and yet represents in a simple form most productivity distributions. This was shown in the contrasting distributional shapes of concreting and excavation productivity distributions. 相似文献
917.
AV Potashov VP Morozov VM Savranski? IP Kudrevatykh ES Did-Zurabova AV Kimkov 《Canadian Metallurgical Quarterly》1998,(7):4-6
Clinical and pathogenetic findings on 147 patients with duodenal ulcer (DU) and 29 patients with DU complicated by ulcerogenic bleeding were compared. This allowed to single out significant criteria for prediction of development of bleeding in such patients: male sex freguent seasonal exacerbations, hereditary load, location of the ulcer at the back wall of the duodenal bulb, negative atropine test, HLA-phenotype B35, A2 A3, A2 AX. High acidity and large sixe of DU were hot prognostically independent. The importance of complex approach in solution of prognostic problems is emphasized. 相似文献
918.
The transition to multicellularity is a key feature of the Dictyostelium life cycle, and two genes, gbf and lagC, are known to play pivotal roles in regulating this developmental switch. lagC-null and gbf-null cells fail to induce cell-type-specific genes ordinarily expressed during multicellular development. The null mutants also share a similar morphological phenotype: mutant cells repeatedly aggregate to form a loose mound, disperse, and reform a mound, rather than proceeding to form a tip. To characterize defects in morphogenesis in these mutants, we examined cell motion in the mutant mounds. In analogy with the failed transition in gene expression, we found that lagC-null and gbf-null mounds failed to make a morphogenetic transition from random to rotational motion normally observed in the parent strain. One reason for this was the inability of the mutant mounds to establish a single, dominant signaling-wave center. This defect of lagC-null or gbf-null cells could be overcome by the addition of adenosine, which alters cAMP signaling, but then even in the presence of apparently normal signaling waves, cell motility was still aberrant. This motility defect, as well as the signaling-wave defect, could be overcome in lagC-null cells by overexpression of GBF, suggesting that lagC is dispensable if GBF protein levels are high enough. This set of morphogenetic defects that we have observed helps define key steps in mound morphogenesis. These include the establishment of a dominant signaling-wave center and the capacity of cells to move directionally within the cell mass in response to guidance cues. 相似文献
919.
VM Pisareva 《Canadian Metallurgical Quarterly》1998,94(4):42-43
The method of soya protein extraction from sausage products was developed for soya protein content determination by isoelectric focusing. It was showed most optimal extraction agent was 3% solution of Triton X100. 相似文献
920.
JC Von Frijtag G Croiset WH Gispen RA Adan VM Wiegant 《Canadian Metallurgical Quarterly》1998,123(8):1503-1508
1. In accord with previous studies intracerebroventricular (i.c.v.) injections of ACTH1-24 (1 microg) induced a display of excessive grooming, and increased the plasma concentrations of ACTH and corticosterone. Pituitary-adrenal activation was blocked by pretreatment with dexamethasone, indicating that the effect of the (i.c.v.) injected peptide was not caused by a peripheral effect on the adrenal cortex. 2. Doses of 1 and 3 microg of a non-selective melanocortin-3/4-receptor antagonist (SHU 9119), or of 5 and 10 microg of a selective melanocortin-4-receptor antagonist ([D-Arg8]ACTH4-10), coadministered (i.c.v.) with 1 microg ACTH1-24, inhibited the ACTH1-24-induced activation of the hypothalamus-pituitary-adrenal-axis and excessive grooming. 3. In addition, several doses of the selective melanocortin-3-receptor agonist Lys-gamma2-MSH were centrally administered, but neither neuroendocrine, nor excessive grooming responses were observed. 4. These results imply that the melanocortin-4-receptor, and not the melanocortin-3-receptor, is involved in the ACTH1-24-induced rise in plasma levels of ACTH and corticosterone, and excessive grooming. 相似文献