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排序方式: 共有195条查询结果,搜索用时 15 毫秒
81.
J.C. Pacheco D.W. Kerstetter F.H. Hazin Humberto Hazin R.S.S.L. Segundo J.E. Graves F. Carvalho P.E. Travassos 《Fisheries Research》2011,107(1-3):39-45
Catch composition, catch rates, hooking location, and status at release at haulback were monitored during 81 experimental sets (launches and hauling fishing per day) in a commercial pelagic longline fishery targeting tuna in the equatorial South Atlantic Ocean. Circle hooks (size 18/0, 0° offset) and J-style hooks (size 9/0, 10° offset) with squid baits were deployed in an alternating fashion. The catch composition was not significantly different for most species between the two types of hooks, except for bigeye tuna, which showed a significantly higher proportion of catches on the circle hook (p ? 0.001) and for sailfish, pelagic stingray, and leatherback sea turtle, which had higher catch rates on the J-style hook (p = 0.018, p ? 0.001, and p = 0.044, respectively). Bigeye and yellowfin tuna showed significantly higher rates of survival at the time of gear retrieval with circle hooks, and circle hooks hooked bigeye tuna, yellowfin tuna, swordfish, and sailfish significantly more often externally than internally. Our results suggest that the use of size 18/0, 0° offset circle hooks in the equatorial pelagic longline fishery may increase the survival of bycatch species at the time of gear retrieval with minimal effects on the catches of target species. 相似文献
82.
83.
Tomatoes, lettuce and cucumbers, grown in beds of peat, received 3 levels of copper sulphate (0, 0.5 and 5 g/m2) in factorial combination with 2 rates of liming (average pH values 6.5 and 6.9). Omission of copper resulted in copper deficiency and decreased the yield of tomatoes, lettuce and cucumbers by 11% (P < 0.01), 53% (P < 0.001) and 48% (P < 0.001), respectively. In addition, this deficiency increased the proportion of unmarketable lettuce six-fold (P < 0.001) and that of poorly developed cucumbers by 67% (P < 0.05), but had no effect on the proportion of unevenly ripened tomatoes. Heavy liming (pH 6.9) reduced the yield of lettuce (14%; P < 0.01), but had no effect on quality throughout the trial. Although lettuce and cucumber leaves from the intermediate copper treatment contained only 2 μg/g Cu, the yield and quality of the produce were only slightly, and not significantly, inferior to those obtained at an adequate level of copper (> 7 μg/g). 相似文献
84.
85.
The suppressive effects of three different low dosages of dexamethasone (5, 10 and 15 micrograms kg-1) on serum cortisol concentrations were evaluated in 10 normal cats. On four different days, serum was collected before and at two, four, six and eight hours after the intravenous administration of saline or dexamethasone. Following the administration of saline, no significant difference in mean serum cortisol concentrations was noted between the basal or postinjection values. In contrast, mean serum cortisol concentrations decreased significantly (P less than 0.05) by two hours and remained significantly below mean basal values eight hours after injection of all three dosages of dexamethasone. The degree of cortisol suppression became progressively greater as the dosages of dexamethasone were increased. After administration of the highest dose of dexamethasone (15 micrograms kg-1), serum cortisol decreased to below 5 ng ml-1 by two to four hours and remained suppressed (under 5 ng ml-1) eight hours after injection in all cats. In contrast, two of the 10 cats showed a slight escape from cortisol suppression by eight hours after injection of dexamethasone at the dosage of 10 micrograms kg-1, whereas a dosage of 5 micrograms kg-1 failed to suppress cortisol concentrations below 10 ng ml-1 at any of the sampling times in one cat and was associated with increasing serum cortisol concentrations at eight hours after injection in three cats.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
86.
Thomas K. Graves William D. Schall Kent Refsal Raymond F. Nachreiner 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):287-289
We measured plasma concentrations of Cortisol and aldosterone before and after administration of adrenocorticotropin (ACTH) in dogs with trichuriasis. These dogs had physical examination, historical, and serum electrolyte findings suggestive of hypoadrenocorticism; trichuriasisassociated pseudohypoadrenocorticism has been reported previously. We found normal basal and ACTH-stimulated plasma Cortisol concentrations. Basal and ACTH-stimulated plasma aldosterone concentrations were normal in 2 dogs and increased in 3 dogs, suggesting that the electrolyte abnormalities seen in this clinical syndrome are not due to aldosterone deficiency. 相似文献
87.
Influenza viruses in birds of the Atlantic flyway. 总被引:2,自引:0,他引:2
I L Graves 《Avian diseases》1992,36(1):1-10
Isolation of type A influenza viruses from the feces of 5013 birds of 16 species was attempted during a 33-month study (1977-79). Seventy viruses were isolated from the feces of 3403 ring-billed gulls in Baltimore, Md., during 16 months of sampling. Six hemagglutinin (HA) subtypes and seven neuraminidase (NA) subtypes in 15 combinations were found. The H13N6 virus was the only subtype found each year and accounted for 40% of the isolates. The rate of isolation from gulls was 0.26% in the cold months and 3.0% in the warm months. Hemagglutination-inhibition (HI) and elution-inhibition antibody profiles reflected the presence of some but not all of the viruses isolated. In mute swans, the rates of seroconversions were 16% for HA antibody and 14% for NA antibody, whereas the viral isolation rate was 0.4% over a 3-year period. Both the H5 and the N2 subtypes, which were responsible for the lethal chicken outbreaks in 1983 in Pennsylvania, were isolated from gulls in 1978 in association with subtypes not found in the chicken virus. Also, seroconversions for the H5 HA occurred in mute swans in 1978. 相似文献
88.
89.
E van Engelen MW de Groot VNA Breeveld-Dwarkasing ME Everts GC van der Weyden MAM Taverne VPMG Rutten 《Reproduction in domestic animals》2009,44(5):834-841
The final stages of cervical ripening and parturition resemble an inflammatory process. Although the role of cytokines in both spontaneous and experimentally induced parturitions has been described in several small laboratory animals and humans, the involvement of pro‐inflammatory and regulatory cytokines in physiologic parturition in cows has not been determined. In this study, the cytokine expression profiles were assessed in bovine cervical tissue at several stages of pregnancy and at parturition. Serial biopsy samples of the cervix were obtained from 10 cows on day 185 and day 275 of pregnancy (which was on average 5.4 days before parturition) and at parturition. Messenger RNA expression levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10 and tumour necrosis factor (TNF)α were determined using real‐time polymerase chain reaction and the number of neutrophils and eosinophils was estimated by Luna and Sirius Red staining. At parturition, IL‐8 expression had increased 430‐fold (p < 0.001) when compared with that of the day 185 of pregnancy, large numbers of neutrophils had invaded the cervix while eosinophils remained scarce, IL‐1β had increased eightfold (p < 0.05) and IL‐6 had not changed significantly. Additionally, IL‐10 was increased by 10‐fold (p < 0.001) and TNFα decreased by 57% (p < 0.05) when compared with that of the day 185 of pregnancy. The large increase in expression of IL‐8, enabling the influx of neutrophils, is indicative of its important role in the final stage of cervical ripening and at parturition. As previous studies have shown that neutrophils excrete matrix metalloproteinases (MMP), this might contribute to softening of the cervix. In contrast, the only slightly increased levels of IL‐1, steady concentrations of IL‐6 and decreased TNFα, the potential consequences of increased IL‐10 expression, indicate that final cervical of cows in ripening at term parturition is an inflammatory process influenced by regulatory cytokines. 相似文献
90.
Isolation and characterization of polyphenol type-A polymers from cinnamon with insulin-like biological activity 总被引:10,自引:0,他引:10
Anderson RA Broadhurst CL Polansky MM Schmidt WF Khan A Flanagan VP Schoene NW Graves DJ 《Journal of agricultural and food chemistry》2004,52(1):65-70
The causes and control of type 2 diabetes mellitus are not clear, but there is strong evidence that dietary factors are involved in its regulation and prevention. We have shown that extracts from cinnamon enhance the activity of insulin. The objective of this study was to isolate and characterize insulin-enhancing complexes from cinnamon that may be involved in the alleviation or possible prevention and control of glucose intolerance and diabetes. Water-soluble polyphenol polymers from cinnamon that increase insulin-dependent in vitro glucose metabolism roughly 20-fold and display antioxidant activity were isolated and characterized by nuclear magnetic resonance and mass spectroscopy. The polymers were composed of monomeric units with a molecular mass of 288. Two trimers with a molecular mass of 864 and a tetramer with a mass of 1152 were isolated. Their protonated molecular masses indicated that they are A type doubly linked procyanidin oligomers of the catechins and/or epicatechins. These polyphenolic polymers found in cinnamon may function as antioxidants, potentiate insulin action, and may be beneficial in the control of glucose intolerance and diabetes. 相似文献