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31.
M. Sternlicht S. Goldenberg Brenda F. Nesbitt D. R. Hall R. Lester 《Phytoparasitica》1978,6(3):101-113
The synthetic female sex pheromone ofPrays citri, (Z)-7-tetradecenal, proved to be highly attractive to male moths in the field when released from a variety of dispensers in five different designs of sticky trap. When the pheromone was released from impregnated polyethylene vials, a wide range of initial loadings from 10 μg to 20 mg was attractive, and loadings of 40 μg and above were more attractive than a virgin female moth. Initial loadings of 0.5 mg and 1.0 mg remained attractive for at least five months in the field. Release rates of pheromone from the polyethylene vials under constant laboratory conditions were measured for two different initial loadings. Other isomers of the pheromone and a pheromone ‘mimic’, (Z)-5-dodecenyl formate, were unattractive to male moths and did not affect the attractiveness of the synthetic pheromone or of a virgin female moth. 相似文献
32.
Hall JA Wander RC Gradin JL Du SH Jewell DE 《American journal of veterinary research》1999,60(3):319-327
OBJECTIVE: To determine effect of diets with variable n-6-to-n-3 fatty acid (FA) ratio on CD4+ and CD8+ T-lymphocyte subpopulations, and on results of routine laboratory analyses (CBC and total WBC count, serum biochemical analyses, and urinalysis). ANIMALS: 20 healthy, aged (9.5 to 11.5 years old) female Beagles. PROCEDURE: Dogs were fed 1 of 3 diets that contained 6% fat by weight but differed in amounts of n-6 and n-3 FA. For 11 weeks, 6 dogs were fed a low concentration of n-3 FA (ratio, 31:1), 7 were fed a medium concentration (5.4:1), and 7 were fed a high concentration (1.4:1). Preprandial blood and urine samples were collected before beginning the study and at 8 weeks for evaluation of laboratory variables. Before and at 3, 6, and 8 weeks during the study, blood was drawn for total WBC and lymphocyte counts and for characterization of T-cell subpopulations. At 8 and 10 weeks, dogs were vaccinated with keyhole limpet hemocyanin suspension. Blood was drawn 4 days after each vaccination, and lymphocytes were isolated for flow cytometry. Effects of diet and vaccination on each variable were determined. RESULTS: After vaccination, total lymphocyte count increased and CD4+ T lymphocyte count and the CD4(+)-to-CD8+ ratio decreased in dogs consuming the diet with n-6-to-n-3 FA ratio of 1.4:1. CONCLUSION: Feeding a diet with n-6-to-n-3 FA ratio of 1.4:1 had significant effects on CD4+ T lymphocytes in healthy, aged Beagles after vaccination. 相似文献
33.
Acetolactate synthase (ALS) from one susceptible and two chlorsulfuronresistant biotypes of Stellaria media(L.) Vill. was assayed in the presence of eight known ALS inhibitors. As expected, ALS from the chlorsulfuronresistant biotypes (R1 and R2) showed reduced sensitivity to chlorsulfuron and other sulfonylurea herbicides. The patterns of cross-resistance varied, however, indicating that the alteration in ALS that confers chlorsulfuron resistance does not confer the same level of resistance to other sulfonylurea herbicides. The resistant biotypes were highly cross-resistant to sulfometuron-methyl and DPX-A7H81, but less cross-resistant to triasulfuron. Both R1 and R2 were highly cross-resistant to DTPS (N-[2,6-dichlorophenyl]-5,7-dimethyl-1,2,4-iriazolo[1,5a]pyrimidine-2-siilfoiiamide), but only slightly cross-resistant to imazamethahenz, an imidazolinone herbicide. The differences in the patterns of cross-resistance observed presumably reflect differences in the binding affinity of the herbicides for the altered ALS. The data presented suggest, but do not confirm, that R1 and R2 contain the same ALS mutation. 相似文献
34.
The properties of the major H+-pumps in higher plant cells are described: these are the H+-ATPase of the plasma membrane and the H+-ATPase and the H+-pyrophosphatase of the tonoplast. They are distinguished by their structure, mechanism of action, kinetic properties, and location within the cell. The uses and value of isolated and purified membrane vesicles in transport studies are discussed. A particular example is given by the use of plasma membrane vesicles, purified by phase partition, to study proton/ sucrose co-transport in Ricinus cotyledons. Current evidence for the interference with these pumps by growth regulators, toxins and xenobiotics is outlined. 相似文献
35.
Effects of dietary change and rotavirus infection on small intestinal structure and function in gnotobiotic piglets 总被引:1,自引:0,他引:1
G A Hall K R Parsons G L Waxler K J Bunch R M Batt 《Research in veterinary science》1989,47(2):219-224
The combined effects of weaning and rotavirus infection on small intestinal structure and function and on growth rate were studied in 28 gnotobiotic piglets. There was little damage by rotavirus to the proximal small intestine, some damage to the mid small intestine and relatively severe damage to the distal small intestine; villi were stunted, crypts lengthened and activities of all brush border enzymes decreased. The damage was short-lived despite the synchronisation of rotavirus infection with simulated weaning. There was no evidence of persistent damage to the small intestine and growth rate was unaffected. 相似文献
36.
Seventeen paragangliomas were identified in a retrospective review of 200 NTP/NCI carcinogenicity studies in F344/N rats that served either as control or treated animals. Most tumors were grossly visible and located in the retroperitoneum adjacent to the vertebrae and aorta near the kidneys. Three microscopically detected paragangliomas were found at the base of the heart. Microscopically, neoplastic cells were in nests separated by reticulin fibers and capillaries. Argyrophil granules were in the cytoplasm of the retroperitoneal and mediastinal paravertebral tumors. Dense granules were found in the one tumor examined ultrastructurally. Some tumors had areas of necrosis and tumor emboli were present in the lumen of the abdominal aorta and vena cava adjacent to the tumor with metastases present in pulmonary vessels. The incidence of retroperitoneal neoplasms was 3 times more frequent in male than in female F344/N rats. 相似文献
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S A Hall 《The Veterinary record》1965,77(42):1237-1241