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991.
992.
An integrated broiler company experienced a major outbreak of pullorum disease during 1990. The outbreak resulted in the distribution of Salmonella pullorum-infected birds to more than 150 roaster flocks in five states. Twenty-two parent (multiplier) breeder flocks became infected. An epizootiological investigation uncovered a grandparent male line breeder flock as the index flock supplying males to the affected parent flocks. Transmission apparently occurred vertically through the egg and horizontally by contact in the hatcheries and by placement of chicks on contaminated litter. 相似文献
993.
Structural factors governing the redistribution of triforine, chloraniformethan and related compounds on barley and marrow leaves have been investigated. Replacing the 3,4-dichloroanilino or piperazino groups gave compounds which in general underwent acropetal movement, and the degree of redistribution was greatest with the more hydrophilic compounds. Replacing the trichloromethyl by other halogenomethyl groups, or replacing the formyl by other keto groups, gave compounds which were not redistributed. No significant redistribution of any compound in the vapour phase was observed. 相似文献
994.
David Ruslander Antony S. Moore BVSc MVSc John M. Gliatto Deborah L'Heureux Susan M. Cotter 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):299-301
Cytosine arabinoside (AraC) was administered as a continuous IV infusion to 15 dogs with malignant lymphoma at a dose of 300 mg/m2 /d for 2 consecutive days. Dogs were re-examined 7 d after treatment for response to therapy and for hematologic toxicity. Regardless of response, all dogs were started on combination chemotherapy at this time. Other toxicities were reported by owners. No dog responded objectively to Ara-C treatment, although 1 dog with circulating lymphoblasts had partial regression of lymphadenopathy but persistent blastemia. Thrombocytopenia (platelet count < 200,000/μL) 7 days posttreatment was the most commonly encountered hematologic toxicity, occurring in 10 of 14 dogs. Three of these 10 dogs were also mildly neutropenic (neutrophil counts of 2000 to 3000 cell/μL). Nonhematologic toxicity occurred in 8 of 15 dogs and was principally gastrointestinal in nature and mild in severity. Cytosine arabinoside at a dose of 300 mg/m2 /day was not considered an active drug for the induction of remission in dogs with lymphoma. 相似文献
995.
Australian red claw crayfish Cherax quadricarinatus were cultured in nine 0.02-ha earthen ponds at densities of l/m2 , 3/m2 and 5/m2 for 158 d. Average weight at stocking was 3.2 g. All ponds were provided with a combination of hay and corn silage at a rate of 500 kg/ha per month and a commercial crayfish ration fed at 5%, decreasing to 2% of estimated biomass/d during the growing season. Overall survival rate was 72%, and did not differ among treatments. Final yields and average weights varied significantly with stocking density. Red claw averaged 67 g with an average pond yield of 475 kg/ha at l/m2 . At 3/m2 and 5/m2 , red claw averaged 48 g and 38 g, respectively, and yielded 1,020 kg/ha and 1,422 kg/ha, respectively. 相似文献
996.
Clive A. Henrick Barbara A. Garcia Gerardus B. Staal David C. Cerf Richard J. Anderson Karen Gill Henry R. Chinn Jeffrey N. Labovitz Michael M. Leippe Sam L. Woo Robert L. Carney Douglas C. Gordon Gustave K. Kohn 《Pest management science》1980,11(2):224-241
A new series of substituted 2-anilino-3-methylbutyrates has been prepared; bioassay data for these compounds on Heliothis virescens, Musca domestica, Aphis fabae and Tetranychus urticae are presented and discussed. Some unexpected relationships were observed between the nature of the substituents and the biological activity. Increases in foliar stability were noted with certain substitution patterns. Both α-cyano-3-phenoxybenzyl 3-methyl-2-(α, α, α,2-tetrafluoro-p-toluidino)butyrate and the corresponding 2-(2-chloro-α, α, α-trifluoro-p-toluidino)-3-methylbutyrate showed good stability in air and light, and exhibited biological activities of a similar nature and potency to those of previously known synthetic pyrethroids. Esters of the (R)-2- anilino-3-methylbutyric acids are far more active than those prepared from the (S)-enantiomers. The (R)-configuration at C-2 in these acids is sterically equivalent to the active absolute configuration at the chiral carbon α to the carboxylate group in both the permethrin and the fenvalerate types of pyrethroids. A new class of insecticidal 2-(isoindolin-2-yl)alkanoates is also reported. In this series the most biologically active analogue was α-cyano-3-phenoxybenzyl 3-methyl-2-(4,5,6,7-tetrafluoroisoindolin-2-yl)butyrate. These esters were considerably less stable than the anilino analogues on exposure to air and light. 相似文献
997.
Larry G. Adams DVM PhD David J. Polzin DVM PhD Carl A. Osborne DVM PhD Timothy D. O''Brien DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):36-40
Urine protein/creatinine (UP/C) ratios and 24-hour urinary protein excretion were compared in clinically normal cats and cats with surgically induced chronic renal failure (CRF). Mean 24-hour urinary protein excretion in 30 clinically normal cats fed a 28% protein diet (dry weight basis) was 4.93 mg/kg/24-hour (SD = 1.34) with a range of 2.99 to 8.88. Mean UP/C ratio in these cats was 0.134 (SD = 0.037) with a range of 0.073 to 0.239. Mean 24-hour urinary protein excretion in CRF cats was 10.49 mg/kg/24-hour (SD = 11.28) with a range of 2.16 to 62.93. Mean UP/C ratio in the CRF cats was 0.359 (SD = 0.374) with a range of 0.061 to 1.916. Linear regression showed high correlation (R2 = 0.973, P less than 0.001) between 24-hour urinary protein excretion and UP/C ratio in clinically normal cats and cats with surgically induced chronic renal failure. The regression equation for 24-hour urinary protein excretion versus UP/C ratio was: 24-hour urinary protein excretion = 29.39 (UP/C) + 0.18. Results of this study indicate that UP/C ratios are a valid estimate of 24-hour urinary protein excretion in clinically normal and CRF cats. Dietary protein intake significantly affected UP/C ratios in clinically normal cats and cats with surgically induced CRF. Therefore, the influence of dietary protein should be considered when interpreting UP/C ratios. 相似文献
998.
Michael Elliott Andrew W. Farnham Norman F. Janes David M. Soderlund 《Pest management science》1978,9(2):112-116
The insecticidal activities to Musca domestica L. and Phaedon cochleariae Fab. of a series of 3-phenoxybenzyl pyrethroid esters with a cyano substituent at the 2-, 6-. (R)-α-, or (S)-α-position are compared with those of the unsubstituted analogues. Only an (S)-α-substituent enhances activity; others diminish or almost eliminate it. (RS)-α-mixtures are generally less active than would be predicted from the potencies of their separate constituents. 相似文献
999.
David C. Griffiths 《Pest management science》1977,8(3):258-263
Results are summarised of tests of seed dressings with synthetic pyrethroids against wheat bulb fly (Delia coarctata) and wireworms (Agriotes spp.). 相似文献
1000.