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排序方式: 共有241条查询结果,搜索用时 31 毫秒
1.
L F Woodard H W Renshaw D Burger C S McCain R B Wilson 《American journal of veterinary research》1979,40(5):636-644
2.
Transmissible mink encephalopathy (TME) virus retained biological activity after prolonged storage in formalin (about three and a half years) and in paraffin tissue blocks used for histologic preparations (about six and a half years). Thus, TME tissues in formalin and in paraffin blocks should be handled as contaminated materials. 相似文献
3.
DB ADAMS JJ LYNCH† BH ANDERSON LR FELL‡ GN HINCH§ RK MUNRO¶ 《Australian veterinary journal》1990,67(12):443-445
Three-year-old, non-lactating and non-pregnant Merino ewes, raised on pasture under a program of strategic treatment with anthelmintic and found to be extremely resistant to "trickle" infection with Haemonchus contortus, were given single-dose infections with either H. contortus or Trichostrongylus colubriformis or both species together. The purpose was to ascertain the intensity of protective immunity against the 2 parasites in sheep with immunity acquired from a presumably slight exposure to infection. To provide a criterion, some infected ewes were immunosuppressed with corticosteroid, dexamethasone. Untreated ewes were extremely resistant to challenge infection with either 15,000 or 150,000 H. contortus or 15,000 T. colubriformis. Surprisingly, when mixed infection was given, egg counts for H. contortus were significantly elevated compared with infection by that species alone. Antibody to antigens from infective larval and adult H. contortus was measured in serum by enzyme-linked-immunosorbent assay (ELISA) during the course of infection. Serum titres against larval antigens were significantly depressed when infections with either H. contortus or T. colubriformis were permitted by immunosuppression with dexamethasone, whereas those against adult antigen were depressed when infection with T. colubriformis was permitted. 相似文献
4.
Y. Burger N. Katzir G. Tzuri V. Portnoy U. Saar S. Shriber R. Perl-Treves R. Cohen † 《Plant pathology》2003,52(2):204-211
Screening of genotypes of melon ( Cucumis melo ) for resistance to wilt caused by Fusarium oxysporum f.sp. melonis is often characterized by wide variability in their responses to inoculation, even under carefully controlled conditions. The variability at the seedling stage of 17 genotypes susceptible to race 1 was examined in growth-chamber experiments. Disease incidence varied from 0 to 100% in a genotype-dependent manner. Using four combinations of light (60 and 90 µ E m−2 s−1 ) and temperatures of (27 and 31°C), only light intensity showed a statistically significant effect. Marker-assisted selection for fusarium resistance breeding using cleaved amplified polymorphic sequence (CAPS) and sequence-characterized amplified region (SCAR) markers were compared using a single set of genotypes that included 24 melon accessions and breeding lines whose genotype regarding the Fom-2 gene was well characterized. The practical value of the markers for discriminating a range of genotypes and clarifying the scoring of phenotypes was also tested using a segregating breeding population which showed codominant SCAR markers to be useful in marker-assisted selection. 相似文献
5.
6.
笔者在临床上曾遇到一疑似“碘酊”致牛死亡的病例,由于未曾见过碘酊致牛死亡的报道,查阅资料也终未得到答案.笔者将其整理如下,供同行探讨。 相似文献
7.
8.
L S Sammons R H Kenyon G T Burger W R Beisel C E Pedersen 《American journal of veterinary research》1977,38(6):907-910
Acid-base alterations and changes in other selected serum constituents (free fatty acids, triglycerides, cholesterol, copper, cortisol, alpha1-acid glycoprotein, haptoglobin, and albumin) were measured during a study of Rocky Mountain spotted fever in 16 male rhesus macaques. Blood samples were taken from nonanesthetized macaques conditioned to repeated handling. Arterial pH increased and PCO2 decreased during the febrile period. Free fatty acids, triglycerides, copper, cortisol, alpha1-acid glycoprotein, and haptoglobin increased, whereas albumin decreased during the disease. Significant changes were not observed in arterial PO2. Cholesterol remained unchanged. The increase in arterial pH and decrease in PaCO2 indicated that respiratory alkalosis was present in macaques acutely affected with Rocky Mountain spotted fever. 相似文献
9.
本文阐述了猪链球菌病的临床症状、实验室检验及防治方法,力求为科学防控猪链球菌病提供有益的探索和参考。 相似文献
10.
Brian S. Dorr Loren W. Burger Scott C. Barras Kristina Casscles Godwin 《Journal of the World Aquaculture Society》2012,43(4):502-513
The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish‐eating birds, with the Double‐crested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November–April) 2000–2001 and 2003–2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred from 1 January to 31 March. Losses in terms of biomass, number, and dollar value were greater for foodfish ponds than fingerling ponds. Monthly weighted estimates of catfish consumed were 1775.3 and 1346.6 m.t. over winters 2000–2001 and 2003–2004, respectively. Total estimated losses for foodfish and fingerling ponds in 2000–2001 were $11.56 and $0.48 million, respectively, and in 2003–2004 were $5.22 and $0.40 million, respectively. Maximum dollar loss occurred during March in 2000–2001 and during February in 2003–2004. In this study, the volatility in variable production costs and nominal sales price, and distribution of cormorants on pond types and regionally were key factors in resulting economic loss estimates. 相似文献