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排序方式: 共有310条查询结果,搜索用时 15 毫秒
91.
Ohtsuka H Mukai M Tanami E Tokita M Hashiba Y Kohiruimaki M Shibano K Miura K Morris S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(11):1477-1479
Neonatal Japanese Black (JB) calves show a high incidence of diarrhea. The objective of this study was to analyze the immune cell populations of neonatal JB calves in detail and examine its correlation with the incidence of diarrhea immediately after birth. Understanding the immune cell populations is helpful in clinics in order to determine the condition of the immune system for prevention of diseases. Blood samples were obtained from JB calves on the day of birth. The peripheral leukocyte populations were analyzed separately for calves that had diarrhea within 2 weeks after birth (diarrhea group; n = 26) and for calves without diarrhea (control group; n = 74). The numbers of the peripheral blood CD3(+)TcR1-N12(+) and CD8(+) T cells were significantly lower in the diarrhea group compared with the control group. These findings suggest that the congenital lower peripheral γδ and CD8(+) T cells results in a high risk of diarrhea in neonatal JB calves. 相似文献
92.
Motta RO Cunha LM Leite RC da Silva IJ Pinto AC Braga EM da Cunha AP de Oliveira PR 《Journal of zoo and wildlife medicine》2011,42(3):399-407
This study aims to establish the hematological values of Crotalus durissus collilineatus snakes captured in Brazil as well as to verify the effects of hematozoan infection on these snakes. Eighty-three blood samples were drawn from C. d. collilineatus specimens for analysis. The sample set was composed of 30 males and 30 females, recently caught from the wild, and 11 males and 12 females bred in captivity. Blood samples were used to determine red blood cell counts, white blood cell counts, thrombocyte counts, hematocrit values, hemoglobin concentration, and total plasma protein. Blood smears were used to diagnose Hepatozoon spp. infection and to calculate the parasitic load in the sample as well as the percentage of immature red cells. Results obtained for the wild-caught animals, with and without parasites, were compared among themselves and with the values obtained for the captive-bred animals. Hematological values for C. durissus were established. Wild-caught snakes had an infection rate of 38.3%, while no Hepatozoon sp. infection was detected in the captive-bred animals. The snakes which were not infected by the Hepatozoon sp. exhibited average weight, length, and weight-length ratios higher than those of the infected animals. An increase in immature red cells was noted in the Hepatozoon-infected snakes. 相似文献
93.
St Leger JA Righton AL Nilson EM Fascetti AJ Miller MA Tuomi PA Goertz CE Puschner B 《Journal of zoo and wildlife medicine》2011,42(1):98-104
Vitamin A deficiency has rarely been reported in captive or free-ranging wildlife species. Necropsy findings in two captively housed southern sea otters (Enhydra lutris nereis) included irregular thickening of the calvaria characterized by diffuse hyperostoses on the internal surface. One animal also had moderate squamous metaplasia of the seromucinous glands of the nose. There was no measurable retinol in the liver of either sea otter. For comparison, hepatic retinol concentration was determined for 23 deceased free-ranging southern and northern (Enhydra lutris kenyoni) sea otters from California and Alaska. Free-ranging otters were found to have similar hepatic retinol concentrations (316 +/- 245 mg/kg wet weight) regardless of their location and subspecies. All of these values were significantly higher than the levels in the affected animals. Consumption of a diet with very low vitamin A concentrations and noncompliance in daily supplementation are hypothesized as the causes of vitamin A deficiency in these two sea otters. 相似文献
94.
The study purpose was to determine the prognostic significance of weight changes during feline lymphoma treatment. A secondary purpose was to compare weight changes according to baseline body weight, cell type and location. Records of 209 cats treated for lymphoma with chemotherapy from 1995 to 2007 were evaluated. Signalment, cell type, lymphoma location, baseline body weight, weight during treatment, and outcome information were collected. Lymphoma specific survival (LSS) was compared according to baseline weight and weight changes during treatment. Weight change over time was compared according to cell type (small versus large), location (gastrointestinal versus non-gastrointestinal) and baseline weight. Cats with large cell lymphoma that lost ≥ 5% body weight at 1 month had significantly shorter LSS than those that gained or had stable weight (P = 0.004). Percentage weight change over time differed significantly according to baseline weight group. These findings demonstrate the prognostic importance of weight loss in feline large cell lymphoma. 相似文献
95.
Peregrym Mykyta Kabaš Eva Tashev Alexander Dragićević Snežana Pénzesné Kónya Erika Savchenko Mariia 《Water, air, and soil pollution》2020,231(2):1-10
Water, Air, & Soil Pollution - In this study, a new composite membrane has been prepared by means of blending with maifanite (MFS), activated alumina (AA), and poly(vinylidene fluoride) (PVDF)... 相似文献
96.
Guilherme Senna dos Santos Patrícia Aoki Miyasato Erika Mattos Stein Pio Colepicolo Anthony D. Wright Carlos Alberto de Bragana Pereira Miriam Falkenberg Eliana Nakano 《Marine drugs》2022,20(2)
Schistosomiasis has been controlled for more than 40 years with a single drug, praziquantel, and only one molluscicide, niclosamide, raising concern of the possibility of the emergence of resistant strains. However, the molecular targets for both agents are thus far unknown. Consequently, the search for lead compounds from natural sources has been encouraged due to their diverse structure and function. Our search for natural compounds with potential use in schistosomiasis control led to the identification of an algal species, Laurencia dendroidea, whose extracts demonstrated significant activity toward both Schistosoma mansoni parasites and their intermediate host snails Biomphalaria glabrata. In the present study, three seaweed-derived halogenated sesquiterpenes, (−)-elatol, rogiolol, and obtusol are proposed as potential lead compounds for the development of anthelminthic drugs for the treatment of and pesticides for the environmental control of schistosomiasis. The three compounds were screened for their antischistosomal and molluscicidal activities. The screening revealed that rogiolol exhibits significant activity toward the survival of adult worms, and that all three compounds showed activity against S. mansoni cercariae and B. glabrata embryos. Biomonitored fractioning of L. dendroidea extracts indicated elatol as the most active compound toward cercariae larvae and snail embryos. 相似文献
97.
Erika von Winning 《Journal of pest science》1933,9(4):55-56
Ohne Zusammenfassung
Mit 3 Abbildungen. 相似文献
98.
Isolation and characterization of nine bacteriophages that lyse O149 enterotoxigenic Escherichia coli 总被引:2,自引:0,他引:2
Jamalludeen N Johnson RP Friendship R Kropinski AM Lingohr EJ Gyles CL 《Veterinary microbiology》2007,124(1-2):47-57
The goal of this study was to isolate and characterize phages that might be used in prevention and treatment of porcine post-weaning diarrhea due to O149 enterotoxigenic E. coli (ETEC). Serotype O149:H10:F4 was especially targeted because this is the dominant ETEC serotype. Mixtures of 10 strains of O149:H10:F4 ETEC and of 10 O149:H43:F4 ETEC were used as hosts for isolation of phages in sewage from 38 Ontario pig farms. Six phages (GJ1-GJ6) that lysed O149:H10:F4 ETEC and three (GJ7-GJ9) that lysed O149:H43:F4 ETEC were isolated. All phages produced large, clear plaques. All nine phages had necks and contractile tails and therefore belonged to the Myoviridae. Their estimated genome sizes were 48.3-50.7kb and their restriction enzyme fragments suggested that they were closely related. Phages GJ1-GJ6 lysed 99-100% of 85 O149:H10:F4 ETEC, 0-12% of 42 O149:H43:F4 ETEC, 3-35% of 37 non-O149 porcine ETEC, and 6-68% of the 72 strains of the ECOR collection. Phages GJ7-GJ9 lysed 86-98% of the O149:H43:F4 ETEC, 2-53% of the O149:H10:F4 ETEC, and 24-41% of the non-O149 porcine ETEC. Titres of the nine phages were unaffected by exposure for 16h to pH 5-9. Among phages GJ1-GJ6, resistance of O149:H10:F4 ETEC to one phage was generally not accompanied by resistance to other phages. It is concluded that the nine phages are suitable candidates for prophylaxis and therapy of porcine post-weaning diarrhea due to O149 ETEC. 相似文献
99.
Campylobacter (C.) jejuni and C. coli can cause gastrointestinal disorders in humans characterized by acute inflammation. Inflammatory signals are initiated during interaction between these pathogens and human intestinal cells, but nothing is known about the stimulation of avian intestinal cells by Campylobacter. Interleukin-8 (IL-8) as a proinflammatory chemokine plays an important role in mobilizing cellular defence mechanism. IL-8 mRNA expression in both human intestinal cells (INT 407) and primary intestinal chick cells (PIC) was determined by quantitative real-time RT-PCR. The secretion of IL-8 protein by INT407 was measured using ELISA. Although C. jejuni and C. coli are considered to be harmless commensals in the gut of birds, the avian Campylobacter isolates investigated were able to induce the proinflammatory IL-8 in PIC as well as in INT407. In an in vitro system, C. jejuni as well as C. coli were able to induce IL-8 mRNA in PIC. Relation between the virulence properties like toxin production, the ability to invade and to survive in Caco-2 cells and the level of IL-8 mRNA produced by INT 407 and PIC after infection with Campylobacter strains was also investigated. 相似文献
100.
Gene flow among populations in different selective environments should favor the evolution of phenotypic plasticity over local adaptation. Plasticity in development is a common response to long‐term hypoxia in some widespread African fishes, including Pseudocrenilabrus multicolor, a cichlid that exploits both normoxic (high oxygen) rivers/lakes and hypoxic (low oxygen) swamps. Previous studies have shown that fish from normoxic and hypoxic sites differ in many traits, including gill size, brain size and body shape, and that much of this variation reflects developmental plasticity. However, these earlier studies focused on areas in Uganda where gene flow between swamp and river or lake populations is high. In this study we tested the hypothesis that P. multicolor from a relatively isolated lake population (Lake Saka, Uganda) exhibit low levels of plasticity in traits related to oxygen uptake. Multiple broods of P. multicolor from Lake Saka were reared under low and high dissolved oxygen, and traits related to gill size, brain mass and body shape were quantified. Surprisingly, both gill size and brain mass showed high levels of developmental plasticity. We suggest that high levels of plasticity, particularly in the gill size of P. multicolor, reflects low costs of maintaining the plastic response, even in relatively isolated populations. 相似文献