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排序方式: 共有1347条查询结果,搜索用时 15 毫秒
1.
Holly L. Jordan DVM Carol B. Grindem DVM PhD Edward B. Breitschwerdt DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1993,7(5):261-265
The prevalence of feline thrombocytopenia (<200,000 platelets/L) at North Carolina State University, College of Veterinary Medicine Teaching Hospital, from January 1985 to March 1990, was 1.2% (41/3300). Cats were divided into six categories based on clinical diagnoses: 29% (12/41) had infectious disease, 20% (8/41) had neoplasia, 7% (3/41) had cardiac disease, 2% (1/41) had primary immune-mediated disease, 22% (9/41) had multiple diseases, and 20% (8/41) had disorders of unknown etiology. The mean platelet count for all thrombocytopenic cats was 52,000/μL ± 46,000/μL (1 SD) with a range of 1000–190,000/μL. No significant differences were found between groups with respect to platelet count, packed cell volume, or white blood cell count, though anemia and leukopenia were common among the cats as a whole. Bleeding disorders (hemorrhage or thrombosis) were observed in 29% (12/41) of thrombocytopenic cats and were more likely to be associated with neoplasia, cardiac disease, and platelet counts less than or equal to 30,000/μL. Disseminated intravascular coagulopathy was diagnosed in 12% (5/41) of the cats. Infections and/or neoplasia affecting the bone marrow were the most common diseases associated with thrombocytopenia. Feline leukemia virus and myeloproliferative neoplasia accounted for approximately 44% (18/41) of the specific diagnoses in thrombocytopenic cats. (Journal of Veterinary Internal Medicine 1993; 7:261–265. Copyright © 1993 by the American College of Veterinary Internal Medicine.) 相似文献
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David L. Kaplan Roy Hartenstein Edward F. Neuhauser Michael R. Malecki 《Soil biology & biochemistry》1980,12(4):347-352
Survival and/or growth were used to assess optimum and potentially deleterious physico-chemical conditions in the environment of the earthworm Eisenia foetida. Maximum weight was gained between 20 and 29°C with horse manure or activated sludge as food. Maximum weight gain as a function of moisture in activated sludge occurred between 70 and 85%. All worms died within a week at pH values <5 or >9; optimum pH for gain in weight centered around 7.0 Soluble salts in excess of 0.5% were lethal, though ammonium acetate caused 100% mortality at a concentration of 0.1%; concentrations in manures contaminated by urine or cattle slurry may be lethal, while those present in noncontaminated manure, with an electrolytic conductivity of 1.5–3mmhos, support weight gain. Inorganic chemicals that are commonly used to coagulate sludges, often as a preliminary to land application, were innocuous at concentrations higher than those normally used at wastewater treatment plants. Anaerobically digested sludges are toxic to earthworms, and are characterized by low oxidation-reduction potentials; when placed upon a soil substrate the redox potential increases slowly, and though the sludge tested in this study was nontoxic at Eh values in excess of 250 mV, it provided insufficient nutriment to E. foetida to allow weight gain. With activated sludge as food, growth of E. foetida occurred more rapidly when soil was present, independently of whether it was placed as a substrate beneath the sludge or mixed into the sludge. Growth occurred more rapidly when activated sludge was placed on substrates which allowed drainage, though loam or ashed loam appeared superior to others, such as glass beads or sand; the growth promoting factor is related to the inorganic fraction of the soil. 相似文献
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人们认为猪圆环病毒2型(PCV2)是发生断奶仔猪多系统衰竭综合征的一个必要因素.目前断奶仔猪多系统衰竭综合征在欧洲称作猪圆环病毒病(PCVD),在北美称作猪圆环病毒相关疾病(PCVAD). 相似文献
6.
Diniz PP Maggi RG Schwartz DS Cadenas MB Bradley JM Hegarty B Breitschwerdt EB 《Veterinary research》2007,38(5):697-710
The purpose of this study was to determine the serological and molecular prevalence of Bartonella spp. infection in a sick dog population from Brazil. At the S?o Paulo State University Veterinary Teaching Hospital in Botucatu, 198 consecutive dogs with clinicopathological abnormalities consistent with tick-borne infections were sampled. Antibodies to Bartonella henselae and Bartonella vinsonii subsp. berkhoffii were detected in 2.0% (4/197) and 1.5% (3/197) of the dogs, respectively. Using 16S-23S rRNA intergenic transcribed spacer (ITS) primers, Bartonella DNA was amplified from only 1/198 blood samples. Bartonella seroreactive and/or PCR positive blood samples (n=8) were inoculated into a liquid pre-enrichment growth medium (BAPGM) and subsequently sub-inoculated onto BAPGM/blood-agar plates. PCR targeting the ITS region, pap31 and rpoB genes amplified B. henselae from the blood and/or isolates of the PCR positive dog (ITS: DQ346666; pap31 gene: DQ351240; rpoB: EF196806). B. henselae and B. vinsonii subsp. berkhoffii (pap31: DQ906160; rpoB: EF196805) co-infection was found in one of the B. vinsonii subsp. berkhoffii seroreactive dogs. We conclude that dogs in this study population were infrequently exposed to or infected with a Bartonella species. The B. henselae and B. vinsonii subsp. berkhoffii strains identified in this study are genetically similar to strains isolated from septicemic cats, dogs, coyotes and human beings from other parts of the world. To our knowledge, these isolates provide the first Brazilian DNA sequences from these Bartonella species and the first evidence of Bartonella co-infection in dogs. 相似文献
7.
The organization of two farmer-managed irrigation systems in the western hills of Nepal is described by examining the ways in which the activities of water allocation, water distribution, maintenance, and resource mobilization are performed. Due to the topography and environment, these two organizations are structured primarily to mobilize the large amount of labor required for maintenance of the intake and canal. Both organizations precisely define each member's water allocation. In one system, water is allocated in proportion to the area of an individual's land holding, while in the other water allocation is by purchased shares. These two cases were used to analyze the importance of the principle of water allocation for expansion of area irrigated and equity of access to irrigation. Evidence from the two systems shows that in this hill environment water allocation by purchased shares provides the individual incentive and an organizational mechanism for efficient development of irrigation resources. Expansion of area irrigated and equity of access to irrigation were found to be greater in the system which allocates water by purchased shares than where water was allocated in proportion to area irrigated. 相似文献
8.
Sami Saidi Marie-Pierre Belleville André Deratani Raja Ben Amar 《Journal Of Aquatic Food Product Technology》2013,22(2):251-264
ABSTRACTA protein hydrolysate was prepared from proteins of tuna dark muscle by-product. The hydrolysis conditions (time, temperature, pH, and enzyme concentration) using Alcalase was optimized by response surface methodology (RSM). The regression coefficient close to 1.0, observed during experimental and validation runs, indicated the validity of the model. The hydrolysate produced under the optimum conditions determined by RSM has a low rate of peptide fraction of molecular weight of 4–1 kDa. Meanwhile, the results obtained by hydrolysis under optimal conditions determined by a complementary study (temperature 55°C, time 60 min, 1% enzyme concentration, and pH 8.5) show that the hydrolysate produced has a height rate of the peptide fraction of molecular weight of 4–1 kDa. The amino acid composition of the protein hydrolysate prepared proved to have the potential for application as an ingredient in balanced fish diets and as a source of nitrogen in microbial growth media. 相似文献
9.
Mitochondrial NAD(P)-dependent malic enzyme [EC 1.1.1.39, L-malate: NAD+ oxidoreductase (decarboxylating)] was purified from herring testicular tissue to a specific activity of 26.4 μmol NADH/min/mg
protein. Herring testicular tissue is one of the most abundant sources of this enzyme. The purification procedure involved
differential centrifugation of mitochondria and then chromatography on DEAE-Sephacel, Red Agarose and Sephacryl S-300. This
enzyme catalyzes the oxidative decarboxylation of malate in the presence of Mn2+ and either NAD or NADP. Under Vmax conditions the ratios for the rate of NAD/NADP reduction was 1.8. A study of the reductive carboxulation reaction indicated
that this enzyme reaction is reversible; at pH 7.0 the reverse reaction exhibited 22% of the activity of forward reaction.
Some kinetic characteristics of the enzyme were determined. ATP was found to be a competitive inhibitor with respect to malate.
Fumarate reversed ATP inhibition. Regulation of NAD(P)-dependent malic enzyme from herring testicular tissue mitochondria
could respond to changing levels of mitochondrial ATP and fumarate in vivo. 相似文献
10.
Khemiss F Ahmadi S Massoudi R Ghoul-Mazgar S Safta S Moshtaghie AA Saïdane D 《Fish physiology and biochemistry》2009,35(3):541-549
The everted gut sac technique has been used to investigate the effect of Vibrio vulnificus on water and electrolyte (Na+, K+, Cl−, HCO3
−) transport on the intestine of sea bream (Sparus aurata L.). Both the anterior and the posterior intestine were incubated in a medium containing 108
V. vulnificus cells ml−1 at 25°C for 2 h. The presence of V. vulnificus resulted in a significant reduction (P < 0.05) of water absorption in the anterior intestine, while sodium absorption in the anterior (P < 0.01) and posterior (P < 0.05) intestine was elevated. Chloride absorption was increased, but the changed was not significant, while potassium absorption
decreased significantly (P < 0.05), but only in the posterior intestine. Incubation the sea bream intestine with V. vulnificus did not affect carbonate secretion in the anterior segment, whereas high secretion was stimulated in the posterior segment
(P < 0.01). Histological evaluations demonstrated damage in the anterior intestine of sea bream that was characterized by the
detachment of degenerative enterocytes, alterations in the microvilli, and the presence of a heterogenous cell population,
indicating inflammation. Based on our results, we conclude that V. vulnificus caused cell damage to the intestine of sea bream and that the anterior intestine is more susceptible than the posterior part
of the intestine. Several hypotheses are suggested to explain our observations, such as the presence of higher numbers of
villosities in the anterior intestine than in the posterior one and/or the presence of endogenous bacteria in the posterior
intestine which may have a protector role. 相似文献