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91.
A large number of synthetic derivatives, inorganic compounds or naturally occurring substances are able to depress, regulate or enhance the immune response. Immunomodulators, among which some are chemically well defined and others are complex preparations, exhibit a great variety of chemical structures which are briefly reviewed, without details on their immunopharmacological properties. These molecules allow access to a new type of therapy which aims at acting on the host defense mechanisms.  相似文献   
92.
Development and phenobarbital (PB) induction of microsomal cytochrome P-450, cytochrome P-450 reductase, two epoxidation, and two O-demethylation activities were examined in chronologically timed populations of insecticide-susceptible (NAIDM) and -resistant (Rutgers) house flies. Measurements of these enzymes started with the pharate adult stage and ended 5 days following eclosion. Untreated insects of both strains had comparable reductase levels, whereas cytochrome P-450 and associated monooxygenase activities were 1.5-fold or more higher in Rutgers. Maximum induction, as well as toxicity, occurred at a lower PB concentration in NAIDM than Rutgers. The drug caused consistently higher increases in enzymes and activities within 12 hr of starting treatment in both strains. When PB was withdrawn from treated flies (both strains) 48 hr after treatment began, specific activities (product min?1 mg protein?1) in all enzymes returned to control values in 24 hr while metabolic capacity (product min?1 insect?1) achieved control values within 48 hr. The changes in turnover numbers (pmol product min?1 pmol P-450?1), in conjunction with the differences in the monooxygenation of the four substrates, suggest that PB treatment induced both a quantitative and qualitative change in NAIDM monooxygenation but only a quantitative change in Rutgers monooxygenation.  相似文献   
93.
The following viruses as well as bacteria and mycoplasma have been isolated from dogs with contagious respiratory disease: canine distemper virus; Canine adenoviruses (type 1 and 2); Parainfluenza type 2 (SV5); Reovirus type 1; Canine Herpesvirus; Bordetella bronchiseptica, Streptococcus, Pasteurella, Staphylococcus and Mycoplasma. The occurrence of these agents can be in direct relationship with: the evolution of a systemic disease; respiratory disorders being a regular or inconsistant symptom of this disease; the evolution of a disease restricted to the respiratory tract; the tropism of the bacterial or viral agent is exclusively respiratory; secondary bacterial complications to a primary viral infection; saprophyte state or latency without pathologic significance. These various infectious agents are implicated alone or in mixed infections and the wide variety of clinical symptoms don't allow to precise a clinical diagnosis. We will try to bring some bases allowing, by the help of laboratory an etiologic diagnosis. This diagnosis is essential for providing an efficient prevention. We will approach some parameters which we have been confronted with as regards Canine Distemper and Canine Adenovirosis. Our purpose is, through these examples of the canine pathology, to confirm and complete some other similar situations which can appear in other animal species.  相似文献   
94.
From the reasons that canine coronavirus (CCV) grows more efficiently than feline coronavirus in a cell culture and they are mutually related in their antigenicities, an enzyme-linked immunosorbent assay (ELISA) using CCV-infected feline kidney (CRFK) cells as substrate antigens was developed for detection of anti-coronavirus antibodies in cats. It was indispensable for generating coronavirus-specific ELISA antibody activities that the sample was applied to the mock-infected, normal CRFK cells in parallel with the CCV-infected cells and then the optical density values given by the mock-infected cell antigen were subtracted from those given by the virus-infected cell antigen. On the basis of ELISA antibody titers obtained in sera from the cats experimentally infected with CCV and from the spontaneous feline infectious peritonitis (FIP) cases, the ELISA described in the present study was found to be applicable as a simple and easy serologic test which was able to detect anti-coronavirus antibodies as efficiently as the indirect immunofluorescence assay with homologous FIP virus.  相似文献   
95.
低脂无臭蛹蛋白粉的制备方法   总被引:13,自引:0,他引:13  
吴建一  魏克民 《蚕业科学》2003,29(3):314-317
研究分析了蚕蛹中油脂的存在形式。采用溶剂浸出整蛹脱脂的方法 ,通过多次脱脂并除臭后提取出无异味的蛹蛋白 ,可用于食品添加剂。制成的蛹蛋白中含油脂 1 8%、水分 5 8%、灰分 1 4 %、总氮 13 9%、氯化物 (以氯计 ) <0 0 5 %、砷 0 94mg/kg、汞 0 5 2mg/kg、重金属总量 <5mg/kg ;微生物检验菌落总数为 5 10cfu·g-1,大肠菌群 9× 10 -3 MPN·g-1,沙门氏菌、贺氏菌、金黄色葡萄球菌均未检出 ,霉菌总数 <10cfu·g-1,酵母菌总数 <10cfu·g-1,符合食品卫生标准。  相似文献   
96.
叙述了电磁场有限元分析的理论基础,给出了油气输送管道漏磁检测中的漏磁场,用ANSYS软件包对具体实例进行了分析,得到了漏磁场的空间分布、磁感应强度及漏磁信号图等。分析结果有助于全面认识空间中漏磁场,可为油气输送管道提供缺陷定量化检测依据。  相似文献   
97.
A group of SPF cats were moderately susceptible to the causal organism of contagious equine metritis (CEM) following intra-uterine or intrapreputial challenge with an Irish streptomycin resistant strain isolated from a clinically infected mare. Subclinical infections were established in only 50% of the cats, none of which became long-term carriers of the organism. Cytological examination of vaginal smears was of no diagnostic value in confirming infection in inapparently infected cats. Bacteriological responses after primary or secondary challenge with the CEM organism were essentially similar, with one exception, a female cat in which there was possible evidence of local immunity persisting after the primary infection. Efforts to reactivate shedding subsequent to the immediate post-challenge period were unsuccessful. Throughout the experimental period, the cats remained sero-negative to the complement-fixation test, and they failed to develop any significant increase in the levels of antibody activity as measured by the kinetics-based ELISA or KELA system. On day 89 after primary challenge, the cats were euthanized and various sites in the genitourinary tract and the internal iliac lymphatic glands subjected to bacteriological and pathological examination for evidence of CEM infection with negative results. The findings of this study, although establishing the transmissibility of the CEM organism for the cat, demonstrate the limited value of this species as an experimental model system for the disease in the horse.  相似文献   
98.
A comparison of the mitogenic effects of a phorbol ester on lymphocytes from bovine spleen, lymph node and peripheral blood.Bovine lymphocytes from three tissues, lymph node, spleen and peripheral blood were compared for their mitogenic responses to 12-O-tetraecanoylphorbol-13-acetate (TPA), a phorbol ester tumor promoter. TPA alone was found to be either not mitogenic or caused only a weak response when compared with the mitogenic lectin phytohemagglutinin (PHA). Of the three lymphocyte preparations, blood cells showed the greatest proliferative response to TPA. However, all three, lymph node, blood and spleen cells, showed a co-mitogenic response to TPA. That is, TPA synergistically enhanced DNA synthesis in cells stimulated with a suboptimal concentration of PHA.  相似文献   
99.
A 4-year-old, intact male Dogue de Bordeaux dog with congenital valvular pulmonic stenosis, tricuspid valve dysplasia, and chronic atrial fibrillation underwent ultrasound-guided balloon valvuloplasty in addition to pharmacological treatment. Owner compliance to prescribed pharmacotherapy proved very poor, and concerns developed regarding the ability to successfully control heart rate and symptoms using drug therapy alone. These concerns were addressed by the implantation of a novel vagal stimulation system that was programmed to prevent a ventricular rate of >145 bpm. Consequently, post-operative ventricular response rate decreased from up to 250 to 140 bpm. Successful ventricular rate control was maintained for 291 days post-operatively, following which euthanasia was elected by the owner due to persistent right-sided congestive heart failure. To the authors' knowledge, this is the first report of successful continuous rate control using a vagal stimulating system in a closed-chest, client-owned dog with chronic atrial fibrillation secondary to spontaneously occurring organic heart disease.  相似文献   
100.
The yak is one of the most important and economically useful animals for highlanders. The decline in the yak population requires effective measures for the conservation and multiplication of elite germplasm. A standardized protocol will simplify the freezing and warming of yak embryos in straw and facilitate embryo transfer. In this work, we investigated a one‐step protocol that uses a stable basal medium, which comprised a warming medium (1.08 M sucrose) and a freezing medium (EFS40). We also assessed the effects of the new transfer method on embryo survival. A total of 145 yak frozen embryos were thawed in a standard medium system. The one‐step protocol led to a high recovery percentage (84.93) of yak embryos that survived vitrification and warming. The in vitro survival rates of these embryos significantly different from those of embryos frozen–thawed via the conventional method. The 95 embryos frozen–thawed via our one‐step protocol were then implanted in selected recipients. Thirty‐six singleton pregnancies were established. In conclusion, the proposed one‐step method is a simple, safe, and standardized freezing–thawing protocol that ensures embryo survival and quality under field conditions. This study establishes new possibilities for the widespread use of embryo transfer in yaks.  相似文献   
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