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101.
The significance of food allergy as a primary cause for gastrointestinal disturbances in domestic animals, especially calves and piglets, is discussed. The immunological backgrounds and pathogenesis are described in some detail. The clinical and pathological manifestations in animals are related to those in man. Diagnostic possibilities, therapy and prevention, as far as known in animals, are mentioned and, based on human experiences, further extensions are proposed.  相似文献   
102.
Comparative serological evaluation of avian influenza vaccine in turkeys   总被引:1,自引:0,他引:1  
Four- and six-week-old turkeys were vaccinated subcutaneously using avian influenza virus (AIV) A/Duck/613/MN/79 (H4N2) killed oil-emulsion vaccine. Sequential serological tests using agar gel precipitin (AGP), hemagglutination inhibition (HI), and enzyme-linked immunosorbent assay (ELISA) for measuring antibodies to AIV were performed up to 4 weeks postvaccination, when birds were challenged intranasally using A/Turkey/MN/80 (H4N2) live AIV. The ELISA was 25 to 1600 times more sensitive than the HI test and was able to detect antibody production earlier than the HI test. All turkeys with an ELISA titer of greater than or equal to 800 were protected against homologous challenge, as measured by virus recovery 3 days postchallenge. Four turkeys out of 20 serologically negative by AGP and HI tests but ELISA-positive were protected.  相似文献   
103.
104.
Teratogenic effects of methylparathion / Wofatox 50 EC/ and Parathion 20 WP as positive control material were tested in pheasant embryos. On the 12th day of incubation 0.1 ml of the emulsions or suspensions of the insecticides at different concentrations was inoculated into the air space of embryonated eggs. The following dose levels were employed: 27 and 270 mg/kg egg of Wofatox 50 EC, and 10 mg/kg of Parathion 20 WP. Morphological changes were evaluated by macroscopic, skeletal staining and light microscopic examinations of the embryos. Primary hypoplasia or atrophy developed in the cervical musculature /m. longus colli/ accompanied by lordosis and scoliosis of the cervical spine. In most cases we also found cyllosis .  相似文献   
105.
Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of microscopic postmortem changes in the adrenal glands of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. The sequence of microscopic postmortem changes was similar in all chickens except at 18 C, when karyorrhexis of cortical and medullary cells was observed. Cellular changes occurred earlier at 29 C than at 18 C and in dry chickens but not in chickens wet with detergent solution before storage, although slight quantitative and qualitative differences between wet and dry chickens were noted. Medullary cells underwent postmortem changes earlier than cortical cells. Nuclei of medullary cells decreased in size, with chromatin clumping leading to pyknosis, followed by cytoplasmic vacuolation, cellular shrinkage, and finally karyolysis and cell dissociation. Cortical cells had nuclear chromatin marginated, nuclei reduced in size initially, and some nuclear fading, followed by pyknosis and karyolysis. Karyorrhexis was not a prominent feature of cortical and medullary cells, although it occasionally occurred before pyknosis. Cytoplasm of cortical cells remained eosinophilic, granular, and vacuolated, but vacuoles became finer later. Pyknotic medullary cells with vacuolated cytoplasm were observed as early as 3 hr postmortem, regardless of the temperature. Diffuse pyknosis of medullary cells was noted at 18 hr in chickens held at 29 C and at 48 hr in chickens held at 18 C. Marked cortical pyknosis was noted only at 36 hr in wet chickens held at 29 C, when bacterial invasion started. Dry chickens held 36 hr at 29 C had diffuse cellular dissociation, karyolysis and cytoplasmic acidophilia, and marked bacterial invasion. Erythrocytes were pyknotic and had cytoplasmolysis. It was concluded that adrenal glands may still be useful for histopathological examination before 18 hr at 29 C and before 48 hr at 18 C.  相似文献   
106.
107.
A radiographic technique was used to identify and characterize segmental diaphragmatic movement in anesthetized ponies breathing spontaneously and with controlled ventilation with and without muscle relaxant-induced paralysis. Paralyzed mechanically ventilated ponies were also studied at varying peak inspiratory pressures. Controlled ventilation induced a change in pattern of diaphragmatic displacement which was accentuated by paralysis and increased inspiratory pressure. In conclusion, these results indicate that uneven distribution of inspired gases is not corrected by mechanical ventilation. Furthermore, increased tidal volume during mechanical ventilation is largely wasted because this increased volume is distributed principally to the poorly perfused nondependent lung. Thus, while mechanical ventilation can alleviate hypoventilation, i.e., will decrease PaCO2, it will be of limited value in relieving arterial hypoxemia due to venous admixture in anesthetized patients.  相似文献   
108.
This is the first of a series of capsule reviews published by the World Small Animal Veterinary Association ‐ Global Pain Council (WSAVA‐GPC). Each of these short articles provides a brisk assessment of the scientific evidence in specific aspects of pain management, including analgesic techniques, recommendations and controversies surrounding their use. In this first capsule review, the scientific evidence available on the long‐term use of non‐steroidal anti‐inflammatory drugs in cats with concomitant chronic pain and chronic kidney disease is discussed.  相似文献   
109.
运用AHP-CRITIC复合加权法评价不同发育期苦水玫瑰的品质。以不同发育期的苦水玫瑰为研究对象,测定总多糖、总黄酮、总多酚含量及抗氧化活性,采用AHP-CRITIC复合加权法综合评价不同发育期苦水玫瑰的品质。结果发现抗氧化IC50、总黄酮、总多酚、总多糖4个指标成分的复合权重分别为0.294 1、0.152 3、0.158 8、0.394 8;幼蕾期、花蕾期、盛开期苦水玫瑰质量综合评分分别为54.362 0、38.451 9、33.801 9,即幼蕾期苦水玫瑰的质量最好,花蕾期次之,盛开期较差。说明通过化学成分和生物活性作用综合评价不同发育期苦水玫瑰的品质,幼蕾期苦水玫瑰品质最好。  相似文献   
110.
番茄品种耐弱光性的综合评价   总被引:32,自引:4,他引:32  
研究了苗期弱光条件对幼苗素质,开花,果实大小及产量的影响,采用模糊数学的隶属法对品种的耐弱光性进行评价,并探讨了番茄耐弱光性状的鉴定方法,结果表明,苗期弱光对幼苗素质影响最大,其次影响开花,果实大小和产量,春雷2号和春雷1号属于耐弱光惭弱的品种,白果强丰属不耐弱光品种。  相似文献   
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