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991.
992.
An Abyssinian cat examined because of hypoproteinemia and weight loss was found to have epitheliotropic T-cell lymphosarcoma of the gastrointestinal tract. Neoplastic lymphocytes infiltrated the epithelium and lamina propria of the stomach, small intestine, and large intestine. Metastatic foci were found in the lungs and the musculature of the right hind limb. Chemotherapy resulted in transient shrinkage of the lung and limb masses; however, these masses grew to approximately their original size within 2 weeks after initiation of treatment, and the cat was euthanatized.  相似文献   
993.
The results of vaccination trials carried out on pups with maternally derived antibodies (MDA) to canine parvovirus (CPV), using a modified‐live CPV‐2b variant vaccine (29‐97/40 strain), are reported. The vaccine was able to overcome the obstacle of MDA, and to elicit protective immunity in 100% of the pups whose antibody titres were 1:10–1:40, 83% of the pups with titres of 1:80, 57% of the pups with titres of 1:160, and even in 60% of the pups with antibody titres of 1:320.  相似文献   
994.
Recombinant adenoviral vectors have emerged as an attractive system for veterinary vaccines development. However, for poultry vaccination a very important criterion for an ideal vaccine is its low cost. The objective of this study was to test the ability of chicken CD154 to enhance the immunogenicity of an adenoviral vector-based vaccine against avian influenza virus in order to reduce the amount of antigen required to induce an effective immune response in avian. Chickens were vaccinated with three different doses of adenoviral vectors encoding either HA (AdHA), or HA fused to extracellular domain chicken's CD154 (AdHACD). Hemagglutination inhibition (HI) assay and relative quantification of IFN-γ showed that the adenoviral vector encoding for the chimeric antigen is able to elicit an improved humoral and cellular immune response, which demonstrated that CD154 can be used as a molecular adjuvant allowing to reduce in about 50-fold the amount of adenoviral vector vaccine required to induce an effective immune response.  相似文献   
995.
Disodium-fosfomycin pharmacokinetics has been studied in different species after oral, intravenous, intramuscular and subcutaneous administration. At present there are neither documented clinical experiences of the use of fosfomycin in pigs nor any published studies in weaning piglets, although it is a period of high incidence of infectious diseases. The pharmacokinetics and the bioavailability of sodium fosfomycin were studied in post weaning piglets after intravenous and intramuscular administration of 15 mg/kg of body weight. Plasma concentrations were measured by a high-performance liquid ms/ms. After IV administration the area under the fosfomycin concentration:time curve in plasma was AUC(0–12) of 120.00 ± 23.12 μg h/ml and the volume of distribution (Vd) of 273.00 ± 40.70 ml/kg. The elimination was rapid with a plasma clearance of 131.50 ± 30.07 ml/kg/h and a T1/2 of 1.54 ± 0.40 h. Peak serum concentration (Cmax), Tmax, AUC(0–12) and bioavailability for the IM administration were 43.00 ± 4.10 μg/ml, 0.75 ± 0.00 h, 99.00 ± 0.70 μg h/ml and 85.5 ± 9.90% respectively. Different authors have determined a minimum inhibitory concentration (MIC90) ranging from 0.25 μg/ml for Streptococcus sp. and 0.5 μg/ml for Escherichia coli. Considering the above, and according to the values of plasma concentration vs time profiles observed in this study, effective plasma concentrations of fosfomycin for sensitive bacteria can be obtained following IV and IM administration of 15 mg/kg in piglets.  相似文献   
996.
997.
Carrier-free electrophoresis was used to separate subpopulations of bovine alveolar macrophages according to their electrical surface charges. The electrophoretic mobility of the macrophages changed significantly as a function of the time of cultivation in vitro. After 20 h, three subgroups were identified which differed in their specific contents of lysosomal hydrolases, alpha-naphthyl acetate esterase, and alkaline phosphodiesterase. By comparing the findings with results from the literature it was concluded that the subgroups correspond to different stages of maturation and that the fraction moving fastest may be the most mature fraction. The results were not influenced by phagocytosis and the presence or absence of Ca2+.  相似文献   
998.
Addition of granulosa cells (GC) (1.10(6)/ml) affected maturation of non-ovulatory oocytes of cattle and caused delay in nuclear maturation (60.8 versus 35.3 or 37.1 percent). In vitro use of pre-incubated GC in the process of maturation led to higher rates of fertilisation (49.4 versus 25.2 or 21.0 percent) and of cleavage (29.6 versus 13.3 or 9.1 percent). No explanation has yet been found for different oocyte behaviours in response to use of fresh or pre-incubated GC. Transfer of seven embryos from maturation with GC as well as in vitro fertilisation and development to four recipients resulted in the birth of one female calf.  相似文献   
999.
In three Austrian rabbit units (two in the west, one in the east) heavy losses occurred in April/May 1989. The clinical course (deaths in adult animals, haemorrhagic diathesis) of the disease was indicative for an infection with the RHD-virus. Necropsy confirmed the suggestive clinical diagnosis as bleeding of the nostrils, hyperaemia in the respiratory tract, spleen tumor, partly decolorized livers, hyperaemia of kidneys with rare petechias could be observed. Histologic examination revealed centrolobular liver necrosis, lung bleeding and edema, tumor of spleen and atrophy of spleen follicles. Rabbits infected with organ suspensions died within 48 hours. The organ suspensions and the suspensions of the already necropsied animals showed a haemagglutination titer for above 1:100. This reaction could be inhibited with a specific RHD-antiserum. The intramuscular application of a RHD-reference strain in one hare, two wild rabbits and a rabbit did not induce clinical disease or death of the leporids during a six week observation period. The rabbit died within 48 hours post infection. However the hare and wild rabbits showed high antibody titers by ELISA at the end of the observation period. Before infection the two wild rabbits were serologically negative.  相似文献   
1000.
The involvement of prolactin in the periparturient rise in the faecal nematode egg count in sheep was investigated. Ostertagia circumcincta larvae (5000 third stage larvae three times weekly) were administered to adult immune ewes from three weeks before parturition to three weeks afterwards. Ten ewes were injected twice daily with 2-bromo-alpha-ergocryptine (bromocriptine), an antagonist of prolactin secretion, for two weeks starting two days after lambing while 10 ewes remained untreated. Bromocriptine treatment was initiated approximately two weeks pre partum in three other ewes. Plasma pepsinogen concentrations rose significantly by one week after the start of O circumcincta larval challenge in all the ewes but faecal egg counts remained negative until approximately one week post partum. Plasma prolactin concentration was reduced to a very low level in all bromocriptine treated ewes but this did not alter the dynamics of the periparturient rise in faecal egg counts. Neither cell-mediated nor humoral immunity of the ewes, as assessed by their sensitivity to BCG inoculation and by antibody titre raised against horse red blood cells, respectively, were impaired during the rise in faecal egg count, nor were these parameters altered by manipulation of plasma prolactin concentration. Lamb growth rate was not retarded by low plasma prolactin concentration in the bromocriptine treated ewes. These results are not consistent with the generally held hypothesis that elevated plasma prolactin concentration is directly associated with the periparturient rise.  相似文献   
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