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261.
262.
The aim of this study was to generate a transgenic mouse that ubiquitously expressed enhanced green fluorescent protein (EGFP) under the control of the murine phosphoglycerate kinase 1 promoter by allotransplantation of transgenic mouse ovaries. The EGFP transgenic mice expressed green fluorescence in many organs, and the fluorescence was detected as early as the embryonic stage. Ovaries from the EGFP transgenic mice were allotransplanted into recipients and these mice were mated with normal male mice. Histological sections of EGFP‐allotransplanted ovaries from the recipient mice showed the well development and formation at follicles and corpora lutea. The green fluorescence was clearly detectable at the allotransplanted section of the ovaries, which had fused with the normal ovary. The average size of the first litter from these mice was 6.8 ± 1.2 pups per recipient, and 17.8% of the pups expressed EGFP. These results demonstrated that allotransplantation of transgenic ovaries can restore a normal reproductive lifespan and can be used to generate a ubiquitously expressing EGFP animal model. 相似文献
263.
By selecting pseudorabies virus (PrV) as a model virus, this study assessed the feasibility of applying viral inactivation strategies to manufacturing medicinal products from the milk of transgenic sows. The efficacy of heat, acidic/alkaline and detergent treatments was also evaluated with respect to their ability to inactivate PrV in milk samples. Experimental results indicate that PrV was inactivated obviously at least 7.125 log10 for 30 min at 60 degrees C. At alkaline values of pH 10 and acidic value of pH 4, PrV infectivity was reduced to 3.625 log10 and exceeded 5 log10, respectively. Moreover, PrV virus was inactivated efficiently (> 3.875 log10) by using 0.25-1% of Triton X-100 treatment and without a loss of biological activity of the recombinant human coagulation factor IX (rhFIX). RESULTS: of this study demonstrate the effectiveness of the proposed detergent inactivation method for PrV inactivation of rhFIX production from transgenic products, especially in milk materials. 相似文献
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SP DJORDJEVIC GJ EAMENS LF ROMALIS PJ NICHOLLS V TAYLOR J CHIN 《Australian veterinary journal》1997,75(7):504-511
Objective To investigate the protective efficacy of a pool of denatured membrane protein antigens of Mycoplasma hyopneumoniae (J strain) in the molecular size range 70 to 85 kDa (F3 antigen) in combination with adjuvants for pigs challenged with M hyopneumoniae .
Design A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses.
Procedure F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection.
Results Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection.
Conclusion Pigs vaccinated with M hyopneumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia. 相似文献
Design A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses.
Procedure F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection.
Results Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection.
Conclusion Pigs vaccinated with M hyopneumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia. 相似文献
266.
The Effect of Sperm Concentration and Storage Vessel on Quercetin‐Supplemented Rabbit Semen During Chilled Storage 下载免费PDF全文
Extending the shelf life of chilled rabbit spermatozoa is vital for the expansion of the farmed rabbit industry. This study evaluated the relationship between sperm concentration and packaging on in vitro quality of chilled rabbit semen over 96 h. Semen was collected from adult bucks (n = 4) and pooled at 37°C following evaluation. Pooled ejaculates were diluted with a Tris‐based extender supplemented with 100 μm quercetin to a concentration of 15, 30 or 60 × 106 spermatozoa/ml, packaged into plastic tubes or 0.5‐ml straws and stored at 15°C. Sperm quality was assessed by computer‐assisted sperm Analysis [total motility (tMOT)] and flow cytometry [viability, acrosome integrity, H2O2 production, plasma membrane disorder, apoptosis and DNA fragmentation index (DFI)] at 0, 48, 72 and 96 h. From 48 h, concentrations of 30 and 60 × 106 spermatozoa/ml reported the highest tMOT, irrespective of storage vessel (p < 0.05). Storage in straws reduced oxidative stress and improved plasma membrane stability. The %DFI, mean DFI and SD‐DFI were increased in spermatozoa stored in tubes compared with straws (p < 0.05). Although the use of low sperm concentrations in artificial insemination doses would facilitate greater dispersion of genetically superior rabbit bucks, dilution to 15 × 106 spermatozoa/ml had a detrimental impact on motility. As such, chilled storage at 30 × 106 spermatozoa/ml may provide a suitable balance between motility and H2O2 production to best maintain overall sperm function and should be evaluated in a large‐scale AI trial. 相似文献
267.
Endo H Hikida T Motokawa M Chou LM Fukuta K Stafford BJ 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):873-879
Skull size and shape were examined among 14 species of the tree shrews (Tupaia montana, T. picta, T. splendidula, T. mulleri, T. longipes, T. glis, T. javanica, T. minor, T. gracilis, T. dorsalis, T. tana, Dendrogale melanura, D. murina, and Ptilocercus lowii). The bones of face were rostro-caudally longer in T. tana and T. dorsalis, contrasting with T. minor and T. gracilis, D. melanura, D. murina and P. lowii which have smaller facial length ratios. The arbo-terrestrial species (T. longipes and T. glis) were similar to terrestrial species in length ratios of bones of face unlike the other arbo-terrestrial species (T. montana, T. picta, T. splendidula, and T. mulleri). We propose that T. longipes and T. glis have adapted to foraging for termites and ants as have T. tana and T. dorsalis. Additionally small body size in T. javanica may be the result of being isolated in Java. We separated the species into 5 groups from the measurment values of skulls: 1) Terrestrial species; T. tana and T. dorsalis, 2) Arboreal species; T. minor and T. gracilis, 3) Arbo-terrestrial species group 1: T. montana, T. splendidula, T. picta and T. mulleri, and T. javanica, 4) Arbo-terrestrial species group 2: T. glis and T. longipes, 5) Arboreal species of Dendrogale and Ptilocercus. Principal component analysis separated species into 8 clusters as follows: 1) T. tana, 2) T. dorsalis, 3) T. montana, T. splendidula, T. picta and T. mulleri, 4) T. glis and T. longipes, 5) T. javanica, 6) T. minor and T. gracilis, 7) D. melanura and D. murina, and 8) P. lowii. We suggest that these clusters correspond to behavioral strategies and peculiarities observed in foraging, feeding and locomotion in each species. 相似文献
268.
A H Parks J A Stick W A Arden C C Chou S M Hengemuhle 《American journal of veterinary research》1989,50(1):54-58
The influence of distention (high baseline intraluminal pressure) and neostigmine methylsulfate on intestinal vascular resistance, oxygen uptake, and intraluminal pressure changes (rhythmic contractions) was studied in terminal jejunal segments, which were perfused at a constant rate, in 16 anesthetized ponies. When baseline intraluminal pressure was increased to 10 mm of Hg, the intestinal vascular resistance and amplitude of rhythmic contractions were increased. Neostigmine induced cyclic increases in amplitude of rhythmic contractions whether intraluminal pressure was 0 or 10 mm of Hg. Neostigmine also increased intestinal oxygen uptake at intraluminal pressures of 0 mm of Hg, but not at 10 mm of Hg, and vascular resistance was not altered at either intraluminal pressure. The results indicate that intestinal hemodynamics are adversely affected by distention. Further, neostigmine did not adversely affect intestinal hemodynamics while increasing rhythmic contractions, suggesting that neostigmine may be useful in the treatment of ileus in equids. 相似文献
269.
270.
The goals of this study were to elucidate the temporal and quantitative relationships between caffeine and its major bioactive metabolites in blood and cerebrospinal fluid (CSF) and to characterize the pharmacokinetic-pharmacodynamic relationship for caffeine-induced changes in spontaneous locomotor activity in the horse. We hypothesized that caffeine and its metabolites distribute efficiently into the CSF to antagonize adenosine A1 and A2a receptors and that spontaneous locomotor activity correlates well with caffeine and/or metabolite concentrations in CSF and blood. A microdialysis system was developed to allow simultaneous monitoring of locomotor activity and collection of CSF and blood samples for pharmacokinetic analysis. CSF concentrations of caffeine and its metabolites were evaluated to determine the percentage of central adenosine receptor blockade by the established standard inhibition curves. Caffeine increased the spontaneous locomotor activity for up to 4 h in a dose-dependent manner. After 3 mg/kg caffeine administration, blood caffeine concentration as well as locomotor activity increased sharply to near peak level while CSF caffeine concentrations exhibited a slow rise to a steady-state 75 min later. High correlation coefficient was found between locomotor activity and caffeine concentrations in blood (R(2 )=0.95) and in CSF (R(2) = 0.93). At 3 mg/kg dosage, theophylline was the only detectable caffeine metabolite in the CSF. The concentrations reached in the CSF were sufficient to partially block central adenosine A1 (14% blockade) and A2a (11% blockade) receptors. There were no statistically significant differences between the pharmacokinetics of caffeine in the blood and CSF. This study provides novel evidence that locomotor stimulation in horses is closely correlated with caffeine concentrations in the blood and CSF and, furthermore, is consistent with blockade of central adenosine receptors. 相似文献