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1.
Waner T Nyska A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):78-80
Serum concentrations of glucose, cholesterol, triglycerides, and serum alkaline phosphatase activity were measured over different periods of time of food deprivation in male rats. Thirty percent of non-fasted rat's sera was found to be lipemic. At 16 hours of fasting, glucose levels dropped by 30% compared to the level of the non-fasting control group, and remained at a relatively constant level for up to 48 hours of fasting. Triglyceride concentrations decreased at 16 hours after fasting. Serum cholesterol levels were not changed at any of the fasting periods compared to the non-fasted control group. Alkaline phosphatase activity was decreased at 8 hours of fasting, with further declines in activity of the serum enzyme seen at 16, 24, and 48 hours of fasting. It was concluded that at 16 to 18 hours fasting, a non-absorptive state had been reached in male rats. 相似文献
2.
The structure of liquid water is described by three atom pair distribution functions gOO(r), gOH(r), and gHH(r). These functions have now been derived from neutron diffraction data on four mixtures of light and heavy water. They will provide a crucial and sensitive test for proposed models of liquid water. 相似文献
3.
Yuval Ramot Michal Steiner Netanel Amouyal Yossi Lavie Guy Klaiman Abraham J. Domb Abraham Nyska Tal Hagigit 《Journal of toxicologic pathology》2021,34(1):11
Fracture-related infections remain a leading cause of morbidity and mortality. We aimed to establish a simple contaminated radial osteotomy model to assess the efficacy of a biodegradable polymer poly(sebacic-co-ricinoleic acid) [p(SA-RA)] containing 20% w/w gentamicin. A unilateral transverse osteotomy was induced in Sprague-Dawley (SD) rats, followed by application of Staphylococcus aureus suspension over the fracture. After successfully establishing the contaminated open fracture model, we treated the rats either systemically (intraperitoneal cefuroxime), locally with p(SA-RA) containing gentamicin, or both. Control groups included non-contaminated group and contaminated groups that were either untreated or treated with the polymer alone. After 4 weeks, the bones were subjected to micro-CT scanning and microbiological and histopathology evaluations. Micro-CT analysis revealed similar changes in the group subjected to both local and systemic treatment as in the non-contaminated control group. Lack of detectable bacterial growth was noted in most animals of the group subjected to both local and systemic treatment, and all samples were negative for S. aureus. Histopathological evaluation revealed that all treatment modalities containing antibiotics were highly effective in reducing infection and promoting callus repair, resulting in early bone healing. While p(SA-RA) containing gentamicin treatment showed better results than cefuroxime, the combination of local and systemic treatment displayed the highest therapeutic potential in this model. 相似文献
4.
5.
The Use of Antigen-capture Enzyme-linked Immunosorbent Assay (ELISA) for the Diagnosis of Rinderpest and Peste des Petits Ruminants in Ethiopia 总被引:1,自引:1,他引:0
Rinderpest had been reported in most parts of Ethiopia when the Pan African Rinderpest Campaign (PARC) was launched. As a result of intensive disease investigation and strategic vaccination, most parts of the country are now considered provisionally free, and widespread vaccination has been replaced by clinical and serological surveillance. Details of any episodes of disease are recorded and followed up after laboratory confirmation of suspected cass using antigen-capture ELISA. This paper is based on observations on the performance of the antigen detection ELISA compared to the agar gel immunodiffusion (AGID) test, which also differentiates rinderpest from peste des petits ruminants (PPR). The stability of the specific viral antigen was monitored for 4 days, and rinderpest and PPR antigens were still detected, depending on the type of specimen. Antigen capture ELISA is more rapid, sensitive and virus specific than the AGID. Even if the cold chain of the specimen is compromised for a day or two during sample collection and submission, the specimen may still be suitable for testing by ELISA. 相似文献
6.
An investigation was carried out into an outbreak of respiratory disease complex (RDC) in 3641 Menz and Awassi×Menz cross sheep in Central Ethiopia between 1998 and 1999 by clinical, serological, microbiological, post-mortem and histopathological examinations. The monthly incidence of RDC varied from 2.8% to 4.0% and the prevalence was as high as 17%. The case fatality rate was 18%, despite culling of sick sheep. Over 76% of the morbidity occurred in adults, followed by 19% among weaners. Similarly, 62% of the mortality was in adults. However, 27% of the mortality occurred in lambs despite the low morbidity in the group. Significant breed and age differences were seen in the morbidity and mortality rates (p<0.05). Clinical signs, gross and microscopic lesions and serological and bacteriological examinations showed an interplay of several causes of the RDC, including pestes des petits ruminants (PPR) (72.3%, serologically confirmed), lung worms, maedi-visna, bacterial bronchopneumonia (staphylococcal and streptococcal), enzootic pneumonia and some fungal infections. Cold temperatures, which may be as low as –8.5°C at night, are major predisposing factors along with managemental stresses. Vaccination of animals with a homologous PPR vaccine appeared to decrease dramatically the occurrence of the disease, showing that PPR played an important role in the outbreak. Several of the pathogens do not appear to be individually capable of causing the respiratory disease. Appropriate strategies for the prevention of RDC are suggested. 相似文献
7.
Musser RE Goodband RD Tokach MD Owen KQ Nelssen JL Blum SA Campbell RG Smits R Dritz SS Civis CA 《Journal of animal science》1999,77(12):3296-3303
Sows of differing parities and genetics were used at different locations to determine the effects of feeding added L-carnitine during lactation on sow and litter performance. In Exp. 1, sows (n = 50 PIC C15) were fed a lactation diet (1.0% total lysine, .9% Ca, and .8% P) with or without 50 ppm of added L-carnitine from d 108 of gestation until weaning (d 21). No differences in litter weaning weight, survivability, sow ADFI, or sow weight and last rib fat depth change were observed. Number of pigs born alive in the subsequent farrowing were not different (P>.10). In Exp. 2, parity-three and -four sows (n = 115 Large White cross) were used to determine the effect of feeding 0, 50, 100, or 200 ppm of added L-carnitine during lactation (diet containing .9% total lysine, 1.0% Ca, and .8% P) on sow and litter performance. No improvements in the number of pigs or litter weights at weaning were observed (P>.10). Sows fed added L-carnitine had increased weight loss (linear; P<.04), but no differences (P>.10) were observed in last rib fat depth change or subsequent reproductive performance. In Exp. 3, first-parity sows (n = 107 PIC C15) were fed a diet with or without 50 ppm of added L-carnitine during lactation (diet containing 1.0% total lysine). Sows fed added L-carnitine tended (P<.10) to have fewer stillborn and mummified pigs than controls (.42 vs .81 pigs). No differences were observed for litter weaning weight, survivability, or subsequent farrowing performance. Feeding 50 to 200 ppm of added L-carnitine during lactation had little effect on sow and litter performance. 相似文献
8.
Pregnancy detection in cows by pulse mode ultrasound
Two commercially available pulse mode ultrasound instruments for pregnancy detection in cows were examined by testing 50 pregnant Friesian cows twice weekly. Absolutely reliable results were obtained after d 181 ("Cow-Tone") and d 221 of pregnancy (Preg-Alert 7 respectively. A newly constructed instrument ("HK-Rheintechnik") operating with greater wavelength (0,7 MHz) was tested in a similar fashion on 62 pregnant cows. Zt produced absolutely reliable results from d 135 of pregnancy on, i.e. 46 days sooner than the best of the commercial instruments tested . 相似文献
Two commercially available pulse mode ultrasound instruments for pregnancy detection in cows were examined by testing 50 pregnant Friesian cows twice weekly. Absolutely reliable results were obtained after d 181 ("Cow-Tone") and d 221 of pregnancy (Preg-Alert 7 respectively. A newly constructed instrument ("HK-Rheintechnik") operating with greater wavelength (0,7 MHz) was tested in a similar fashion on 62 pregnant cows. Zt produced absolutely reliable results from d 135 of pregnancy on, i.e. 46 days sooner than the best of the commercial instruments tested . 相似文献
9.
The ant Iridomyrmex pruinosus utilizes 2-heptanone as an alarm pheromone. The activities of 49 ketones and 35 nonketones as alarm pheromones for this species were determined. The molecular shapes of these compounds were assessed by submitting silhouette photographs of their molecular models to a pattern recognition machine. A highly significant correlation exists between molecular shape and alarm activity. 相似文献
10.