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1.
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.
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   
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4.
A. GERA  J. COHEN 《Plant pathology》1990,39(3):558-560
A strain of cucumber mosaic virus (CMV) was isolated from phlox plants raised from imported cuttings and grown in plastic tunnels. The infection was acquired from local sources. Virus identification was based on electron microscopy, host range, aphid transmission, serology and physical properties.  相似文献   
5.
Two methods for evaluating the joint action of fungicides in mixtures were analysed. In order to obtain a relatively rapid answer on the type of interaction between fungicides in a mixture (additivity, synergism or antagonism), one can apply the Abbott formula to data on fungus survival. Tests with this method will not be accurate at high effective dose values. A more accurate determination of the joint action of fungicides can be made by the Wadley method, applied to data on effective doses. This involves more experimental work than the Abbott method. Optimization of mixing ratios of fungicides required a set of experimental data on effective doses with several mixing ratios.  相似文献   
6.
The effects of powdery mildew (caused by Sphaerotheca fuliginea )on muskmelon seedlings and the efficacy of seed treatment with systemic fungicides were examined under controlled environmental conditions. The fresh weight of seedlings infected with powdery mildew was substantially less than that of uninoculated seedlings 5 weeks after inoculation, and the inoculated seedlings shrivelled 1 week later. The fungicides fenarimol and triadimenol applied to the seeds did not affect germination and suppressed powdery mildew effectively when applied at a rate equivalent to 8 g fungicide product per kg seed. Under conditions moderately conducive to the pathogen, fenarimol markedly reduced disease severity and its effect when applied as a seed treatment was as effective as foliar treatment. When conditions were highly conducive to the pathogen, seed treatment with fenarimol was not effective. Development of powdery mildew and efficacy of the seed treatments were related to soil type: disease developed earlier and more intensely on seedlings grown in sandy soil than those in organic medium, and seed treatment had a more pronounced effect on seedlings grown in sandy soil. The results indicate that fungicidal treatment of muskmelon seeds may offer an adequate means of reducing powdery mildew infections on seedlings.  相似文献   
7.
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   
8.
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   
9.
A 2-year-old, neutered male Siberian Husky presented with depression, weight loss and an inability to prehend food and water. Cerebrospinal fluid was collected under general anaesthesia prior to euthanasia. The elevated white cell count comprised mostly mononuclear cells. Histological changes within the brain were variable and multifocal. Non-suppurative meningitis secondary to lymphoma was diagnosed. At necropsy, abnormal venous drainage of the right cranial and middle lung lobes was found. A dilated major pulmonary vein from these lobes passed across the lateral aspect of the right caudal lung lobe prior to entering the heart, and subpleural veins from the affected lobes were enlarged and tortuous. These vascular abnormalities were considered incidental. There were no apparent congenital abnormalities of the heart and the animal's clinical signs were related to lymphoma of the brain.  相似文献   
10.
Spirulina fusiformis was tested for its possible in vivo protective effects against cyclophosphamide (CP) and mitomycin-C (MMC) induced genotoxicity and oxidative stress in mice. Pre-treatment with S. fusiformis (250, 500 and 1000 mg kg(-1), p.o., daily for 5 days) significantly reduced the chromosomal damage and lipid peroxidation with concomitant changes in antioxidants and detoxification systems. All the three tested doses were effective in exerting a protective effect against CP and MMC.  相似文献   
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