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991.
Erythrocyte 5'-nucleotidase is thought to be involved in the maturation of erythrocytes. In the present study, in vitro incubation of canine erythrocytes demonstrated that significant inhibition of 5'-nucleotidase activity occurred in the presence of serum from dogs infected with Babesia gibsoni, when the enzyme was assayed with cytidine 5'-monophosphate (5'-CMP) and inosine 5'-monophosphate (5'-IMP) as substrates. The multiplication of B. gibsoni in in vitro culture also resulted in a significant decrease in the enzyme activity of erythrocytes in the culture. Furthermore, the infected serum and 5'-CMP retarded the maturation of canine reticulocytes in vitro. These results suggested that nucleotides such as 5'-CMP and 5'-IMP might accumulate in young erythrocytes and/or serum in dogs infected with B. gibsoni as a result of decreased activity of erythrocyte 5'-nucleotidase, resulting in the delayed maturation of reticulocytes.  相似文献   
992.
Six chicks (3–6 weeks of age) were taken randomly from each of 200 broiler farms in northern Jordan, these chicks were submitted for post-mortem and parasitological examinations. Seven Eimeria spp. were identified: E. acervulina, E. brunetti, E. maxima, E. necatrix, E. mivati, E. mitis, and E. tenella. Half (50%) of the farms surveyed had all six chicks infected, 23% of the farms were free of the infection. E. tenella was the most prevalent species (39%) followed by E. necatrix (12%), E. brunitti (12%), and E. maxima (10%). Prevalences did not vary by flock size. Also, neither the use of coccidiostat nor previous coccidiosis clinical outbreaks was associated with the prevalence of coccidiosis.  相似文献   
993.
Anti-Thy-1.1 nephritis in the rat is a popular experimental model for mesangial proliferative glomerulonephritis (GN). This model is characterized by direct binding of anti-Thy-1.1 antibody with Thy-1.1 antigen expressed on mesangial cells (MCs) of glomeruli in the rat. A single injection of anti-rat thymocyte serum (ARTS) results in GN with proteinuria and extensive mesangiolysis. Development of mesangiolysis and proteinuria are complement-dependent. We previously demonstrated Thy-1.1 antigen, similar to the rat, in thymocytes, brain cells and MCs of the kidney in the Mongolian gerbil (MG). In this study, we attempted to develop a MG nephritis model, but an injection of ARTS did not induce GN. An additional injection of guinea pig serum as a complement after ARTS injection resulted in anti-Thy-1.1 nephritis in MG. Degeneration of MCs and neutrophil infiltration were observed 1 hr after GP serum injection. Mesangiolysis and fibrin exudation occurred 12 hr after the injection and MC proliferation was apparent 7 days after the injection. In the complement-dependent hemolytic test, MG serum could not hemolyze sheep erythrocytes. These results suggested low activity, or depletion of some factors, in complements of MG serum.  相似文献   
994.
Abdominal pain (colic) in the horse is one of the most acute problems facing equine practitioners. Several causes and risk factors are associated with colic. The current study evaluated the incidence and associated risk factors of colic during a 1-year evaluation in horse farms of Kerman, Iran. The study investigated age, sex, breed, anthelmintic control program, and nutritional status of 128 horses of four breeds on six farms that took part in the study. The mean incidence density rate of colic in the horse population was 8.6% (11/128) in a year. Crossbred horses had more chance of developing colic (P < .05). Horses between the ages of 2 and 10 years also had more risk of developing colic (P < .05). There was no significant difference between sexes (P < .05), and nutritional factors were the most associated risk factors in the cases under study.  相似文献   
995.
Hyperglycemia is observed with exposure to organophosphorus (OP) pesticides. The aim of this study was to investigate the effects of malathion on secretion of insulin from rat pancreatic islets in vitro and in vivo. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400 ppm. For in vivo experiment, at the end of treatment, blood sample was obtained and plasma was separated. For in vitro experiment, the treated rats were anesthetized and underwent a laparatomy. The common bile duct was cannulated and the pancreas distended by injecting of cold collagenase V using peristaltic infusion pump. Islets were then hand picked under a stereomicroscope and cultured in the presence of various doses of glucose and KCl. Malathion at doses of 200 and 400 ppm increased plasma glucose and insulin concentrations and lowered activity of erythrocyte acetylcholinesterase. The isolated islets from pretreated animals with malathion 200 and 400 ppm showed lower glucose-stimulated insulin secretion while no change was observed in the presence of KCl. Light microscopic examination revealed that malathion causes patchy degenerative changes in pancreatic islets. Combination of in vivo and in vitro findings suggests that malathion induces a kind of insulin resistance that cannot overwhelm hyperglycemia. This action of malathion is mediated through disruption of islets mitochondrial function.  相似文献   
996.
The purpose of this study was to define ganglion cell density, size and topography in the retina of the mallard duck. After killing adult mallard ducks (Anas platyrhynchos var. domesticus), their eyes were removed using pentobarbital (30 mg/kg). The retinas were isolated, whole mount specimens were prepared by staining with 0.1% cresyl violet and then fixing the tissues for study. The retinal ganglion cells were counted, mapped and measured. The mean total number of ganglion cells was estimated at approximately 1.7 × 106 and the retinal area centralis had the highest ganglion cell density with 15 820 cells/mm2. The number of ganglion cell bodies was highest in the temporal area, followed by the nasal, dorsal and ventral areas. Ganglion cell size ranged from 56 to 406 μm2. A population of small ganglion cells persisted into the central area just above the optic disc and the largest soma area was in the ventral zone of the retina. This localization of ganglion cells suggests that the quality of vision is not equal in all the areas of the duck retina and the central part may have the highest vision quality as a function of the retinal ganglion cells.  相似文献   
997.
998.
Veterinary Research Communications - Avian influenza viruses (AIV) increase commercial and backyard poultry mortality and morbidity, reduces egg production, and elevates public health risk....  相似文献   
999.
A new C-benzylated chalcone from Desmos chinensis   总被引:1,自引:0,他引:1  
A new C-benzylated chalcone was isolated from the leaves of Desmos chinensis. Its structure was established as 2',4'-dihydroxy-3'-(2,6-dihydroxybenzyl)-6'-methoxychalcone on the basis of spectroscopic data.  相似文献   
1000.
The anticonvulsant activities of Crocus sativus stigma constituents, safranal and crocin, were evaluated in mice using pentylenetetrazole (PTZ)-induced convulsions in mice. Safranal (0.15 and 0.35 ml/kg, i.p.) reduced the seizure duration, delayed the onset of tonic convulsions and protected mice from death. Crocin (200 mg/kg, i.p.) did not show anticonvulsant activity.  相似文献   
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