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21.
Glenn S. Peterson Mohamed A. Kandil Mounir D. Abdallah Abdel-aal A. Farag 《Pest management science》1989,25(4):337-342
Of the numerous fractions obtained from the crude plant extracts of Chenopodium ambrosioides, Conyza dioscordisis and Convolvulus arvensis, 11 were found to be active against stored grain pests. The chemical structures of compounds present in the 11 fractions were found by gas chromatography/mass spectrometry to include predominantly long-chain fatty acid esters of hexadecanoic, arachidonic, and octadecanoic acids. 相似文献
22.
Approaches to pathogen-mediated resistance breeding against plum pox potyvirus in stone-fruit trees1
A. DA CMARA MACHADO E. KNAPP H. PÜHRINGER G. SEIFERT V. HANZER H. WEISS H. KATINGER M. LAIMER DA CMARA MACHADO 《EPPO Bulletin》1994,24(3):697-704
In a programme for developing systems which allow the transfer of foreign genes into apricot cultivars, we have tested cotyledons of immature embryos, somatic embryos and leaf discs. Apricot plants have been transformed, and then regenerated, with Agrobacterium tumefaciens strain LBA 4404 containing various binary plasmids: pBinGUSint, carrying the marker gene β-glucuronidase (GUS), and pBinPPVm, carrying the coat-protein gene of plum pox potyvirus (PPV). The marker gene GUS was used for visual evaluation of the efficiency of the transformation system. The coat-protein gene was used in the hope of introducing coat protein-mediated resistance to one of the most important stone-fruit pathogens in Europe and the Mediterranean area. 相似文献
23.
Serum total thyroxine, total triiodothyronine, free thyroxine, and thyrotropin concentrations in dogs with nonthyroidal disease 总被引:5,自引:0,他引:5
Kantrowitz LB Peterson ME Melián C Nichols R 《Journal of the American Veterinary Medical Association》2001,219(6):765-769
OBJECTIVE: To determine whether nonthyroidal disease of various causes and severity is associated with abnormalities in baseline serum concentrations of total thyroxine (T4), triiodothyronine (T3), free T4, or thyrotropin (thyroid-stimulating hormone [TSH]) in dogs believed to be euthyroid. DESIGN: Case-control study. ANIMALS: 223 dogs with confirmed nonthyroidal diseases and presumptive normal thyroid function, and 150 clinically normal dogs. PROCEDURE: Serum total T4, total T3, free T4, and TSH concentrations were measured in dogs with confirmed nonthyroidal disease. Reference ranges for hormone concentrations were established on the basis of results from 150 clinically normal dogs. RESULTS: In dogs with nonthyroidal disease, median serum concentrations of total T4, total T3, and free T4 were significantly lower than those in clinically normal dogs. Median serum TSH concentration in sick dogs was significantly greater than that of clinically normal dogs. When stratified by severity of disease (ie, mild, moderate, and severe), dogs with severe disease had low serum concentrations of total T4, total T3, or free T4 more commonly than did dogs with mild disease. In contrast, serum TSH concentrations were more likely to remain within the reference range regardless of severity of disease. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that serum total T4, free T4, and total T3 concentrations may be low (ie, in the hypothyroid range) in dogs with moderate to severe nonthyroidal disease. Serum TSH concentrations are more likely to remain within the reference range in sick dogs. 相似文献
24.
Moore GE Burkman KD Carter MN Peterson MR 《Journal of the American Veterinary Medical Association》2001,219(2):209-214
OBJECTIVE: To determine causes of death or reasons for euthanasia in a population of military working dogs. DESIGN: Retrospective study. ANIMALS: 927 military working dogs. PROCEDURE: Records of all military working dogs that died during the period from 1993 to 1996 were evaluated for cause of death or reason for euthanasia by review of necropsy and histopathology reports, death certificates, and daily clinical treatment sheets. A single primary cause of death or euthanasia was determined. RESULTS: Although sexually intact male dogs were more numerous in the study population, castrated male dogs typically lived longer than spayed females or sexually intact males. Leading causes of death or euthanasia (76.3% of all dogs) were appendicular degenerative joint disease, neoplasia, spinal cord disease, nonspecific geriatric decline, and gastric dilatation-volvulus. Compared with German Shepherd Dogs, Belgian Shepherd Dogs were at increased risk for death attributable to neoplasia, behavior, and respiratory tract disease. German Shepherd Dogs had nearly twice the risk for death associated with spinal cord diseases, compared with Belgian Shepherd Dogs. CONCLUSIONS AND CLINICAL RELEVANCE: For most military working dogs, death or euthanasia results from a few diseases commonly associated with advanced age. Some breed differences in risk for these diseases may exist, which clinicians should consider in the procurement and long-term management of these dogs. 相似文献
25.
OBJECTIVE: To identify factors regulating secretion of alpha-melanocyte-stimulating hormone (alpha-MSH) from the pars intermedia (PI) of the pituitary gland of cats. ANIMALS: 28 healthy adult cats. PROCEDURE: Indwelling catheters were placed in 1 jugular vein of each of 7 to 10 cats, depending on treatment group. Sixteen hours later, 3 blood samples were collected for determination of baseline plasma hormone concentrations, and saline solution or a test substance (haloperidol, corticotropin-releasing hormone, bromocriptine, isoproterenol, insulin, or dexamethasone) was administered via the catheter. Subsequent blood samples were collected at regular intervals for up to 240 minutes after injection. Concentrations of ACTH, cortisol, and alpha-MSH were measured in plasma by use of specific radioimmunoassays. Cats were rested for at least 3 weeks between experiments. RESULTS: Administration of haloperidol and isoproterenol resulted in increased, and bromocriptine and insulin in decreased, circulating concentrations of alpha-MSH from baseline. ACTH and plasma cortisol concentrations increased after administration of all test substances except dexamethasone. Dexamethasone injection resulted in decreased plasma concentrations of ACTH and cortisol. CONCLUSIONS: Secretion of alpha-MSH from the PI of cats appears to be inhibited by dopaminergic activity and stimulated by beta-adrenergic influences. Activation of secretion of alpha-MSH from the PI can be dissociated from activation of secretion of other pro-opiomelanocortin-derived peptides, such as ACTH, arising from the pars distalis. Regulation of secretory activity of the PI of cats resembles that of rats. 相似文献
26.
Pituitary-dependent hyperadrenocorticism in a cat 总被引:1,自引:0,他引:1
Pituitary-dependent hyperadrenocorticism was diagnosed in a 9-year-old, male castrated cat that had polyuria, polyphagia, pendulous abdomen, truncal hair loss, congestive heart failure, and insulin-resistant diabetes mellitus. Results of pituitary-adrenal function testing revealed inadequate serum cortisol suppression following dexamethasone administration, exaggerated serum cortisol responses after exogenous ACTH stimulation, and high plasma ACTH concentrations. The pathologic findings of bilateral adrenocortical hyperplasia and a pituitary adenoma that immunostained well for ACTH-related peptides confirmed pituitary-dependent hyperadrenocorticism. 相似文献
27.
Mary M. Christopher John D. Broussard Mark E. Peterson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(1):24-31
Oxidative damage plays an important role in the pathophysiology of diabetes and diabetic complications. Feline hemoglobin is uniquely susceptible to oxidative denaturation; therefore, Heinz body formation is a highly sensitive indicator of in vivo oxidative stress in this species. Heinz bodies also contribute to anemia. We investigated hematological and clinical biochemical changes in 30 cats with spontaneous diabetes mellitus (as compared to 15 healthy control cats) and evaluated the relationship of these changes to erythrocyte oxidative damage. Cats were categorized as ketoacidotic or nonketoacidotic based on their clinical presentation and the presence of urine ketones. Ketoacidotic cats had significantly ( P = .0009) more Heinz bodies (28.3% ± 9.1 %) than nonketotic diabetic cats (6.5% ± 1.60%) and healthy control cats (0.6% ± 0.2%). Percent Heinz bodies in diabetic cats directly correlated with plasma β-hydroxy-butyrate concentration ( r = .622; P = .0002), as well as with serum chloride concentration ( r = -0.576; P = 0.0009) and the number of monocytes ( r = .536; P = .0023). Percent Heinz bodies were negatively correlated with erythrocyte glutathione concentrations. Erythrocyte membrane lipid peroxidation was slightly but not significantly increased in diabetic cats. There were no significant associations between percent Heinz bodies and degree of anemia, hyperglycemia, or glycohemoglobin. These data indicate that ketones are associated with oxidative hemoglobin damage in cats, and suggest that ketone metabolism, ie by cytochrome P450 2E1, may be a potential source of in vivo oxygen radical generation in animals with ketosis. 相似文献
28.
29.
Fetal fluid, diaphragm muscle, heart, kidney, and liver from 14 four- to five-month-old calf fetuses were analyzed for Zn, Cu, Cd, Cr, Ni, Pb, and Fe. The same tissues and bone were examined from postparturient calves 30, 60, and 120 days of age. Weaned calves (8 to 9 months old) were necropsied and diaphragm muscle, heart, kidney, liver, brain, and bone were analyzed. Additional calves from cows exposed or not exposed to anaerobically digested sludge were placed in a feed yard at weaning for a feeding period of 150 days and then were killed and necropsied. Heavy metal content of the aforementioned tissues was compared with the same tissues obtained from peer calves weaned, killed, and necropsied 150 days earlier. Zinc, Cu, and Fe were up to 11 times higher in fetal livers than in control or exposed postparturient calves. These concentrations declined after birth and stabilized at approximately the concentrations observed in adult cattle at about 12 to 14 months of age. Cadmium accumulated to a greater extent in kidneys and livers of exposed calves than in control calves. However, the accumulation did not produce a detectable effect upon the functional or morphologic characteristics of the organs examined. Other metals were present at low levels and were generally not remarkably different in control and exposed animals. 相似文献
30.
C E Leifer M E Peterson R E Matus A K Patnaik 《Journal of the American Veterinary Medical Association》1985,186(1):53-55
Hypoglycemia associated with nonislet cell tumor was found in 13 dogs. In each dog, clinical signs were related directly to adrenergic and neuroglucopenic effects of hypoglycemia and included collapsing episodes, tremors, restlessness, weakness, and grand mal seizures that were responsive to glucose administration. Eight of the dogs had hepatocellular carcinoma; surgical resection of the tumor achieved remission of clinical signs in 3 of these dogs. Other hepatic tumors associated with hypoglycemia included leiomyosarcoma and hemangiosarcoma involving solitary lobes of the liver. Nonhepatic tumors included splenic hemangiosarcoma, diffuse metastatic melanoma, and salivary gland adenocarcinoma. 相似文献