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11.
OBJECTIVE: To measure activities of digestive enzymes during postnatal development in dogs. SAMPLE POPULATION: Gastrointestinal tract tissues obtained from 110 Beagles ranging from neonatal to adult dogs. PROCEDURE: Pepsin and lipase activities were measured in gastric contents, and amylase, lipase, trypsin, and chymotrypsin activities were measured in small intestinal contents and pancreatic tissue. Activities of lactase, sucrase, 4 peptidases, and enteropeptidase were assayed in samples of mucosa obtained from 3 regions of the small intestine. RESULTS: Gastric pH was low at all ages. Pepsin was not detected until day 21, and activity increased between day 63 and adulthood. Activities of amylase and lipase in contents of the small intestine and pancreatic tissue were lower during suckling than after weaning. Activities of trypsin and chymotrypsin did not vary among ages for luminal contents, whereas activities associated with pancreatic tissue decreased between birth and adulthood for trypsin but increased for chymotrypsin. Lactase and gamma-glutamyltranspeptidase activities were highest at birth, whereas the activities of sucrase and the 4 peptidases increased after birth. Enteropeptidase was detected only in the proximal region of the small intestine at all ages. CONCLUSIONS AND CLINICAL RELEVANCE: Secretions in the gastrointestinal tract proximal to the duodenum, enzymes in milk, and other digestive mechanisms compensate for low luminal activities of pancreatic enzymes during the perinatal period. Postnatal changes in digestive secretions influence nutrient availability, concentrations of signaling molecules, and activity of antimicrobial compounds that inhibit pathogens. Matching sources of nutrients to digestive abilities will improve the health of dogs during development. 相似文献
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Nöckler K Kutzer P Reif S Rosenberger N Draeger A Bahn P Göllner C Erlbeck C 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):368-372
Brucella (B.) canis was isolated from ejaculate of a 4-year old Korthals-Griffon male dog after occurrence of epididymitis and orchitis. Despite several trials of therapy with different antibiotics relapes occurred, with B. canis being isolated from ejaculate, blood and urine samples, respectively. Bacteriological examinations were added by serological testing over a period of about 1.5 years. During the study SAT serum titre steadily dropped from 1:200 to 1:50. By CFT, B. canis antibodies were detectable at the beginning with a titre of 1:320 and to the end of the study with titres between 1:80 and 1:160. 相似文献
13.
Gene discovery in Eimeria tenella by immunoscreening cDNA expression libraries of sporozoites and schizonts with chicken intestinal antibodies 总被引:4,自引:0,他引:4
Specific antibodies were produced ex vivo from intestinal culture of Eimeria tenella infected chickens. The specificity of these intestinal antibodies was tested against different parasite stages. These antibodies were used to immunoscreen first generation schizont and sporozoite cDNA libraries permitting the identification of new E. tenella antigens. We obtained a total of 119 cDNA clones which were subjected to sequence analysis. The sequences coding for the proteins inducing local immune responses were compared with nucleotide or protein databases and with expressed sequence tags (ESTs) databases. We identified new Eimeria genes coding for heat shock proteins, a ribosomal protein, a pyruvate kinase and a pyridoxine kinase. Specific features of other sequences are discussed. 相似文献
14.
Laura H Waitt Christopher K Cebra Susan J Tornquist Christiane V L?hr 《Journal of veterinary diagnostic investigation》2006,18(4):405-408
A 22-year-old pinto mixed breed mare was admitted for evaluation of severe colic signs and gastric reflux. Multiple nonpainful, variably sized hard masses were palpated in the subcutis over the thorax, abdomen, and hindquarters of the horse. The mare was diagnosed with sterile peritonitis and had systemically high gamma-glutamyltransferase, amylase, and lipase. Three days into treatment she became febrile with signs of persistent and mild abdominal discomfort; euthanasia was elected. Necropsy revealed peripancreatitis, pancreatic fibrosis, abdominal steatitis and panniculitis. Panniculitis associated with peripancreatitis has been described in humans and dogs but not in horses. Pathogenic models for this entity are discussed. 相似文献
15.
Early dexamethasone treatment after implantation of a sciatic-nerve cuff decreases the concentration of substance P in the lumbar spinal cord of rats with neuropathic pain 下载免费PDF全文
Francis Beaudry Christiane Girard Pascal Vachon 《Canadian journal of veterinary research》2007,71(2):90-97
The main purpose of this study was to evaluate the effects of early dexamethasone treatment on pain-related peptides at an early stage in the development of neuropathic pain induced by implantation of a sciatic nerve cuff in Sprague Dawley rats (body weight 250 to 350 g). The rats were tested for touch sensitivity with the use of von Frey filaments before and 3 d after cuff implantation (n = 12) or sham surgery (n = 6). Half of the cuff-implanted rats received dexamethasone, 1 mg/kg intraperitoneally, 1 h after surgery. Spinal cords were collected on the 3rd day after surgery, and the lumbar enlargement was processed for the detection of selected peptides (neurotensin, substance P, cholecystokinin [CCK], vasoactive intestinal peptide, and calcitonin gene-related peptide) by means of liquid chromatography and tandem mass spectrometry. The right sciatic nerve of each rat was collected, fixed, and stained for histopathological evaluation. Except for neurotensin, all the peptides showed an increased concentration with neuropathic pain; however, the differences were significant (P < 0.05) only for substance P and CCK. In the animals treated with dexamethasone, mechanical allodynia was less pronounced (P < 0.01), and only the concentration of substance P was decreased significantly (P < 0.05). Sciatic nerve sections showed a decrease in C (P < 0.01) and Adelta (P < 0.03) fibres with neuropathic pain and a nearly normal percentage of C fibres after dexamethasone treatment. The dexamethasone-treated animals also had less inflammation detectable microscopically at the nerve constriction site compared with cuff-implanted animals that were not treated with dexamethasone. Our results suggest that in the early stages of neuropathic pain induced by an inflammatory process, dexamethasone may be a useful treatment and that substance P plays an important role in pain perception. 相似文献
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Quantitative sandwich ELISA for the determination of tropomyosin from crustaceans in foods 总被引:3,自引:0,他引:3
The ubiquitous muscle protein tropomyosin has been identified as the major shrimp allergen and is suggested to be a cross-reacting allergen. Previously, only a few methods for the detection of tropomyosin in food have been published. A quantitative sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of tropomyosin from crustaceans in foods has been developed and validated. A polyclonal rabbit antitropomyosin capture antibody and the biotinylated conjugate of the same antibody for detection were the basis for the ELISA, which was specific for crustaceans. The ELISA was able to quantitate tropomyosin in various food matrixes, had a detection limit of 1 microg/g, and cross-reacted to some extent with cockroach. Recoveries ranged from 63 to 120%, and the intra and interassay coefficients of variation were <6 and <14%, respectively. 相似文献
20.
Chao Li Cheng Liu Xiaoying Ma Aidong Wang Ruijun Duan Christiane Nawrath Takao Komatsuda Guoxiong Chen 《Breeding Science》2015,65(4):327-332
The cuticle covers the aerial parts of land plants, where it serves many important functions, including water retention. Here, a recessive cuticle mutant, eceriferum-ym (cer-ym), of Hordeum vulgare L. (barley) showed abnormally glossy spikes, sheaths, and leaves. The cer-ym mutant plant detached from its root system was hypersensitive to desiccation treatment compared with wild type plants, and detached leaves of mutant lost 41.8% of their initial weight after 1 h of dehydration under laboratory conditions, while that of the wild type plants lost only 7.1%. Stomata function was not affected by the mutation, but the mutant leaves showed increased cuticular permeability to water, suggesting a defective leaf cuticle, which was confirmed by toluidine blue staining. The mutant leaves showed a substantial reduction in the amounts of the major cutin monomers and a slight increase in the main wax component, suggesting that the enhanced cuticle permeability was a consequence of cutin deficiency. cer-ym was mapped within a 0.8 cM interval between EST marker and AK370363, a pericentromeric region on chromosome 4H. The results indicate that the desiccation sensitivity of cer-ym is caused by a defect in leaf cutin, and that cer-ym is located in a chromosome 4H pericentromeric region. AK251484相似文献