The effects of electrode configuration and click polarity on brainstem auditory evoked potentials (BAEP) in dogs were investigated to clarify the inconsistent nomenclature for each peak. Four positive peaks (waves 1, 2, 3 and 4) before a deep negative trough and a fifth positive peak (wave 5) following the trough were the basic components of BAEP in dogs, which were easily identified regardless of recording conditions such as electrode configuration and click polarity. Additional peaks tended to be present when a noncephalic reference electrode and/or single-polarity (rarefaction or condensation) click stimuli were used. The Roman nomenclature for the individual positive peaks of BAEP in dogs is confused owing to variations in the observed waveforms among researchers, but click polarity and/or reference electrode position can explain all the previously reported variations in BAEP waveforms in dogs. When the criteria concerning wave V in the guidelines of BAEP in human beings are applied to avoid further confusion of Roman nomenclature in dogs, it is recommended that the basic five positive peaks (waves 1, 2, 3, 4 and 5 as identified easily with Ai-Vertex configuration and alternating clicks) are designated as waves I, II, III, V and VI, respectively. Wave IV (wave 3b) occurs occasionally before wave V in dogs.Abbreviations BAEP
brainstem auditory evoked potentials
- dBHL
dB hearing level
- IPL
interpeak latency
- Ai
the caudodorsal end of the zygomatic arch ipsilateral to the stimulated ear
- Nape
the neck over the spinous process of the fourth cervical vertebra 相似文献
Protein kinase C (PKC) activity was evaluated and the phosphorylation of its endogenous substrates was explored in fatty liver induced by administration of ethionine (an analogue of methionine) to cows in order to assess the relevance of PKC-dependent phosphorylation in the development of fatty liver. PKC activity was decreased in both the cytosolic and the total particulate fractions from fatty livers, compared to the corresponding fractions from control liver. The mode of activation by the PKC cofactors (1-oleoyl-2-acetyl-sn-glycerol, 12-O-tetradecanoylphorbol-13-acetate, phosphatidylserine and Ca2+) was similar in both control and fatty livers, suggesting a quantitative but not a qualitative change in PKC in fatty liver. At least three substrate proteins (34 kDa, 26 kDa and 19 kDa) were found in the cytosolic fraction and their phosphorylation was reduced in fatty liver. These results suggest that impairment of the signal transduction pathway mediated by PKC is involved in the pathogenesis of fatty liver in cows.Abbreviations ATP
adenosine triphosphate
- EGTA
ethylene glycol bis(-aminoethylether)-N,N,N,N-tetraacetic acid
- NEFA
non-esterified fatty acid
- OAG
1-oleoyl-2-acetyl-sn-glycerol
- PKC
protein kinase C
- PS
phosphatidylserine
- SDS-PAGE
sodium dodecyl sulphate-polyacrylamide gel electrophoresis
- TG
triglyceride
- TPA
12-O-tetradecanoylphorbol-13-acetate 相似文献
Goats infected with caprine arthritis-encephalitis virus (CAEV) show chronic arthritis and cachexia, which are progressive in nature. The immunopathogenic mechanisms responsible for these progressive clinical symptoms have not been fully elucidated. Various haematological and immunological parameters were evaluated in experimentally-infected goats showing typical signs of CAEV-induced disease. Infected goats showed recurrent lymphocytosis that may be due to constant presentation of antigen by infected cells of a monocyte/macrophage lineage. The serum alkaline phosphatase and -glutamyl transferase concentrations were elevated in infected goats, a characteristic of hepatic and bone disorders. All other serum chemistry parameters were similar between infected and control goats. Importantly, the serum tumour necrosis factor- (TNF-) levels were higher in infected goats. The cachexia seen in infected goats may be at least partly due to altered metabolism as a result of prolonged elevation of serum TNF- levels. Depressed natural killer cell activity was observed in infected goats and may contribute towards the establishment of a persistent infection with CAEV.Abbreviations AIDS
acquired immunodeficiency syndrome
- CAEV
caprine arthritis-encephalitis virus
- GGT
-glutamyl transferase
- HBSS
Hanks' balanced salt solution
- HIV
human immunodeficiency virus
- NK
natural killer
- PBMC
peripheral blood mononuclear cells
- PCR
polymerase chain reaction
- SAP
serum alkaline phosphatase
- TNF
tumour necrosis factor 相似文献
1. The amino acid requirements of laying type pullets during the growing period can be estimated by measuring the growth of different components of the body and making use of nutritional constants that define the amount of each amino acid that is required for the production of the tissues being formed.
2. In this experiment, carcase analyses of each of three breeds of pullets were conducted at weekly intervals throughout the growth of the pullets, to 18 weeks of age. Measurements were made of body weight, gut‐fill and feather weight, and chemical analyses consisted of water, protein, lipid and ash measurements of both the body and the feathers. Each age group comprised 10 birds of each breed.
3. Gompertz functions accurately estimated the growth of both body protein and feather protein, to 18 weeks of age, from which the rate of growth of these two components of the body could be estimated. The mature weight of pullets was overestimated by the Gompertz growth curve, which may indicate that a pullet ceases to increase in body protein content once sexual maturity has been reached.
4. Using allometric relationships between the chemical components of the body and of feathers, all the components of growth could be estimated from the growth of body protein and feather protein. These components were then added together to determine the growth rate of the body as a whole.
5. The daily amino acid requirements for 4 functions were calculated, namely, those for the maintenance of body protein and feather protein, and for the gain in body protein and feather protein. These requirements were then summed to determine the requirement of pullets on each day of the growing period.
6. Using the ‘effective energy’ system, the amount of energy required by these pullets was calculated for each day of the growing period, from which the desired daily food intake of the pullets could be predicted. By dividing the amino acid requirement by this daily food intake it was possible to determine the concentration of amino acids that would be needed in the diet in order to meet the requirements of a pullet.
7. The results indicate that the ratio between the requirement for lysine and for methionine and cysteine changes dramatically during the growing period, negating the concept of a fixed ratio between all the amino acids during growth.
8. The above process is the first step in determining the optimal feeding programme for a population of pullets of a given genotype. The constraining effects, of the diet being offered and of the environment in which the pullets are housed, on the food intake and growth rate of each pullet have to be estimated, and such a theory can then be expanded to include all the individuals in the population. Only by the use: of simulation models can all these constraining effects be considered simultaneously. 相似文献
Azostix-reagent-tests(R) strips (Ames, Miles, Inc., Diagnostic Division, Elkhart, IN) were used to measure blood urea nitrogen values in blood samples from 125 dogs and cats at the North Carolina State University, College of Veterinary Medicine. Results of the tests were compared with standard serum urea nitrogen results. Sensitivity, specificity, and negative predictive values were high (86.4, 90.3, and 96.5%, respectively). Positive predictive value was low, 65.5% of the dogs and cats with elevated blood urea nitrogen values were correctly classified as abnormal The test performs well when the prevalence of abnormal values is near 50%. 相似文献
Varying terms and criteria have been used in the veterinary literature to characterize milky opaque pleural effusions through the years. This article addresses ideas widely repeated in the veterinary and human literature upon which time, experience, diagnostic techniques, experimental data, and improved understanding of pathogenesis have cast doubt. Topics discussed include terminology, pathogenesis of chylous and pseudochylous effusions, criteria for differentiation of chylous from pseudochylous effusions, and clinicopathologic changes associated with drainage of chylous effusions. 相似文献
1. Turkey eggs were incubated at 36.5, 37.5 and 38.5°C. The age of mortality, the incidence of malpositions and the incidence of morphological abnormalities were recorded from all unhatched eggs.
2. Eggs incubated at 36.5°C hatched later than eggs incubated at 37.5°C but did not differ in age of mortality or incidence of malpositions and abnormalities.
3. Eggs incubated at 38.5°C hatched significantly less well than eggs incubated at 37.5°C and showed significant differences in time of embryo mortality. Overheated embryos had a mortality peak between 15 and 20 d of incubation and an increased mortality after 24 d of incubation.
4. Overheated eggs were characterised by a high incidence of embryos with head in small end, with excess albumen, ruptured yolk sacs, oedematous heads, eye cataracts and swollen down‐plumules. 相似文献