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901.
40 in-calf heifers were observed to examine the effect of timbers placing in passage area on their use of cubicle beds. Prior to the experiment preliminary observation was taken on these 40 heifers and they were divided into two even groups (cubicle user(or control) group versus cubicle refusal (or experimental) group by whether they properly used the cubicle beds or not. The timbers were placed in passage and feeding areas for the cubicle refusal group to force the animls to lie in the cubicle beds. The results of this experiment showed that feeding behaviour was unaffected by the presence of the timbers, but lying acitvity was about 8% higher for the experimental group, which led to a mean of almost 2 hours longer lying time over 24 h. After the timbers were removed, there was a significant decline in lying by the experimental group. The diurnal pattern of lying behaviour in cubicles indicated that the major effect on lying activity exerted by the presence of the timbers was seen during midnight to 10:00 a  相似文献   
902.
The discriminating ability of 15 parameters alone or in combinations, including results from analysis of plasma endotoxin, the Nycomed plasma D-Dimer test and phospholipase A2, were analyzed to predict morbidity and mortality in equine gastrointestinal colic. Endotoxaemia was a characteristic feature of the colic horses. The problem of adequately predicting non-survivors among colic horses required several parameters to be included in the logistic model: if the “classical parameters”, (heart rate, respiratory rate, PCV, anion gap) were included in the model, addition of plasma D-dimer, phospholipase A2, and Cl- significantly improved the predictive value of the logistic model. Increasing heart rate and D-dimer together with decreasing chloride was a risk factor for nonsurvival. The sensitivity of this three-parameter logistic model to predict nonsurvival was 78% and specificity 77%. The Nycomed D-Dimer test is recommended as a horse-site test to predict disseminated intravascular coagulation and nonsurvival in equine colic.  相似文献   
903.
The effectiveness of the morantel sustained release trilaminate (MSRT) in controlling gastrointestinal nematodes through a grazing season was evaluated using 60 yearling beef stocker calves randomly divided into 2 groups of 30 animals each. In April 1985, the calves comprising the treatment group each received an MSRT designed to release morantel tartrate continuously for 90 days while those of the control group remained unmedicated. All animals were weighed and samples of rectal feces were taken at 14-day intervals, beginning on Day 0, until trial termination (Day 168). At trial termination, 10 control and 10 treated calves were necropsied for recovery of gastrointestinal nematodes. Three sets of parasite-na?ve tracer calves were utilized to evaluate the initial, interim and final levels of pasture contamination by nematode larvae. Overall, the use of the MSRT resulted in a 75.5% reduction (P less than 0.001) in output of nematode eggs from the principals, an 81.8% reduction (P less than 0.001) in numbers of gastrointestinal nematodes in principals (at trial termination), and a 96.9% reduction (P less than 0.05) of pasture larval nematode contamination (as indirectly indicated by parasite burdens in tracer calves). The mean weight advantage of treated calves was 16.6 kg per head (P less than 0.001).  相似文献   
904.
Nine groups of rats (n = 5 per group) received an intramuscular (IM) injection of one of the following drugs or drug combinations: saline, atropine (0.05 mg/kg), glycopyrrolate (0.5 mg/kg), ketamine:xylazine (85:15 mg/kg), ketamine:detomidine (60:10 mg/kg), atropine:ketamine:xylazine (0.05: 85:15 mg/kg), glycopyrrolate: ketamine:xylazine (0.5:85:15 mg/kg), atropine:ketamine:detomidine (0.05: 60:10 mg/kg) or glycopyrrolate: ketamine:detomidine (0.5:60:10). Similarly six groups of rabbits (n = 5) received an IM injection of either saline, atropine (0.2 mg/kg), atropine (2 mg/kg), glycopyrrolate (0.1 mg/kg), ketamine:xylazine (35:10 mg/kg) or glycopyrrolate:ketamine:xylazine (0.1:35:10 mg/kg). In rats, atropine sulfate (0.05 mg/kg) and glycopyrrolate (0.5 mg/kg) produced an increase in heart rate for 30 and 240 min, respectively. In rabbits atropine sulfate at either 0.2 or 2.0 mg/kg did not induce a significant increase in heart rate, but glycopyrrolate (0.1 mg/kg) elevated the heart rate above saline treated animals for over 50 min. Both atropine and glycopyrrolate provided protection against a decrease in heart rate in rats anesthetized with ketamine: xylazine (85:15 mg/kg) or ketamine: detomidine (60:10 mg/kg); however, glycopyrrolate was significantly more effective in maintaining the heart rate within the normal range. Glycopprrolate also prevented a decrease in heart rate in rabbits anesthetized with ketamine:xylazine (35:5 mg/kg). Neither glycopyrrolate nor atropine influenced respiration rate, core body temperature or systolic blood pressure when used alone or when combined with the injectable anesthetic. Glycopyrrolate is an effective anticholinergic agent in rabbits and rodents and more useful as a preanesthetic agent than atropine sulfate in these animals.  相似文献   
905.
SUMMARY Bronchoalveolar lavage (BAL) was performed at weekly intervals in 10 Thoroughbred horses in race training (group 1) and in 4 rested horses (group 2) for 10 weeks. Lavages were continued on a weekly basis in 4 group 1 horses for an additional 9 weeks (group 3). Cytological analysis of samples included leukocyte counts, erythrocyte counts, differential leukocyte counts, and haemosiderophage score. The mean leukocyte concentration was significantly lower in group 1(92.1 ± 4.6 cells/μL) when compared with group 2 (133.5 ± 8.2 cells/μL), P = 0.037. The differential leukocyte data were not significantly different between groups. There was a large amount of variability in the percent-age of macrophages and lymphocytes in the differential counts over time with no obvious trends. The proportion of neutrophils demonstrated a tendency to decrease over time for both groups 1 and 2. Erythrocyte counts and haemosiderin scores were significantly higher in the exercising group than the rested horses. Neither exercise nor the technique itself evoked an inflammatory response in the BAL fluid.  相似文献   
906.
Moderately PSE (pale, soft, exudative) and moderately DFD (dark, firm, dry) pork was examined by x-ray diffraction for interfilament separation, by differential interference contrast microscopy for interfiber area, and was centrifuged to measure water holding capacity (WHC). Internal reflectance spectra were measured by fiber optics. For PSE to DFD pork, filament separation ranged from 39 to 48 nm, interfiber area from 42 to 3%, and WHC from 49 to 64%, respectively. The correlation of reflectance with interfilament separation varied considerably with wavelength (reaching r = -.83 at 680 nm, P less than .005). The correlation of reflectance with interfiber area was more uniform across the spectrum (reaching r = .90 at 450 nm, P less than .005), as was the correlation of reflectance with WHC (reaching r = -.80 at 400 nm, P less than .005). At 24 h postmortem, fiber-optic spectrophotometry may be used as a rapid, nondestructive method to predict WHC and potential fluid losses from commercial pork with a moderate range from PSE to DFD. Interfiber area was correlated negatively with filament lattice area and WHC, but no significant correlation was found between filament lattice area and WHC. Filament separation was decreased only slightly by centrifugation. These results indicate that at 24 h postmortem the extra fluid released from PSE pork already has been lost from the myofilament lattice and is awaiting release from compartments downstream such as interfiber and interfascicular spaces.  相似文献   
907.
We have adapted an enzyme-linked immunoblot assay (ELIBA) for the detection of a c-ras proto-oncogene and oncogene protein products in human cell lines and tumors of 21,000 daltons molecular weight (p21ras) to studies of tissues derived from sheep. In the ELIBA, a double antibody system is used in which p21ras proteins are initially immunoprecipitated from protein extracts with monoclonal antibodies, and subsequently identified using additional anti-ras antibodies. Binding is identified with a non-radioactive enzyme-linked colorimetric detection system. In the present study, the ELIBA system was used to study twenty-seven ovine lung specimens, representing normal lung, inflammatory, and neoplastic lesions. We detected p21ras protein expression in every tissue examined, but the nature and amount of the protein product varied significantly among the tissues examined. Some tissues expressed multiple ras species. Broncho-alveolar carcinoma specimens were most likely to express c-Ki-ras proteins. Mutant proteins of c-N-ras and c-Ki-ras were detected in several bronchoalveolar carcinoma specimens, based on migrational differences between mutant and normal proteins in 15% polyacrylamide gels. The results of this study demonstrate the utility of the ELIBA system for detection of c-ras expression in ovine lung tissues, and demonstrate the ability of the system to discriminate specific ras protein species. The prognostic significance of ras expression in sheep pulmonary carcinoma has yet to be determined.  相似文献   
908.
Germinating seeds and young plants of winter rape var. Górczañski were vernalized for 56–63 days under conditions of 9-hour day, at the temperature 2 and 5 °C and in continuous darkness at the temperature 2 °C. After vernalization the plants grew under conditions enabling to complete vernalization: in a glass-house at the temperature day/night 15/10 °C and in semi natural conditions of open vegetation hall in the period from June till August. After sub-optimal vernalization further growth of the plants at lowered temperature increased its effectiveness (completion of vernalization). Depending on the degree of the vernalization of the plants the completion of their vernalization was both obligatory, i.e. conditioning the acquisition of the ability of generative development, and facultative i.e. accelerating this development. It has been demonstrated that the population of plants of the examined variety is strongly differentiated not only with respect of vernalization requirements in the particular plants, but also what regards the effectiveness of vernalization completion. New observations have been made indicating that the mechanisms controlling the successive phases of generative development, i.e. phase of forming flower buds and the flowering phase are not identical which may be interpreted as indicating that the "flowering factor" is polymorphous.  相似文献   
909.
Ten, anesthetized dogs were instrumented with three pulse oximeter probes; two lingual transmittance probes and one rectal reflective probe. Arterial oxygen desaturation was produced by decreasing the inspired oxygen concentration. Hypotension was produced with an infusion of nitroprusside. Simultaneous pulse oximeter readings (SpO2) were compared to co-oximeter measured arterial saturation (SaO2) collected over a range of SaO2 (50–100%) and mean arterial pressures (40–100mmHg). Each of the monitors and means of evaluating SpO2 studied provided accurate SpO2 measurements over a range of mean arterial pressure from 40–100mmHg. All of the monitors tested tended to overestimate the SaO2 when the arterial saturation was less than 70%.  相似文献   
910.
K. SEMB 《Weed Research》1996,36(4):353-367
As a part of a broader study, two experiments were carried out in growth chambers with three day/night temperature regimes (10/7, 20/14 and 30/21^C) studying growth characteristics of individual seedlings over a four-week period. Experiment 1 was performed with spring barley (Hordeum vulgare L.), Galeopsis tetrahit L., and Viola Arvensis Murray. Experiment 2, with three irradiance levels at 20/14^C, and one irradiance level at the other temperatures, was performed with spring barley, V. arvensis, Chenopodium album L., Brassica rapa L. sspoleifera (DC.) Metzger, and Stellaria media (L.) Vill. Leaf area, dry weight, relative growth rate, net assimilation rate, and net photosynthetic rate generally showed an optimum at 20/14^C. Increasing irradiance resulted in a decreased specific leaf area. Expressed as fraction of shoot dry weight, green leaves decreased and stems, flowers, and yellow leaves increased with increased time, irradiance, and temperature. At all temperatures, barley, B. rapa and G. tetrahit had the largest dry weights, but at 20/14^C. C album and S. media and at 30/21^C C. album also had large values. Differences in dry weight between species correlated more to morphological features than to assimilation rate.  相似文献   
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