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961.
Pigs weaned for five days had caecal contents with significantly lower osmolalities than those of unweaned animals of the same age. Supplementation of a standard weaning diet with therapeutic levels of oxytetracycline to suppress the normal large intestinal microbial flora did not significantly further reduce osmolarity of caecal contents after weaning. This observation suggests that microbial activity in the large intestine may not be sufficiently developed by five days after weaning to have a major influence on absorptive processes at that site. Incomplete development of the large intestinal microflora may be one more factor which acts to predispose the young pig to diarrhoea after weaning.  相似文献   
962.
Dyserythropoiesis characterized by enhanced intramedullary destruction, pathologic sideroblasts and siderocytes, and hemoglobin crystallization was detected in a female Cocker Spaniel presented for poor exercise tolerance. Examination of peripheral blood revealed intraerythrocytic crystals, granulation of erythrocytes, nucleated erythroid cells, reticulocytosis and marked variation in erythrocyte morphology in the absence of anemia. Bone marrow examination revealed sideroblasts, a low M:E ratio and evidence of enhanced intramedullary destruction of erythroid cells. Electron microscopy of peripheral blood and bone marrow confirmed pathologic mitochondrial iron accumulation in erythroid cells and the presence of intraerythrocytic hemoglobin crystals. A cause for the hematologic changes was not identified. After the animal became clinically normal, siderocytes disappeared from peripheral blood but intraerythrocytic crystals and reticulocytosis persisted.  相似文献   
963.
Hookworm infected dogs had higher blood basophil counts than hookworm negative dogs. Dogs with occult heartworm infection (i.e., without microfilaremia) had higher blood neutrophil counts than heartworm negative dogs. The percentage of eosinophils in peripheral lymph nodes was higher in heartworm infected, microfilaremic dogs than in both occult infected dogs and heartworm negative dogs. Heartworm or intestinal parasitic infection had no other significant effects on hematologic parameters or peripheral lymph node cytology.  相似文献   
964.
Prednisone was give norally(2mg/kg b.i.d.) to seven healthy mixed breed dogs for 3 consecutive days. Serum iron concentration increased significantly (p < 0.05) from 142 +/- 26 micro g/dl (mean +/- SE) before a drug adminis- tration on Day 0 to a maximum of 307 +/- 47 micro g/dl on Day 2, and returned to the Day 0 value by Day 5. Mean total iron binding capacity did not vary more than 25% from the Day 0 value during the 9 day long study. The percent saturation of transferrin with iron increased from 33 +/- 6% on Day 0 to a maximum of 71 +/- 9% on Day 3. This determination had decreased to 34 +/- 3% on Day 5. No statistically significant changes occurred in these parameters studied in six control dogs that were not given the drug. To determine whether serum iron concentration might be correlated with endogenous serum cortisol concentration, these tests were determined in serum collected from nine dogs at 7 a.m., 3 p.m., and 11 p.m. each day for 3 consecutive days. Serum iron concentration was lower at 7 a.m. (147 +/- 9 micro g/dl) than at 3 p.m. (164 +/- 9 micro g/dl) or 11 p.m. (159 +/- 10 micro g/dl). Likewise serum cortisol was lower at 7 a.m. (1.29 +/- 0.18 micro g/dl) than at 3 p.m. (1.49 +/- 0.19 micro g/dl) or 11 p.m. (1.51 +/- 0.22 micro g/dl). There was a significant positive linear correlation between serum iron and serum cortisol concentrations when they were compared using mean values for each dog. From these studies, it appears that exogenously administered glucocorticoids and endogenous increases in serum cortisol concentrations may result in increased serum iron concentrations in dogs.  相似文献   
965.
A new technique by High Performance Liquid Chromatography (HPLC-gel permeation) shows promise as a tool to separate and quantitate the Unsaturated Vitamin B(12) Binding Capacity (UBSC) of the individual Vitamin B(12) binders in blood serum. This method, although not as rapid as protein-coated charcoal or cellulose separation techniques, is more applicable for use with large numbers of samples than gel filtration. The use of a radioactivity detector to monitor the eluant from the column permitted automation of the method. Comparable results for UBBC and for the UBBC of individual binders were obtained when samples were analyzed by gel filtration and HPLC. The HPLC method proved suitably precise and the recovery of added cyanocobalamin was acceptable. It is proposed that HPLC be the method of choice for measurement of the USBC of binders of Vitamin B(12) in blood serum.  相似文献   
966.
Latissimus dorsi and cutaneous trunci myocutaneous flaps of equal dimension and location were randomly elevated on opposite sides of the thorax in 10 dogs (group 1) and resutured to their respective bed. The procedure was repeated in four additional dogs (group 2); however, the short perforating branches of the thoracodorsal artery and vein were divided at the base of each cutaneous trunci myocutaneous flap, whereas the cutaneous pedicle and underlying cutaneous trunci muscle were divided in the latissimus dorsi myocutaneous flaps to determine subsequent skin survivability and the major source of circulation of each myocutaneous flap. There was little difference in the percentage of skin survival between the latissimus dorsi and cutaneous trunci myocutaneous flaps in group 1 dogs. Circulation to the "skin island" of group 2 latissimus dorsi myocutaneous flaps originated from intramuscular anastomotic connections between the major branch of the thoracodorsal artery entering the latissimus dorsi muscle and the proximal lateral intercostal arteries perforating the muscle. Ligation of the short perforating branches of the thoracodorsal artery resulted in partial skin necrosis in all group 2 cutaneous trunci myocutaneous flaps. Results from this study indicate that it is unnecessary to elevate the latissimus dorsi muscle for major skin flap elevation and survival. The thicker latissimus dorsi myocutaneous flap is more difficult to develop surgically and appears to have no clinical major advantage over the more mobile cutaneous trunci myocutaneous flap or the adjacent thoracodorsal axial pattern flap for closure of large skin defects within the radius of flap rotation.  相似文献   
967.
With electromyography and strain gauges the uterine motility of the sow during the oestrous cycle and early pregnancy was studied. Special attention was paid to characterization of myometrial activity at the time of intrauterine migration of blastocysts.From recordings of 4 animals (3 became pregnant) 3 types of electrical spiking activity (each could be correlated with an elevation of the strain gauge tension) were discerned. Two of them appeared regularly and were suitable for analysis: High Voltage Slow Acticity (with relative high amplitude and low frequency of spikes) and Low Voltage Fast Activity (with relative low aplitude and high frequency of spikes).The sexual status markedly influenced myometrial activity: during prooestrus and oestrus only one type of electrical activity was present whereas the myoelectrical complex (an episode of this activity and the subsequent interval of inactivity) was shorter than 10 min. During dioestrus the myoelectrical complex was longer than 10 min and High Voltage Slow Activity (solely on the cervix and bifurcation) and Low Voltage Fast Activity occurred simultaneously in episodes which mainly appeared to originate on the bifurcation.The characteristics of uterine activity during pregnancy were similar to those of a cyclic sow until day 12. It was only on day 12 that gestation appeared from an increased frequency of myoelectrical complexes.It is concluded that Low Voltage Fast Activity as it was found on the uterine horn at days 8–9 might be involved in the process of intra-uterine migration of blastocysts. In cyclic and in pregnant animals the patterns of Low Voltage Fast Activity were similar. Therefore, the occurrence of Low Voltage Fast Activity is independent of the actual presence of blastocysts. It seems to be exhibited in dependence on the ovarian hormones.  相似文献   
968.
Treatment of greenhouse-grown eggplant (Solanum melongena L. var. esculentum Nees. 'Burpee's Black Beauty') seedlings with supplemental photosynthetically active radiation from cool-white fluorescent lamps increased growth of plants subsequently transferred outdoors relative to growth of plants that received no supplemental radiation or were shaded to 45% of solar irradiation in the greenhouse before transfer outdoors. Eggplant seedlings transferred outdoors were placed under plastic tarps either to provide relative protection from solar ultraviolet-B (UV-B) radiation (280-315 nm) using Mylar film or to allow exposure to UV-B using cellulose acetate. Protection of seedlings from UV-B radiation resulted in greater leaf expansion than for UV-B-exposed seedlings, but no change in leaf or shoot dry weight occurred after 9 days of treatment. Specific leaf weight increased in response to UV-B exposure outdoors. Exposure of eggplant to UV-B radiation from fluorescent sunlamps in the greenhouse also decreased leaf expansion and leaf and shoot dry weight gain after 5 days of treatment. However, there were no differences in leaf or shoot dry weight relative to control plants after 12 days of UV-B treatment, indicating that UV-B treated plants had acclimated to the treatment and actually had caught up with non-UV-B-irradiated plants in terms of growth.  相似文献   
969.
The computer-assisted, kinetics-based enzyme-linked immunosorbent assay for coronavirus antibodies in cats was calibrated to the conventional indirect immunofluorescence assay by linear regression analysis and computerized interpolation (generation of "immunofluorescence assay-equivalent" titers). Procedures were developed for normalization and standardization of kinetics-based enzyme-linked immunosorbent assay results through incorporation of five different control sera of predetermined ("expected") titer in daily runs. When used with such sera and with computer assistance, the kinetics-based enzyme-linked immunosorbent assay minimized both within-run and between-run variability while allowing also for efficient data reduction and statistical analysis and reporting of results.  相似文献   
970.
Meat tins denoted as pork in natural juice, beef with bacon, luncheon meat and liver paté, all produced in a food-processing plant, were stored under definite conditions (temperature 21 degrees C, relative humidity 73%) for three years. Before the long-term storage and then in half-year intervals, the contents of the residues of chlorinated pesticides, including HCB (hexachlorobenzene), gamma-HCH (gamma isomer of hexachlorocyclohexane) and pp'DDE (1,1-dichloro-2,2-bis/p-chlorofenyl/-ethylene), were determined in the above-mentioned final products by the method of gas chromatography. As suggested by the records of the changes in the pesticide residue contents in the meat tins during their long-term storage, the average contents of all chlorinated carbohydrates gradually decrease with the length of storage and the "reduction" of residues varies with the kind of final product and with the pesticides. In HCB the reduction ranged from 18.4 to 34.4%, in gamma-HCH from 36.2 to 80.4% and in pp'DDE from 23.9 to 48.9%.  相似文献   
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