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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
1. Male broiler chickens were killed at various times up to 36 h after withdrawal of food; hepatic and muscle glycogen concentrations and pH were compared with those of control birds given continuous access to food and water. 2. Liver glycogen was reduced to negligible concentrations (less than 1 mg/g) within 6 h of food deprivation and the initial pH was elevated. 3. Withdrawal of food had no effect on glycogen concentrations in the m. pectoralis superficialis (PS) but reduced them in the m. biceps femoris (BF); the reduction was significant after 12 h. Ultimate pH was elevated by fasting in the BF, but not the PS. 相似文献
932.
M Sanders-Shamis A A Gabel 《Journal of the American Veterinary Medical Association》1988,193(1):80-82
An avulsed carpal medial collateral ligament was diagnosed by clinical and radiographic examination in a 1-day-old foal that was unable to bear weight on the affected limb. The foal had a valgus deviation originating at the carpus and medial to lateral instability of the affected carpus. The ligament was reconstructed with screws and suture tape. Surgical reconstruction is a viable alternative to long-term casting or splinting for treatment of a ruptured carpal medial collateral ligament in a foal. 相似文献
933.
A monoclonal antibody specific for the T1 tegumental antigen of Fasciola hepatica was used as a solid-phase immunosorbent for the purification of T1 antigen from homogenised mature F hepatica. Material fractionated by this technique was successfully used in enzyme-linked immunoassays to detect antibodies to F hepatica in sera from sheep and cattle. Species differences in response to infection by F hepatica were demonstrated. 相似文献
934.
F J Derksen N E Robinson J S Scott J A Stick 《American journal of veterinary research》1988,49(6):933-938
Ponies with recurrent airway obstruction (principal ponies) and their controls were given aerosolized Micropolyspora faeni antigen via endotracheal tube during a period when the principal ponies were in disease remission. In both groups of ponies, we performed bronchoalveolar lavage (BAL) and measured pulmonary function at base line, and 5 hours after aerosol administration of 30 ml of 0.9% NaCl solution or 30 ml of 1% w/v particulate M faeni antigen in 0.9% NaCl solution. In both groups of ponies, aerosolized M faeni antigen increased WBC count, neutrophil numbers, and albumin concentration in BAL fluid, but macrophage numbers decreased. In the principal ponies, BAL mast cell numbers were decreased 5 hours after administration of M faeni antigen. The M faeni antigen had no effect on the mechanical properties of the lungs or on gas exchange in the control ponies, but did increase respiratory frequency minute ventilation and pulmonary resistance, and decreased arterial oxygen tension in the principal ponies. Changes in pulmonary function were apparent only in the principal ponies, which suggests that neutrophils, per se, do not cause pulmonary dysfunction and that M faeni may be one of the etiologic agents involved in chronic obstructive pulmonary disease. 相似文献
935.
Haematological and blood biochemical changes were studied in nine camels after maximal exercise over 4 or 5 km. There was a lack of splenic reserve for red blood cells, indicated by a minimal increase in haemoglobin concentration and haematocrit. There were marked increases in plasma lactate (to over 20 mmol/litre), plasma ammonia and plasma glucose and a pronounced decrease in circulating free fatty acids. There were small but significant increases in plasma calcium, magnesium, sodium, potassium, chloride and phosphate concentrations. 相似文献
936.
Four asexual generations of Eimeria mitis were identified. The first three developed above the epithelial cell nuclei, but the fourth developed above and below. Meronts measured 13.8 x 16.4 microns, 16.1 x 16.4 microns, 12.1 x 14.6 microns, and 9.5 x 12.4 microns, respectively, of generations 1, 2, 3, and 4. They matured at 36, 67, 72, and 88 hr postinoculation (PI) and contain 20-24, 16-20, 10-14, and 7-10 merozoites, respectively. Merozonts measured 7.2 x 1.9 microns, 8.5 x 2.5 microns, 9.6 x 2.0 microns, and 6.75 x 2.75 microns, respectively. The first two types of meronts were deep in the crypts and epithelial cells. The third and fourth types of meronts were along the side and tip of the villi. Gametocytes developed from third and fourth generation. Gamonts were usually below the nuclei of the epithelial cells. Parasitism was primarily in the ileum, ceca, and rectum and also in the yolk-sac diverticulum. 相似文献
937.
Immune exclusion of Haemonchus contortus larvae in sheep: dose dependency, steroid sensitivity and persistence of the response 总被引:2,自引:0,他引:2
F Jackson H R Miller G F Newlands S E Wright L A Hay 《Research in veterinary science》1988,44(3):320-323
Naive and immune sheep, treated with anthelmintic, challenged directly into the abomasum and killed 48 hours later were used to examine the steroid sensitivity, persistence and dose dependency of immune mechanisms which result in the failure of incoming Haemonchus contortus larvae to establish (immune exclusion). Immune exclusion was almost totally abolished by corticosteroid treatment, the mean percentage of larvae establishing in the mucosa of immune sheep was 1.4 per cent of the challenge infection whereas in those treated with dexamethasone it was 24.4 per cent and in naive sheep 27.3 per cent. Immune animals challenged after seven and 42 days without antigenic experience excluded more than 90 per cent of the challenge larvae from their mucosae, whereas those challenged after 84 days without antigenic experience were as susceptible as naive animals. Immune exclusion was dose dependent, animals challenged with 10(6) and 10(5) larvae excluded 93 per cent and 82.5 per cent of the challenge dose whereas those challenged with 10(4) larvae failed to exclude larvae. 相似文献
938.
939.
In a litter of seven three-week-old English cocker spaniels, four showed persistent pupillary membrane and congenital cataract. One affected male and two affected females were kept for breeding purposes. Brother/sister mating gave birth to 14 pups. Two pups died the first day. The other 12 were euthanased at an age of one year. None of them showed any sign of eye diseases either by clinical or histological examination. The parents, one male and two females, were euthanased at the age of 20, 24 and 33 months, respectively. Clinical and histological examination of the eyes showed varying degree of loss of vision, persistent pupillary membranes, microphthalmos and cataract. 相似文献
940.
DOUGLAS ALLEN Jr . dvm ms Diplomateacvs NATHANIEL A. WHITE II dvm ms Diplomateacvs DAVID E. TYLER dvm PhD Diplomateacvp 《Veterinary surgery : VS》1988,17(1):10-14
The morphologic effects of induced intraluminal hydrostatic pressures (IHPs) of 0, 9, and 18 cm H2 O were evaluated in 33 isolated equine jejunal segments. Fifteen segments were distended with Tyrode's solution for 1 hour and nine segments for 4 hours. Tyrode's solution was added as needed to maintain the prescribed pressures. Nine other segments were left undisturbed for 4 hours after the initial distention period. On decompression of the intestinal segments, progressive peristaltic contractions resumed in all segments. Evaluation of intestinal sections by light microscopy and transmission electron microscopy showed edema of the villi and submucosa and separation of the epithelial cells adjacent to the basement membrane in all segments. The epithelial cell necrosis found in ischemic intestine was not seen. This study indicates that the necrosis found at the villous tips in distended sections of small intestine remote from the site of obstruction cannot be reproduced by IHP increases of 4 hours duration. 相似文献