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201.
The biomechanical holding strength and histological characteristics of a laparoscopic stapled gastropexy (LG) adhesion were compared with that of an incisional gastropexy (IG) adhesion. An LG was performed in 14 dogs and an IG was performed in six dogs. During the LG procedure, the abdomen was insufflated with carbon dioxide and three cannulae were placed in the caudal aspect of the right side of the abdomen. A 35 mm laparoscopic stapler was used to staple the gastric antrum to the adjacent right lateral abdominal wall. The IG procedure was performed through a ventral midline celiotomy. A 35 mm IG was made by apposing the gastric antrum to the adjacent right lateral abdominal wall with two continuous rows of suture. Half of each group of dogs was euthanatized at 7 and 30 days after surgery. The mean tensile load to failure at 7 days was 44.86 ± 18.54 N for the LG group and 85.33 ± 23.59 N for the IG group ( P <.05). At 30 days the values were 72.93 ± 18.01 N for the LG group and 71.17 ± 12.11 N for the IG group ( P =.41). The gastropexy adhesions in the 7-day postoperative group contained variable amounts of fibrin, hemorrhage, mononuclear cell inflammation, loose fibrovascular tissue, and mature collagenous connective tissue. Adhesions in the 7-day postoperative group were divided subjectively into three histological subgroups based on the relative amounts of mature connective tissue within the adhesion. The LG and IG adhesions were randomly distributed among these subgroups ( P = 1.0). Adhesions in the 30-day postoperative group contained well-organized fibrous connective tissue. No difference in the amount of connective tissue could be detected histologically in the LG or IG adhesions. Complications with the LG procedure included stomach perforation (2 cases), splenic puncture (2 cases), and subcutaneous emphysema (4 cases).  相似文献   
202.
The hemodynamic and respiratory effects of three doses (9.7, 15.8, and 23.7 mg/kg intravenous [IV]) of a 1:1 combination of tiletamine and zolazepam were studied after isoflurane anesthesia in cats instrumented for the recording of hemodynamic data. Systolic, mean, and diastolic arterial blood pressures were decreased 1 minute after drug administration but then increased above baseline with all three doses. Cardiac output was decreased briefly at 1 minute with the 15.8 and 23.7 mg/kg doses. The rate of development of left ventricular pressure and peripheral vascular resistance decreased at 1 minute but returned to baseline or above by 10 minutes. There were no significant changes in heart rate, central venous pressure, or left ventricular end diastolic pressure. The arterial pH and blood gas measurements reflected the development of respiratory acidosis after administration of 23.7 mg/kg. These results support the conclusions that tiletamine-zolazepam administered intravenously is a useful and comparatively safe anesthetic agent in the cat.  相似文献   
203.
Sumatra disease is highly destructive in most clove-growing areas of Sumatra and in western parts of Java. Symptoms of leaf-fall and twig die-back, starting in the upper branches, and often associated with wilting, lead to tree death in 6–18 months. Normally, only seedlings and young trees survive. Symptoms are usually more severe and disease spread is more rapid at higher elevations. Patterns of jump-spread suggest that the disease agent is carried via an airborne pathway, possibly by insect vectors. Small, Gram-negative, non-motile, rod-shaped bacteria are consistently associated with the disease. Initial attempts to culture the bacteria in vitro did not succeed. The bacteria are confined within xylem vessels and are found throughout diseased trees. Greyish-brown streaks are present in wood of heavily infected tissues which release a bacterial ooze from cut surfaces; in such tissues many of the vessels are occluded by bacteria embedded in a gelatinous matrix. At the time of first above-ground symptoms, bacteria are already well established in roots and the trunk base, from where they appear to spread upwards in newly formed wood into the crown of the tree. Symptoms are thought to result from root dysfunction and mechanical blockage of the vascular system. All known clove varieties appear equally susceptible.  相似文献   
204.
205.
Résumé— Cet article est une revue des antifongiques systémiques communément utilisés. Sont présentés les origines des diverses substances, leur pharmacocinétique, leur mode d'action, leurs effets secondaires et enfin, leurs indications en médecine vétérinaire. [Hill, P.B., Moriello, K.A., Shaw, S.E. A review of systemic antifungal agents (Antifongiques systémiques: une revue).
Abstract— This paper is a review of commonly used systemic antifungal antibiotics. Included is a review of the origins of the drugs, pharmacokinetics, modes of action, adverse effects and clinical uses in veterinary medicine.  相似文献   
206.
Epiglottic augmentation with injectable bovine collagen or an autogenous or allogenous auricular cartilage graft was performed in 12 horses with endoscopically and radiographically normal epiglottises. The grafting procedures were easy to perform and did not cause apparent discomfort. Cartilage graft extrusion or resorption may have occurred, but was not seen by endoscopy and lateral laryngeal radiography. Only collagen implants remained evident endoscopically, as smooth round submucosal bulges ventral to the epiglottic cartilage. Two horses with collagen implants, and all horses with cartilage autografts and allografts, were euthanatized at week 16. One horse with a collagen implant was euthanatized at week 4 and one at week 6. The epiglottis appeared thickened in three horses with collagen implants, two horses with autogenous grafts, and three horses with allogenous grafts. Pharyngeal lymphoid tissue was hyperplastic in two horses with autografts and three horses with allografts, but not in horses with collagen implants. Collagen grafts persisted as one or two smooth bulges 8 mm in diameter. Collagen incited a brisk foreign body reaction that was surrounded by a fibrous connective tissue capsule. Epiglottises of the horses with collagen implants were significantly thicker 20 mm from the tip than those of normal horses and horses with allografts. Cartilage graft incorporation was not evident grossly and was seen on microscopic examination in only one autograft. Thickening was caused by submucosal fibrosis.  相似文献   
207.
208.
We tested the hypothesis that enhanced feeding success and survivorship of Arctic cod larvae in the Northeast Water polynya (Greenland Sea) are associated with high densities of their zooplankton prey in areas of low sea ice concentration. From late May to early August 1993, first-feeding yolk-sac larvae (6.5–8.5 mm long) were collected primarily along the coast and over shallow banks in the polynya, whereas post yolk-sac larvae (8.5–14 mm) were more uniformly dispersed over the sampling area. Arctic cod larvae < 14 mm fed almost exclusively on copepod nauplii (74% of total prey number) and copepod eggs (16%). Feeding success was defined as the residuals of the regression of the number of prey ingested against larval length. Nauplii density varied from 9600 to 731300 nauplii m-2(equivalent to 0.16 to 12.2 nauplii 1-1) but, contrary to our hypothesis, seldom limited the feeding success of Arctic cod larvae. Water temperature was the best predictor of feeding success in larvae of all sizes. First-feeding success and survivorship were low for larvae hatched before mid-July, and improved thereafter as surface temperatures increased in the open waters of the polynya. There was no relationship between feeding success and irradiance or wind. Assuming a fixed spawning season, it is concluded that a larger fraction of the newly hatched larvae would experience adequate temperatures in years when the polynya opens early. Based on this conclusion, we propose that the timing of the opening of polynyas is a critical determinant of year- class strength in Arctic cod, a key species in the Arctic food web.  相似文献   
209.
An exceptionally large catch of pelagic juvenile lingcod (Ophiodon elongatus) was made just offshore of Point Reyes, California in 1990. Results of 678 midwater trawls from annual surveys from 1983 to 1990 show that pelagic juvenile lingcod have a strong nearshore distribution and were most abundant in the Gulf of the Farallones, with a mean abundance of 5.0 per trawl. Otoliths from fish taken in the large catch were used to estimate parameters of a log-transformed Gompertz growth model, which was then used to calculate hatch dates. Hatching peaked around 24 March and ranged from 10 March to 19 April, implying a January-February spawning season for lingcod off central California. The large catch was associated with an anticyc-lonic eddy which would lead to water being trapped near the coast; convergence of fish associated with the eddy may have been due to either physical or biological effects.  相似文献   
210.
Collagenase, a proteolytic enzyme, was injected intradiscally in nine clinically normal, middle-aged beagles. Calcium chloride diluent solution (control), 100 ABC units of collagenase, and 250 ABC units of collagenase, were injected in randomly selected intervertebral discs (T13-L1 to L5-L6). On day 11, the discs injected with collagenase were narrowed radiographically, but there was no significant change in myelograms. Grossly and histologically, there was dissolution of the intervertebral discs, mainly nucleus pulposus, and protrusion of nucleus material in the vertebral body through bony end-plates in discs injected with collagenase. Collagenase chemonucleolysis may be an alternative to spinal surgery for intervertebral disc protrusion in dogs.  相似文献   
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