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31.
A technique for temporary hepatic vascular occlusion during partial hepatectomy for hepatic arteriovenous (AV) fistulas in the dog is presented in seven dogs, and three additional cases of hepatic AV fistulas are reviewed. Hematologic, serum biochemical, radiologic, and nuclear scintigraphic parameters before and after surgery are discussed; abnormalities included anemia, hypoproteinemia, leukocytosis, increased liver function tests, retrograde filling of the portal vein during celiac angiography, and increased arteriovenous ratios during nuclear scintigraphy. Hemodynamic and pathologic findings are presented, and portal hypertension and secondary multiple portosystemic shunts are described. Clinical improvement was observed in four dogs with follow-up periods ranging from 5 months to 3 years.  相似文献   
32.
Aim To determine the normal microbial flora of the koala ejaculate and prepuce in order to select appropriate antibiotics for addition into diluents designed for the preservation of semen.
Procedure Bacteriological samples of the koala prepuce (n = 12) and ejaculate (n = 20) were submitted for microbial culture and sensitivity testing. Microbial flora of ejaculates collected by electroejaculation and artificial vagina were compared. The effects of varying concentrations of penicillin G and gentamicin on sperm motility and on the growth of bacteria in diluted semen stored at room temperature and 16°C over a 24 h period were investigated.
Results A range of bacteria was isolated from the koala prepuce and ejaculate. The predominant organisms in semen collected by electroejaculation and artificial vagina were Corynebacterium spp, none of which could be assigned to any recognised species. The addition of penicillin G and gentamicin to a PBS-based diluent at dose rates of 1000 to 2000 IU/mL and 100 to 200 m g/mL respectively, resulted in no adverse effect on sperm motility over a 24 h incubation period. Penicillin G (1000 IU/mL) and gentamicin (100 m g/mL) prevented growth of bacterial contaminants in diluted koala semen.
Conclusion By controlling the growth of bacteria in extended koala semen, penicillin G and gentamicin are likely to lengthen the period by which spermatozoa can be stored at 16°C and reduce the possibility of disease transmission during artificial insemination procedures.  相似文献   
33.
Reasons for performing study: There are potential advantages to imaging the upper portion of the respiratory tract (URT) of horses during ridden exercise. With the advent of a wireless endoscope, this is now possible. However, there has been no detailed validation of the technique and findings have not been compared to ridden speed. Objectives: To assess the combined use of a Dynamic Respiratory Scope (DRS) and global positioning system (GPS) receiver for examining the URT of a group of Thoroughbred racehorses randomly selected from a single flat racehorse training establishment. Methods: Horses were selected randomly from a population of Thoroughbred horses in training at the same training yard. Endoscopic images of the URT were recorded during a ridden exercise test on an ‘all‐weather‐gallop’ and were reviewed post testing. Speed was measured using a wrist mounted GPS receiver. Results: A total of 67 (34%) of the 195 horses in training were examined. Endoscopic findings included: normal URT function (44 cases); dorsal displacement of the soft palate (DDSP) (13 cases); laryngeal asymmetry (4 cases); and axial deviation of the aryepiglottic folds (3 cases). Maximum speed obtained by individual horses ranged from 41.8–56.3 km/h. Ridden speed was variably affected by DDSP. Conclusions: The DRS provides a safe effective system for imaging the equine URT during ridden exercise at speed. The abnormalities of the URT identified were similar to those observed during treadmill endoscopy studies reported in the literature. The effect of URT abnormalities on ridden speed requires further investigation. Potential relevance: This technique can be used to diagnose common causes of URT associated with poor performance in horses during normal training. This has substantial implications for future clinical diagnosis and treatment of URT pathology.  相似文献   
34.
Radiation therapy requires accurate dose delivery to targets often identifiable only on computed tomography (CT) images. Translation between the isocenter localized on CT and laser setup for radiation treatment, and interfractional head repositioning are frequent sources of positioning error. The objective was to design a simple, accurate apparatus to eliminate these sources of error. System accuracy was confirmed with phantom and in vivo measurements. A head repositioner that fixates the maxilla via dental mold with fiducial marker Z-plates attached was fabricated to facilitate the connection between the isocenter on CT and laser treatment setup. A phantom study targeting steel balls randomly located within the head repositioner was performed. The center of each ball was marked on a transverse CT slice on which six points of the Z-plate were also visible. Based on the relative position of the six Z-plate points and the ball center, the laser setup position on each Z-plate and a top plate was calculated. Based on these setup marks, orthogonal port films, directed toward each target, were evaluated for accuracy without regard to visual setup. A similar procedure was followed to confirm accuracy of in vivo treatment setups in four dogs using implanted gold seeds. Sequential port films of three dogs were made to confirm interfractional accuracy. Phantom and in vivo measurements confirmed accuracy of 2 mm between isocenter on CT and the center of the treatment dose distribution. Port films confirmed similar accuracy for interfractional treatments. The system reliably connects CT target localization to accurate initial and interfractional radiation treatment setup.  相似文献   
35.
Access to markets and raw materials is nearly always mentioned in industrial location studies as an important locational factor. This article demonstrates a methodological approach based on inter-industry linkages and using secondary data to identify target industries for economic development initiatives. In this application we characterize Alabama's industrial base, identify industries with strong forward and backward linkages to base Alabama industries, and highlight a subset of especially good prospects.  相似文献   
36.
The chromosome numbers of nine chimpanzees (Pani troglodytes) have been determined by the bone marrow technique. The diploid number in this species is 48, with a probable XX-XY sex chromosome constitution.  相似文献   
37.
Soil organic carbon(SOC) is the largest terrestrial carbon(C) stock, and the capacity of soils to preserve organic C(OC) varies with many factors,including land use, soil type, and soil depth. We investigated the effect of land use change on soil particulate organic matter(POM) and mineral-associated organic matter(MOM). Surface(0–10 cm) and subsurface(60–70 cm) samples were collected from paired sites(native and cropped) of four contrasting soils.Bulk soils were separated into POM and MOM fract...  相似文献   
38.
Abstract We examined the relationships between fresh and preserved measurements of length and dry weight for larval walleye, Stizostedion vitreum (Mitchill), subjected to freezing and preservation in formalin. Length reductions for both preservation techniques were <5% and decreased with larval size. Dry weight losses ranged from 32·1 to 54·0% for frozen larvae and from 18·2 to 30·1% for larvae preserved in formalin with larger larvae losing proportionately less weight. Freezing caused significantly greater length shrinkage and dry weight loss than preservation in formalin.  相似文献   
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40.
Variation amongst isozymes of Rhynchosporium secalis   总被引:2,自引:2,他引:0  
Mycelial extracts of 288 single-spore isolates of Rhynchosporium secalis. derived from infected leaves collected from seven barley cultivars at nine sampling sites, were subjected to horizontal slab polyacrylamide gel electrophoresis. A total of 28 patterns for α-esterase, four for β-glucosidase and one for β-galactosidase were obtained. One probable isozyme polymorphism, for α-esterase, was identified. There was no correlation between any particular band or pattern and either host cultivar or site.  相似文献   
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