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81.
A case of congenital biliary atresia in a six-month-old cat is presented. The cat had recurrent bouts of depression, anorexia, vomiting and pyrexia, since it was acquired as a three-month-old kitten. Physical examination showed the cat to be jaundiced. Abdominal palpation revealed several smooth, round masses, confluent with the liver in the right cranial quadrant. A tentative diagnosis of congenital biliary atresia was made based on history, clinical and laboratory examination and radiography. This was confirmed at necropsy.  相似文献   
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83.
Luteal Deficiency and Embryo Mortality in the Mare   总被引:2,自引:0,他引:2  
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84.
New detrital-zircon geochronologic data reveal that a through-going paleoriver connected Texas with Nevada in Late Triassic time. Sandstone from the Upper Triassic Santa Rosa Sandstone (Dockum Group) from northwestern Texas contains a detrital zircon suite nearly identical to that found in western Nevada in the Upper Triassic Osobb Formation (Auld Lang Syne Group, correlative with the Chinle Formation). The Santa Rosa Sandstone was derived in large part from the eroded Cambrian core of the Amarillo-Wichita uplift, as evidenced by abundant zircons with ages of 515 to 525 million years. Other zircon grains in the sandstone are Permian, Devonian, Proterozoic, and Archean in age and, with the exception of the Archean grain, are also matched by the population in the Nevada strata.  相似文献   
85.
Objective— To measure and compare the strain of wires tensioned with alternate (ALT) and simultaneous (SIM) tensioning in a single-ring fixator construct and compare the stiffness of these constructs under axial loading.
Study Design— Experimental mechanical study.
Sample Population— Twenty-four, 84 mm diameter, single-ring constructs.
Methods— Twenty-four, 84 mm diameter, single-ring constructs were assembled using 2 1.6 mm wires placed at a 60° angle tensioned with either ALT or SIM technique to 90 kg tension. Voltage data from a strain gauge were recorded during the wire-tensioning process, cyclic axial loading, and load-to-failure testing. Wire strains were calculated for each wire and compared within constructs and between ALT and SIM groups. Construct stiffness was compared between groups.
Results— There was no difference between the tensioning methods in final wire strains after initial tensioning for both the wire below the ring (W1; P =.698) and the wire above the ring (W2; P =.233). There was also no difference in final wire strains within each tensioning method group (ALT, P =.289; SIM, P =.583). Loss of wire strain (3.5–5%) occurred after cyclic loading for both wires in both groups. There was no difference in construct stiffness between the ALT and SIM groups ( P =.126). Mode of failure was by wire breakage in all constructs and occurred most frequently in W1.
Conclusion— ALT tensioning of wires produced similar wire strains within a single-ring construct after initial tensioning to SIM tensioned wires. There was no difference in construct stiffness under axial loading between AIM and SIM tensioned constructs.
Clinical Relevance— ALT tensioning of wires in a single-ring fixator construct can be used as an alternative to SIM tensioning, as similar initial wire tensions are achieved.  相似文献   
86.
87.
Abstract. The structure of Thelohania duorara Iversen & Manning, 1959, a micro-sporidian parasite of pink shrimp. Penaeus duorarum Burkenroad, was examined with electron microscopy. Earliest developmental stages observed were limited to diplokaryotic cells. Both microtubules associated with exospore formation, and hair-like filaments, projecting from the outer surface of the exospore, were observed during sporogony. The continuity of the cisternae of the polaroplast, the perinuclear cisterna, the outer membrane of the polar filament and membranes surrounding masses of secretion granules were noted. Mature spores had a granular endospore and hair-like filamentous projections on the exospore surface. The polar filament made 13–14 turns, the most distal being slightly constricted. Information presented here indicates that T. duorarum should be retained within the genus Thelohania as it is now defined.  相似文献   
88.
Normal metabolic activity in ovarian follicles may result in oxidative stress and damage to oocytes. The aim of this study was to evaluate expression of the natural anti‐oxidants paraoxonase (PON) 1, 2 and 3 in granulosa cells and PON1 activity in follicular fluid (FF) and plasma of dairy cows. For the first experiment, ovaries were collected from cows at slaughter, after which follicles were dissected and classified as oestrogen active (EAF) or atretic (ATF). Expression of PON1, PON2 and PON3 mRNA was evaluated in granulosa cells, and activity of PON1 was measured in FF. PON1 mRNA was undetectable in granulosa cells, PON2 mRNA expression was not different between follicle types, and PON3 mRNA tended to be higher in EAF (p = 0.11). The activity of PON1 in FF was higher (p = 0.01) for EAF (82.6 ± 8.0 kU/L) than ATF (53.9 ± 6.8 kU/L), as were high‐density lipoproteins (HDL), low‐density lipoproteins (LDL) and total cholesterol concentrations. In the second experiment, we aimed to compare plasma and FF PON1 activity in early lactation Holstein cows (n = 15) with pre‐ovulatory EAF. Activity of PON1 was twofold higher (p < 0.0001) in plasma (122.5 ± 11.1 kU/L) than in FF (61.4 ± 5.2 kU/L). Plasma concentrations were also higher (p < 0.0001) for HDL, LDL and total cholesterol when compared to FF. In conclusion, FF concentrations of PON1, HDL, LDL and total cholesterol were higher in healthy oestrogen active bovine follicles than in atretic follicles. PON1 was not expressed by granulosa cells indicating that high PON1 activity in bovine FF is apparently derived by transfer from blood in association with HDL.  相似文献   
89.
Clinical and pathological findings are described in two recent cases of tuberculosis in the cat; the importance of differentiating this disease from lymphosarcoma is emphasized.  相似文献   
90.
An invasive thymoma associated with pneumothorax and haemothorax is described in a 3^-year-old Labrador Retriever. Diagnosis was based upon radiological and surgical findings and confirmed at autopsy. The case is compared with other thymomas reported in the dog.  相似文献   
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