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991.
Surgical treatment of hepatic and biliary disease requires a thorough knowledge of pertinent anatomy and pathophysiology. Proper attention to both preoperative and postoperative care is important. This article describes many of the more common surgical manipulations of the liver and biliary tract, as well as pre- and postoperative considerations.  相似文献   
992.
On the basis of clinical and laboratory examinations, a ventricular septal defect or a variant of the tetralogy of Fallot was suspected in a 3-year-old filly with a history of poor growth rate and exercise intolerance. The filly was euthanatized and found to have a 3-chambered heart (cor triloculare biatriatum). The heart had 2 normally formed atria and a large common ventricle into which the right and left atrioventricular orifices opened and from which the aorta arose. There was a small separate chamber from which the pulmonary trunk originated. This chamber communicated with the common ventricle through a large oval opening along the dorsal border of the displaced, interventricular septum.  相似文献   
993.
994.
The effect upon the reproduction of total resection of the oviductal isthmus, including the uterotubal and ampullary-isthmus junctions followed by end-to-end ampullo-cornual anastomosis was studied in pigs. Normal cycling gifts of proved fertility were submitted to bilateral isthmus deletion (Group I). Other gilts were submitted only to unilateral isthmic resection, while their contralateral medial isthmus was transversally cut and reanastomosed (Group II). A significantly lower nidation index was obtained after bilateral isthmic resection. The gilts in Group I which did not become pregnant and those in Group II were successfully mated during forthcoming standing oestruses, and were in association to that slaughtered on days 3, 4, or 5 of the cycle, and the characteristics and location of ova were determined. Spermatozoa fertilized the ova, and those cleaved normally in the isthmic-resected tube as well as in the sham-operated oviducts. The isthmic-resected oviduct, however, did not transport cleaved ova into the uterus at the time expected as normal. The findings suggest that the fertilized pig ova cannot reach the uterus at the normal expected time in case of total absence of the isthmic part of the oviduct, resulting in impaired fertility.  相似文献   
995.
996.
997.
998.
Eleven isolates of H2S-producing Escherichia coli were recovered from necropsy materials of chickens with symptoms and lesions of colisepticemia on Saudi Arabian broiler farms. Results of 19 out of 20 biochemical reactions studied were typical for E. coli. Hydrogen sulfide production by the E. coli isolates was used as an epidemiological marker to pinpoint a breeding farm as the probable source of these strains, which were then transferred to progeny farms, where colisepticemia occurred. This finding was confirmed by the presence of the same antigenic structure (O78:H-) and by the same drug-resistance pattern (a multiple resistance to streptomycin, sulfathiazole, and tetracycline) in the isolates.  相似文献   
999.
Occipito-atlanto-axial malformation with atlanto-axial subluxation was diagnosed radiographically in a 4-day-old Holstein calf with a short neck, symmetric ataxia, and tetraparesis, indicative of a cervical spinal cord lesion. Necropsy confirmed the clinical diagnosis and revealed ribs on C-7, with partial fusion of C-7 and T-1. Histologic examination revealed focal degeneration of the spinal cord in the second cervical segment at the level of the atlanto-axial joint and extensive secondary neuronal fiber degeneration possibly caused by spinal cord trauma that occurred in utero.  相似文献   
1000.
The significance of leptospiral titres associated with bovine abortion   总被引:1,自引:0,他引:1  
To investigate relationships between serological titres to 2 serovars, pomona (L. pomona) and hardjo (L. hardjo), of Leptospira interrogans and abortions, log linear and logit models were fitted to herd and individual cow data from cattle serologically negative for brucellosis. Serological titres to both serovars were significantly related to abortions in individual cows, with L. pomona having a stronger relationship than L. hardjo. L. hardjo was not significant when herd data were analysed. Differences between dairy and beef cattle in the serological titres found to both L. pomona and L. hardjo were detected when data sets of all cattle or cattle with no history of abortion were analysed. The beef/dairy differences may be due to different management practices and/or to different geographical distributions of both serovars and populations of beef and dairy cattle. If there are no cattle in a herd with a reciprocal titre of 3000 or greater for L. pomona, it is unlikely that L. pomona is associated with the abortion problem. There was no specific L. hardjo titre which separated high and low probabilities that the serum came from a cow or herd with an abortion history.  相似文献   
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