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51.
A dorsal surgical approach to the perineal area and rectum was made on 10 healthy, adult dogs. The rectococcygeal muscle was incised and the levator ani and external sphincter muscles were separated to the level of the caudal rectal nerve. All dogs were clinically normal throughout a 3 week postoperative observation period.  相似文献   
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The individual embarking on an iridium-192 brachytherapy program is faced with an abundance of concepts, terms and dosimetry techniques. This article introduces the beginning brachytherapist to the basic physical parameters of iridium-192, to the potential units for source strength and to the general concepts of the various dosimetry techniques. Multiple literature references are listed for more in-depth study.  相似文献   
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Historical, physical examination, clinicopathologic, radiographic and ultrasonographic findings of 13 dogs with hepatic abscesses were reviewed. Liver abscessation was characterized by number, size, shape, echogenicity and location. Solitary lesions greater than 3 cm were more common than multiple ones. The abscesses were mainly poorly echogenic lesions, often with central cavitation. The shape of the lesion ranged from round to oval or irregular. Enhancement artifact, abdominal effusion, regional lymphadenopathy and hyperechoic perihepatic fat, were identified in several dogs. Ultrasound-guided aspiration was performed in 10 of 13 dogs, and confirmed abscessation with cytologic and microbiologic evaluation. Ultrasound-guided percutaneous drainage of abscesses was performed as an adjunct to medical management in four dogs.  相似文献   
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A three month old Appaloosa foal was treated for a refractory pneumonia and Dictyocaulus arnfeldi was found as a causative agent. Eosinophilia in a complete blood count alerted the clinician to the possibility of parasitic involvement and the use of a modified Baermann technique produced larvae of Dictyocaulus arnfeldi. Larvacidal doses of thiabendazole resulted in a dramatic clinical improvement and the foal recovered uneventfully with traditional therapy.  相似文献   
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99mTc-Pertechnetate, 99mTc-mebrofenin, 99mTc-disofenin, 99mTc-sulfur colloid, and 99mTc-Dowex resin beads were evaluated for in vitro stability as a label for both dry extruded, and canned dog food for gastric emptying scintigraphy. A sample of each radiolabeled diet was added to water, gastric juice, intestinal juice, or gastric juice followed by intestinal juice for in vitro digestion. After a 3-hour digestion period, tubes were centrifuged and percentage solid phase retention (%SPR) was calculated. The experiment was repeated three times over a 14-day period to minimize day-to-day variation. For dry dog food, 99mTc-mebrofenin and 99mTc-disofenin had similar %SPR in water (96 and 93%, respectively) and gastric juice (>95% each) and were significantly higher than other labels. For canned dog food, mebrofenin had a 91% SPR for the water or gastric juice digestions, and 99mTc-Dowex had a %SPR of >99%. 99mTc-mebrofenin and 99mTc-Dowex were also tested in vivo, where 99mTc-Dowex had poor stability, and 99mTc-Mebrofenin had excellent stability. 99mTc-Mebrofenin is a suitable label for dog food for gastric emptying scintigraphy.  相似文献   
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This study tested the hypothesis that two-way insertion of an external skeletal fixator trans-fixation pin would weaken the pin-bone interface. Smooth and partially threaded (end) trans-fixation pins were placed in tibiae of 32 cadavers by slow speed drilling or hand placement through a predrilled pilot hole. In one bone of each tibial pair, pins were inserted 2 cm beyond the distal cortex and retracted to a predetermined position (two-way). In the contralateral limb, the pins were inserted in one forward motion to the predetermined position (one-way). The peak force (Newtons) required to extract the pins (pull-out strength) axially at a rate of 1 mm/sec was determined by using a universal testing machine. A significant (p < .05) decrease in pull-out strength was found in pins placed by two-way insertion (674 +/- 410) as opposed to one-way insertion (766 +/- 432). The results of this in vitro study suggest that one-way insertion should be used clinically to decrease weakening of the pin-bone interface and prevent possible failure of external fixators. A significantly greater pull-out strength was found for threaded pins placed in the proximal diaphysis (1459 +/- 330 Newtons) compared to the distal metaphysis (873 +/- 297 Newtons).  相似文献   
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