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991.
Twenty-eight surgical procedures were performed in 23 dogs with atlantoaxial subluxation. Dorsal stabilization in seven dogs resulted in two recoveries and five failures of fixation. Ventral decompression and stabilization in 18 dogs resulted in eight recoveries and four failures of fixation. Six dogs died or were euthanatized within 7 days of ventral stabilization. Using either technique, four of seven nonambulatory dogs recovered.  相似文献   
992.
A myofascial island flap for abdominal wall reconstruction was based on the lumbar component of the external abdominal oblique muscle and supplied by a major neurovascular pedicle consisting of branches of the cranial abdominal artery, cranial hypogastric nerve, and a satellite vein. The flap was elevated and sutured into a 10 cm x 10 cm body wall defect in five dogs. The dogs were observed for 26 to 28 days. Abdominal wall contour and function were preserved. All dogs developed seromas, two of which became infected. One dog developed a hernia at the dorsal margin of the flap, which was repaired. At necropsy, there was no evidence of dehiscence in any of the dogs. Loose adhesions of omentum to the inner surface of the flap occurred in four dogs. Results of histologic examination confirmed the clinical impression of flap viability. The myofascial island flap has a wide range of mobility over the ventral and caudal areas of the abdomen and lateral thoracic wall. It has potential clinical use for reconstruction of defects within its arc of rotation.  相似文献   
993.
Dehydration, to varying degrees, will inevitably occur in horses participating in endurance trail rides. This water loss is directly related to the amount of body water lost through evaporative cooling, that in turn being related to the amount and rate of work performed, and to the environmental temperature and humidity.An electronic apparatus that can substitute for the conventional and time-consuming venous haematocrit was developed to measure the animals' hydration status. The mechanism of this electrometer is based upon the relationship between the red cell content and the electrical conductivity of the blood. The electrometer reading gave a significant correlation (p<0.001) with the venous haematocrit, thus indicating that the electrometer is a reliable apparatus for determining the animals' hydration status within seconds of venepuncture.  相似文献   
994.
CERES-Maize (Vl. 0) predicted no grain yield when 100% defoliation occurred during vegetative growth. This result conflicted with field observations where 100% defoliation early in the vegetative stage did not materially reduce grain yield. CERES-Maize was modified to realistically predict yields when defoliation greater than 50% occurred during vegetative growth by taking into account stem (stem proper and sheath) photosynthesis and translocation of dry matter from the stem to the developing leaves. With these modifications, predictions from CERES-Maize were in good agreement with field measurements when defoliation occurred both early and later in the vegetative stage. This modified version of CERES-Maize can be the basis of a decision support system for defoliating pests of corn where yields can be evaluated under different management strategies and climate scenarios.  相似文献   
995.
Ticlopidine hydrochloride was evaluated for its effectiveness in inhibiting platelet aggregation and serotonin release in 5 laboratory Beagles before and after heartworm implantation with 7 adult Dirofilaria immitis, and after embolization with 7 dead heartworms to mimic what happens after heartworm adulticide treatment. Five other laboratory Beagles, similarly implanted and embolized with heartworms, were used as nonmedicated controls. During the heartworm-negative stage, the dosage of ticlopidine that inhibited adenosine diphosphate (ADP)-induced platelet aggregation in 5 dogs by at least 50% after 5 days of treatment was 62 mg/kg of body weight once a day. In the same dogs implanted with 7 adult heartworms 21 days previously, mean (+/- SD) ticlopidine dosage required to obtain similar results was 71 (+/- 13) mg/kg given once daily. During the 21 days after dead heartworms were implanted in heartworm-infected dogs, mean ticlopidine dosage was 108 (+/- 35) mg/kg (range, 62 to 150 mg/kg). Ticlopidine treatment was associated with increased platelet numbers in all 5 dogs during the heartworm-negative stage and in 4 of 5 dogs during the heartworm implantation and heartworm embolization stages. Mean platelet volume tended to decrease as platelet numbers increased. At necropsy, gross and histologic pulmonary lesions were less severe in ticlopidine-treated dogs than in nonmedicated control dogs.  相似文献   
996.
Crown reduction is a sterile endodontic procedure indicated for reducing the crown height of teeth. The procedure is used primarily on canine teeth as a disarming technique in aggressive biting pets or to treat traumatic occlusion. Recommendations for using this technique for biting pets are described.  相似文献   
997.
Clinical and endocrinological responses to administration of gonadotropin releasing hormone analog (LH-RH-A) during the lactation period and postweaning in the sow were investigated. Plasma LH concentrations in lactating sows rose immediately after administration of LH-RH-A. However, in postweaning sows the increase of LH level was more slowly. Three of 5 postweaning sows came into estrus and ovulated after LH-RH-A treatment. One sow exhibited a distinct LH response, but her ovaries remained quiescent. The remaining one with feeble estrus for a short period became cystic ovaries. Thus, LH response to GnRH in the sow seems to be higher during early lactation than at 2 days postweaning.  相似文献   
998.
Twenty-five horses admitted for minor orthopaedic or soft tissue surgery were anaesthetised with detomidine, ketamine and halothane. Heart rate, arterial blood pressure, respiratory rate, tidal volume, minute volume, blood gases and occlusion pressures were measured before and for 30 mins after intravenous (iv) injection of saline, butorphanol 0.05 mg/kg bodyweight (bwt) or morphine 0.02 or 0.05 mg/kg bwt. Drug or saline treatment induced no significant changes from pre-treatment values within a group for arterial blood pressure, heart rate, respiratory rate, arterial carbon dioxide tension, arterial oxygen tension and occlusion pressure. In conclusion, both morphine and butorphanol at the stated doses cause no adverse effects on the cardiovascular and respiratory systems of anaesthetised horses.  相似文献   
999.
The behavioural and sedative effects of intravenous (iv) romifidine (40 and 80 μg/kg bodyweight [bwt]) alone or in combination with iv butorphanol (50 μg/kg bwt) were investigated in four ponies and one Thoroughbred horse. Apparent sedation, as judged by the lowering of the head, and by the response to imposed touch, visual and sound stimuli was assessed. The combination with butorphanol reduced the animals' response to imposed stimuli when compared with the effect of the same dose of romifidine alone. Following the administration of romifidine/butorphanol combinations muzzle tremor was noted and some animals attempted to walk forward. In a separate series, the cardiopulmonary effects of iv romifidine (80 μg/kg bwt) alone, or in combination with butorphanol (50 μg/kg bwt) were investigated. Romifidine and the romifidine/butorphanol combination caused similar cardiovascular changes, these being bradycardia with heart block, and hypertension followed by hypotension. Romifidine caused a transient decrease in arterial oxygen tensions and arterial carbon dioxide tensions had increased significantly by the end of the 90 min recording period. Romifidine/butorphanol combinations produced significantly higher arterial carbon dioxide tensions during the first 15 mins after drug administration than did romifidine alone. Butorphanol at 50 μg/kg bwt iv reduced the response to imposed stimuli in horses sedated with romifidine. The combination produced no cardiovascular changes beyond those induced by romifidine alone, but did increase the degree of respiratory depression.  相似文献   
1000.
Over a two month period, 148 dogs presented for surgery had general anaesthesia induced and sometimes maintained with propofol. Excitatory phenomena were recorded on 12 occasions. Signs included muscle twitching, opisthotonus and limb hyperextension (nine cases), and panting with associated activity of the brachiocephalicus muscle and tongue retraction (three cases). The records for a similar two month period were examined for data and observations relating to thiopentone. During this period anaesthesia was induced with thiopentone in 71 dogs and no excitatory phenomena were recorded.  相似文献   
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