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231.
The construction of a simple, portable restrainer for holding sheep in either the horizontal or vertical position for abdominal radiography is described. Examples of its use in locating slow-release pellets-and needles are given. 相似文献
232.
Pulmonic stenosis is caused by a malformed pulmonic valve, stricture of the right ventricular outflow tract or stricture of the pulmonary artery. English Bulldogs, Beagles, Samoyeds, Fox Terriers and Chihuahuas are predisposed. Clinical signs in severely affected dogs include exercise intolerance, stunting, dyspnea, syncope and ascites. Auscultation reveals a high-frequency, crescendo-decrescendo murmur during systole, loudest over the left side of the thorax, near the sternal cardiac border. An ECG may reveal a right-axis deviation of greater than 120 degrees, S waves in leads I, II and III, deep S waves in CV6LL, CV6LU and V10, Q waves deeper than 0.5 mv in leads II, III and AVF, and positive T waves in lead V10. Plain film LAT thoracic radiographs reveal an elevated carina, increased sternal contact of the heart, loss of the cranial cardiac waist and a widened cardiac silhouette, with normal pulmonary vasculature. A DV projection reveals an inverted "D" shape of the right ventricle and a pulmonary artery bulge. A nonselective angiocardiogram reveals poststenotic dilation of the main pulmonary artery. Treatment involves surgical correction of the stenosis. 相似文献
233.
W R Hause 《Modern veterinary practice》1984,65(6):461-465
Pleural effusions can cause dyspnea and cyanosis, and are caused by cardiomyopathy, pyothorax, FIP, FeLV-related disease and trauma. Thoracentesis is used to obtain fluid samples for cytologic examination and culture. Radiographs made after thoracentesis may reveal the cause. Lymphosarcoma causes a sterile exudate containing neoplastic cells. Congestive cardiomyopathy causes a transudate or modified transudate. The sterile exudate of FIP has a proteinaceous background on cytologic examination. The exudate of pyothorax is septic. Treatment depends on the cause but generally includes thoracentesis and supportive care. Cardiomyopathy causes dyspnea, cyanosis, murmurs, gallop rhythms and other arrhythmias. Radiography reveals a globoid heart in the congestive form and a "valentine-shaped" heart in the hypertrophic form. Treatment of congestive cardiomyopathy involves use of furosemide, but is usually unrewarding. Hypertrophic cardiomyopathy is treated with propranolol. Fever may be caused by infection, immune-mediated disease, neoplasia and unknown causes. Treatment is aimed at removal of the underlying cause. 相似文献
234.
Roof WC 《Science (New York, N.Y.)》1984,223(4637):691
235.
The segregation of sulfur in liquid cast iron was studied under conditions of microgravity on Spacelab 1. A rod of cast iron containing carbon, silicon, sulfur, and phosphorus was unidirectionally solidified at four different rates. The influence of sulfur on the graphite structure and the stability of an aluminum oxide skin deposited on the surface of the specimen were investigated. 相似文献
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The earliest fossil record of African anthropoid primates (monkeys and apes) comes from the Jebel Qatrani Formation in the Fayum depression of Egypt. Reevaluation of both geologic and faunal evidence indicates that this formation was deposited in the early part of the Oligocene Epoch, more than 31 million years ago, earlier than previous estimates. The great antiquity of the fossil higher primates from Egypt accords well with their primitive morphology compared with later Old World higher primates. Thus, the anthropoid primates and hystricomorph rodents from Fayum are also considerably older than the earliest higher primates and rodents from South America. 相似文献