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We report the cases of 2 newborns who underwent at 7 days of age an arterial switch operation for transposition of the great arteries with a rare coronary anomaly: the left and right coronary arteries originated with a single ostium from sinus 1 and the sinus node artery had an isolated origin from sinus 2. The sinus node artery was reimplanted into the new aorta in both patients. Both babies were discharged in sinus rhythm. Preserving the vascularization of the sinus node may avoid the occurrence of postoperative atrial rhythm disturbances. 相似文献
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175.
Histologically confirmed testicular tumors were diagnosed in 410 dogs from 12 North American veterinary university hospitals and clinics. Three tumor-cell types, Sertoli cell tumor, interstitial cell tumor and seminoma, were about equally represented. Several breeds were identified with high risk for different testicular tumor-cell types. Cytogenetic and immunogenetic studies of these dog families could offer leads applicable to familial testicular cancer in man. The multiplicity of breeds within the series suggests that, as in man, other factors, in addition to hereditary, play a role in etiology. Cryptorchid dogs appear to have a 13.6 times higher risk of testicular tumor than normal dogs. Additionally, male dogs with an inguinal hernia have an increased risk (4.7) of testis tumors. There were no detectable excesses of other urogenital anomalies or urogenital tumors among the series. The Shetland Sheepdog is suggested as an appropriate model for research into the mechanisms responsible for testicular maldescent and tumorigenesis. 相似文献
176.
TW Langfitt WD Obrist TA Gennarelli MJ O'Connor CA Weeme 《Canadian Metallurgical Quarterly》1977,186(4):411-414
In order to determine the relationship of cerebral blood flow (CBF) to the clinical outcome of head injury, serial determinations of CBF were performed by the intravenous Xenon technique in 24 patients. The patients were of mixed injury severity and were classified into four groups depending on the neurological exam at the time of each CBF study. All eight patients who were lethargic on admission demonstrated increases in their minimally depressed CBF as they improved to normal status. Eleven patients in deep stupor or coma ultimately recovered. Ten of these patients initially had moderate to profound decreases in CBF which improved as recovery occurred. The single exception was an adolescent whose initial CBF was high but became normal at recovery. Five comatose patients died. In four of these, already depressed CBF fell even lower, while one adolescent with initially increased CBF developed very low CBF preterminally. The data presented in this report demonstrated a good correlation between CBF and clinical outcome. In every one of the adult survivors, depressed CBF increased as the patient recovered to normal status. All adults who died showed a deterioration of CBF as the neurological status worsened. The only exceptions were two adolescents who initially showed high CBF values. In the adolescent who died, CBF dropped to low levels while in the survivor a normal CBF was achieved. Thus in adults a traumatic brain injury was associated with depressed CBF which increased with recovery or decreased further with deterioration while the reaction to injury was quite different in the younger brain. 相似文献
177.
There is experimental and clinical evidence that i.v. injection of bovine testicular hyaluronidase (BTH) reduces the extent of necrosis during myocardial infarction. The fate of i.v. administered BTH has not been described. In this study, serum kinetics of BTH enzyme activity in dogs, rats and humans were determined. Tissue distribution of BTH was determined with an 125I-labeled preparation of purified BTH. Serum BTH activity initially decreased exponentially with half-life 2.0 +/- 0.1 min in dogs with coronary artery occlusion (n = 8; 500 U of BTH/kg); 3.2 min in humans with acute myocardial infarction (n = 2; 500 U of BTH/kg); and 3.2 +/- 0.3 min in rats (n = 5; 5,000 U of BTH/kg). In dogs BTH disappearance showed two distinct phases. After injection of high dose BTH (5,000 U of BTH/kg), during the first 7 min serum half-life of BTH was 2.1 +/- 0.2 min (n = 8), but increased to 9.4 min in later serum samples. After the injection of 125I-labeled BTH into the rat, protein-bound 125I disappeared from serum with a half-life (3.4 min) that is similar to the serum half-life of BTH enzyme activity (3.2 min). Twenty minutes after injection of 125I-labeled BTH, 30% of the label was recovered in the liver. It is concluded that BTH activity has a short serum half-life of less than 10 min in dogs, rats and humans. In the rat model, the disappearance of serum BTH activity results from physical removal of circulating BTH molecules rather than serum inhibition or inactivation of BTH enzymatic activity. 相似文献
178.
JN BeMiller MC Birchenall Sparks TW Fong AJ Pappelis 《Canadian Metallurgical Quarterly》1976,5(6):419-426
In stalk parenchyma tissue of WF9 X 38-11 single corn (Zea mays L.), there was a per cell increase in RNA synthesis and a slight increase in total RNA as cells became older. In cob parenchyma tissue of WF9 X 38-11 single cross corn, both total RNA content and RNA synthesis per cell decreased with the age of cells. In first developed leaf tissue of FR43 X FR14A single cross corn, RNA synthesis increased steadily but only slightly over its life span. The pattern of RNA synthesis and destruction in senescing leaf tissue of seedlings and two sources of parenchyma tissue of maturing plants appeared to differ. 相似文献
179.
In the past six years, 35 patients with thermal injuries have died with a diagnosis of endocarditis. The cause of death in 21 of the 22 patients with acute bacterial endocarditis (ABE) was directly related to complications arising from the ongoing sepsis. In only three cases was the diagnosis considered pre-mortem. The endocarditis was located in the right heart in 18, left heart in 9, and both sides in 8 cases. Associated venous thrombi were present in 14 instances, and 10 of these were septic thrombi. Staphylococcus was the primary organism in the blood in 17 of 22 patients with ABE. Clinically audible murmurs were present in only two patients. In no instance was ABE superimposed upon previously existing valvular disease. ABE can serve as a silent source of sepsis in the burn patient. The diagnosis should be suspected with persistantly positive blood cultures, especially for Staphylococcus aureus, in any burn patient in whom no other foci of sepsis can be identified. Vigorous methods of diagnosis and specific treatment are recommended. 相似文献
180.
JB Hursh MG Cherian TW Clarkson JJ Vostal RV Mallie 《Canadian Metallurgical Quarterly》1976,31(6):302-309
Five human subjects inhaled a mixture of stable and radioactive mercury vapor for periods of 14 to 24 minutes. The subjects retained an average of 74% of that inhaled. Evidence is submitted to show that the retention occurred almost entirely in the alveoli. For 3 days after exposure, the exhaled breath was passed at intervals through activated charcoal traps for sampling periods of 10 to 35 minutes. The data indicated that an average of 7% of the retained mercury was lost in the expired breath, with a half time of 18 hours. Examination of the subjects in a whole body counter yielded average half times for mercury clearance from different parts of the body as follows: lung, 1.7 days; head, 21 days; kidney region, 64 days; chest, 43 days; and whole body, 58 days. 相似文献