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61.
We examined the visceral blood flow distribution during infusion of three vasodilators at doses that produced similar depression of systemic arterial pressure. The studies were performed in pentobarbital-anesthetized dogs using the radioactive microspheres technique. Minoxidil did not alter renal, total visceral, or visceral organ flow distribution with the exception of a modest increase in relative stomach blood flow. Nitroprusside increased the percentage of total visceral flow to the spleen and the hepatic artery. Dopamine increased blood flow to the stomach, intestine, and kidney. After phenoxybenzamine, the augmentation of stomach blood flow by dopamine was greatly increased, while blood flow to the splenic, pancreatic, and hepatic arteriolar vascular beds decreased. The decreases in blood flows may be due to decreased perfusion pressure in the absence of active vasodilation or to myogenic or metabolic autoregulation. Thus, at equivalent hypotensive responses, the vasodilator compounds that we studied produced markedly different patterns of visceral blood flow. 相似文献
62.
63.
Cryosurgical ablation of accessory atrioventricular connections: a method for correction of the pre-excitation syndrome 总被引:3,自引:0,他引:3
JJ Gallagher WC Sealy RW Anderson J Kasell R Millar RW Campbell L Harrison EL Pritchett AG Wallace 《Canadian Metallurgical Quarterly》1977,55(3):471-479
Cryothermia, a new technique for definitive treatment of the pre-excitation syndrome, is described in two patients. The first patient presented with a normal P-R interval with a delta wave and reciprocating tachycardia. Preoperative electrophysiologic study suggested a free-wall atrioventricular connection on the left posterior atrioventricular (A-V) groove. At surgery, epicardial mapping confirmed the site of pre-excitation on the posterior left ventricular (LV) wall. An electrogram arising from the accessory pathway (AP) was recorded at the site of earliest ventricular activation. Interatrial delay combined with an apparently long accessory pathway to the ventricle caused the P-R interval to appear normal. Local pressure abolished pre-excitation. The site of early ventricular activation was cooled to -60 degrees C with a specially designed cryoprobe. All evidence of pre-excitation and arrhythmias disappeared. The second patient presented with a refractory reciprocating tachycardia and was found to have an AP in the septum capable of only retrograde conduction. Retrograde conduction was abolished by applying a temperature of 0 degrees C to the anulus at this site during tachycardia. Conduction over the AP and reciprocating tachycardia returned with rewarming. Ablation of the AP was obtained by applying a temperature of -60 degrees C for 90 seconds on two occasions to the same area. The His bundle was not injured. 相似文献
64.
AS Lachman TL Spray DM Kerwin GI Shugoll WC Roberts 《Canadian Metallurgical Quarterly》1977,63(4):615-622
Massive medial calcific deposits (M?nckeberg's calcinosis) are described in the peripheral and visceral arteries, and similar but small-sized deposits in the coronary arteries of a 41 year old woman with diabetes mellitus. Although observed by roentgenogram fairly commonly during life in the muscular arteries of the legs in middle-aged men, medial calcinosis infrequently involves the visceral arteries and has never, to our knowledge, been documented in the coronary arteries. Although it may be associated with intimal atherosclerosis, medial calcinosis, per se, does not obstruct the lumens of the arteries and, therefore, does not lead to symptoms or signs of limb or organ ischemia. The cause of medial calcinosis remains a mystery, but it appears to affect people with diabetes more frequently than those without. 相似文献
65.
During the synthesis of 3-hydroxy-3-ethinylquinuclidine (I), two additional products were isolated and identified as (E)-3-[2-(3-oxoquinuclidine)]quinuclidylidene (III) and (E)-3-[2-(3-hydroxy-3-ethinylquinuclidine)]quinuclidylidene (V). The base-catalyzed autocondensation of 3-quinuclidinone resulted in the alpha,beta-unsaturated ketone dimer (III) as a single isomer. The geometric configuration was deduced by examination of the NMR spectra of the methyl iodide salt. Compound V was thus the result of attack on the carbonyl carbon of III by the acetylide anion. The isolation and identification of these compounds clarified the reported differences in the physical properties of I and its analogs. 相似文献
66.
JF Burke WC Quinby CC Bondoc EM Sheehy HC Moreno 《Canadian Metallurgical Quarterly》1977,186(3):377-387
A new system of patient protection from bacterial crossinfection called the Bacteria Controlled Nursing Unit (BCNU) is described, based on strict environmental control of a 6 x 10 foot area surrounding the patient's bed rather than the entire patient room or isolation ward, plus the ability to deliver all medical care without entering the protective environment and maintaining all monitoring, life support, and i.v. equipment outside the controlled environment. The clinical effectiveness of this system in the treatment of burn patients has been studied and compared with the effectiveness of single room isolation on a burn isolation ward and conventional isolation techniques on an open burn ward. The studies show that the BCNU is significantly more effective in preventing bacterial cross-contamination than conventional precautions (3.8% vs. 13.1%, P < 0.001; and 8% vs. 22.8%, P < 0.001) over a two and four week period. The studies also indicate that there was a significant increase in the probability of infection occurring following cross-contamination than occurring after auto-contamination (65% vs. 39%, P < 0.005), emphasizing the importance of preventing cross-contamination in reducing the overall infection rate in seriously burned patients. Clinical evaluation of the unit proved it to be compatible with intensive nursing and medical care without increasing the nurse to patient ratio. The unit provided sufficient control of bacterial cross-infection to allow reduction in mortality and improvement in the effectiveness of burn care through routine prompt excision of burn eschar and immediate wound closure to be carried out in severe and massively burned patients without a limiting threat of bacterial burn wound sepsis. 相似文献
67.
Fistulas between the abdominal aorta and renal vein are exceedingly rare. Diagnostic delays are not unusual. Correction can be extremely difficult because of anatomical distortion and size of the arterialized veins. A young woman with such a fistula following a gunshot wound is presented. Four years following injury, the fistula was repaired successfully during intentional arrest of the circulation for 7 minutes. This was accomplished with deep hypothermia and cardiopulmonary bypass. No serious problems occurred during the operation. The patient tolerated the procedure well and has been relieved of her symptoms completely. Most patients with traumatic or spontaneous arteriovenous fistulas can be managed safely and effectively by conventional operative techniques. In selected situations, the risk of total circulatory arrest and deep hypothermia may be less than the risk of uncontrollable bleeding inherent in conventional techniques. Suggested indications for use of total circulatory arrest in vascular surgery are (1) inability to achieve vascular control by more conventional means, (2) massive distention of regional veins as occurrs in well established fistulas of the trunk, (3) one or more prior corrective attempts with use of conventional techniques, and (4) anticipated anatomical distortion and/or multiple abnormal vascular communications. This technique is a valuable approach to the correction of otherwise inoperable cardiovascular lesions. 相似文献
68.
Clinical and morphologic observations are described in a 46 year old woman with fatal trichinosis. Attention is called to the occurrence of extensive ventricular endocardial damage with superimposed thrombosis; Evidence is presented to indicate that the most likely cause of the endocardial damage is the associated eosinophilia. The mechanism by which eosinophils damage endocardium, however, remains obscure. 相似文献
69.
A mixture of sulfacetamide, sulfathiazole, and sulfabenzamide was used to develop a rapid high-pressure liquid chromatographic assay. In addition, this study provided a means to develop concepts relating solvent molar polarization parameters and retention times. A linear correlation between molar polarization and retention time was observed and will permit reasonably rapid predictions about the dependent variable. 相似文献
70.