Magnetic resonance imaging following unilateral occlusion of the renal circulation in rabbits

Magnetic resonance studies at 0.12 T were performed following acute unilateral occlusion of the renal artery or vein in rabbits. Prior to occlusion, in vivo and in vitro relaxation times of the renal cortex and outer medulla were similar. After venous occlusion, T1 and T2 were prolonged on the occluded side, while the contralateral side remained unchanged. After arterial occlusion, the outer medulla of both the occluded and contralateral kidney exhibited prolonged relaxation times. There was a significant linear correlation between T1, T2, and the water content of the tissue. The authors conclude that quantitative in vivo relaxation times may eventually prove to be useful in diagnosis, although at present they are less reliable than those obtained in vitro.     

胃癌雌激素受体的研究

自20世纪60年代发现雌激素受体以来,学者们开展了对各种不同器官肿瘤受体的研究,并形成了激素作用机制的3种模式(二步模式、核模式和平衡模式).目前已在众多的肿瘤中发现了性激素受体,如孕酮激素(PR)、雌激素(ER)和雄激素(AR).这些肿瘤包括激素依赖性器官和非依赖性器官的肿瘤.     

Eighty-year-old men without cardiovascular disease in the community of Malmö.: Part II. Smoking characteristics and ultrasound findings,with special reference to glutathione transferase and pyridoxal-5-phosphate

Abstract. A total of 1280 80-year-old men in the community of Malmö were questioned about smoking habits and the occurrence of cardiovascular disease (CVD). After a careful medical and duplex ultrasound examination, four groups were selected for further studies: (1) no CVD, non-smokers; (2) no CVD, smokers; (3) CVD, smokers; (4) CVD, non-smokers. In total 122 individuals participated. The average tobacco consumption by smokers was 13 g d^?1 for 59 years. In the CVD group 45% of subjects had atherosclerotic symptoms at more than one site. Smoking was found to be correlated with lower extremity atherosclerosis, cholesterol and LDL cholesterol were correlated with carotid artery lesions and pathological ankle/arm index, and blood pressure was correlated with lower extremity lesions. In contrast with middle-aged populations, individuals with an increasing degree of lesions in the lower extremities had a larger percentage of high glutathione transferase activity than subjects without CVD. Smokers had significantly lower pyridoxal-5-phosphate levels than non-smokers. It is concluded that some heavy smokers might reach an advanced age in good health. Smoking was also operative as a risk indicator for lower extremity atherosclerosis in 80-year-old individuals.     

Assay of 1-nitropropane, 2-nitropropane, 1-azoxypropane and 2-azoxypropane for carcinogenicity by gavage in Sprague--Dawley rats

1-Nitropropane (1-NP), 2-nitropropane (2-NP), 1-azoxypropane(1-AP) and 2-azoxypropane (2-AP), were assayed for carcinogenicityby gavage in male Sprague—Dawley rats. 2-NP was givenat 1 mmol/kg three times per week for 16 weeks. 1-NP (1 mmol/kg),1-AP (0.1 mmol/kg), 2-AP (0.1 mmol/kg) or Emulphor EL-620 vehiclewas given three times per week for 16 weeks, and then once perweek for 10 weeks. In the 2-NP treated group both benign andmalignant liver tumors occurred in 100% of the animals. No treatmentrelated tumors occurred in rats receiving 1-NP. In rats treatedwith 1-AP, a high incidence of skin tumors (100%), mostly keratoacanthomas,and of tumors of the nasal cavity (59%) was observed. Rats whichwere given 2-AP also showed an increased incidence of skin keratoacanthomas(21%), but not of other tumors. These findings (i) confirm,using the oral route of administration, the results of inhalationstudies by others indicating the potent hepatocarcinogenicityof 2-NP, (ii) establish a practical model in which the mechanismof 2-NP carcinogenicity can now be more readily studied, and(iii) demonstrate that 1-AP, and probably 2-AP, like other aliphaticazoxy compounds thus far examined, are carcinogenic in rats.     

Excretory urography with iohexol: evaluation in children

A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent.     

Orthotopic cardiac transplantation: evaluation with CT

As cardiac transplantation has become widely available, computed tomography (CT) of the chest has played a useful role in the examination of patients after heart transplantation. To determine anatomic features related to the procedure, the authors evaluated 59 scans in 46 patients who had undergone orthotopic cardiac transplantation. Aortic anastomosis (seen in 98% of scans) and altered spacing between the great vessels (83%) proved to be the most common and most reliable findings. Other features including atrial anastomosis, high main pulmonary artery segment, remnant superior vena cava, and cardiac reorientation were also seen. Accurate interpretation of adenopathy, mediastinal abscess, and pericardial effusion will be enhanced in these patients through a better understanding of the cardiovascular-pericardial complex, which is afforded by CT.     

Progress in laparoscopic anatomy research: A review of the Chinese literature

The development of laparoscopic surgery has generated the new field of study, laparoscopic anatomy. This article reviews the reported literature on laparoscopic anatomy and explores how it has evolved along with advances in abdominal surgery. In addition, the principal concerns in current laparoscopic anatomy research are discussed, including: (1) types of special adjacent anatomical structures; and (2) special surgical planes and anatomical landmarks. Understanding of systematic laparoscopic anatomy can pr...