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1.
In a previous paper we reported evidence which suggested that a free omental graft has trophic characteristics similar to those of the chorionic epithelium of the early embryo, through which it establishes arteriolar or larger connections with aorta, heart and pericardium within 10 days after it has been placed in contact with the denuded surfaces of each structure. The theory of omental trophism was tested by dropping pieces of omentum completely detached into the pleural and peritoneal cavities of white rats. When examined 25 or more days later a percentage of omental grafts appeared healthy and were attached to pleura, lung, heart and to various structures in the peritoneal cavity. In the pleural grafts, histological sections revealed a continuity between the omental grafts and the sub-pleural tissues. A blood-hungry free omental graft appears to seek out its own blood supply. Neither pleura nor serosa was able to repel its primitive probing for a new blood supply.  相似文献   

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Arthur M. Vineberg  Yutaka Kato 《CMAJ》1965,93(13):709-710
In animal experiments the right internal mammary artery was implanted into the outflow tract of the right ventricle during performance of left mammary artery implantation with epicardiectomy and free omental graft. The effect of double mammary artery implantation operation was tested by triple coronary artery ameroid constriction in 24 animals. In 20 animals studied both implanted arteries remained open and had commenced to bud and branch at the time of examination. The double implant operation is still an experimental procedure.  相似文献   

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本文设计一种由胶原和高分子聚合物组成的新型生物一人工复合血管。其研制过程是将包绕有聚酯网的硅胶棒埋入羊的皮下组织,再将形成的经聚酯网为支架的胶原管经醛化处理。作者通过肉眼和SEM观察提出了研制生物——人工复合血管的要点:聚酯网网孔要合适,其与硅胶棒的间隙要恰当,理化处理方法更要选择好。  相似文献   

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The importance of triple coronary artery disease was evident in 125 patients undergoing internal mammary artery implantation, when some patients died from right coronary artery occlusion. This occurred even when the internal mammary artery was patent and revascularizing the left ventricle.In 1961 the free omental graft operation was developed to revascularize both right and left ventricles. In animals this operation has proved most effective in preventing death after application of Ameroid constrictors to all three coronary arteries. Arteriolar or larger-sized vessels rapidly formed between the aorta and omentum and the pericardium and omentum and the heart and omentum.Two patients with triple coronary artery disease underwent internal mammary artery implantation and free omental graft early in December 1962. Postoperative convalescence was uneventful. They have returned home and appear to be improved. Wrapping the entire heart with the free omental graft has produced little reaction, suggesting that, as in the animal, the grafts are surviving.  相似文献   

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One hundred and forty patients with coronary artery disease treated by internal mammary artery implantation were followed up from six months to 13 years. The mortality rate was 3%; improvement was obtained in 70%. Occlusive disease of all three major coronary arteries, however, requires more blood than can be supplied by the implant procedure, and the free omental graft operation was developed for the management of selected patients with this condition. Normally in animals triple coronary artery ameroid constriction results in 100% mortality. When the free omental graft operation, with or without internal mammary artery implantation, was performed, 80% of such animals survived. The free omental graft forms capillary anastomoses in three days and arteriolar vessels in eight days, which leave the base of the aorta, enter the omentum, thence to the myocardium. A combined internal mammary artery implantation and free omental graft operation was performed in 17 patients with triple coronary artery disease as shown by cine coronary arteriography. There was no operative mortality, and 12 of the patients are free of pain and have returned to work.  相似文献   

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L. J. Harris 《CMAJ》1964,91(3):128-130
After laparotomy, immediate compression of the aorta with the heel of the hand just above the bifurcation of the common iliac arteries is a quick and effective way of controlling catastrophic pelvic hemorrhage. This maneuver, which can be maintained for several hours without any harmful sequelae, enables the surgeon to remove the blood from the peritoneal cavity and take definitive steps to stop the bleeding, and the loss of administered blood is halted. An instrument for aortic compression is described which is easily applied to the aorta; it is controlled by a handle outside the abdomen and does not obstruct the operative field. It has been found to be valuable, not only in the control of serious pelvic hemorrhage, but also in pelvic surgery where considerable blood loss is anticipated.  相似文献   

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This study examines the effects of intravenous infusion of adenosine and sublingual nitroglycerin on coronary angiograms obtained by current-generation multidetector computed tomography. We assessed coronary vasodilation at baseline and after intravenous adenosine (140 µg/kg/min) or sublingual nitroglycerin spray (800 µg) in 7 female swine (weight, 40.9 ± 1.4 kg) by using electrocardiogram-gated coronary angiography with a 64-detector scanner (rotation time, 400 ms; 120kV; 400 mA) and intravenous contrast (300 mg/mL iohexol, 4.5 mL/s, 2 mL/kg). Cross-sectional areas of segments in the left anterior descending, circumflex, and right coronary arteries were evaluated in oblique orthogonal views. Images were acquired at an average heart rate of 73 ± 11 beats per minute. Changes in aortic pressure were not significant with nitroglycerin but decreased (approximately 10%) with adenosine. Of the 76 segments analyzed (baseline range, 2 to 39 mm2), 1 distal segment could not be assessed after adenosine. Segment cross-sectional area increased by 11.3% with nitroglycerin but decreased by 9.6% during adenosine infusion. The results of the present study are consistent with the practice of using sublingual nitroglycerin to enhance visualization of epicardial vessels and suggest that intravenous adenosine may hinder coronary artery visualization. This study is the first repeated-measures electrocardiogram-gated CT evaluation to use the same imaging technology to assess changes in coronary cross-sectional area before and after treatment with a vasodilator. The nitroglycerin-associated changes in our swine model were modest in comparison with previously reported human studies.Abbreviations: LAD, left anterior descending artery; MDCT, multidetector computed tomographyRecent advances in multidetector computed tomography (MDCT) for coronary angiography, their increased availability, and the pending release of a new generation of CT scanners contribute to this methodology''s potential for revolutionizing the early diagnosis and functional assessment of coronary artery disease.15,16,25 However, the benefits of methodologic advances do not diminish the need to validate and assess the safety, efficacy, and costs of technology.15 In this regard, the present study uses an animal model with coronary anatomy analogous to that of humans11,43 to assess the effects of sublingual nitroglycerin and intravenous adenosine on coronary epicardial vessel visualization by using baseline imaging as a control. The radiation exposure associated with CT procedures precludes human studies that involve repeated measures on the same subjects.Sublingual nitroglycerin is hypothesized to enhance the visualization of epicardial coronary vessels due to its vasodilatory properties.8-10 Nitroglycerin acts as a nitric oxide generator to induce relaxation of vascular smooth muscle independent of endothelial function.1,18,20 Current evidence supporting improved coronary visualization with sublingual nitroglycerin is derived from clinical cross-sectional studies that compare results in different groups of patients with heterogeneous coronary lesions.5,6,16,27,44 A recent survey reported that more than 80% of facilities in the United States routinely use nitroglycerin in cardiac MDCT angiography.23In contrast to the action of nitroglycerin on epicardial vascular smooth muscle, intravenous adenosine frequently is used as a pharmacologic stress to affect vasodilatation within the coronary microcirculation.20 Although current-generation CT scanners have limited capability to assess myocardial tissue perfusion, research efforts from advanced imaging centers suggest that future-generation CT scanners soon will permit myocardial perfusion imaging.13,14,29 No studies to date have assessed epicardial vessel changes by MDCT with intravenous doses of adenosine appropriate for myocardial perfusion imaging.The objective of this study was to provide an animal model for MDCT studies that permits repeated measures of epicardial vessels without the limitations of cross-sectional designs or the complications of heterogeneity of vascular lesions within clinical populations. This study used routes of administration of nitroglycerin and adenosine that are consistent with clinical practice.  相似文献   

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Usefulness of intestinal perfusion in the treatment of uremia is limited by (a) low clearances, (b) atrophy of the perfused mucous membrane, and (c) poor toleration by the patient. A method of intestinal perfusion has been devised which uses most of the small bowel without exclusion from the fecal stream. Two Roux-en-Y anastomoses are made, the proximal 12″ below the ligament of Treitz, the distal 18″ above the ileocecal valve. Perfusion is carried out between the proximal jejunostomy and distal ileostomy, daily. Six litres of fluid are perfused in four hours. The bowel is used for digestion during the remaining 20 hours of the day. Patients have solid bowel movements daily, prior to perfusion. Reflux of intestinal contents, between perfusions, is slight. The method allows maximal diffusion, may prevent bowel atrophy and is well tolerated by the patient. The method is being used, in conjunction with hemodialysis, in treatment of chronic uremia.  相似文献   

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孙铎 《昆虫学报》1960,(2):222-222
本溪地区的蚊虫过去未有过文献报告。我们于1957—1958年,在本溪地区(本溪市、本溪县)进行了蚊虫的初步调查。经两年的调查已发现的蚊种,有按蚊属1种,伊蚊属4种,库蚊属6种,共计11种。其名称如下:  相似文献   

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The auditory sensitivity of adult mice has been investigatedusing a method that has not been previously described. Thismethod involves recording the electromyogram (EMC) from thepost-auricular muscles in response to tonal stimuli. The preliminaryresults presented here show a secondary, high-frequency peakof sensitivity in the audiogram, which approximately correspondsto the frequency of sound emitted by that species; this confirmsthe findings of previous workers. The advantages and disadvantagesof using the post-auricular EMG response as a measure of auditorysensitivity are briefly discussed in comparison with other behavioraland physiological methods.  相似文献   

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2012年在日照黄泥梁遗址的调查、试掘工作中共获得石制品75件,其中试掘出土者71件,地表采集者4件。试掘石制品埋藏于黄土地层的古土壤层中,石制品个体较小,原料以闪长玢岩和脉石英为主,类型包括石核、石片、石器、断块等,属石片石器工业组合;地表石制品原料主要为燧石,类型有细石核、细石叶、端刮器等,属细石器工业组合。本次的调查、试掘确认了黄泥梁遗址的原地埋藏属性,肯定了遗址的发掘潜力和研究价值。黄泥梁遗址的发现和研究将推动山东旧石器考古研究的进展。  相似文献   

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