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Prof. Dr. H. Wenk J. Träger H. Daum E. S. Debus H. Imig H. Kortmann 《Gef?sschirurgie》2004,9(3):191-195
In a prospective, randomized multicenter trial, 175 patients with abdominal aortic aneurysms were treated by conventional operation. Two types of polyester prostheses (Gelsoft Plus, Vascute Terumo Corp., Hamburg, Germany or Microvel, Boston Scientific, Ratingen, Germany) were selected randomly for implantation. Diameters ranged from 14 to 20 mm. The diameters of the grafts were measured by ultrasound postoperatively, as well as 6, 12, and 24 months after operation. Local and systemic complications were recorded. Dilation of the main body of the “Gelsoft plus” prosthesis was 19% within the first 12 months and 30% for the Microvel prosthesis. Extreme dilation was not observed. Thus, vascular prostheses must be chosen small enough and the dilation of 20–30% should be considered. The most frequent complication was incisional hernia (32%). 相似文献
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The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented. 相似文献
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In Alzheimer's disease (AD), pathological changes are found in the basal forebrain cholinergic system (BFCS), serotonergic raphe (RA), and noradrenergic locus coeruleus (LC) systems. The present study was designed to determine the extent to which selective damage in each of these systems individually could produce an impairment of memory, one of the clinical symptoms of AD. Rats were given selective lesions by injecting ibotenic acid into the nucleus basalis magnocellularis and medial septal area (i.e., BFCS); 5,7-dihydroxytryptamine into the medial and dorsal RA; and 6-hydroxydopamine (6-OHDA) into the LC or by ip injections of (2-chloroethyl)N-ethyl-2-bromobenzylamine HCl (DSP4). Levels of choline acetyltransferase (ChAT), norepinephrine, and serotonin verified lesion effectiveness and selectivity. Chronic changes in serotonergic-2 and beta-adrenergic receptors were also determined. Rats were tested in a delayed spatial alternation in a T-maze. BFCS lesions impaired choice accuracy with intertrial delays of 5, 30, and 60 s. RA lesions or DSP4 injections impaired choice accuracy only when the intertrial delay was 60 s. LC lesions (by 6-OHDA) did not impair choice accuracy at any delay. The results suggest that the pathological changes in the BFCS and RA are sufficient to produce the types of memory impairments associated with dementia, but the quantitative effects of pathology in these two systems are different. 相似文献
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The present study investigated the specific ways by which cytotoxicity due to glutamate receptor stimulation could be attenuated by the administration of agonists and antagonists of the ionotropic and metabotropic glutamate receptors within the nucleus basalis magnocellularis (NBM) of rats as measured by cortical choline acetyltransferase activity. The results of these studies suggest that (1) the cytotoxicity of ibotenate to NBM cholinergic cells is not dependent upon stimulation of metabotropic glutamate receptors, but results from activation of
(NMDA) receptors, (2) the cytotoxicity of quisqualate to cholinergic cells within the NBM is not dependent upon stimulation of NMDA or metabotropic receptors, and (3) the cytotoxicity of NMDA was prevented by administration (i.p.) of the un-competitive NMDA antagonist memantine (30 mg/kg), resulting in plasma levels of 2.5 μg/ml, a concentration known to block efficiently NMDA receptors in vitro. Finally, performance of a food-motivated, delayed-alternation task on a T-maze was impaired by injections of NMDA into the NBM, but was prevented by co-administration of NMDA with memantine. 相似文献
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A modified technique for catheterization of the pulmonary artery was developed. It involves the passage of a tapered, movable-core, J-tipped guide wire across the right ventricle into the pulmonary artery followed by the advancement of a straightened Grollman pigtail catheter. The technique was successful in 34 of 34 pulmonary artery catheterizations. The method avoids prolonged catheter manipulation within the right ventricle. In addition, since the catheter does not cross the tricuspid valve until the guide wire has been advanced, the occasional complication of the pigtail "hooking" on a tricuspid valve leaflet or chordae tendineae during catheter withdrawal and manipulation is prevented. 相似文献
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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
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