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排序方式: 共有489条查询结果,搜索用时 15 毫秒
1.
Shamil D. Akhmedov M.D. Euvgenily V. Krivoschekov M.D. Mariana V. Pekarskaya M.D. Alexander L. Krylov M.D. Zhanna V. Vesnina M.D. Vladimir I. Chernov M.D. Alexander M. Chernyavskiy M.D. Yuriy Y. Vechersky M.D. Rostislav S. Karpov M.D. Edward A. Nechaev M.D. Vikenty V. Pekarski M.D. 《Journal of cardiac surgery》1995,10(5):573-579
Thirty-five cardiomyoplasty procedures were performed in five patients with dilated and 30 patients with ischemic cardiomyopathies. Russian-made cardiomyostimulators (CMS) were implanted in these patients. Twenty-one patients underwent a one-step procedure using a left thoracotomy for cardiomyoplasty, while in 14 patients, a two-step procedure that included a mid-line sternotomy was carried out. During the average follow-up period of 9 ± 2.1 months, studies were carried out that showed in survivors improved clinical functional status and decreased heart failure symptoms. Evidence of revascularization of the ischemic myocardium from the latissimus dorsi muscle (LDM) wrap was obtained by angiography and radioactive scintigraphy. In five patients, the CMS had to be removed due to complications, and in all these patients, their clinical functional status deteriorated following the cessation of cardiomyostimulation. 相似文献
2.
Physiological systems that must operate over a range of temperatures often incorporate temperature-compensatory mechanisms to maintain their output within a relatively narrow, functional range of values. We analyze here an example in the accessory radula closer (ARC) neuromuscular system, a representative part of the feeding neuromusculature of the sea slug Aplysia. The ARC muscle's two motor neurons, B15 and B16, release, in addition to ACh that contracts the muscle, modulatory peptide cotransmitters that, through a complex network of effects in the muscle, shape the ACh-induced contractions. It is believed that this modulation is critical in optimizing the performance of the muscle for successful, efficient feeding behavior. However, previous work has shown that the release of the modulatory peptides from the motor neurons decreases dramatically with increasing temperature. From 15 to 25 degrees C, for example, release decreases 20-fold. Yet Aplysia live and feed successfully not only at 15 degrees C, but at 25 degrees C and probably at higher temperatures. Here, working with reduced B15/B16-ARC preparations in vitro as well as a mathematical model of the system, we have found a resolution of this apparent paradox. Although modulator release decreases 20-fold when the temperature is raised from 15 to 25 degrees C, the observed modulation of contraction shape does not decrease at all. Two mechanisms are responsible. First, further downstream within the modulatory network, the modulatory effects themselves-experimentally dissected by exogenous modulator application-have temperature dependencies opposite to that of modulator release, increasing with temperature. Second, the saturating curvature of the dose-response relations within the network diminishes the downstream impact of the decrease of modulator release. Thus two quite distinct mechanisms, one depending on the characteristics of the individual components of the network and the other emerging from the network's structure, combine to compensate for temperature changes to maintain the output of this physiological system. 相似文献
3.
Shebzukhov YV Koroleva EP Khlgatian SV Lagarkova MA Meshcheryakov AA Lichinitser MR Karbach J Jager E Kuprash DV Nedospasov SA 《Immunology letters》2005,100(1):88-93
Thymidylate synthase (TYMS), the critical enzyme for DNA synthesis and a target for chemotherapy, was recently characterized as an oncogene and a potential target for specific immunotherapy. Here we report TYMS-specific antibody response in a fraction of colon cancer patients. Humoral immune response to TYMS is induced by chemotherapy using TYMS inhibitors, such as 5-fluorouracil (5-FU), and may be associated with tumor burden. Therefore, TYMS may serve as a useful serological biomarker for monitoring the course of disease and treatment in cancer patients. 相似文献
4.
B S Briskin E A Tartakovski? N A Gvozdev Ia I Iakobishvili S N Magomedov 《Khirurgiia》1999,(10):53-56
Of 3721 patients with diabetic lesions of the foot treated 2416 (65%) patients have been operated. The rise of urgent hospitalization rate (over 90%) unfavourably influenced the results of the treatment and contributed to increased frequency of high amputations of the extremity. The proposed system for evaluation of the condition and scope of the combined treatment resulted in decrease of mortality among operated patients from 14.7% to 9.8% and among not operated ones--from 20.5% to 5.5%. The suggested classifications of complicated forms of the "diabetic foot" syndrome provided proper evaluation of the prognosis and individual approach to the choice of treatment measures. 相似文献
5.
The problem of diffusion-controlled growth following an instantaneous nucleation event was studied within the framework of a new numerical model, considering the spatial distribution of hemispherical nuclei on the electrode surface and the mutual influence of growing nuclei via the collision of 3D diffusion fields. The simulation of the diffusion-controlled growth of hexagonal and random ensembles was performed at the overpotential-dependent number density of nuclei. The diffusion flow to each nucleus within a random ensemble was simulated by the finite difference method using the derived analytical expressions for the surface areas and the volumes formed at the intersection of 3D diffusion fields with the side faces of a virtual right prism with a Voronoi polygon base. The implementation of this approach provides an accurate calculation of concentration profiles, time dependences of the size of nuclei, and current transients. The results, including total current density transients, growth exponents, and nucleus size distribution, were compared with models developed within the concept of planar diffusion zones, the mean-field approximation and the Brownian dynamics simulation method, as well as with experimental data from the literature. The prospects of the model for studying the initial stages of electrocrystallization were discussed. 相似文献
6.
Yuriy Y Kulyabin Alexey V Voitov Nataliya R Nichay Ilya A Soynov Alexey V Zubritskiy Alexander V Bogachev-Prokophiev 《Interactive Cardiovascular and Thoracic Surgery》2022,35(2)
Open in a separate window OBJECTIVESThe appropriate approach for surgical repair of coarctation of the aorta with a ventricular septal defect (VSD) remains controversial. This study evaluated the outcomes of primary repair of VSDs with periventricular device closure without cardiopulmonary bypass through a left thoracotomy in patients without arch hypoplasia.METHODSWe selected 21 patients aged <1 year, including 7 neonates, who underwent repair of coarctation of the aorta with periventricular device closure of a VSD.RESULTSThe median occluder size was 6 (range, 5–8) mm. The median mechanical ventilation time was 14 (range, 2–68) h, and the median duration of hospital stay was 11 (range, 7–16) days. No reoperations were required to correct VSD shunting, and the median residual shunt size was 1 (range, 1–2) mm. The median follow-up period was 13 (range, 4–31) months. No late deaths were reported, and no haemodynamically significant pressure gradient at the anastomotic site was observed. The median distal aortic arch z-score was 0.39 (range, −0.1–to 0.9). Only 1 patient had a permanent pacemaker implanted towards the end of the follow-up period.CONCLUSIONSPeriventricular device closure can be used safely for closure of VSD in children with coarctation of the aorta without a hypoplastic aortic arch, even in neonates, to reduce the risk of prolonged cardiopulmonary bypass. This hybrid approach can be performed with a low incidence of rhythm disturbances and residual shunting. However, a meticulous assessment of the VSD anatomy is essential to avoid any unfavourable events. 相似文献
7.
Rybakov GS Dibirov MD Briskin BS Khalidov OKh Barsukov MG Prosperov MA Kuznetsova MA Mikhaĭlin AA Ramazanova IuI Larichev DV Kuz'mina ID 《Khirurgiia》2008,(4):20-26
The analysis of diagnostics and treatment of 602 patients with destructive pancreatitis has shown that definition of etiological and pathogenetic forms of pancreatitis defines strategy of treatment. In this way, patients with biliary pancreatitis require emergency operative treatment with use of endoscopic interventions without dependence from a stage of disease. To patients with alcoholic or alimentary pancreatitis in the stage of enzymatic toxemia conservative treatment should be spent only, until shock and/or delirium won't be reduced. Endoscopic retrograde cholangiopancreatography + endoscopic papillosphincterotomy with concrement removal from common bile duct--is the operation of choice in case of acute biliary pancreatitis at the first stage. Laparoscopic cholecystectomy is the operation of choice at the second stage of disease. At destructive pancreatitis of other origin in a stage of the infection or necrotic suppurative inflammation use of open and closed small invasive methods of intervention is most proved. Given tactics of treatment has allowed to lower severity of clinical course, frequency of complications and lethality. 相似文献
8.
9.
Mucosal addressin cell adhesion molecule (MAdCAM-1) plays a pivotal role in T-lymphocyte homing to the gut. Given the strong association between the autoimmune liver diseases primary sclerosing cholangitis and autoimmune hepatitis and inflammatory bowel disease, we investigated the role of MAdCAM-1 in recruiting mucosal lymphocytes to the liver. MAdCAM-1 was strongly expressed on inflamed portal vein/sinusoidal endothelium in autoimmune mediated liver disease. In modified Stamper-Woodruff assays, MAdCAM-1 on hepatic vessels supported adhesion of alpha4beta7+ lymphocytes (i.e., gut-derived T cells) from patients with inflammatory bowel disease and primary sclerosing cholangitis. This adhesion was inhibited by pretreatment with blocking antibodies to MAdCAM-1, alpha4beta7, or the integrin alpha4 chain indicating that MAdCAM-1 in inflamed liver is functionally active. Circulating lymphocytes from patients with primary sclerosing cholangitis showed rolling adhesion on MAdCAM-1 transfectants in a flow-based adhesion assay that could be blocked by anti-MAdCAM-1 or anti-alpha4beta7 mAbs. These findings indicate that, under certain circumstances, vessels in the human liver support adhesion of alpha4beta7+ mucosal lymphocytes via binding to aberrantly expressed MAdCAM-1 on liver endothelium. This provides a mechanism to explain the hepatic recruitment of mucosal lymphocytes in inflammatory liver disease complicating inflammatory bowel disease. 相似文献
10.
Cholesterol feeding reduces nuclear forms of sterol regulatory element binding proteins in hamster liver 下载免费PDF全文