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81.
The death from acute ischemic heart diseases (acute coronary insufficiency (n = 39) and acute myocardial infarction (n = 36) is accompanied by a slight increase in the thickness of the left ventricular wall with preserved normal heart weight. Microscopically, there are longer intermuscular distances, cardiomyocytic thickening, nuclear polymorphism, contractures, and destruction of myocytes and their lysis.  相似文献   
82.
The Fus1 gene resides in the critical 3p21.3 human chromosomal region deleted in lung and breast cancers. Recently, the tumour suppressor properties of Fus1 were confirmed experimentally by intra-tumoural administration of Fus1 that suppressed experimental lung metastasis in mice. We generated Fus1-deficient mice that were viable, fertile, and demonstrated a complex immunological phenotype. Animals with a disrupted Fus1 gene developed signs of autoimmune disease, such as vasculitis, glomerulonephritis, anaemia, circulating autoantibodies, and showed an increased frequency of spontaneous vascular tumours. Preliminary analysis of immune cell populations revealed a consistent defect in NK cell maturation in Fus1 null mice that correlated with changes in the expression of IL-15. Injection of IL-15 into Fus1 knockout mice completely rescued the NK cell maturation defect. Based on these results, we propose the hypothesis that Fus1 deficiency affects NK cell maturation through the reduction of IL-15 production but does not directly alter their developmental capacity. Since acquired immunity was not affected in Fus1-deficient animals, we suggest a relationship between the Fus1 protein and the regulation of innate immunity via IL-15 production. The increased frequency of spontaneous cancers and the development of an autoimmune syndrome in Fus1 null mice imply that these mice could serve as a model for studying molecular mechanisms of anti-tumour immunity and autoimmunity.  相似文献   
83.
84.
AIM: To investigate whether smoking has a differential effect by Pro198Leu genotypes of the glutathione peroxidase-1 (GPx1) gene on the risk of bronchial asthma (BA) in Russian population. MATERIAL AND METHODS: DNA samples from 195 asthmatics and 167 healthy volunteers were genotyped for Pro198Leu polymorphism of the GPx1 gene by polymerase chain reaction and restriction fragment length analysis. RESULTS: Smoking was significantly associated with an increased risk of non-allergic BA in males but not in females (p < 0.00001). When smoking was examined according to Prol98Leu polymorphism of the GPx1 gene, association of 198Pro/Leu genotype with susceptibility to allergic BA was found only in male smokers (odds ratio = 2.51, 95% confidence interval = 1.04 to 6.06, p = 0.04). CONCLUSION: The risk of allergic BA associated with smoking is increased in males who are heterozygous carriers for the low-activity 198Leu allele of the glutathione peroxidase-1 gene. The importance of molecular mechanisms is shown by which functional variants of antioxidant defense genes may mediate potentially oxidative effects of tobacco smoke on asthmatic phenotype.  相似文献   
85.
A hundred patients operated on under extracorporeal circulation (EC) with bicaval cannulation in the moderate general hypothermia mode were intraoperatively examined. According to the used cardioplegic solution, all the patients were divided into three groups: 1) Konsol; 2) Konsol MF; 3) St. Thomas (a control group). All the groups were matched by age, gender, the duration of myocardial ischemia (MI) (37-128 min), that of EC (52-186 min), and the nature of surgical interventions, of which mitral valve replacement amounted to 72-78%. To prepare a modified solution, 20 ml of 40% glucose, 20 units of insulin, and 200 mg of creatine phosphate (Neoton) were added to a flask containing 400 ml of Konsol. The efficiency of myocardial protection was evaluated by the data characterizing cardiac arrest and cardiac performance resumption, as well as by heart rate and the use of inotropic support in the reperfusion period. The parameters of central hemodynamics and systemic coronary blood flow, the concentrations of glucose and lactate, the blood gas and electrolyte composition of the coronary sinus (CS), myocardial oxygen consumption and the oxygen-utilizing coefficient were monitored. The cardioplegic solutions Consol and Consol MF were found to have a more effective cardioprotective activity in patients with cardiac valvular disease, operated on under EC and moderate hypothermia that St. Thomas'solution. Modification of the Consol solution by adding glucose, creatine phosphate, and insulin improves the protective effect of the solution, promoting a rapider transition of the myocardium from anaerobic to aerobic metabolism.  相似文献   
86.
Twenty-five full-term neonates with severe posthypoxic syndrome, including 9 (36%) with prior acute moderate asphyxia, 8 (32%) with acute asphyxia, and 8 (32%) with associated acute asphyxia, were examined. The severity of posthypoxia and the efficiency of its treatment were evaluated, by studying cerebral and systemic hemodynamics. In children with moderate and severe asphyxia, artificial ventilation contributed to normalization of acid-base balance and infusion of dopamine in a dose of up to 5 microg/kg x min could achieve adequate cardiac output. In children with associated severe asphyxia, infusion of dopamine in a dose of 5.5-10 microg/kg x min, which failed to improve cerebral perfusion pressure, was required to maintain the optimal cardiac output. This situation requires additional cerebral protective therapy aimed at lowering intracranial pressure.  相似文献   
87.

Introduction

The optimal treatment of high energy tibial fractures remains controversial and a challenging orthopaedic problem. The role of external fixators for all these tibial fractures has been shown to be crucial.

Methods

A five-year consecutive series was reviewed retrospectively, identifying two treatment groups: Ilizarov and Taylor Spatial Frame (TSF; Smith & Nephew, Memphis, TN, US). Fracture healing time was the primary outcome measure.

Results

A total of 112 patients (85 Ilizarov, 37 TSF) were identified for the review with a mean age of 45 years. This was higher in women (57 years) than in men (41 years). There was no significant difference between frame types (p=0.83). The median healing time was 163 days in both groups. There was no significant difference in healing time between smokers and non-smokers (180 vs 165 days respectively, p=0.07), open or closed fractures (p=0.13) or age and healing time (Spearman''s r=0.12, p=0.18). There was no incidence of non-union or re-fracture following frame removal in either group.

Conclusions

Despite the assumption of the rigid construct of the TSF, the median time to union was similar to that of the Ilizarov frame and the TSF therefore can play a significant role in complex tibial fractures.  相似文献   
88.
High-temperature superconducting (HTS) bulks can be used in electrical applications. Experimental characterization of large-size HTS bulks is a tricky issue. The relevant parameters for their application were directly measured in this study. This paper has three main aims. Firstly, features of YBaCuO bulks are presented. Secondly, an electrical motor application is developed using magnetic field shielding and trapping. Thirdly, the HTS bulks are characterized. Several classical methods were used, which are mainly magnetic methods only available for small samples. The complete penetration magnetic field and the critical current density were found to be the main parameters relevant for applications. An innovative entire HTS bulk characterization method is presented. This characterization method is useful for end users and engineers to better implement HTS bulks.  相似文献   
89.
Some methodical problems are discussed that are of practical importance for the performance of transvenous endocardial pacing of the heart in patients with acute myocardial infarction in whom the clinical course is complicated by an atrio-ventricular block. Some results of the employment of this method in 66 cases of acute myocardial infarction are presented. A set of criteria is suggested for controlling the proper position of the probe in the cardiac cavity, the most important approaches for the introduction of the probe are described, as well as the main reasons of ineffective cardiac pacing and its most common complications.  相似文献   
90.
The effect of nondamaging intensity laser irradiation on the immune system   总被引:4,自引:0,他引:4  
Data on in vitro studies of the effect of nondamaging laser irradiation on peripheral blood lymphoid cells of donors and cancer patients are reported including the results of experimental investigations carried out in patients with breast cancer and malignant melanoma. Laser irradiation is demonstrated to potentiate the immunological parameters both in healthy individuals and patients, the effect being more marked in cancer patients. A different action of red and blue laser irradiation on the immune system was revealed. The evidence obtained may be useful in working out the immunotherapeutic methods in cancer management.  相似文献   
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