Structural levels of fatigue failure and damage estimation in 17Mn1Si steel on the basis of a multilevel approach of physical mesomechanics

The evaluation of crack initiation and growth at microscopic scale is a crucial issue for the safety assessment of macroscopical fractures. In the present paper, the crack propagation in 17Mn1Si steel macroscale is investigated by taking into account the microstructural damage accumulation in polycrystalline solids. The revealed regularities are in good agreement with the concept of physical mesomechanics, which allows obtaining a generalized view of the material deformation and the failure process in the vicinity of the concentrator, which fulfills the limiting, initial and physical conditions and allows obtaining the generalized regularities in deformation and failure of 17Mn1Si steel.     

The treatment of patients with benign prostatic hyperplasia using the selective alpha-blocker alfuzosin

40 patients with benign prostatic hyperplasia (BPH) were treated with the alpha-blocker alfuzosin which was administered per os twice a day in a dose 5 mg. The treatment brought about a decrease of the mean symptom score from 19.6 to 12.2, of quality of life from 5.2 to 2.1, of residual urine from 152 to 82 ml. Mean and maximal urinary flow rates rose by 35 and 45%, respectively. The level of prostate-specific antigen over the treatment course did not change. The findings of the trial evidence for high efficacy of alfuzosin in the treatment of urination disorders in BPH patients.     

Role of electric stimulation of the heart during selective contrast examination of the coronary arteries with the use of the data of continuous recording of the bundle of His potentials and arterial pressure

The frequency of disorders of the cardiac rhythm during injection of a contrast medium into the coronary vessel under different conditions was studied in 214 patients. Atropine premedication was applied as a preventive factor in 142 patients, atrial stimulation in 60, and both factors simultaneously in 12. In 10 patients a single injection of the contrast medium was performed without preventive measures. In 20 patients the changes were studied by recording the potentials of the bundle of His and the arterial pressure. On the basis of the bundle of His ECG data it is concluded that atropine and atrial stimulation produce an effect on individual links of the complex mechanism underlying the effect of the contrast medium on the cardiac conduction system.     

Effect of modulators of energy metabolism on cyclophosphane toxicity for Daphnia magna]

BACKGROUND: The purpose of this study was to determine cost of care for leg ulcers in sickle cell patients and suggest an improved modality in ulcer care. STUDY DESIGN: We performed a retrospective study of a group of sickle cell disease patients with leg ulcers. RESULTS: Eighteen patients with a leg ulcer (duration: mean, 53.7 months), sickle cell disease, and a mean of 20.7 years of age had various modalities of treatment with the only consistency in healing being a commercial moist-wound dressing. CONCLUSIONS: There is no consistency in the treatment of the sickle cell patient with a leg ulcer. Treatment with a moist dressing had the best results.     

Comparative characteristics of various types of operations performed in treatment of diffuse colonic polyposis

Diffuse polyposis of the large intestine characterized by the development of multiple polyps in it and their subsequent malignant degeneration is one of the most severe disease of the gastrointestinal tract. That it must be treated by surgery needs no proof. However, the volume and the character of the surgical intervention on the large intestine is still a debatable problem. The article discusses the experience in the follow-up of 445 patients for periods of 12 months to 30 years after operation for diffuse polyposis. In 228 patients various segments of the large intestine which were free from polyps were not resected. During these follow-up periods malignant tumors developed in the preserved parts of the large intestine in 10.1% patients and intensive growth of polyps was encountered in 3.5% of patients. The frequency of carcinoma development depended significantly less on the length of the follow-up period and much more on the character of affection of the preserved parts of the large intestine with the polyps.     

The use of a new strain of Vibrio cholerae O139 as a producer of an enteric chemical vaccine

Amalgam remains unchallenged as a posterior restorative material. But its inability to bond to the teeth leads to some amount of microleakage at the restoration-tooth interface with associated problems such as post operative sensitivity, pulpal complications etc. Also a broken amalgam restoration requires replacement which will further weaken the tooth structure. Recently, 4-META has been introduced which can graft amalgam and composite to enamel, dentin and old amalgam restorations. In this study, the bonding and marginal sealing abilities of 4-META was assessed both at the tooth-amalgam interface and old amalgam fresh amalgam interface.     

The kinetics of sodium channel inactivation in the sensory neurons depends on the type of hydrogen ion buffer

The kinetics of inactivation of TTX-sensitive and TTX-resistant sodium channels in the excitable membrane of rat dorsal root ganglion cells were studied using whole-cell recording technique with the presence of two different pH buffers, Tris and Hepes. It is shown that Tris ions irreversibly interact with inactivation system, accelerating the decaying phase of sodium current. The buffer regulates the gating machinery of two types of the channels. It makes the second order properties more pronounced. On the contrary, the characteristics of inactivation process in Hepes are more close to that we register immediately after the rupture of the cell membrane. We suppose that Hepes buffer is more adequate for investigation of sodium channel inactivation processes.