21世纪的耐火材料——动态高技术复合材料

从高技术复合材料的发展前景阐述了钙铝酸盐水泥结合浇注料和MgO-C砖这两类现代耐火材料。这些材料不仅是典型的尖端多相复合材料,而且显示了其他复合材料中难以见到的动态特性。讨论了产生这一特性的某些动力学因素。得到的结论是:当用复合材料这个术语描述这些耐火材料的某些方面时,动态特性又增加了一层复杂性。     

Conceptual approaches to the diagnosis of stress-induced functional disorders in humans under conditions of industrial activity

In accordance with the fundamental concept of the systems symmetrical approach, a model of the body's "ideal functional status" and a polyparametric method for diagnosing the human functional status (the method has been patented in Russia) were developed, on the basis of the unified set of amplitude and time parameters of a complex of physiological parameters (ECG, etc.). The systems symmetrical approach is basically new in defining the ratio of harmonic parameters acting as new diagnostic evidence for the health status. The unchanging ratio of parameters of autovariation processes in the cardiac, vascular, and respiratory systems, their changes in the development of the adaptative syndrome and the value were examined in healthy individuals at rest and during exercise an intensive productive activity (point brazing at a plant of electron devices), and in the trainees. It was demonstrated that the mechanism of development of adaptative processes was associated with the synchronization of autovariations in the cardiorespiratory and vascular systems and the involution of adaptative processes, their break, depletion, i.e. stress, were determined by the imbalance of relationships and the desynchronization of autovariations in these systems. To define a set of cardiorespiratory and hemodynamic parameters is necessary, but insufficient to evaluate (diagnose) the health status and health-disease intermediate diseases (stress and adaptative overtension). The ratio harmonicity of these parameters, i.e. well-balanced relations between the subsystems is the main characteristic. The assessment of the human health status in terms of the reference-the model of the ideal status as the ideal health status without using the complex and indefinite concept of the normal and moderate health status-is conceptual for polyparametric status estimation.     

Analysis of apoptosis during hair follicle regression (catagen)

Keratinocyte apoptosis is a central element in the regulation of hair follicle regression (catagen), yet the exact location and the control of follicular keratinocyte apoptosis remain obscure. To generate an "apoptomap" of the hair follicle, we have studied selected apoptosis-associated parameters in the C57BL/6 mouse model for hair research during normal and pharmacologically manipulated, pathological catagen development. As assessed by terminal deoxynucleotide transferase dUTP fluorescein nick end-labeling (TUNEL) stain, apoptotic cells not only appeared in the regressing proximal follicle epithelium but, surprisingly, were also seen in the central inner root sheath, in the bulge/isthmus region, and in the secondary germ, but never in the dermal papilla. These apoptosis hot spots during catagen development correlated largely with a down-regulation of the Bcl-2/Bax ratio but only poorly with the expression patterns of interleukin-1beta converting enzyme, p55TNFR, and Fas/Apo-1 immunoreactivity. Instead, a higher correlation was found with p75NTR expression. During cyclophosphamide-induced follicle dystrophy and alopecia, massive keratinocyte apoptosis occurred in the entire proximal hair bulb, except in the dermal papilla, despite a strong up-regulation of Bax and p75NTR immunoreactivity. Selected receptors of the tumor necrosis factor/nerve growth factor family and members of the Bcl-2 family may also play a key role in the control of follicular keratinocyte apoptosis in situ.     

Vasoactive properties of various fragments of human alpha-calcitonin gene-related peptide

Effects of some fragments of alpha-calcitonine gene-related peptide (alpha-CGRP) on the collector lymphatic vessels of the rat small intestine mesenterium, were studied. All the fragments excepting alpha-CGRP (21-24) and (21-31) activate motility of the lymphatic vessels enhancing phasic contractions of the walls. Presence of aminoacid residuals in the 20-29 area is "critical" for realising vasoactive properties by these fragments.     

Comparative study of active site structure in bovine and Pacific salmon trypsins

The kinetic investigation was carried out on the inhibition of hydrolysis of N, alpha-benzoyl-D, L-arginine-p-nitroanilide (BApNA) for bovine and salmon trypsin by phenylmethanesulphonyl fluoride (PMSF), N, alpha-tosyl-L-lysine chloromethyl ketone (N-TLCK), N, alpha-tosyl-L-phenylalanine chloromethyl ketone (N-TPCK). Kinetic parameters of inhibition (Ki, k2) by PMSF for salmon and bovine trypsin differ insignificantly. The k2/Ki value of N-TPCK for salmon trypsin is 10 times more than of bovine trypsin. Kinetic parameters of inhibition by N-TLCK had the less difference. The Ki value of this inhibitor for salmon trypsin is 5 times less than that of bovine trypsin and k2 value is 1.7 times less.     

Immunological indicators in patients with pulmonary tuberculosis in the presence of drug-resistant Mycobacteria

Immunological indices for 121 pulmonary tuberculosis (PT) patients discharging drug-resistant M. tuberculosis were compared to those for 87 PT patients with M. tuberculosis sensitive to antibacterial drugs. The patients with drug-resistant bacteria before hospitalization had lower count of T-lymphocytes, altered proportion T-helpers/T-suppressors, reduced ability of T-lymphocytes for blast transformation in the presence of PHA and PPD. T-lymphocyte functional activity remained inhibited as compared to those patients discharging drug-sensitive mycobacteria.     

The effect of catalase inhibitor 3-amino-1,2,4-triazole on coupled oxidative phosphorylation and the state of adenyl system in liver mitochondria of albino rats

Blepharoptosis is a recognized complication of cataract extraction and other ocular procedures. A 6-month waiting period is recommended before repairing postcataract ptosis because most cases resolve during this time. We report the course of a patient who developed spontaneous recovery of eyelid function 11 months after cataract surgery. She had previously undergone successful ptosis repair 8 months after cataract extraction, but developed overcorrection 3 months later as her levator function returned to normal. We recommend at least a 1-year waiting period before repair of postcataract ptosis. If corrective surgery is undertaken earlier than 1 year due to visual obstruction or for aesthetic reasons, we suggest two guidelines. The levator should be plicated rather than resected and patients should be forewarned of the possibility for a revisionary procedure if spontaneous return of levator function occurs.     

The diagnostic and treatment characteristics of focal liver lesions using computed tomography

Under analysis is an experience with examining and treatment of 167 patients with focal lesions of the liver using computed tomography. Percutaneous transhepatic puncture and draining the hepatic abscesses and cysts under control of computed tomography is an independent method of treatment used in 53 patients. The technique of performing the puncture and drainage is described. Specific features of surgical treatment of focal lesions of the liver are described. Decompression of bile ducts in the postoperative period is shown to be necessary. A conclusion is made about high efficiency of computed tomography in diagnosis and treatment of focal lesions of the liver.