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NN Belosel''ski? OB Ershova IuN Pribytkov AV Bessarab 《Canadian Metallurgical Quarterly》1997,69(5):55-58
To specify shape of the vertebra in relation to age and sex, the authors studied roentgenomorphometric evidence upon examination of the thoracic and lumbar spine in 600 patients over 50. Vertebral deformities were found in 45.1 and 44.5% of the examined males and females, respectively. Changes corresponding to vertebral body fracture were recorded in 12.3% of the males and 15.3% of the females. Age-related trends in the frequency of various defects have been analyzed. The frequency differed in males and females. 相似文献
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This article takes lactose intolerance as a topic for exploring clashes of power, authority, and knowledge in clinical interactions and interpretations of laywomen. In clinics providing maternal and child care, staff and clients jointly produced authoritative knowledge, most often a version of biomedicine. The Euroamerican staff tended to give advice that was biologically appropriate for them but not for many of their patients, a process reflecting what we refer to as biocentrism. Resulting information given to pregnant and lactating women and diagnoses of children's growth patterns were inappropriate in some cases, with potentially serious legal and health implications. Clinic staff often unwittingly ignored the efforts of their clients to begin a discussion of discrepancies between their bodily knowledge and clinic advice. Some women created their own syntheses, which supported the ascendancy of biomedical knowledge but were not in the interests of their own health. 相似文献
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The authors of the present article were the first to work out theoretical foundations and methods of physiological diagnosis of neurocirculatory dystonia. Criteria of tension of myocardial functional structures and central regulatory mechanisms have been identified both in healthy subjects and cardiological patients. It has been ascertained that degree and systematic character of tension cause the physiological risk factors for cardio-pathology to develop, 6 types were identified of loading adaptation of the heart caused by extent of its tension, in individuals with neurocirculatory dystonia. Each of the types disclosed is characterized by a dynamics of the functional volumes proportions as well as by peculiarities of the adaptation mechanisms. Physiological diagnosis of functioning of the heart is one of major methods of the primary prophylaxis of neurocirculatory dystonias as well as prevention of aggravation of their course. 相似文献
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AV Demin AV Kolesnikov MA Olfer'ev PV Favorov KV Fegeding AG Gabibov NV Gnuchev 《Canadian Metallurgical Quarterly》1998,34(10):1333-1337
A new system for the expression of a catalytic light chain antibody to the vasoactive intestinal peptide is described. The system made possible the isolation the large amounts of a homogeneous protein without any additional peptide domains. The preparation obtained can be used in further experiments on light chain crystallization and in X-ray-structural analysis of its catalytic center. 相似文献
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AV Goriunova GV Kozlovskaia IA Kozlova NV Rimashevskaia NIu Savvateeva GN Shimonova 《Canadian Metallurgical Quarterly》1996,96(4):46-50
Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children. 相似文献
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SH Willis AH Rux C Peng JC Whitbeck AV Nicola H Lou W Hou L Salvador RJ Eisenberg GH Cohen 《Canadian Metallurgical Quarterly》1998,72(7):5937-5947
Previously, we showed that truncated soluble forms of herpes simplex virus (HSV) glycoprotein D (gDt) bound directly to a truncated soluble form of the herpesvirus entry mediator (HveAt, formerly HVEMt), a cellular receptor for HSV. The purpose of the present study was to determine the affinity of gDt for HveAt by surface plasmon resonance and to compare and contrast the kinetics of an expanded panel of gDt variants in binding to HveAt in an effort to better understand the mechanism of receptor binding and virus entry. Both HveAt and gDt are dimers in solution and interact with a 2:1 stoichiometry. With HveAt, gD1(306t) (from the KOS strain of HSV-1) had a dissociation constant (KD) of 3.2 x 10(-6) M and gD2(306t) had a KD of 1.5 x 10(-6) M. The interaction between gDt and HveAt fits a 1:1 Langmuir binding model, i.e., two dimers of HveAt may act as one binding unit to interact with one dimer of gDt as the second binding unit. A gD variant lacking all signals for N-linked oligosaccharides had an affinity for HveAt similar to that of gD1(306t). A variant lacking the bond from cysteine 1 to cysteine 5 had an affinity for HveAt that did not differ from that of the wild type. However, variants with double cysteine mutations that eliminated either of the other two disulfide bonds showed decreased affinity for HveAt. This result suggests that two of the three disulfide bonds of gD are important for receptor binding. Four nonfunctional gDt variants, each representing one functional domain of gD, were also studied. Mutations in functional regions I and II drastically decreased the affinity of gDt for HveAt. Surprisingly, a variant with an insertion in functional region III had a wild-type level of affinity for HveAt, suggesting that this domain may function in virus entry at a step other than receptor binding. A variant with a deletion in functional region IV [gD1(Delta290-299t)] exhibited a 100-fold enhancement in affinity for HveAt (KD = 3.3 x 10(-8) M) due mainly to a 40-fold increase in its kinetic on rate. This agrees with the results of other studies showing the enhanced ability of gD1(Delta290-299t) to block infection. Interestingly, all the variants with decreased affinities for HveAt exhibited decreased kinetic on rates but only minor changes in their kinetic off rates. The results suggest that once the complex between gDt and HveAt forms, its stability is unaffected by a variety of changes in gD. 相似文献