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1.
Injection of ozonized normal saline to animals with transplanted sarcoma-45 normalized energy metabolism in the liver, which is important for this organ's function under conditions of malignant growth. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 207–209, August, 1998  相似文献   
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The comparative study of HIV-positive and clinically healthy persons has indicated that the antigens of M. pneumoniae, M. fermentans and U. urealyticum are encountered nearly twice more frequently in the blood of HIV-infected patients than in that of healthy individuals. Mycoplasma antibodies are detected in HIV-positive persons 12 times more frequently than in healthy ones. Among the HIV-infected persons there are those who have simultaneously antigens of some Mycoplasma species.  相似文献   
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Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
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Age-associated endocrine dysfunctions and approaches to their correction   总被引:2,自引:0,他引:2  
This review discusses age-specific functional changes in different components of the endocrine system (pituitary, epiphysis, adrenals, and gonads), their role in aging and age-specific diseases, and possible approaches to correction of endocrine disorders and prevention of accelerated aging.  相似文献   
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The study was aimed at characterizing the changes in hypothalamic-pituitary-adrenal (HPA) axis function during aging in monkey models (Papio hamadryas and Macaca mulatta). It has been established by specific radioimmunoassay and enzyme immunoassay that basal plasma levels of adrenal androgenes (dehydroepiandrosterone-DHEA, dehydroepiandrosterone sulfate-DHEAS) and the early precursors of steroid hormones (pregnenolone and 17-hydroxypregnenolone) progressively decrease with age in baboons and macaques, while cortisol and 11-desoxycortisol concentrations do not change. The old female rhesus monkeys exhibited a higher cortisol and corticosterone response, but a lower DHEAS response to corticotropin-releasing hormone (CRH) administration then the young monkeys. The aged rhesus monkeys also exhibited a decrease of the adrenal cortex resiliency, that was manifested in the deceleration of the decrease of cortisol concentrations after the peak values had been reached in response to ACTH 1-39 administration. At the same time the ACTH 1-24 depot test revealed no age-related changes in the maximum capacity of monkey adrenals to synthesize and secrete cortisol. The aged monkeys also developed less sensitivity of the HPA axis to dexametasone suppression test. The age-related hormonal changes may play an important role in the age-related involutive processes and in the disorders of the adaptive ability of old organisms.  相似文献   
9.
Fluctuations of the thiol disulfide system were shown to be interrelated with changes in the ECG indices. Trimetazidine since it has antioxidant properties was found to be effective in patients with low thiol disulfide ratios. A single dose of 0.8 mg/kg of the body mass was shown to inhibit the appearance of stress-dependent ischemic symptoms during surgical procedures.  相似文献   
10.
The optic nerve and mesencephalic optic centre (tectum opticum, TO) of the tortoise, Testudo horsfieldi, Gray, in the norm and after the enucleation have been studies using Golgi's method, electron microscopy and the electrophysiological technique. The optic nerve comprises about 400,000 fibres represented by two classes of axons: myelinated (10%) and unmyelinated (90%). The diameters of the former vary within 0.3-3 mum, of the latter within 0.3-1.1 mum. The neurogramms of the optic nerve contain two components corresponding to the two rates of conduction through different groups of fibres (1.3 musec and 0.5 musec). The stratified synaptic organization of the TO has been investigated. The optic terminals are shown to join in complex synaptic formations at certain levels of the upper layers of the TO (Strata I, II and III). The process of degeneration in the optic system of Testudo is drastically stretched in time. It was demonstrated by the electrophysiological control that the TO potentials induced in response to the nerve stimulation were not registered any longer only 6-6.5 months after the enucleation. Certain groups of retinal fibres of the optic nerve and their terminals in the TO are shown to degenerate differently and asynchronously. Earlier unknown types of destructive changes of the terminals (vesicular, neurofilamentous, glycogen and others) are described. It is suggested that the different types of degeneration of the optic fibres and their terminals are the result of possible biochemical heterogeneity of the retinal ganglious cells. The comparison of the terms and types of degeneration of different groups of nervous fibres in the optic nerve and their terminals in the TO has revealed some correlations suggesting that the myelinated optic fibres produce nervous terminals degenerating by the "dark" type, whereas the unmyelinated optic axons may be subdivided into several groups, each producing nervous terminals subjected to a definite type of destruction ("clear", "vesicular", "neurofilamentous" etc.). The localization of certain groups of therminals at certain levels of the cortical plate of the TO confirms the electrophysiological data on the stratified organization of the retino-tectal projections in the TO of lower vertebrates. It has been shown by the comparison of the results obtained with those reported for Emys orbicularis, L. that the two species have marked differences in the morpho-functional characteristics of the retino-tectal system, neuronic composition of the TO, the character of destructive changes of the terminals after the enucleation and the component composition of polysynaptic complexes and glomerules. Probably these differences may come from the peculiarities of the perception and transformation of visual information in the species.  相似文献   
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