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81.
In 63 children with severe meningococcal infection (MI) and meningitides of another origin red cell metabolism was studied: levels of ATP, ADP, AMP, ATP/ADP, ATP/AMP, energetic charge, 2,3-DPG, FAD, piruvate, lactate, activity of lactate dehydrogenase, piruvate kinase, glucose-6-phosphate dehydrogenase, glutatione reductase, Mg2+, Na+, K(+)-dependent ATPase. All the disease periods were characterized by combined pathobiochemical shifts of different degree typical for varying metabolic systems and correlating with the infection severity. The discussion covers pathogenetic and clinical significance of red cell metabolism shifts in patients with MI and purulent meningitides.  相似文献   
82.
OBJECTIVES: This study investigated effects of acute plasma volume expansion on plasma levels and urinary output of two endogenous Na,K-ATPase inhibitors, marinobufagenin-like and ouabain-like immunoreactive substances. METHODS: Plasma volume was expanded for 3 h via intravenous saline infusion in three groups of anesthetized dogs--nontreated (n = 5); pretreated with rabbit antidigoxin (n = 5); and pretreated with rabbit antimouse (control) antibody (n = 4). RESULTS: Plasma marinobufagenin-like immunoreactivity increased to 11.87 +/- 3.16 nmol.l-1 (vs. 0.30 +/- 0.16 nmol.l-1) within 10 min of volume expansion, in parallel with a 15% increase in LVdP/dt, then decreased to 2.21 +/- 0.59 nmol.l-1, and in 90 min increased to 11.8 +/- 2.8 nmol.l-1, in parallel with the maximal natriuretic response. Plasma concentrations of ouabain-like immunoreactive material were increased after 90 min of saline infusion (0.019 +/- 0.004 nmol.l-1 vs. 0.139 +/- 0.056 nmol.l-1). Pretreatment of the animals with antidigoxin antibody blocked the positive inotropic and reduced natriuretic response to volume expansion, and decreased the urinary release of marinobufagenin-like, but not ouabain-like, material. CONCLUSIONS: These results show the presence of marinobufagenin-like immunoreactive substance in dog plasma and suggest that mammalian EDLF may have a bufodienolide nature. Endogenous marinobufagenin-like immunoreactive substance, which is likely to cross-react with antidigoxin antibody, is involved in the natriuretic and positive inotropic responses to plasma volume expansion.  相似文献   
83.
A medical genetic study of Orshanskii, Morkinskii, Sovetskii, and Semurskii raions (districts) of the Marii El Republic was performed. The total number of subjects examined was 115,743. Meadow Maris and Russians accounted for the most part of the populations of the districts studied. A total of 147 families with presumably autosomal dominant (AD) pathology and 150 families with presumably autosomal recessive (AR) or X-linked pathology (270 and 169 affected persons, respectively) were revealed. Segregation analysis demonstrated a good agreement between the observed and expected segregation frequencies for both AR and AD diseases, as well as a considerable number of sporadic cases of presumably AD diseases. The incidence of hereditary diseases was estimated separately for different population groups. Significant differences in this incidence were revealed between the urban and rural, as well as between the Russian and Mari populations; the average incidence was 2.33 affected subjects per 1000 people. The incidence of AR diseases was significantly higher in Maris than in Russians (1.34 x 10(-3) and 0.82 x 10(-3), respectively). The populations studied exhibited a significant, high correlation between the incidence of AR diseases and the levels of random and local inbreeding. The incidence of X-linked recessive diseases was approximately the same as in Russian populations studied earlier. Its average value was 0.5 per 1000 men; the incidence in the Mari and Russian populations did not differ significantly. The higher AD incidence in the total population studied and the higher AR incidence in the Meadow Mari population compared to the populations studied earlier are discussed.  相似文献   
84.
Rapid progress in effective methods to image brain functions has revolutionized neuroscience. It is now possible to study noninvasively in humans neural processes that were previously only accessible in experimental animals and in brain-injured patients. In this endeavor, positron emission tomography has been the leader, but the superconducting quantum interference device-based magnetoencephalography (MEG) is gaining a firm role, too. With the advent of instruments covering the whole scalp, MEG, typically with 5-mm spatial and 1-ms temporal resolution, allows neuroscientists to track cortical functions accurately in time and space. We present five representative examples of recent MEG studies in our laboratory that demonstrate the usefulness of whole-head magnetoencephalography in investigations of spatiotemporal dynamics of cortical signal processing.  相似文献   
85.
1. Pulmonary surfactant is a mixture of lipids and proteins that lines the air-liquid interface of the lungs of all vertebrates. In mammals, it functions to reduce and vary surface tension, which helps to decrease the work of breathing, provide alveolar stability and prevent alveolar oedema. The present review examines the evolution and relative importance of these surface activity related functions in the lungs of vertebrates. 2. The surface activity of surfactant from fish, amphibians, birds and most reptiles is generally very low, correlating with a low body temperature and a low disaturated phosholipid content of their surfactant. In contrast, the surfactant of those reptiles with a higher preferred body temperature, as well as that of birds and mammals, has a much higher surface activity. 3. The two main functions of surfactant in mammals are to provide alveolar stability and to increase compliance of the relatively stiff bronchoalveolar lung. As the respiratory units of most non-mammalian vertebrates are up to 1000-fold larger and up to 100-fold more compliant, surfactant is not required for these functions. 4. In non-mammals, surfactant appears to act as an anti-glue preventing the adhesion of respiratory surfaces that may occur when the lungs collapse (e.g. during diving, swallowing of prey or on expiration). Surfactant also controls lung fluid balance. These functions can be fulfilled by a surfactant with relatively low surface activity and may represent the primitive functions of surface active material in vertebrate lungs.  相似文献   
86.
Efficiency of pulse-therapy with prospidin (500 mg for 5 days in hospital, 500-1000 mg for a month as maintenance) and methotrexate (30 mg a week i.v. in hospital, 7-10 mg a week as maintenance) was investigated in 93 patients with severe RA. The response to prospidin and methotrexate arose quickly (within 10-14 and 4-5 weeks, respectively) and occurred in 73 and 70% of patients, respectively. Withdrawal of the drug was caused by side effects of methotrexate (19.3%) and resistance to prospidin (23.2%).  相似文献   
87.
Formation of delta pH is registered when studying Ca2+ passive transport through lymphocytes' plasma membrane (PM). The pHi values strongly depended on pH0. Changes of pH0 lead to unidirectional changes of pHi and affect Ca2+ concentration in cytoplasm of the intact cells. The presence of Ca(2+)-channels antagonists does not affect this phenomenon. Ca2+/H+ exchange is supposed to exist in PM. It is also of great interest that cytoplasmic Ca2+ and H+ activities are some equal in physiological range. Besides, H(+)-buffering as well as Ca(2+)-buffering systems are present in the cell and have their maximal capacity about 7.2 in the intact cells. The spectrofluorimetric study of internal lymphocytes' H(+)-buffering capacity with titration technique using weak base, acid or other buffer addition has demonstrated maximal value of 9.0-1.1 mM depending on the substance to be added.  相似文献   
88.
The suture insufficiency have occurred in 26 (15%) patients after operative treatment of 179 patients with different diseases of small intestine. The main methods of treatment of this patients are the surgical procedures, intestinal intubation, rational antibioticotherapy, the hemostasis correction for the postoperative peritonitis liquidation.  相似文献   
89.
The literature has been reviewed to evaluate the technique and clinical value of radionuclide measurements of microvascular permeability and oedema formation in the lungs. Methodology, modelling and interpretation vary widely among studies. Nevertheless, most studies agree on the fact that the measurement of permeability via pulmonary radioactivity measurements of intravenously injected radiolabelled proteins versus that in the blood pool, the so-called pulmonary protein transport rate (PTR), can assist the clinician in discriminating between permeability oedema of the lungs associated with the adult respiratory distress syndrome (ARDS) and oedema caused by an increased filtration pressure, for instance in the course of cardiac disease, i.e. pressure-induced pulmonary oedema. Some of the techniques used to measure PTR are also able to detect subclinical forms of lung microvascular injury not yet complicated by permeability oedema. This may occur after cardiopulmonary bypass and major vascular surgery, for instance. By paralleling the clinical severity and course of the ARDS, the PTR method may also serve as a tool to evaluate new therapies for the syndrome. Taken together, the currently available radionuclide methods, which are applicable at the bedside in the intensive care unit, may provide a gold standard for detecting minor and major forms of acute microvascular lung injury, and for evaluating the severity, course and response to treatment.  相似文献   
90.
On an experimental basis in the Institute of Cytology and Genetics Siberian Division, Russian Academy of Sciences, a cage population of river otter (Lutra lutra) was formed. During the introduction period of captivity, as the selection for stress resistance in an anthropogenic environment is shown to be a crucial factor. Through the course of domesticating river otters, directional selection occurs due to the increase in the number of individual otters and to the absence of fear-induced response toward humans. In the initial generation caught in the wild, three types of animals were revealed: cowardly or showing a fear-induced response (80%), aggressive (10%), and quiet (10%). After three generations were reared in captivity, the relationship between these three phenotypes changed in favor of otters with a quiet response toward man; the percentage increased. After three generations, these quiet animals comprised 37%. The percentages of aggressive and cowardly animals accounted for 11 and 52%, respectively.  相似文献   
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