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101.
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   
102.
The protection patterns of 5S rRNA in solution, within the ribosomal 50S subunit, 70S ribosomes, and functional complexes, were assessed with the phosphorothioate method. About 20% of the analyzed positions (G9-G107) showed strong assembly defects: A phosphorothioate at one of these positions significantly impaired the incorporation of 5S rRNA into 50S particles. The reverse has also been observed: A phosphorothioate is preferred over a phosphate residue in the assembly process at a few positions. The results further demonstrate that 5S rRNA undergoes conformational changes during the assembly in the central protuberance of the 50S subunit and upon association with the small ribosomal subunit forming a 70S ribosome. In striking contrast, when the 70S ribosomes are once formed, the contact pattern of the 5S rRNA is the same in various functional states such as initiation-like complexes and pre- and posttranslocational states.  相似文献   
103.
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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The experimental technique is presented which allows the investigation of water at the adsorbent-biopolymer interface by record of temperature dependencies of 1H NMR signals during the heating of previously frozen water suspensions. It was found that the adsorption of protein conconovalin A resulted in twofold decrease of strong bound water amount and in 70% increase of loosely bound one. The mean-value of Gibbs energy decreased twice for strong bound water and increased twice for loosely bound one. The external layer of hydrate shell of silica particles with adsorbed conconovalin A was organized by protein molecules. This conclusion is based on the observed total increase of loosely bound water amount, as a result, of protein adsorption, although its amount with respect to a protein molecule decreased.  相似文献   
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The authors submit results of treatment of patients having suffered from postherpetic pain syndrome (herpetic ganglionitis of the cervical, thoracic, lumbosacral localization, postherpetic intercostal neuralgia, ganglionitis of the trigeminal nerve). In viral diseases, amizone has marked analgetic, antiinflammatory, and immunomodulating effects. The drug is well tolerated by patients, is not associated with side effects under prescribed doses (0.25-0.75 as one dose on a three- or four-times daily schedule during the course of treatment lasting three or four weeks). The drug preparation in question is less effective in the treatment of chronic recurring post-therapeutic intercostal neuralgias, radiculalgia.  相似文献   
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1. The pharmacological properties of four synthetic analogues of the wasp neurotoxin, Vespulakinin 1, were studied using a cascade of mammalian smooth muscle preparations and the synaptic transmission from the cockroach cercal nerves to a giant interneuron. 2. All analogues have an extremely slow bradykinin-like effect on the smooth muscles. The carbohydrate-free and the two mono-glycosylated analogues are about equally active with bradykinin. 3. The double glycosylated derivative is about 5 times more potent than bradykinin. 4. All analogues have two different effects on synaptic transmission in the insect CNS--at first a direct and reversible block of excitatory nicotinic transmission with a concurrent activation of the inhibitory GABA-ergic system and, secondly, a delayed irreversible block of the transmission, comparable to the block described earlier for bradykinin and Thr6-bradykinin. 5. For the synaptic transmission in the insect CNS the double glycosylated kinin is about 5 times more potent than bradykinin.  相似文献   
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