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571.
572.
The method of natural periodization of processes based on objective quantitative account of the dynamics of changing of certain parameters is described. The natural periodization has been established by analysis of the data dynamic series, the distribution of observation terms being made with regard for the a priori taken rate of changes of the parameters under study. The possibility to compare different parameters has been achieved by using centrated approximated data. The discovering of natural periods can be performed by analysis of the group of centrated data. The variation of the variation coefficient of centrated ordinates in each temporal point can be calculated for objectivization of the evaluation. The investigation of developmental changes of the thyroid of A/H mice with employment of methods of morphometry and quantitative histochemistry is taken as an example.  相似文献   
573.
574.
The human receptor for the potent eosinophilopoietic cytokine interleukin-5 (IL-5) consists of two components: a 60-kDa ligand-binding alpha chain (IL-5 alpha R) and a 130-kDa beta chain (IL-5 beta R). Three ectodomain constructs of the alpha chain (alpha RED) bearing C-terminal epitope tags were engineered and expressed in baculovirus-infected Sf9 cells. Each recombinant alpha chain was secreted into the medium, maximum expression occurring 72 h post-infection. The various soluble alpha chains were shown by affinity cross-link labeling and competition with unlabeled IL-5 to bind recombinant human (rh) 125I-IL-5 specifically with an ED50 of 2-5 nM. The epitope tag provided a simple purification of the receptor from conditioned medium using immunoaffinity chromatography. The purified material had an apparent molecular mass of 43 kDa and was heterogeneously glycosylated. Sedimentation analysis revealed a 1:1 association of the purified epitope-tagged soluble receptor with its ligand, resulting in the formation of a 70-74-kDa complex. Circular dichroism analysis revealed that the soluble alpha chain existed with a significantly ordered structure consisting of 42% beta-sheet and 6% alpha-helix. Such analyses combined with fluorescence spectrometry suggested that ligand-receptor complex formation in solution resulted in minimal conformational changes, consistent with the suggestion that the membrane-associated form of the alpha chain itself has minimal signal transduction capability. Surface plasmon resonance studies of the interaction of the purified alpha RED with immobilized rhIL-5 revealed a specific, competable interaction with a dissociation constant of 9 nM. Preincubation of an IL-5-dependent cell line with the epitope-tagged alpha RED also dose-dependently neutralized rhIL-5-induced proliferation. These data demonstrate that biologically active epitope-tagged recombinant soluble IL-5 receptors are facile to produce in large quantities and may have therapeutic utility in the modulation of IL-5-dependent eosinophilia in man.  相似文献   
575.
A case of a tumor of the upper lid involving the bons in a 6 1/2 year old body is reported. Histology revealed a solitary eosinophilic granuloma. The classification of this systemic disease which almost always shows an orbital manifestation is discussed.  相似文献   
576.
Changes of membrane potential (MP), amplitude of action potential (AAP) and continuence of AP (CAP) of identified neurons of leech Haemopis sanguisuga have been investigated at high intracellular Na+ concentration. It has been shown that a moderate increase of intracellular Na+ concentration leads to hyperpolarization of the membrane to 15 mV and a certain increase of AAP and CAP. A further increase of [Na+]in leads to a sharp decrease of AAP and small decrease of CAP. Possible mechanisms of the phenomena described are discussed.  相似文献   
577.
OBJECTIVE: To describe the techniques and applications of exercise echocardiography. DESIGN: We review pertinent experimental and clinical studies from the literature and present our experience with the first 2,000 patients who underwent exercise echocardiography in our laboratory. MATERIAL AND METHODS: The indications for and contraindications to exercise echocardiography and the advantages, limitations, and accuracy of this procedure in comparison with other techniques for detecting coronary artery disease are discussed. RESULTS: Exercise echocardiography is increasingly used for the noninvasive evaluation of coronary artery disease because, in addition to its diagnostic capabilities, it offers attractive features such as portability, versatility, rapid availability of results, and relatively low cost. For accurate interpretation of the results, the workload achieved and the time between completion of exercise and image acquisition must be considered. The major limitation of exercise echocardiography is the high degree of operator dependence. For accurate interpretation of regional wall motion abnormalities and recognition of ischemic changes, specific training and extensive experience are necessary. CONCLUSION: Although exercise echocardiography has only relatively recently become a widely used technique, it has proved to have considerable accuracy in the diagnosis of coronary artery disease (mean sensitivity, 84%; mean specificity, 87%). In high-volume laboratories, feasibility studies have shown success rates between 90 and 99%; thus far, reproducibility has been satisfactory. Other applications of exercise echocardiography being studied are follow-up monitoring after revascularization, determination of prognosis, and assessment of valvular heart disease.  相似文献   
578.
After prednisone (two 5 mg tablets) was given to each of six normal volunteers with water or with a liquid meal, standard pharmacokinetic parameters of prednisolone metabolism were similar, except that peak serum prednisolone concentrations occurred later after the meal. We conclude that prednisone can be given with a meal without significantly affecting the metabolism of prednisone or prednisolone.  相似文献   
579.
The sensitivity to gamma-rays of a hyperkinetic mutant (HK1), characterized by high metabolic activity, has been studied and compared with gamma-ray sensitivity of the wild-type Oregon-K. Radiation damage, as measured by the frequency of induced dominant lethals (DL) and sex-linked recessive lethals (SLRL), was more in HK1 as compared with Or-K. The maximal sensitivity differences for these parameters were observed in the first brood. Translocations, on the contrary, were in general fewer in the HK1 compared with Or-K. These results have been interpreted in terms of reduced repair of mutational lesions in the energy-stressed cells of KH1.  相似文献   
580.
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