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11.
A study was made into the functional status of hypophysis, adrenal cortex, ovaries, and thyroid gland in patients with kraurosis and leukoplakia vulvae. The above patients demonstrated profound disturbances in the system hypophysis-ovaries, that attest to the need for applying corrective therapies to treat the disturbed hormonal homeostasis.  相似文献   
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OBJECTIVE: The present study was undertaken to evaluate the efficacy and safety of amlodipine for hypertension treatment in comparison with nifedipine retard. METHODS: We examined 31 patients with arterial blood pressure approximately 155-165 mmHg/100-105 mm Hg at the beginning of the trial. It was a randomized double-blind, parallel-group trial including two groups of patients. Patients of the first group were given active amlodipine and nifedipine retard placebo during 6 weeks, while the second group was given active nifedipine retard and amlodipine placebo. Statistical analysis was made using the paired Student's t-test, chi-square test and ANOVA test. RESULTS: At end point we observed significant decrease in arterial blood pressure after treatment of both drugs. The treatment with nifedipine retard increased the mean heart rate of patients. Amlodipine therapy in comparison to nifedipine retard did not change the heart rate in treated patients. Safety parameters: SGOT, SGTP, creatinine and others were in laboratory norms ranges. CONCLUSION: Amlodipine proved to be an effective, more safe and better-tolerated therapeutical alternative for hypertension management than nifedipine retard.  相似文献   
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Heterojunctions in the Sn/Si and Pb/Si systems are observed for larger temperature ranges than have previously been reported. Reflection high energy electron diffraction and depth selective Mössbauer spectroscopy investigations are carried out together with conventional electrical measurements for the Sn/Si system in an attempt to explain the observed inverse layer at the Sn-Si boundary. The contact of tin and lead with silicon of different resistivities is discussed. A new crystalline state of tin is observed when tin is evaporated onto (111)Si. It is diamond cubic with a = 5.60±0.06 A? and the isometric shift δ has a very high positive value (+4.42±0.34 mms?1>) relative to SnO2. For longer heating times there is a decrease of δ at 400°C to +2.75±0.34 mm s-1 relative to SnO2. The reasons for the difference in the electrical behaviour below and above 400 °C of the Sn/Si heterojunctions are discussed.  相似文献   
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Quantitative measurements of protein interaction strengths, crucial for describing signaling networks and predicting cellular responses to environmental stimuli, are typically performed in dilute buffer solutions. However, protein-protein interactions in cells occur within the context of a crowded system, which is characterized by a high macromolecular concentration. In this paper, we explore the utility of cell-derived vesicles as a model crowded environment for quantitative FRET measurements of protein-protein interactions. We show that the FRET efficiency, and the donor and acceptor concentrations, can be calculated in each vesicle. We also introduce the "quantitative imaging Foster resonance energy transfer" method as a tool that can yield protein interaction strengths within these vesicles.  相似文献   
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The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty‐six slabs of bovine incisors enamel (5 × 3 × 2.5 mm3) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH = 2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (λ = 10.6 µm; 0.5 W) and nonirradiate. After a 2‐day lead‐in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross‐over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three‐way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P = 0.419). Erosive challenge significantly increased enamel wear (P = 0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2‐laser irradiated and non‐irradiated (P = 0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid. Microsc. Res. Tech. 77:586–593, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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ABSTRACT

The solvent extraction of americium from nitric acid by several modified bifunctional extractants in CCl4has been investigated. For all the compounds examined, addition of a modifier such as tributylphosphate (TBP) enhances distribution ratios at high aqueous acidities. The effect of the modifier at lower acidities varies depending on the basicity of the bifunctional extractant. While the most basic extractants show significantly reduced distribution ratios from lower acid solutions upon TBP addition, for the less basic compounds only slight reductions or, in some cases, even moderate increases in extraction are observed. Studies of the effect of modifier basicity on extraction behavior have also been carried out. The changes in distribution ratios with modifiers fall within the range of variations observed for diluent effects with extractants of this type. Increases in high acid distribution ratios upon TBP addition to an extractant as simple as trioctylphosphine oxide indicate that this modification of extraction behavior may be of general use for a wide range of neutral extractants  相似文献   
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