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231.
Doklady Biochemistry and Biophysics - To search for compounds with antiprotozoal activity, effects of snake venoms on the ciliates Tetrahymena pyriformis was studied. T. pyriformis from subkingdom...  相似文献   
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Erythrocyte populations from newborn and mature mice were characterized according to: size; ultrastructural features; water content; concentration of intraerythrocyte elements including Na, Cl, K, P, S, Mg, and Fe; and the spinlattice (T1) and spin-spin relaxation times of water protons as measured by nuclear magnetic resonance (NMR) spectroscopy. A significant increase in the T2 time from 142 +/- 3 msec to 184 +/- 3 msec occurred during erythrocyte maturation. This change in T2 time was correlated with a change from a polyribosome-rich hemoglobin-poor cell type to a polyribosome-absent hemoglobin-rich cell type. The change in T2 time could also be correlated to a significantly higher K and P concentration in the mature erythrocytes. The change in T2 time was not correlated to a change in cellular water content or to the concentration of any of the other elements measured by electron probe X-ray microanalysis. If the NMR relaxation times of water molecules truly reflect their average motional freedom, then the findings suggest that greater water ordering interaction occurs in the ribosome containing immature erythrocyte.  相似文献   
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Background  

Gastrointestinal (GI) endoscopy has been popularly applied for the diagnosis of diseases of the alimentary canal including Crohn's Disease, Celiac disease and other malabsorption disorders, benign and malignant tumors of the small intestine, vascular disorders and medication related small bowel injury. The wireless capsule endoscope has been successfully utilized to diagnose diseases of the small intestine and alleviate the discomfort and pain of patients. However, the resolution of demosaicked image is still low, and some interesting spots may be unintentionally omitted. Especially, the images will be severely distorted when physicians zoom images in for detailed diagnosis. Increasing resolution may cause significant power consumption in RF transmitter; hence, image compression is necessary for saving the power dissipation of RF transmitter. To overcome this drawback, we have been developing a new capsule endoscope, called GICam.  相似文献   
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[Nle7]-endothelin was synthesized and studied by 1H NMR and distance geometry calculations. The NMR study was performed first in DMSO-d6 and then in 50% acetonitrile/water since this peptide aggregates in pure water. In both cases, all spin systems were identified and assigned with the aid of two-dimensional spectroscopy (2D): COSY (for scalar couplings) and NOESY (for dipolar couplings). On the basis of the acetonitrile/water NMR parameters, and using the DISGEO program, a three-dimensional structure of [Nle7]-endothelin is proposed and discussed.  相似文献   
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Especially coated adrenaline tablets (A) or placebo tablets (P) which release linearly the hormone were implanted in male Wistar rats. Six hours later animals were sacrificed and kinetic parameters of T3-125I binding to nuclear receptor, intracellular distribution of endogenous T3 and activities of alfa-GPD and ME were investigated. The association constant values (Ka) of nuclear receptor were increased after pretreatment with 7.5, 15 and 45 mg A tablets and were 1.07, 1.35 and 1.48 X 10(9) M-1 vs 0.85 X 10(8) M-1 value seen after P. The maximal binding capacity (MBC) values decreased after pretreatment with the same doses of A and were 0.044, 0.036 and 0.025 pmol T3/100 micrograms DNA vs. 0.065 pmol T3/100 micrograms DNA in P pretreated. Adrenaline pretreatment significantly increased the amount of endogenous T3 present in liver nuclei while the amount of T3 present in cytosol decreased. Activity of mitochondrial alfa-GPD was increased after 15 and 45 mg of A. Significant rise of activity of cytosol ME was seen only after pretreatment with 45 mg of A.  相似文献   
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