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991.
Reviewed R. W. Miskimins, R. DeCook, L. T. Wilson, and R. F. Maley's (see 41:11) Suicide Prevention Scale (SPS), a 23-item checklist based on demography and personality of institutionalized psychiatric patients who committed suicide. An experimental group of 15 suicide cases and 30 nonsuicidal institutionalized controls were scored on the SPS. For precision and brevity an item analysis culled out the least discriminative items. 16 items composed the Revised Suicide Prevention Scale (RSPS). "All 6 study groups, from the original and present research were scored on the RSPS." Results supported the validity of the RSPS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
993.
Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.  相似文献   
994.
995.
In human peripheral blood polymorphonuclear leukocytes and lymphocytes, GSH-oxidizing agents promote the movement of surface-bound concanavalin A (Con A) into caps and inhibit the assembly of microtubules (MT) that is normally induced by Con A binding. Con A capping and inhibition of MT assembly occur when GSH levels in cell suspensions are decreased by 30-70%, and return to GSH to control levels is accompanied by the appearance of cytoplasmic MT and by inhibition of the capping response with Con A. Oxidation of GSH markedly stimulates the hexose monophosphate shunt, and regeneration of GSH occurs rapidly. The data indicate that MT cannot be assembled or maintained in the face of decreased GSH levels. Thus, GSH homeostasis becomes critical during physiological events such as phagocytosis which simultaneously induce the assembly of MT and the production of agents like H2O2 that can oxidize GSH.  相似文献   
996.
An experimental group (N = 19) was trained to receive Morse code with signals that were weighted with respect to frequency of presentation in rough proportion to their order of difficulty for beginners. A control group (N = 19), matched on a code aptitude test performance, was trained with each signal presented an equal number of times. On the test runs, no significant differences were observed in the progress of the two groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
In designing an implantable sensor for perfusion monitoring of transplant organs the ability of the sensor to gather perfusion information with limited power consumption and in near real time is paramount. The following work was performed to provide a processing method that is able to predict perfusion and oxygenation change within the blood flowing through a transplanted organ. For this application, an autocorrelation-based algorithm was used to reduce the acquisition time required for fast Fourier transform (FFT) analysis while retaining the accuracy inherent to FFT analysis. In order to provide data proving that the developed method is able to predict perfusion as accurately as FFT two experiments were developed isolating both periodic and quasi-periodic cardiac frequencies. It was shown that the autocorrelation-based method was able to perform comparably with FFT (limited to a sampling frequency of 300 Hz) and maintain accuracy down to acquisition times as low as 4 s in length.  相似文献   
998.
999.
Deer antler is of interest to material scientists because it represents bone which can withstand applied stresses of over 300 MPa. In this work we demonstrate the presence of nanopores in this material by nuclear magnetic resonance (NMR) spectroscopy, and gas adsorption and mercury intrusion experiments. It is also shown that organic material in the antler influences observed pore sizes. Different modal groups of pores were observed when organic lipid material was removed from the sample and the sample saturated with water. The dominant organic phase associated with the small pores is protein.  相似文献   
1000.
DNA aptamer-based bioanalysis of IgE by fluorescence anisotropy   总被引:3,自引:0,他引:3  
A rapid, homogeneous aptamer-based bioanalysis is reported for the sensitive detection of immunoglobulin E (IgE) using fluorescence polarization (FP). 5'-End-labeled D17.4 DNA aptamer was used for IgE detection based on the anisotropy differences of the labeled ligand. Two different fluorophores, fluorescein and Texas Red, were used to analyze IgE in the low-nanomolar range with high specificity. Measurable anisotropy changes were observed with a short equilibration time. Analysis of the binding data reveals a possible cooperative binding process in solution. The nature of the fluorophore clearly influences the sensitivity of the analysis more than the tether length used for the dye conjugation. The local fluorophore motion is seen to influence the sensitivity of the FP probe significantly. Texas Red is seen to be relatively more sensitive for this approach and has apparently favorable dye-DNA interactions, and a limit of detection of 350 pM was obtained. Significant temperature dependence of the FP responses has been observed in this work. Ionic composition of the binding buffer also influences the assay sensitivity. The results confirm the promise and potential of similar homogeneous assays for aptamer-based bioanalysis.  相似文献   
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