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Abstract— The fluorescence lifetime and degree of fluorescence polarization of hematoporphyrin derivative (HpD) have been investigated using different solutions: organic and micellar solutions. Ham's F12 medium, and KK-47 cell suspension. The lifetime and polarization degree in organic and micellar solutions did not change with increasing incubation time, but the polarization degree in the cell suspensions temporarily increased at the initial incubation time and then decreased 4 h after incubation. The lifetime in the cell suspensions exhibited a bi-phasic exponential decay. The results obtained suggested that mainly dimeric HpD may bind weakly to the cell membrane, and then slowly be distributed throughout the cytoplasm. The polarity and viscosity of the intracellular loci containing HpD were evaluated from the fluorescence polarizations of HpD in MeOH-H2O mixtures and ethylene glycol(EG)-MeOH mixtures. The dielectric constant and viscosity of the loci containing HpD were 35 and 11 cp, respectively. Accordingly, the intracellular location of HpD were considered relatively hydrophilic loci of the cells.  相似文献   
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I: METHODOLOGY     
Since standard molecular simulations use different energy expressions for charge and gradient calculations, there are severe problems such as incompleteness in the optimization and simulation of the system with electrostatic (ES) interaction. Here, a new concept is proposed to solve this problem. The consistent charge equilibration (CQEq) equation has been derived which uses the same energy expression for both charge and gradient calculations. The ES energy is given by the atomic partial charge shielded with a nuclear charge described by a normalized S type Slater function located at each atomic site. The partial charge is determined by the variational principal for the ES energy with a constraint that the total sum of the partial charges is constant. Also the first derivative has been determined for the ES energy to the internal coordinates from the same ES energy expression. Although the CQEq is a little heavier than the original QEq for the charge calculation, the CQEq completely satisfies the variational principle for the ES energy of a set of partial charge, and satisfies the consistency requirement in the optimization of the system with ES interaction. A new code has been created and applied to test cases.  相似文献   
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Objective: Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse event experienced by cancer patients. In general, CIPN is evaluated subjectively based on patient self-assessment or clinician-reported scales; evidence supporting the utility and validity of quantitative sensory tests (QST) is lacking in this patient population. The aim of this study was to objectively assess CIPN of lower extremities by QSTs, and to evaluate the concordance between QSTs and subjective assessments. Methods: In this prospective cohort study, outpatients with cancer receiving chemotherapy were recruited at a single university hospital. We assessed CIPN at the lower extremities at baseline and three months after baseline. The QSTs were performed by applying a monofilament and a tuning fork to determine touch and vibration thresholds, respectively, at the affected site. Subjective assessments were performed based on the visual analog scale (VAS) and the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) toxicity grade. Kappa coefficients were calculated to evaluate the concordance between QSTs and subjective assessments. Results: After exclusion and drop-outs during follow-up, nineteen patients were included in the analysis. The prevalence of patients with abnormal sensation was 37% based on QSTs, 32% based on the VAS, and 14% based on CTCAE grading, respectively. Kappa coefficients were 0.32 between QSTs and VAS, and 0.28 between QSTs and CTCAE. Conclusions: The concordance rates between quantitative and subjective assessments were low. CIPN should be assessed using both quantitative and subjective assessments.  相似文献   
4.
Abstract— The ciliated protozoan Paramecium bursaria is photosensitive. Retinal, which is the chromophore of the visual pigments of many multicellular animals, was extracted from P. bursaria and identified by HPLC. The procedure of identification was based on the change in polarity achieved by reducing retinal with sodium borohydrate to form retinol. This method is useful for the detection of small amounts of retinal in cells containing large amounts of other substances with similar polarity. The presence of retinal in P. bursaria suggests that this ciliate may contain a photoreceptor pigment with retinal as the chromophore.  相似文献   
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A simple method is presented for calculating Talmi coefficients of Laguerre Gaussians by using those of Hermite Gaussians as intermediates. This method does not require the angular momentum algebra of 3j and 9j symbols needed in the usual methods.  相似文献   
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