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1.
Abstract : Orally administered anticancer drugs facilitate treatment, but the acidic conditions in the stomach often challenge their availability. PhenolaTi is a TiIV-based nontoxic anticancer drug with marked in-vivo efficacy. We report that nanoformulation protects phenolaTi from decomposition in stomach-like conditions. This is evidenced by similar NMR characteristics and similar in-vitro cytotoxicity toward murine (CT-26) and human (HT-29) colon cancer cells before and after incubation of nanoformulated phenolaTi (phenolaTi-F) at pH 2, unlike results with the unformulated form of the complex. Furthermore, administration of phenolaTi-F in animal drinking water revealed a notable inhibition of tumor growth in Balb/c and immune-deficient (Nude) mice inoculated with CT-26 and HT-29 cells, respectively. In-vivo efficacy was at least similar to that of the corresponding intraperitoneal treatment with phenolaTi-F and the clinically employed oral drug, capecitabine. No body weight loss or clinical signs of toxicity were evident in the phenolaTi-F-treated animals. These findings demonstrate a new convenient mode of cancer treatment through oral administration by safe titanium-based drugs.  相似文献   
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We measured the dissipation resulting from internal friction in hcp solid 4He at temperatures between 0.8 K and 2.5 K. Solid 4He is contained inside an annular metal cell forming a part of a torsional oscillator. An oscillatory motion of the cell walls applies shear stress on the solid 4He. The resulting shear strain within the solid 4He generates dissipation because of the internal friction. The experimental sensitivity was high enough to detect dissipation caused by internal friction associated with elementary excitations of the solid. At temperatures below 1.6 K, internal friction is associated with diffusion of single point defects responsible for the climb of dislocations. At higher temperatures, the main mechanism of internal friction appears to be associated with phonon exchange between parts of the solid moving relative to each other under the applied shear stress. This particular dissipative mechanism was called “quantum phonon friction” [Popov in Phys. Rev. Lett. 83:1632–1635, 1999]. The physical mechanism associated with this type of friction involves an irreversible transfer of momentum from the phonons to the lattice via an Umklapp process. Our data are in a very good agreement with this model.

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The authors investigated the direct and interactive effects of the job demand– control–support (JDC-S) model’s components on subsequent changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides (TRI) separately for male and female employees. In contrast to all 14 past studies on these relationships, the authors used a longitudinal design. Study participants (N = 1,137, 66% men) were all apparently healthy employees who underwent a routine health check at 2 points in time (Time 1 and Time 2) about 22 months apart. In these analyses, the authors controlled for the Time 1 level of each criterion and for other confounders. Most of the direct and moderating effects found did not support the predictions of the JDC-S model; this finding is in agreement with the majority of past cross-sectional studies. The authors did not find any evidence supporting the existence of a reverse causation for either of the components of the JDC-S model. The authors suggest that serum lipids may not be a physiological mechanism mediating the effects of the JDC-S model on atherosclerotic diseases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper presents a new simple, rapid, and accurate method suitable for on-site measurement of volatile fatty acids (VFA) and carbonate alkalinity in anaerobic reactors. This titrimetric method involves eight pH observations, and typically, the full procedure takes approximately 15 min. An important feature of the method is a built-in quality control mechanism allowing the user a rapid means of assessing the reliability of the experimental procedure. To evaluate the accuracy of the method, both laboratory-made waters and industrial UASB effluent were tested. High accuracy for both VFA and carbonate alkalinity measurements (error within 2% and 1%, respectively) plus good repetition (average standard deviation of 6.7% and 1.45%, respectively) was obtained. The method takes into account the effects of the phosphate, ammonium, and sulfide weak acid subsystems. Appraisal of the effect of an input error in these subsystems revealed that VFA measurement is fairly insensitive to phosphate and ammonium concentrations. It is, however, sensitive to H2S loss during titration where the sulfide concentration is higher than approximately 10 mg/Las S. With regard to the carbonate alkalinity measurement, error in concentration of either phosphate or sulfide or H2S loss might result in a significant error. Short guidelines for correct execution of the method are given in an appendix.  相似文献   
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Oral pulse therapy with vitamin D is effective in suppressing parathyroid hormone (PTH) secretion in continuous ambulatory peritoneal dialysis patients with secondary hyperparathyroidism (2'hpt). However, this treatment often leads to hypercalcemia. The goals of the study were: (1) to examine whether the incidence of hypercalcemia decreases when dialysate calcium is reduced from 1.25 to 1.0 mmol/L; (2) to determine the relative role of the factors involved in the pathogenesis of hypercalcemia; and (3) to study the efficacy of a low oral pulse dose of alfacalcidol in preventing the recurrence of 2'hpt. Fourteen continuous ambulatory peritoneal dialysis patients with 2'hpt were treated with pulse oral alfacalcidol and calcium carbonate and dialyzed with a 1.0-mmol (n = 7) or a 1.25-mmol (n = 7) dialysate calcium. The response rate (87%) and the incidence (71%) and severity of hypercalcemia were similar in both groups. In the early response stage, PTH decreased by 70% in both groups, and serum ionized calcium (iCa) increased from 1.18 +/- 0.02 to 1.27 +/- 0.04 mmol/L (P < 0.005) in the 1.0 group and from 1.19 +/- 0.02 to 1.29 +/- 0.02 mmol/L in the 1.25 group (P < 0.005). Nine of the 12 responders had a further decrease in serum PTH, which was associated with an additional increase in iCa from 1.28 +/- 0.02 to 1.47 +/- 0.04 (P < 0.005). Multivariate analysis showed that the early increase in iCa was positively correlated with alfacalcidol dosage (r = 0.69). In contrast, the late increase in iCa was mostly accounted for by the decrease in serum PTH (r = -0.93). This occurred while calcium carbonate, alfacalcidol dosage, and serum 1,25 hydroxy D3 remained unchanged compared with the early response stage. Finally, an alfacalcidol dose of 1 microg twice weekly was unable to maintain serum PTH at an adequate level in the long term. These data show that a reduction in dialysate calcium from 1.25 to 1.0 mmol does not reduce the occurrence of hypercalcemia and suggest that lowering serum PTH reduces the ability of the bone to handle a calcium load within a few weeks, thus causing hypercalcemia.  相似文献   
6.
Series of loading tests were carried out on epoxy resin specimens, at varying constant strain rates, under tension, compression, and flexure. The stress–strain relationship revealed a distinct yielding stage followed shortly by a post-yielding region of decreasing load. In all cases, results indicate linearity between yield stress and log strain rate, in accordance with Eyring's theory of viscous flow. For specimens unloaded close to the yield point, photoelastic observations revealed a residual pattern parallel to the theoretical principal shear stresses. These results, supported by additional data from other works, indicate a viscoplastic deviatoric stress-biased diffusional mechanism as the dominant factor in the yielding of an amorphous crosslinked epoxy system.  相似文献   
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Inspired by attachment theory, the authors tested a series of theoretically derived predictions about connections between attachment working models (attachment to one's parents assessed by the Adult Attachment Interview; M. Main & R. Goldwyn, 1994) and the effectiveness of specific types of caregiving spontaneously displayed by dating partners during a stressful conflict-resolution discussion. Each partner first completed the Adult Attachment Interview. One week later, each couple was videotaped while they tried to resolve a current problem in their relationship. Trained observers then rated each interaction for the degree to which (a) emotional, instrumental, and physical caregiving behaviors were displayed; (b) care recipients appeared calmed by their partners' caregiving attempts; and (c) each partner appeared distressed during the discussion. Individuals who had more secure representations of their parents were rated as being more calmed if/when their partners provided greater emotional care, especially if they were rated as more distressed. Conversely, individuals who had more insecure (dismissive) representations of their parents reacted more favorably to instrumental caregiving behaviors from their partners, especially if they were more distressed. The broader theoretical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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