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31.
Low-dose, chronic administration of the synthetic glucocorticoid, dexamethasone, to male CD-I rats in the drinking water or by osmotic minipumps implanted subcutaneously after supralethal irradiation of the kidneys (20 Gy) was studied. The effectiveness of treatment with dexamethasone in the drinking water at concentrations of 23 micrograms/l to 188 micrograms/l and treatment times varying from 33 to 166 days was evaluated. At monthly intervals kidney function was assayed by measuring the clearance of 51Cr-ethylenediaminetetraacetic acid. All dexamethasone treatment regimens increased survival times significantly and delayed the development of kidney dysfunction. The most effective combination of concentration of dexamethasone in drinking water and treatment interval after irradiation with respect to survival was 94 micrograms/l and 88 days. However, a slightly longer survival and a better functional result was obtained if an equivalent amount of dexamethasone was administered by minipumps. Shielding the adrenal glands during kidney irradiation did not prolong survival. This shows that the beneficial effect of dexamethasone is not due to compensation for reduced adrenal glucocorticoid production resulting from concomitant exposures of these glands during kidney irradiation.  相似文献   
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Microfluidic technologies are highly adept at generating controllable compositional gradients in fluids, a feature that has accelerated the understanding of the importance of chemical gradients in biological processes. That said, the development of versatile methods to generate controllable compositional gradients in the solid‐state has been far more elusive. The ability to produce such gradients would provide access to extensive compositional libraries, thus enabling the high‐throughput exploration of the parametric landscape of functional solids and devices in a resource‐, time‐, and cost‐efficient manner. Herein, the synergic integration of microfluidic technologies is reported with blade coating to enable the controlled formation of compositional lateral gradients in solution. Subsequently, the transformation of liquid‐based compositional gradients into solid‐state thin films using this method is demonstrated. To demonstrate efficacy of the approach, microfluidic‐assisted blade coating is used to optimize blending ratios in organic solar cells. Importantly, this novel technology can be easily extended to other solution processable systems that require the formation of solid‐state compositional lateral gradients.  相似文献   
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Organic solar cells based on ternary active layers can lead to higher power conversion efficiencies than corresponding binaries, and improved stability. The parameter space for optimization of multicomponent systems is considerably more complex than that of binaries, due to both, a larger number of parameters (e.g., two relative compositions rather than one) and intricate morphology–property correlations. Most experimental reports to date reasonably limit themselves to a relatively narrow subset of compositions (e.g., the 1:1 donor/s:acceptor/s trajectory). This work advances a methodology that allows exploration of a large fraction of the ternary phase space employing only a few (<10) samples. Each sample is produced by a designed sequential deposition of the constituent inks, and results in compositions gradients with ≈5000 points/sample that cover about 15%–25% of the phase space. These effective ternary libraries are then colocally imaged by a combination of photovoltaic techniques (laser and white light photocurrent maps) and spectroscopic techniques (Raman, photoluminescence, absorption). The generality of the methodology is demonstrated by investigating three ternary systems, namely PBDB‐T:ITIC:PC70BM, PTB7‐Th:ITIC:PC70BM, and P3HT:O‐IDFBR:O‐IDTBR. Complex performance‐structure landscapes through the ternary diagram as well as the emergence of several performance maxima are discovered.  相似文献   
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Biological pathways play an important role in the occurrence, development and recovery of complex diseases, such as cancers, which are multifactorial complex diseases that are generally caused by mutation of multiple genes or dysregulation of pathways. We propose a path-specific effect statistic (PSE) to detect the differential specific paths under two conditions (e.g. case VS. control groups, exposure Vs. nonexposure groups). In observational studies, the path-specific effect can be obtained by separately calculating the average causal effect of each directed edge through adjusting for the parent nodes of nodes in the specific path and multiplying them under each condition. Theoretical proofs and a series of simulations are conducted to validate the path-specific effect statistic. Applications are also performed to evaluate its practical performances. A series of simulation studies show that the Type I error rates of PSE with Permutation tests are more stable at the nominal level 0.05 and can accurately detect the differential specific paths when comparing with other methods. Specifically, the power reveals an increasing trends with the enlargement of path-specific effects and its effect differences under two conditions. Besides, the power of PSE is robust to the variation of parent or child node of the nodes on specific paths. Application to real data of Glioblastoma Multiforme (GBM), we successfully identified 14 positive specific pathways in mTOR pathway contributing to survival time of patients with GBM. All codes for automatic searching specific paths linking two continuous variables and adjusting set as well as PSE statistic can be found in supplementary materials.  The proposed PSE statistic can accurately detect the differential specific pathways contributing to complex disease and thus potentially provides new insights and ways to unlock the black box of disease mechanisms.  相似文献   
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Biogeochemistry - The initial online publication contained typesetting mistakes in the author information. The original article has been corrected.  相似文献   
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Food Biophysics - Absorption of bioactive peptides in the intestinal epithelium take place in the apical or the basolateral tight junctions of the cells. Depending on the peptide size and...  相似文献   
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Applying latent class and regression techniques to data from the NICHD Study of Early Child Care and Youth Development (n = 997), this study explored the potential academic advantages of time spent in out-of-school activities. Of particular interest was how these potential advantages played out in relation to the timing and duration of activity participation and the family contexts in which it occurred. Participation closer to the start of high school—including consistent participants and latecomers—was associated with higher grades at the transition into high school, especially for youth from low-income families. Sensitivity analyses indicated that this link between school-age activity participation and adolescent academic progress was unlikely to be solely a function of selection. It also tended to be more pronounced among youth from lower-income families, although without varying by other aspects of family status or process.  相似文献   
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