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91.
A series of [[(heterocyclyl)ethoxy]benzyl]-2,4-thiazolidinediones have been synthesized by the condensation of corresponding aldehyde 1 and 2,4-thiazolidinedione followed by hydrogenation. Both unsaturated thiazolidinedione 2 and its saturated counterpart 3 have shown antihyperglycemic activity. Many of these compounds have shown superior euglycemic and hypolipidemic activity compared to troglitazone (CS 045). The indole analogue DRF-2189 (3g) was found to be a very potent insulin sensitizer, comparable to BRL-49653 in genetically obese C57BL/6J-ob/ob and 57BL/KsJ-db/db mice. Pharmacokinetic and tissue distribution studies conducted on BRL-49653 and DRF-2189 (3g) indicate that these drugs are well-distributed in target tissues. On the basis of euglycemic activity as well as enhanced selectivity against reduction of triglycerides in plasma, DRF-2189 (3g) has been selected for further evaluation.  相似文献   
92.
Distant metastasis from head and neck cancer is an extremely rare phenomenon. Squamous carcinomas of the buccal mucosa is not known to spread to distant organs. We report a case of buccal mucosal carcinoma with biopsy proven metastasis to bone and bone marrow.  相似文献   
93.
The study of macromolecular structure of coal has been subjected to intense research. Neyveli lignite was depolymerized using phenol and phosphotungstic acid and the resultant product was subsequently alkylated. The t-butylated depolymerized lignite exhibited enhanced extractability in organic solvents. The t-butylated depolymerized lignite was fractionated into different components using column chromatography (CC). Three major compounds were isolated and were characterized by FTIR, 1H NMR and Mass spectral techniques.  相似文献   
94.
The paper presents a computational method for predicting the initial geometry of a finitely deforming anisotropic elastic body from a given deformed state. The method is imperative for a class of problem in stress analysis, particularly in biomechanical applications. While the basic idea has been established elsewhere Comput. Methods Appl. Mech. Eng. 1996; 136 :47–57; Int. J. Numer. Meth. Engng 1998; 43 : 821–838), the implementation in general anisotropic solids is not a trivial exercise, but comes after a systematic development of Eulerian representations of constitutive equations. In this paper, we discuss the general representation in the context of fibrous hyperelastic solids, and provide explicit stress functions for some commonly used soft tissue models including the Fung model and the Holzapfel model. A three‐field mixed formulation is introduced to enforce quasi‐incompressibility constraints. The practical utility of this method is demonstrated using an example of aneurysm stress analysis. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
95.
We explore parallel fiber optics and single-chip CMOS interface solutions to support broadband multimedia applications in a small workgroup environment. Initial implementation of a network interface card used in our testbed of Intel Pentium-based PCs is described. The feasibility of a CMOS bridge to parallel optics is demonstrated using on adapter chip implemented in 0.5 μm CMOS technology for a point-to-point configuration and providing a measured peak bandwidth of 4.8 Gb/s on independent transmit and receive directions. In addition, we describe the design of a gigabyte-per-second parallel fiber optic network interface for a slotted ring network currently being developed. We present a medium access control to be implemented on a single CMOS chip The proposed network is a potentially cost-effective solution for small workgroup clusters  相似文献   
96.
97.
A new method called modified adaptive line enhancement (MALE) to obtain evoked potentials with minimum stimulus repetitions is described. The theory of MALE is developed and the assumptions made are tested and shown to be adequate in the case of brain-stem auditory evoked potential. The signal distortion are characterized and methods to alleviate the problem are developed. Using the weighted exact least squares lattice algorithm, the MALE method is implemented and applied to real data. It is shown that brainstem auditory evoked potential can be obtained with less than 40 repetitions using MALE method compared to 2000 required if conventional ensemble averaging method is used.  相似文献   
98.
Abstract: Iron and zinc deficiencies are the most prevalent nutrient deficiencies worldwide. They often coexist as the dietary factors, especially phytate, which impairs iron absorption also affects zinc absorption. Therefore, suitable strategies are required to control multiple micronutrient deficiencies in populations that subsist on high‐phytate foods such as the whole wheat flour based Indian bread (chapatti). The objective of the study, therefore, was to test the bioavailability of iron and zinc in 2 multiple micronutrient beverage premixes in the absence and presence of chapatti. The premix‐1 contained iron, zinc, and vitamin A while premix‐2 contained all micronutrients in premix‐1, plus folic acid and ascorbic acid. Ferritin induction and 65Zn uptake were assessed using coupled in vitro digestion/Caco‐2 cell line model as the surrogate markers of iron and zinc bioavailability, respectively. The results show that iron bioavailability from premixes‐1 and 2 was similar in the absence of chapatti. However, premix‐2 showed significantly higher iron bioavailability compared to premix‐1 in the presence of chapatti. In contrast, the zinc uptake was similar from both premixes‐1 and 2 in the absence or presence of chapatti. These results suggest that both the premixes provide bioavailable minerals, but premix‐2 appears to be promising in the presence of foods that have high phytate.  相似文献   
99.
100.
A method has been developed to fabricate waveguide-to-waveguide couplers and tapered dielectric rod antennas for the millimeter-wave regime from microetched silicon. A proof-of-concept study shows that the structures can be realized using relatively simple wet etching and robotic process control. Experimental measurements of the waveguide-waveguide couplers agree in key features with simulations. The results indicate that two-stepped tapers perform nearly as well as smooth linear tapers, but are much easier to fabricate. Coupling transmissivity of better than -1 dB, and peak antenna gain of 8-10 dB are indicated at W-band frequencies. Lateral dimension etch control of 5-mum precision was realized. To solve a challenge of controlling the length of the first step, either an improved masking method or a switch to dry etching processes is required.  相似文献   
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