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71.
Amprenavir (141W94, VX-478, KVX-478) is metabolized primarily by CYP3A4 (cytochrome P450 3A4) in recombinant systems and human liver microsomes (HLM). The effects of ketoconazole, terfenadine, astemizole, rifampicin, methadone, and rifabutin upon amprenavir metabolism were examined in vitro using HLM. Ketoconazole, terfenadine, and astemizole were observed to inhibit amprenavir depletion, consistent with their known specificity for CYP3A4. The HIV protease inhibitors, indinavir, saquinavir, ritonavir, and nelfinavir, were included in incubations containing amprenavir to examine the interactions of HIV protease inhibitors in vitro. The order of amprenavir metabolism inhibition in human liver microsomes was observed to be: ritonavir > indinavir > nelfinavir > saquinavir. The Ki value for amprenavir-mediated inhibition of testosterone hydroxylation in human liver microsomes was found to be approximately 0.5 microM. Studies suggest that amprenavir inhibits CYP3A4 to a greater extent than saquinavir, and to a much lesser extent than ritonavir. Amprenavir, nelfinavir, and indinavir appear to inhibit CYP3A4 to a moderate extent, suggesting a selected number of coadministration restrictions. 相似文献
72.
73.
Presents an obituary for Joseph B. Margolin. In the 1940s, Margolin was in the U.S. Army Signal Corps. During that period, he was stationed at an Army hospital in California, and it was there that he developed an interest in clinical psychology. After being discharged, he returned to New York, where he received his doctorate in clinical and social psychology from New York University in 1954. He was always interested in combining his clinical activities with professional and political involvement, and held several positions including president of the District of Columbia Psychological Association, chair of the Maryland Board of Examiners for Psychologists, and staff member of the 1960 White House Conference on Children and Youth. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
An adaptive nulling algorithm for adjusting the array weights under the soft constraint of the weight norm being very much less than 1 or equal to 1, based on the measured correlations between the array and element outputs, is described. The algorithm can be regarded as an extension of the constrained least-mean-square algorithm. It is derived from the same concept of signal and noise subspaces defined in the multiple signal classification (MUSIC) algorithm. One of the unique features of the present algorithm is that the number of the iterations required to adapt the array weights to form nulls is exactly equal to the number of interferers 相似文献
75.
1 . INTRODUCTIONHigh speedliquidjetsareoftenseeninrainerosionsimulationofaircraftandmissiles ,JilbertandField[1] and jetcuttingofmaterials ,Kob ayashi[2 ] .Inthegenerationofjets ,itistechnicallyinterestingtoknowhowtooperatetheexperimen talfacilityattheoptimumconditiontoobtainthejetvelocitymostefficiently .ThisisdescribedbyShiandTakayama[3] ,ShiandItoh[4 ] ,ShiandIt oh[5] .Intheearlieststudyofa pulsedhigh speedliquidjet ,BowdenandBrunton[6 ] puttheliquidinanozzleandthenusedaslugimpact… 相似文献
76.
Replicated R. E. Carlson's (see record 1971-21928-001) study of the effects of favorability, order, and type of information on interviewers' decisions. Raters were 80 psychology students in introductory and upper-level courses. Results showed that unfavorable information was more important to interviewers' ratings than favorable information. However, this effect was moderated by the expected typical applicant-an applicant of high caliber leading to a more favorable 1st impression of unfavorable information. Unfavorable information showed contrast effects moderated by the type of information. Interviewers' confidence in evaluations was greater for favorable than for unfavorable information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
A hybrid-mode model is developed which allows analytical calculation of the leaky-mode loss coefficient in Ti-diffused LiNbO3 waveguides. Field representations correspond to the approximation of geometrical optics. Hybrid-mode effective indexes are approximated utilizing the known anisotropy of LiNbO3 . ForX - orY -cut waveguides the leaky mode is shown to be an extraordinary-like hybrid mode with a small ordinary field component which arises from extraordinary to ordinary power conversion at the abrupt index boundary. This ordinary index component is not bound by the graded index boundary, giving rise to the power loss. The theoretical dependence of the loss coefficient on propagation direction is in agreement with experiment. 相似文献
78.
JL You SC Milton RC Milton NS Rangaraju RB Harris 《Canadian Metallurgical Quarterly》1993,12(2):133-141
Homogeneous pre-pro-GnRH/GAP protein was recently synthesized in 100 mg quantities by solid-phase methods and surprisingly, the synthetic pre-pro-protein, which normally does not escape the endoplasmic reticulum, was found to inhibit the release of prolactin from cultured pituitary cells. This is the first demonstration of significant biological activity associated with a precursor protein and provides the rationale for its further study. We now report the results of our initial examination of the conformational properties of pre-pro-GnRH/GAP protein as a prelude to solving its solution phase conformation by homonuclear 1H-NMR protocols. Thermal and pH titration fluorescence and circular dichroism spectroscopies reveal that the protein is resistant to thermal-induced conformational changes but is particularly sensitive to pH-induced conformational changes; while Asp/Glu and Arg residues may contribute to structural stability, His and Lys residues predominate. Pre-pro-GnRH/GAP is about 30% helix in the range of 2-40 degrees C; however, even at 90 degrees C, the peptide retains nearly 50% of its helix character. There is no evidence for a cooperative transition; for this reason, differential scanning calorimetry failed to yield a defined transition thermogram. Pre-pro-GnRH/GAP apparently does not pass through a transition state as a function of temperature but appears to flex and retain a high percentage of helix structure, resulting in subtle changes in secondary structure. There is no discernible isodichroic point. On either side of the neutral pH range, however, there are dramatic changes in structure that result in nonreversible denaturation of the protein.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
79.
Recently, while visiting another science laboratory the author was given a glossary of phrases commonly used in scientific reports. Sure that all psychologists who read and write research reports are interested in maximizing "communication," the author cheerfully offers an abridged guide for use with psychological literature. Perhaps other psychologists can suggest additional definitions which will increase enlightenment. An example: What he said: "It has long been known that . . ." and what he meant: "I haven't bothered to look up the original reference but . . .." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.