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101.
We demonstrate a strategy for microfabricating catalytically active, three-dimensional matrixes composed of cross-linked protein in cellular and microfluidic environments. In this approach, a pulsed femtosecond laser is used to excite photosensitizers via multiphoton absorption within three-dimensionally defined volumes, a process that promotes cross-linking of protein residue side chains in the vicinity of the laser focal point. In this manner, it is possible to fabricate protein microparticles with dimensions on the order of the multiphoton focal volume (less than 1 microm(3)) or, by scanning the position of a laser focal point relative to a specimen, to generate surface-adherent matrixes or cables that extend through solution for hundreds of micrometers. We show that protein matrixes can be functionalized either through direct cross-linking of enzymes, by decoration of avidin matrixes with biotinylated enzymes, or by cross-linking biotinylated proteins that then are linked to biotinylated enzymes via an avidin couple. Several formats are explored, including microparticles that can be translocated to desired sites of action (including cytosolic positions), protein pads that generate product gradients within cell cultures, and on-column nanoreactors for microfluidic systems. These biomaterial fabrication technologies offer opportunities for studying a variety of cell functions, ranging from single-cell biochemistry and development to perturbation and analysis of small populations of cultured cells. 相似文献
102.
Systematic root cause analysis of adverse drug events in a tertiary referral hospital 总被引:3,自引:0,他引:3
Rex JH Turnbull JE Allen SJ Vande Voorde K Luther K 《The Joint Commission journal on quality improvement》2000,26(10):563-575
BACKGROUND: Adverse drug events (ADEs) occur frequently, and serious ADEs are associated with mortality or prolonged morbidity. As many ADEs are preventable, identification and modification of systems and processes that permit ADEs has the potential to reduce the rate of ADEs. METHODS: Root cause analysis was systematically employed in a blame-free fashion to investigate the patterns of serious ADEs that occurred during a 29-month period at Hermann Hospital (Houston), and process improvements were implemented on the basis of these findings. The consistently nonpunitive responses to the results of the initial and subsequent root cause analyses was gradually seen, accepted, and ultimately embraced by the hospital staff. RESULTS: The most commonly identified root causes were environmental factors (for example, increased census, increased acuity, change of shift) and staffing issues (for example, personnel new to a unit). Policy changes that led to increased use of forcing or constraining functions (for example, removal of concentrated intravenous potassium solutions from floor stocks) and better personnel support (for example, early awareness and response to localized increases in census and acuity) were particularly effective. Although limited by our lack of active surveillance and not necessarily directly due to the process changes that we implemented, the rate of voluntarily reported serious ADEs/100,000 patient days decreased during this time from 7.2 to 4.0, a decline of 45% (p < 0.001). CONCLUSION: Systematic application of root cause analysis followed by implementation of process changes that target the underlying cause(s) of each event can be successfully implemented in a large hospital. 相似文献
103.
Examined the efficacy of incorporating formal training in social learning principles into a behavioral parent training program as a means of enhancing treatment outcome and generalization. Two groups of parents (n?=?20) received behavioral skill training designed to modify child noncompliance. One group also received formal training in social learning principles throughout the program. Children had a mean age of 61.75 mo. Outcome measures collected prior to and after treatment and at a 2-mo follow-up included home observations by independent observers, parents' perceptions of child adjustment, and a parent consumer-satisfaction measure. Results indicate that after treatment, the group receiving social learning principles tended to perceive their children as better adjusted and tended to be more satisfied with treatment. At follow-up, parents in this group perceived their children as better adjusted and rewarded their children more. Furthermore, their children were significantly more compliant. Results suggest that temporal and setting generality are enhanced by the inclusion of social learning principles into parent training procedures. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Lahey Benjamin B.; Hammer David; Crumrine Paula L.; Forehand Rex L. 《Canadian Metallurgical Quarterly》1980,16(6):608
The 1st of 2 experiments examined the referral rates of children to a psychology clinic. Only 2-child families were studied to avoid confounds related to family size. A multiple-contingency analysis of the frequency of referral showed a significant effect for sex, birth order, and a Sex by Birth Order interaction. Further analyses of the interaction showed there was a sex difference only among firstborns and a birth order effect only among males. In Exp II, preschool teachers who were blind to the variables under study rated 83 children from 2-child families on the Behar Preschool Behavior Questionnaire. Results of statistical analysis show no significant main effects for birth order, and a significant effect for sex was found only for the Hyperactive-Distractible factor of the questionnaire. Significant interactions between sex and birth order were found, however, for all factors (Hostile-Aggressive, Anxious-Fearful, Hyperactive-Distractible, and total score). As in Exp I, firstborn males were rated higher on all 4 scores than any other group. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
A. M. Gaddis Rex Ellis Jennie Shamey G. T. Currie 《Journal of the American Oil Chemists' Society》1965,42(7):620-624
Comparison of quantitative methods for the isolation of aldehydes from lard oxidized at 23C showed an extreme sensitivity
of precursors to isolation conditions. Differences existed in the quantity and class compositions of the monocarbonyl compounds
isolated. Acid conditions caused considerable breakdown of alkanal and alk-2-enal precursors. Steam distillation (100C) released
alkanals, alk-2-enals, and alk-2,4-dienals. The mild Girard T method apparently produced a small amt of alk-2-enals from precursors,
but except in the initial stages isolated the lowest amounts of aldehydes. Complete evaluation of the method for isolation
of free aldehydes was not possible because alkanals were released from precursors during the vacuum distillation procedure
(50C). The Schwartz (dilute phosphoric acid), Girard T, and vacuum distillation methods isolated similar amounts of alk-2,4-dienals.
Curious changes in relationships, possibly indicative of oxidation stages, were observed as autoxidation progressed. 相似文献
106.
107.
Rex D. Cole Juei-Ho. Liu Gerard V. Smith Conrad C. Hinckley Mykola Saporoschenko 《Fuel》1978,57(9):514-520
Oil shale of the Green River Formation (Eocene) in the Piceance Creek Basin, Colorado contains seven major iron-bearing minerals: pyrite, marcasite, pyrrhotite, Mg-siderite, Fe-dolomite, ankerite and Ca-ankerite. Only recently have workers recognized that these rocks contain large quantities of iron-bearing carbonate minerals. Preliminary Mössbauer spectroscopy analysis of four oil-shale and two marlstone samples from the Green River Formation shows that the dominant iron-bearing compound is usually an iron-carbonate mineral, generally Ca-ankerite or Fe-dolomite. The second most abundant iron-bearing phase is an iron sulphide, generally pyrite. In the samples studied, the iron partitioning is variable between the carbonate and sulphide phases. Lower grades of oil shale and marlstone also have an iron-bearing silicate phase, which is perhaps an iron-bearing phyllosilicate, possibly chlorite. 相似文献
108.
109.
Monoenoic acid fractions were isolated from phosphatidylcholines, phosphatidylethanolamines, triglycerides, and cholesterol
esters derived from minimal deviation hepatoma 7288C cells cultured on 11 media containing varying levels of serums and lipids.
Hexadecenoate (16∶1), octadecenoate (18∶1), and eicosenoate (20∶1) fractions were subjected to ozonolysis and the isomeric
composition of the monoene fractions determined quantitatively by gas liquid chromatography. The 16∶1 fractions consisted
of palmitoleic acid, the Δ9 isomer (85–90%), and the Δ11 isomer (10–15%) in most of the cases; growth media and lipid class
origin had little effect upon composition. The predominate acids of the 20∶1 fraction were the Δ13 and Δ11 isomers. Generally,
the Δ13 isomer was present in the highest concentration, and this isomer was higher in phosphatidylcholines than the other
classes. Vaccenic acid represented 33–66% of the 18∶1 fraction, and the balance was oleic acid. Oleic acid concentrations
decreased, and vaccenic acid levels increased as the growth medium serum and lipid levels decreased. Lipid classes did not
exhibit any distinct preference for either isomer. These data represent the first quantitative isomeric analysis of monoenoic
acids derived from individual lipid classes and are the first to show the occurrence of high levels of vaccenic acid in neoplastic
cells. This study suggests that the elevated levels of oleic acid, one of the most frequently observed changes in tumor lipids,
may, in fact, represent elevated levels of vaccenic acid. 相似文献
110.
The effect of dietary cyclopropene fatty acids on the concentration of octadecenoate chain positional isomers in individual
lipid classes of normal liver, host liver, and hepatoma 7288CTC has been determined. The data revealed the following: (a)
Saturated and monoene fatty acid percentages of liver phosphatidylcholines and phosphatidylethanolamines werenot affected, but the percentage of saturated fatty acids of the triglycerides and cholesteryl esters was increased while the
monoene percentages decreased. (b) Oleate to vaccenate percentage ratios, previously shown to be characteristic of individual
lipid classes, were completely disrupted. (c) Oleate concentrations of the two major liver phospholipids were elevated, and
vaccenate levels were dramatically reduced. (d) Cyclopropene fatty acids appear to inhibit monoene elongation. (e) The elevated
concentrations of oleate indicate that an alternate route of oleate biosynthesis must exist if the Δ9 desaturation is inhibited
by cyclopropene fatty acids as reported previously. (f) In contrast to liver, oleate and vaccenate concentrations in hepatoma
were not affected by the dietary cyclopropene fatty acids. 相似文献