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EM Emery GP Ritter-Randolph AL Strozier RJ McDermott 《Canadian Metallurgical Quarterly》1993,41(5):195-198
Despite extensive efforts to decrease alcohol abuse among college students, prevention approaches have had limited success. This study attempted to clarify reasons for this limited success and to identify directions for future interventions by directly interviewing college students on this topic. Five issues were discussed in the focus group interviews: (1) reasons for drinking alcohol, (2) reasons for not drinking alcohol, (3) circumstances surrounding overconsumption of alcohol, (4) topics and methods for prevention, and (5) gender differences in drinking patterns. The focus group interviews were found to be a valid tool for elucidating sensitive aspects of these issues and the relative importance of these issues to each other. The students revealed how susceptible they are to societal pressures to drink alcohol and how the limitations of their intrapersonal skills affect their alcohol consumption, most notably regarding sexuality issues. The authors contend that improving intrapersonal skills should be a major focus of programs to prevent alcohol abuse. 相似文献
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Modification of the gut flora by dietary means 总被引:1,自引:0,他引:1
Elevated plasma lipoprotein(a) [Lp(a)] is an independent risk factor for several vascular diseases. Lp(a) particles are generated through the formation of a disulfide bond between Cys4057 of kringle IV type 9, (KIVt9), of the multikringle apolipoprotein(a) [apo(a)] and a cysteine in apoB-100 low-density lipoprotein (LDL). To better understand this interaction, we have expressed and purified KIVt9 from Escherichia coli as a His-Tag fusionprotein. Dithiothreitol (DTT)-treated purified KIVt9 migrated as a single approximately 17. 3-kDa band on SDS-PAGE gels. Without DTT, an additional band twice the molecular weight of KIVt9 was observed. The double-size band presumably resulted from dimerization of individual kringles, through their unpaired cysteine residues, since a mutation Cys4057 --> Ser ([Ser4057]KIVt9) abolished dimer formation. Using a gel-shift assay, we showed that KIVt9 could couple to 14-amino-acid apoB-100 synthetic peptides (apoB3732-3745 and apoB4319-4332) containing Cys3734 or Cys4326. Both of these apoB-100 cysteines have been reported to associate with apo(a) to generate Lp(a). In the presence of either apoB-100 peptide, KIVt9 was shifted to a higher molecular weight that was consistent with the covalent addition of a 1.2-kDa apoB-100 peptide. Identical apoB-100 peptides in which the cysteine residues were replaced by alanine ([Ala3734]apoB3732-3745 and [Ala4326]apoB4319-4332) had no effect in the gel-shift assay. Furthermore, [Ser4057]KIVt9 did not covalently interact with apoB3732-3745 or apoB4319-4332. These results indicated that KIVt9 couples to the Cys-apoB-100 peptides through a disulfide linkage. This system may be suitable for further investigating the apo(a)/apoB-100 coupling reaction and the structure of KIVt9 through X-ray crystallographic studies. 相似文献
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Criticisms of the index of citation are presented. Data are cited to bolster the thesis "that the age decrement in outstanding scientific creativity is not an artifact but a fact." Major sections are: The Index of Citation and How It Was Obtained, What Historians of Science Think of the Index of Citation, New Data, and The Findings of Some Outstanding Scholars. "Older men may be more scholarly, but they do not usually exhibit more originality than do younger ones." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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R Michael Lehman Kurt A Rosentrater 《Journal of the science of food and agriculture》2013,93(3):498-503
BACKGROUND: The storability of distillers wet grains (DWG) influences the economic, energetic, and carbon balances of fuel ethanol production, yet there are limited published data on the deterioration of DWG following its production. We used biogenic CO2 production to assess the aerobic stability of DWG incubated at three temperatures (12 °C, 22 °C, 32 °C) and compared CO2 production over time to the appearance of mold and changes in DWG color parameters. RESULTS: CO2 production and mold colonization indicate that at temperatures near 12 °C, the aerobic stability of DWG was high and that it can be stored for at least a 10‐day period. At temperatures close to 22 °C, the onset of increased microbial activity and visible mold colonization occurred between 4 and 7 days and both activity and mold ratings were very high by the ninth day in all three experiments. At 32 °C, 2 days may be a more appropriate limit for storage. CONCLUSION: Temperature and time interact in a nonlinear fashion that permits the prediction of DWG stability boundaries. The simple visual appearance of mold appears to be a reasonable indicator that correlates well (r = 0.694) with CO2 production, a measure of the aerobic stability of DWG. Published 2012 by John Wiley & Sons, Ltd. 相似文献
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CM Balch TM Murad SJ Soong AL Ingalls NB Halpern WA Maddox 《Canadian Metallurgical Quarterly》1978,188(6):732-742
A multifactorial analysis was used to identify the dominant prognostic variables affecting survival from a computerized data base of 339 melanoma patients treated at this institution during the past 17 years. Five of the 13 parameters examined simultaneously were found to independently influence five year survival rates: 1) pathological stage (I vs II, p = 0.0014), 2) lesion ulceration (present vs absent, p = 0.006), 3) surgical treatment (wide excision vs wide excision plus lymphadenectomy, p = 0.024), 4) melanoma thickness (p = 0.032), and 5) location (upper extremity vs lower extremity vs trunk vs head and neck, p = 0.038). Additional factors considered that had either indirect or no influence on survival rates were clinical stage of disease, age, sex, level of invasion, pigmentation, lymphocyte infiltration, growth pattern, and regression. Most of these latter variables derived their prognostic value from correlation with melanoma thickness, except sex which correlated with location (extremity lesions were more frequent on females, trunk lesions on males). This statistical analysis enabled us to derive a mathematical equation for predicting an individual patient's probability of five year survival. Three categories of risk were delineated by measuring tumor thickness (Breslow microstaging) in Stage I patients: 1) thin melanomas (<0.76 mm) were associated with localized disease and a 100% cure rate: 2) intermediate thickness melanomas (0.76-4.00 mm) had an increasing risk (up to 80%) of harboring regional and/or distant metastases and 3) thick melanomas (>/=4.00 mm) had a 80% risk of occult distant metastases at the time of initial presentation. The level of invasion (Clark's microstaging) correlated with survival, but was less predictive than measuring tumor thickness. Within each of Clark's Level II, III and IV groups, there were gradations of thickness with statistically different survival rates. Both microstaging methods (Breslow and Clark) were less predictive factors in patients with lymph node or distant metastases. Clinical trials evaluating alternative surgical treatments or adjunctive therapy modalities for melanoma patients should incorporate these parameters into their assessment, especially in Stage I (localized) disease where tumor thickness and the anatomical site of the primary melanoma are dominant prognostic factors. 相似文献
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