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61.
Blanchard Kimberly A.; Morgenstern Jon; Morgan Thomas J.; Lobouvie Erich W.; Bux Donald A. 《Canadian Metallurgical Quarterly》2003,17(4):328
Negative consequences are an important component of the substance use change process, yet no standardized measure exists to assess consequences of use. This study evaluated the psychometric properties of the Inventory of Drug Use Consequences, a self-report measure assessing drinking and drug use consequences. Participants (N=252) were assessed at entry into outpatient substance abuse treatment. Items loaded strongly on 1 factor, and internal consistency of the total scale was high. Fifteen items with the highest correlations with the total scale were chosen to represent the construct. The shortened measure exhibited good internal consistency, convergent and discriminant validity, and detected change over time and may be the measure of substance use consequences that is lacking in the field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
KR Kaderlik GJ Mulder RJ Turesky NP Lang CH Teitel MP Chiarelli FF Kadlubar 《Canadian Metallurgical Quarterly》1994,15(8):1695-1701
The food-borne carcinogenic and mutagenic heterocyclic aromatic amines undergo bioactivation to the corresponding N-hydroxy (OH)-arylamines and the subsequent N-glucuronidation of these metabolites is regarded as an important detoxification reaction. In this study, the rates of glucuronidation for the N-OH derivatives of 2-amino-3-methylimidazo[4,5-f]-quinoline (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine (PhIP), 2-amino-6-methyl-dipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) by liver microsomal glucuronosyltransferase were compared to that of the proximate human urinary bladder carcinogen, N-OH-aminobiphenyl (N-OH-ABP) and the proximate rat colon carcinogen N-OH-3,2'-dimethyl-4-amino-biphenyl (N-OH-DMABP). Human liver microsomes catalyzed the uridine 5'-diphosphoglucuronic acid (UDPGA)-dependent glucuroidation of N-OH-IQ, N-OH-PhIP, N-OH-Glu-P-1 and N-OH-MeIQx at rates of 59%, 42%, 35% and 27%, respectively, of that measured for N-OH-ABP (11.5 nmol/min/mg). Rat liver microsomes also catalyzed the UDPGA-dependent glucuronidation of N-OH-PhIP, N-OH-Glu-P-1 and N-OH-IQ at rates of 30%, 20% and 10%, respectively of that measured for N-OH-DMABP (11.2 nmol/min/mg); activity towards N-OH-MeIQx was not detected. Two glucuronide(s) of N-OH-PhIP, designated I and II, were separated by HPLC. Conjugate II was found to be chromatographically and spectrally identical with a previously reported major biliary metabolite of PhIP in the rat, while conjugate I was identical with a major urinary metabolite of PhIP in the dog. Hepatic microsomes from rat, dog and human were found to catalyze the formation of both conjugates. The rat preferentially formed conjugate II (I to II ratio of 1:15), while the dog and human formed higher relative amounts of conjugate I (I to II ratio of 2.5:1.0 and 1.3:1.0 respectively). Fast atom bombardment mass spectrometry of conjugates I and II gave the corresponding molecular ions and showed nearly identical primary spectra. However, collision-induced spectra were distinct and were consistent with the identity of conjugates I and II as structural isomers. Moreover, the UV spectrum of conjugate I exhibited a lambda max at 317 nm and was essentially identical to that of N-OH-PhIP, while conjugate II was markedly different with a lambda max of 331 nm. Both conjugates were stable in 0.1 N HCl and were resistant to hydrolysis by rat, dog and human liver microsomal beta-glucuronidases.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
63.
Juice-extracted grass pellets and sodium bicarbonate for cows fed timothy silage of two chop lengths
Eighteen multiparous Holstein cows in midlactation were used in a switchback design trial to evaluate the effect of chop length (3 or 30 mm) of timothy grass silage, containing less than 30% ADF and treated with formic acid, on DMI and cow performance. Within chop length, addition of NaHCO3 (2% of DMI) or the replacement of 30% of silage DM with juice-extracted grass pellets was also evaluated. Cows were fed a TMR composed of 90% silage and 10% concentrate. Silage preservation characteristics were not different between chop lengths. The DMI and apparent digestibility were similar among treatments. Yields of 4% FCM (24.9 vs. 22.7 kg/d), fat (1.03 vs. .93 kg/d), and protein (.83 vs .77 kg/d) were higher with the short chopped silage. Milk protein, milk NPN content, and serum urea were higher for cows fed long chopped silage. Yields of milk and milk constituents were not affected by the addition of juice-extracted grass pellets or NaHCO3. Fat percentage and fatty acid composition of milk remained unchanged by treatments. Reduction of particle size, from 30 to 3 mm, of timothy grass, treated with formic acid at harvest and using compaction at ensiling in bag silos, did not affect silage conservation characteristics but did improve milk, fat, and protein yields when cows were fed high silage diets. 相似文献
64.
H Yokoyama R Momeni C Goldstein M Mohiuddin Z Shen BS Fyfe GJ Whitman VJ DiSesa 《Canadian Metallurgical Quarterly》1996,62(11):1540-1543
BACKGROUND: Vesnarinone (VES) has been used for treatment of patients with congestive heart failure. In addition to inotropic effects, it seems to have immunosuppressive action. We tested the hypothesis that VES suppresses graft rejection, inotropic dysfunction caused by early rejection, and chronic coronary obstruction in a heterotopic rat cardiac transplantation model. METHODS: (1) To study acute rejection, hearts from Lewis-Brown Norway (LBN) rats were transplanted into Lewis rats, which were treated with or without VES (50 or 100 mg/kg/day orally). (2) In a functional study, LBN hearts with or without VES (100 mg/kg/ day) were isolated and perfused on day 3 after transplantation to assess inotropic response to isoproterenol (3 x 10(-8) M). (3) To study chronic rejection, Lewis hearts were transplanted into Fisher 344 rats, which were treated with or without VES (50 mg/kg/day) for 90 days. Coronary obstructive disease was assessed by morphometric analysis. There were five to six animals in each group. RESULTS: (1) VES (100 mg/kg/day) prolonged LBN heart survival (11.7 +/- 0.7 vs. 9.6 +/- 0.7 days in control; P < 0.05). (2) Left ventricular developed pressure was depressed in transplanted hearts regardless of VES treatment (84 +/- 12, 90 +/- 8 vs. 144 +/- 16 mmHg in untransplanted hearts; P < 0.01). The developed pressure after administration of isoproterenol in VES-treated hearts (184 +/- 20 mmHg) was higher than transplanted hearts without VES (118 +/- 16 mmHg; P < 0.05), and similar to untransplanted hearts (203 +/- 27 mmHg; P = NS). (3) Transplanted hearts treated with or without VES showed similar grades of rejection (2.0 +/- 0.3 vs. 2.6 +/- 0.2; P = NS), intimal area (6,996 +/- 3,186 vs. 13,441 +/- 5,165 microns2; NS), and coronary luminal obstruction (45 +/- 16% vs. 67 +/- 14%; NS). CONCLUSIONS: VES produces mild prolongation in survival of rat heart grafts, but has no significant effect on chronic graft atherosclerosis. VES preserves the positive inotropic effects of isoproterenol that are otherwise deteriorated by early acute rejection. 相似文献
65.
The effect of thermal annealing on the electrical and optical characteristics of ITO films prepared by reactive sputtering and thermal evaporation have been studied. The effect of the thermal annealing is to improve the conductivity and the optical transmission in the shorter wavelength region. The conductivity of the films increases with annealing temperature, this behaviour is associated with grain growth in the film. 相似文献
66.
J Benbassat G Zajicek GJ van Oortmarssen I Ben-Dov MH Eckman 《Canadian Metallurgical Quarterly》1993,13(3):237-244
Cell cultures were derived from adult human brain biopsies [from cortical gray (cultures 9-HB-G and 33-HB-G) and white (culture 14-HB-W) and stroke-injured white matter (culture 33-HB-IW)]. The morphology and growth rate of cultured cells were examined and correlated with the presence of vimentin and glial fibrillary acidic protein (GFAP). The cultures from various brain matters differed in cell morphology and rate of growth but not in GFAP and vimentin staining. Cells of primary and rapidly proliferating cultures were GFAP-negative and vimentin-positive. Spontaneous growth deceleration occurred in culture 14-HB-W within passages 5 to 10 and in cultures 9-HB-G, 33-HB-G, and 33-HB-W within passages 17 to 20. This deceleration, as well as the successive complete growth arrest, were accompanied by an appearance of GFAP-positive cells and an elevated intensity for vimentin staining. We propose that GFAP-positive astrocytes originate from glial precursor cells that migrate from the explants and differentiate under prolonged subcultivation. 相似文献
67.
M Albert C Athanassopoulos LB Auerbach D Bauer R Bolton B Boyd RL Burman I Cohen DO Caldwell BD Dieterle JB Donahue AM Eisner A Fazely FJ Federspiel GT Garvey RM Gunasingha V Highland J Hill R Imlay K Johnston WC Louis A Lu AK Mann J Margulies K McIlhany W Metcalf RA Reeder V Sandberg M Schillaci D Smith I Stancu W Strossman MK Sullivan GJ VanDalen W Vernon YX Wang DH White D Whitehouse D Works Y Xiao S Yellin 《Canadian Metallurgical Quarterly》1995,51(3):R1065-R1069
68.
69.
Eigenmode expansions are used for computing the currents on a dielectric loaded top-hat monopole radiating above an infinite conducting ground plane. The approach is facilitated by adding a parallel ground plane above the antenna, thus allowing use of cylindrical harmonic field expansions in each of three regions. Expansion coefficients are found by enforcing boundary and continuity conditions at conducting surfaces and regional interfaces. Convergence and accuracy are assessed using comparisons with three other methodologies, namely an integral equation solution, a quasi-static analysis, and multi-octave experimental measurements 相似文献
70.
We discuss the surgical approach used for and outcome in 11 infants (< or =3 years) who were treated at our institution for ependymomas arising in the cerebellar-pontine (C-P) angle. The median age of the group was 19 months (range: 6-26 months). Of these 11 patients, the initial surgery for 8 was performed at our center and achieved a gross total resection (GTR) in 4 patients and a subtotal resection (STR) in the remaining 4. The 3 patients who had tumor debulking performed elsewhere were subsequently referred to our institution and had definitive surgery after receiving 3-4 courses of chemotherapy; one of these children had a GTR, whereas the remaining 2 had an STR. During the immediate postoperative period, 9 patients had cranial nerve deficits that necessitated placement of a tracheostomy and a gastrostomy feeding tube; these were discontinued in 6 of the 9 patients as the deficits resolved. The majority of the permanent cranial nerve deficits involved the sixth and seventh cranial nerves. Of the 11 patients, 4 have died (progressive disease, n = 1; accidental death, n = 2; withdrawal of life support, n = 1); the remaining 7 patients are alive, with a median follow-up of 37 months (range: 20-73 months). Aggressive surgical resection for tumors arising in the C-P region is associated with postoperative deficits, which resolve over time with appropriate supportive care. This approach may increase the number of children in whom GTR is achieved, thereby potentially increasing the cure rate for these patients. 相似文献