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61.
Morgenstern Jon; Irwin Thomas W.; Wainberg Milton L.; Parsons Jeffrey T.; Muench Frederick; Bux Donald A. Jr.; Kahler Christopher W.; Marcus Susan; Schulz-Heik Jay 《Canadian Metallurgical Quarterly》2007,75(1):72
This study tested the efficacy of behavioral treatments for alcohol use disorders (AUD) among men who have sex with men (MSM) and who are at risk for HIV transmission. HIV-negative MSM with current AUD (N = 198) were recruited, offered treatment focused on reducing drinking and HIV risk, and followed during treatment and 12 months posttreatment. Participants (n = 89) accepted treatment and were randomized to either 4 sessions of motivational interviewing (MI) or 12 sessions of combined MI and coping skills training (MI + CBT). Other participants (n = 109) declined treatment but were followed, forming a non-help-seeking group (NHS). MI yielded significantly better drinking outcomes during the 12-week treatment period than MI + CBT, but posttreatment outcomes were equivalent. NHS participants significantly reduced their drinking as well. Service delivery and treatment research implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
MH Kolk M van der Graaf CT Fransen SS Wijmenga CW Pleij HA Heus CW Hilbers 《Canadian Metallurgical Quarterly》1998,17(24):7498-7504
The solution structure of an RNA-hairpin present in the pseudoknot, which is found at the 3'-terminus of turnip yellow mosaic virus genomic RNA, has been solved by nuclear magnetic resonance spectroscopy. The loop, which contains the sequence 5'-GGGUCA-3', was found to be highly structured and, contrary to expectations, does not attain its stability through GA or GC base pair formation but by triple interactions between the tilted adenosine and the minor groove sides of the first two guanosines. Interestingly, a very similar conformation was found for the cognate pseudoknot, implying that the 3'-hairpin is preformed for folding into a pseudoknotted structure. These findings suggest a mechanism of 'predetermined-fit' as a principle in RNA folding. 相似文献
63.
64.
Sexual coercion, a topic of relevance to school health personnel, may be as common in high school populations as in university populations. Twenty-one sexuality education curricula were examined for information on the topics of date rape, stranger rape, pressure, incest, sexual harassment, unwanted/inappropriate touch, and exploitation/victimization. Curricula scoring highest in total coverage also were the most comprehensive with six of the seven sexual coercion topics covered. Overall, pressure and exploitation/victimization received the greatest attention, while sexual harassment was not covered in any of the curricula. Common themes occurring within the coercion topic areas included guilt, communication/assertiveness skills, blame, drug use, premeditation, fear, sources of help. Results suggest sexuality education curricula have not responded to the increased concern regarding sexual harassment in schools. 相似文献
65.
66.
TR DeGrado TG Turkington JJ Williams CW Stearns JM Hoffman RE Coleman 《Canadian Metallurgical Quarterly》1994,35(8):1398-1406
METHODS: This study characterizes the performance of a newly developed whole-body PET scanner (Advance, General Electric Medical Systems, Milwaukee, WI). The scanner consists of 12,096 bismuth germinate crystals (4.0 mm transaxial by 8.1 mm axial by 30 mm radial) in 18 rings, giving 35 two-dimensional image planes through an axial field of view of 15.2 cm. The rings are separated by retractable tungsten septa. Intrinsic spatial resolution, scatter fraction, sensitivity, high count rate performance and image quality are evaluated. RESULTS: Transaxial resolution (in FWHM) is 3.8 mm at the center and increases to 5.0 mm tangential and 7.3 mm radial at R = 20 cm. Average axial resolution decreases from 4.0 mm FWHM at the center to 6.6 mm at R = 20 cm. Scatter fraction is 9.4% and 10.2% for direct and cross slices, respectively. With septa out, the average scatter fraction is 34%. Total system sensitivity for true events (in kcps/(microCi/cc)) is 223 with septa in and 1200 with septa out. Dead-time losses of 50% correspond to a radioactivity concentration of 4.9 (0.81) microCi/cc and a true event count rate of 489 (480) kcps with septa in (out). Noise-equivalent count rate (NECR) for the system as a whole shows a maximum of 261 (159) kcps at a radioactivity concentration of 4.1 (0.65) microCi/cc with septa in (out). NECR is insensitive to changes in lower gamma-energy discrimination between 250-350 keV. CONCLUSIONS: The results show the performance of the newly designed PET scanner to be well suited for clinical and research applications. 相似文献
67.
TY Chen ST Lee TN Lui CW Wong YS Yeh WC Tzaan SY Hung 《Canadian Metallurgical Quarterly》1997,48(5):435-40; discussion 441
BACKGROUND: Controversy surrounds the treatment of traumatic central cord syndrome (TCCS), as there are strong advocates for nonsurgical treatment for most patients. However, conservative treatment has been shown to yield a longer period of discomfort from pain and weakness in certain cases. METHODS: In a retrospective review of 114 patients presenting with acute or chronic TCCS from 1988-94, four different age groups were separately observed under different treatments. Motor and sensory recovery were assessed. RESULTS: Better results were achieved in younger patients, with or without radiographic abnormalities, and in patients with clinically correlated encroaching cord lesions who received early surgical decompression. CONCLUSIONS: Surgical intervention for TCCS must be addressed with careful clinical and radiographic survey. Removal of offending lesions in the subacute period results in significant motor and sensory improvement in short-term and long-term follow-up. 相似文献
68.
Richard A Brown Raymond Niaura Elizabeth E Lloyd-Richardson David R Strong Christopher W Kahler Ana M Abrantes David Abrams Ivan W Miller 《Nicotine & tobacco research》2007,9(7):721-730
This study is a randomized, double-blind, placebo-controlled clinical trial examining the effects of an intensive cognitive-behavioral mood management treatment (CBTD) and of bupropion, both singularly and in combination, on smoking cessation in adult smokers. As an extension of our previous work, we planned to examine the synergistic effects of CBTD and bupropion on smoking cessation outcomes in general and among smokers with depression vulnerability factors. Participants were 524 smokers (47.5% female, M (age) = 44.27 years) who were randomized to one of four 12-week treatments: (a) standard, cognitive-behavioral smoking cessation treatment (ST) plus bupropion (BUP), (b) ST plus placebo (PLAC), (c) standard cessation treatment combined with cognitive-behavioral treatment for depression (CBTD) plus BUP, and (d) CBTD plus PLAC. Follow-up assessments were conducted 2, 6, and 12 months after treatment, and self-reported abstinence was verified biochemically. Consistent with previous studies, bupropion, in comparison with placebo, resulted in better smoking outcomes in both intensive group treatments. Adding CBTD to standard intensive group treatment did not result in improved smoking cessation outcomes. In addition, neither CBTD nor bupropion, either alone or in combination, was differentially effective for smokers with single-past-episode major depressive disorder (MDD), recurrent MDD, or elevated depressive symptoms. However, findings with regard to recurrent MDD and elevated depressive symptoms should be interpreted with caution given the low rate of recurrent MDD and the low level of depressive symptoms in our sample. An a priori test of treatment effects in smokers with these depression vulnerability factors is warranted in future clinical trials. 相似文献
69.
K Papadakis FI Luks ME De Paepe GJ Piasecki CW Wesselhoeft 《Canadian Metallurgical Quarterly》1997,32(2):347-351
We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE. Thus, the age-dependent and coordinate diminution in cell proliferative activity and cell death events may serve to maintain the thickness of the OE as mice mature and age. 相似文献
70.
Dual-energy x-ray absorptiometry of raloxifene effects on the lumbar vertebrae and femora of ovariectomized rats 总被引:1,自引:0,他引:1
M Sato C McClintock J Kim CH Turner HU Bryant D Magee CW Slemenda 《Canadian Metallurgical Quarterly》1994,9(5):715-724
A new potential therapeutic agent for postmenopausal osteoporosis, raloxifene, previously known as keoxifene, was evaluated by x-ray densitometry and more traditional techniques in quantitating the short-term (4-5 weeks) effects of ovariectomy on bones from 6-month-old rats. A Hologic QDR 1000/W and, to a limited extent, a Lunar DPXL, was used to quantitate ovariectomy, estrogen replacement, and raloxifene effects on vertebrae, femora, and tibiae. Both instruments performed well with precisions of 1.6% (Hologic) and 0.9% (Lunar) for anesthetized rats, which improved to 0.4% (Hologic) and 0.5% (Lunar) when the same rats were frozen. The lumbar vertebrae L1-4 showed a 12% decrease in bone mineral density 4 weeks after ovariectomy, compared with a 9% decrease for femora. Tibiae were also examined, but edge-detection problems prevented reproducible analysis of this site in vivo. The decrease in bone mineral density postovariectomy, especially for femora, was found to include both an increase in the projected area and a slight but not significant decrease in the bone mineral content of L1-4 and femora. These changes in density parameters of femora were supported by a decrease in dry weight and volume and a marginal increase in the second moment of inertia I for the identical femora examined ex vivo. Examination of individual lumbar vertebrae L1-5 suggested that the bone mineral density of L3 changes most dramatically in response to ovariectomy, but present techniques lack the spatial resolution and precision to quantitate bone changes reliably in individual vertebrae. 17 beta-Estradiol administered at 100 micrograms/kg/day subcutaneously inhibited ovariectomy effects on L1-4 bone mineral density, femoral moment of inertia, dry weight, and volume and to a lesser extent, femoral bone mineral density. A nonsteroidal compound, raloxifene HCl, at 1 mg/kg/day per os, had bone effects and effects on body weight that were largely indistinguishable from those of 17 beta-estradiol; however, raloxifene did not produce the uterotrophic effects observed with estrogen. The half-maximal efficacious dose of raloxifene on L1-4 bone mineral density was between 0.1 and 1.0 mg/kg/day per os. These data show that dual-energy x-ray absorptiometry compares favorably with traditional methods in quantitating bone changes caused by ovariectomy in small rodents, that L1-4 is a more sensitive region than whole femora in evaluating the effect of estrogen deficiency on bone loss, and the raloxifene may have promise as a treatment for conditions characterized by excessive bone loss after ovariectomy. 相似文献