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41.
This article describes the development and pilot evaluation of a tailored multimedia program to improve dietary behavior among 378 low-income women enrolled in the Food Stamp program in Durham, North Carolina. After randomization to intervention or control groups, participants completed a baseline survey and were resurveyed 1-3 months post-intervention. Measures included dietary fat intake assessed using a brief food-frequency questionnaire, stage of change, knowledge of low-fat foods, self-efficacy and eating behavior questions. The computer-based intervention consisted of a tailored soap opera and interactive 'info-mercials' that provided individualized feedback about dietary fat intake, knowledge and strategies for lowering fat based on stage of change. At follow-up, intervention group participants had improved significantly in knowledge (P < 0.001), stage of change (P < 0.05) and certain eating behaviors (P < 0.05) compared to the control group. Both study groups had lowered their reported fat intake markedly at follow-up (P < 0.001), but did not differ significantly from each other. A majority of participants rated the program as very helpful and were interested in using a similar program in the future. The findings of this pilot study suggest that computerized tailored self-help health promotion programs may be effective educational interventions for lower income and minority populations.  相似文献   
42.
Racemic methyl 1,4-dihydro-2, 6-dimethyl-5-nitro-4-(benzofurazanyl)pyridine-3-carboxylates (+/-)-10 and (+/-)-11 and their benzofuroxanyl analogues (+/-)-12 and (+/-)-13 were prepared using a modified Hantzsch reaction that involved the condensation of nitroacetone with methyl 3-aminocrotonate and the appropriate aldehydes. The racemic mixtures were resolved into the corresponding enantiomers. Whole-cell voltage-clamp studies on L-type Ca2+ channels expressed in a rat insulinoma cell line (RINm5F) showed that all the dextrorotatory antipodes were effective agonists of L-type Ca2+ currents, while the levorotatory ones were weak Ca2+ entry blockers. The (+)-enantiomer of benzofurazan-5'-yl derivative 11 demonstrated unusual activity in that, in addition to producing a potentiation of L-type currents, it interfered with the voltage-dependent gating of L-type channels by producing a net delay of their activation at low voltages. This compound represents an interesting tool to probe L-type Ca2+ channel structure and function.  相似文献   
43.
Investigation of vesico-urethral and sweating function was performed in twelve patients with classical idiopathic Parkinson's disease and ten patients with parkinsonism associated with features suggestive of more extensive involvement of the nervous system, as in the Shy—Drager syndrome. The urodynamic studies revealed detrusor hyperreflexia with reduction of maximal cystometric capacity in only one patient with Parkinson's disease (8%), but in nine patients with parkinsonism associated with other features (90%). Urethral sphincter electromyography did not indicate denervation in any patient of either group. Delayed or incomplete relaxation of the urethral sphincter during micturition was observed in seven patients with Parkinson's disease (58%) and in two patients of the other group (20%). Decreased sweating responses were found in both groups of patients when compared with control subjects. Hypohidrosis was more pronounced in parkinsonism associated with other features than in Parkinson's disease. Differences in sweating between the two sides of the body were observed in both groups of patients. Although there are differences in vesico-urethral and sweating function, they do not precisely differentiate between patients with classical Parkinson's disease and those with parkinsonism associated with features suggestive of more extensive involvement of the nervous system.  相似文献   
44.
45.
One of a novel series of compounds (AMAPS or arylmethylaminopropanediols), 773U82-HCl has shown significant antitumor activity inin vitro and inin vivo tumor systems, but has less animal CNS toxicity than the lead compound in the same series (crisnatol). This study was designed to evaluate the pharmacokinetics, qualitative and quantitative toxicities of 773U82-HCl and to determine the recommended phase II dose (MTD) of 773U82-HCl given as a short infusion daily for 3 days every 3 weeks. Twenty-nine patients with refractory malignancies received 79 courses over 9 dose levels during this study. Doses ranged from 50 to 1060 mg/m2d×3 days. Due to the possibility of local hemolysis with concentrations > 1.5 mg/ml, drug was administered in solutions containing 1.5 mg/ml. Because large volumes were needed at the higher dose levels, the infusion duration was increased from 2 hours to 4 hours. Mild to moderate nausea, vomiting, fatigue, dizziness and headaches were observed. Myelosuppression was the dose limiting toxicity. The recommended phase II dose and schedule was determined to be 800 mg/m2d×3d every 3 weeks. 773U82-HCl plasma concentration-time data were analyzed using a two-compartment pharmacokinetic model. The t1/2 averaged 6 hours and the total body clearance was 75.9 L/hr/m2. The volume of distribution (Vdss) was large, averaging 470 L/m2.Abbreviations ECG electrocardiogram - t1/2 half-life - Vdss volume of distribution - HPLC highperformance liquid chromatography - Vdss steady-state volume of distribution - AUC area under the concentration × time curve - CL total body clearance - Cmax peak plasma level - Vc central volume of distribution  相似文献   
46.
47.
Purpose: The activity of 5-fluorouracil (5-FU) against colon cancer is enhanced by leucovorin and the combination of 5-FU and levamisole has activity in the adjuvant treatment of colonic malignancies. The combination of 5-FU with both leucovorin and levamisole may provide additional benefit in the treatment of colon cancer. Methods: A phase I study to assess qualitative and quantitative toxicities of this three-drug combination and to determine a dose for further phase II testing was undertaken. The role of levamisole as an immunomodulator was also assessed. Results: A group of 38 patients with incurable etastatic malignancies received 119 cycles of treatment at eight dose levels. 5-FU (375 mg/m2 per day) and leucovorin (200 mg/m2 per day) were administered intravenously (days 1–5). Levamisole was administered orally (days 1–3 and 15–17) at doses from 30 to 470 mg/m2 per day. Patients received both 5FU/leucovorin and 5-FU/leucovorin/levamisole in random order for their initial two cycles. All subsequent treatments were with the three-drug combination. Toxicities included nausea, vomiting, stomatitis, thrombocytopenia and granulocytopenia. Diarrhea was the dose-limiting toxicity at 470 mg/m2 per day levamisole. The addition of levamisole resulted in more toxicity than 5-FU and leucovorin alone. No clinical responses were seen with this regimen. The addition of levamisole resulted in more immunomodulation than 5-FU and leucovorin alone as evidenced by release of neopterin from monocytes. Conclusion: With this schedule and dose of 5-FU and leucovorin, the maximum tolerated dose of levamisole was 354 mg/m2. However, given the lack of response and the absence of dose-dependent immunomodulation, this may not be the appropriate dose for further phase 11 studies. Received: 20 October 1995 / Accepted: 16 June 1996  相似文献   
48.
49.
BACKGROUND: Intracranial hemangio-endotheliomas (HE) are rare vascular tumours that present histological features and biological behaviour of an intermediate malignancy. We report the first case of primary HE presenting as multiple intracranial masses. CASE DESCRIPTION: The patient is a 20-year-old female who presented with paresis of the left arm. Magnetic Resonance imaging (MRI) showed multiple lesions in both frontal lobes. Total surgical excision of the tumours was obtained; a histological diagnosis of hemangio-endothelioma was made. Five months later, MRI scan showed new intradiploic skull lesions whereas a scintigraphic study revealed multicentric extracranial bone involvement. Treatment based on interferon-alpha (IFN-alpha) administration was undertaken; this produced partial regression of the lesions. Approximately three years after the first operation, the patient is in good clinical condition. CONCLUSIONS: Surgery continues to play the leading role in the treatment of intracranial HE. However, adjuvant therapy with IFN represents a new and well-tolerated therapeutic method for residual intracranial lesions as well as multicentric extracranial disease.  相似文献   
50.
A number of serum markers have been proposed to improve the sensitivity (and specificity) of the triple test, which, until now, has been the gold standard in second-trimester serum screening for Down's syndrome. Among them, human placental growth hormone (hPGH) has been proposed because of its significantly elevated serum levels in pregnancies affected by chromosomal aneuploidies. Our experience, on maternal serum stored from 32 Down's syndrome-affected pregnancies, confirms a slight but significant increase in hPGH levels compared with controls. These data summarized to that of the previous screening could give a calculated detection rate of 71.9%, better than that of the standard triple test alone (65.6%).  相似文献   
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