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81.
The study examined the flow of a state mental health agency's case-managed clients into its forensic mental health court clinic systems for evaluation of competency to stand trial (CST) for a criminal offense. An analysis of merged encounter data from the case management and court clinic systems revealed that roughly 2% of the case-managed population were referred to court clinics for evaluation of CST during a 1-year period, but that these 2% represented roughly one eighth of that year's court clinic evaluees. The likelihood of this involvement was higher for males, African-Americans, and Latinos, and for persons with a history of substance abuse, and also was associated with higher levels of previous hospitalization. In addition, CST evaluees were more likely to be non-White, male, and uninsured than were case-managed evaluees. These data indicate that demographic characteristics, substance abuse, and lack of insurance are potential risk factors for forensic and, by inference, criminal justice system involvement among persons with mental illness. 相似文献
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Antioxidant supplementation decreases lipid peroxidation biomarker F(2)-isoprostanes in plasma of smokers. 总被引:5,自引:0,他引:5
Marion Dietrich Gladys Block Mark Hudes Jason D Morrow Edward P Norkus Maret G Traber Carroll E Cross Lester Packer 《Cancer epidemiology, biomarkers & prevention》2002,11(1):7-13
Free radicals in cigarette smoke (CS) cause oxidative damage to proteins, DNA, and lipids, contributing to the pathobiology of atherosclerosis, heart disease, and cancer. In vitro studies have shown that antioxidants quench free radicals and ameliorate certain aspects of biomolecular damage caused by CS. It is hypothesized that a combination of antioxidants is more effective than a single antioxidant, due to their interactions. To investigate whether supplemental antioxidants reduce CS-related lipid peroxidation in vivo and whether they are more effective in combination, we conducted an intervention study in smokers. In a randomized double-blind placebo-controlled trial, we investigated whether vitamin C or an antioxidant mixture containing vitamin C, alpha-lipoic acid, and vitamin E decreases plasma F(2)-isoprostane levels, an index of oxidant stress, in smokers. Plasma of 126 smokers (mean age, 46 years; age range, 20-78 years) was analyzed for F(2)-isoprostanes at baseline and after intervention with antioxidants and placebo. In smokers with a body mass index (BMI) above the median, 2 months of daily supplementation with 500 mg of vitamin C decreased plasma F(2)-isoprostane levels by 28.8 pmol/liter when compared with the placebo group (P = 0.001); levels in the mixture group were 7.45 pmol/liter lower after treatment, but this difference was not statistically significant (P = 0.14). There was no treatment effect in smokers with a low BMI. BMI was significantly positively associated with plasma F(2)-isoprostane levels (trend P = 0.001). Antioxidants decrease smoking-related lipid peroxidation markers of oxidative stress in humans with high BMI. Our results do not indicate that an antioxidant combination is more effective than vitamin C alone. The intake of antioxidants may help prevent smoking-related diseases. Smoking cessation should still be considered the most effective way to prevent smoking-related diseases. 相似文献
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The free radical scavenging activities and inhibitory effect of lipid peroxidation of a delphinidin derivative in eggplant were investigated. Delphinidin-3-(p-coumaroylrutinoside)-5-glucoside (nasunin), an anthocyanin, was isolated as purple colored crystals from eggplant peels. Using electron spin resonance spectrometry and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), hydroxyl radicals (OH) or superoxide anion radicals (O(2)(-)) generated by the Fenton reaction or the hypoxanthine-xanthine oxidase system were measured as DMPO-OH or DMPO-OOH spin adducts. L-Ascorbic acid 2-[3, 4-dihydro-2,5,7,8-tetramethyl-2-(4,8, 12-trimethyltridecyl)-2H-1-benzopyran-6yl-hydrogen phosphate] potassium salt (EPC-K1) and bovine erythrocyte superoxide dismutase (SOD) were used as standards for OH and O(2)(-) scavengers, respectively. Nasunin showed potent O(2)(-) scavenging (143+/-8 SOD-equivalent U/mg) and OH scavenging (0. 65+/-0.07 EPC-K1-equivalent micromol/mg) activities. Then, by changing the concentration of DMPO to vary the trapping rate of OH, the presence of a competitive reaction between nasunin and OH was studied. The 50% inhibition dose (ID(50)) obtained from the inhibition curve did not change, indicating OH scavenging of nasunin is not due to direct scavenging but inhibition of OH generating system by chelating ferrous ion. Nasunin protection against H(2)O(2)-induced lipid peroxidation in rat brain homogenate was measured at 586 nm using the indicator of malonaldehyde and 4-hydroxyalkenals. Nasunin (<50 microM) protected against lipid peroxidation of brain homogenates. The findings suggest that nasunin is a potent O(2)(-) scavenger and has protective activity against lipid peroxidation. 相似文献
86.
Intracranial germ cell tumors are a heterogeneous group of lesions which occur in children and adults. Within the classification of intracranial germ cell tumors, there are a variety of different tumor types which carry different prognoses. The diagnosis of an intracranial germ cell tumor usually requires histological information, but a subgroup of tumors will secrete specific tumor markers, including alpha-fetoprotein and beta-human chorionic gonadotropin, which may obviate the need for surgical intervention. The management of intracranial germ cell tumors in both children and adults remains unsettled. Germinomas have a good prognosis, as over 90% of patients can be effectively treated with radiation therapy. The dose and volume of radiation therapy needed for disease control is not well established, and controversy exists concerning the need for whole brain or craniospinal radiation therapy for localized tumors. Germinomas are also chemosensitive and recent reports suggest that the dose and volume of radiation therapy required for disease control can be lessened with the addition of adjuvant chemotherapy. The outcome for patients with nongerminomatous germ cell tumors is less favorable. Radiation therapy alone will result in disease control in 40%-60% of patients. The addition of chemotherapy to radiation therapy may improve the rate of survival. 相似文献
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J H Edwards R A Hyman S J Vacirca M A Boxer S Packer I H Kaufman H L Stein 《AJR. American journal of roentgenology》1985,144(5):1015-1020
Magnetic resonance (MR) imaging of the orbit was performed with a 0.6 T superconducting imaging system in 100 patients with normal orbits who were being evaluated for brain pathology and in 21 additional patients with a variety of orbital lesions to determine the efficacy of MR imaging in displaying orbital abnormalities. Usually, MR studies were performed using a multislice technique with multiple spin-echo pulse sequences and 30, 60, and 90 msec echo times and 500, 1500, and 2000 msec repetition times. Using section thicknesses of about 8 mm, imaging was performed in the transaxial, coronal, and sagittal projections. Pixel size was 0.9 X 1.8 mm, and the examination took about 30 min. The MR findings were compared with computed tomographic (CT) findings in all cases. Either combined axial and coronal studies of 5-mm-thick sections or a thin axial study of 1-mm-thick sections followed by reformatting techniques to obtain multiplanar images was used. Contrast enhancement was used in the CT studies. Both MR and CT clearly demonstrated the soft-tissue abnormality in all cases except two, in which MR failed to detect the abnormality. In one, MR failed to detect a small retrobulbar hemorrhage that occurred after a surgical procedure for retinal detachment. In the second case, rather extensive calcification in the posterior choroidal layers and lens was not detected by MR imaging. In several other cases, MR provided information beyond that obtained with CT. MR has the advantage of providing exquisite anatomic detail in multiplanar images, and it appears to be more sensitive than CT in detecting small, subacute and chronic hemorrhage within soft-tissue masses in the orbit and in detecting ischemia of the globe. CT is superior to MR imaging in portraying fine bone detail. 相似文献