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991.
Epidemiological evidence has suggested that consumption of a diet rich in cruciferous vegetables reduces the risk of several types of cancers and chronic degenerative diseases. In particular, broccoli sprouts are a convenient and rich source of the glucosinolate, glucoraphanin, which can release the chemopreventive agent, sulforaphane, an inducer of glutathione S-transferases. Two broccoli sprout-derived beverages, one sulforaphane-rich (SFR) and the other glucoraphanin-rich (GRR), were evaluated for pharmacodynamic action in a crossover clinical trial design. Study participants were recruited from the farming community of He Zuo Township, Qidong, China, previously documented to have a high incidence of hepatocellular carcinoma with concomitant exposures to aflatoxin and more recently characterized with exposures to substantive levels of airborne pollutants. Fifty healthy participants were randomized into two treatment arms. The study protocol was as follows: a 5 days run-in period, a 7 days administration of beverage, a 5 days washout period and a 7 days administration of the opposite beverage. Urinary excretion of the mercapturic acids of acrolein, crotonaldehyde, ethylene oxide and benzene were measured both pre- and postinterventions using liquid chromatography tandem mass spectrometry. Statistically significant increases of 20-50% in the levels of excretion of glutathione-derived conjugates of acrolein, crotonaldehyde and benzene were seen in individuals receiving SFR, GRR or both compared with their preintervention baseline values. No significant differences were seen between the effects of SFR versus GRR. Intervention with broccoli sprouts may enhance detoxication of airborne pollutants and attenuate their associated health risks.  相似文献   
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Osteoporosis is one of the systemic effects associated with chronic obstructive pulmonary disease (COPD). Risk factors for bone loss include smoking, skeletal muscle weakness, low bone mass index (BMI), vitamin D deficiency, glucocorticoid use, hypogonadism and systemic inflammation. The most important clinical feature is vertebral fracture, due to its significant morbidity and mortality. The treatment of osteoporosis includes calcium and vitamin D, bisphosphonates, anabolic agents and pulmonary rehabilitation. Prospective studies are required to determine the prevalence of osteoporosis in COPD and to identify which patients are at high risk for osteoporotic fracture. The development of new drugs to control systemic inflammation may contribute to specific treatments for osteoporosis in COPD.  相似文献   
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Repetitive transcranial magnetic stimulation (rTMS) holds promise as a therapeutic tool in major depression. However, a means to assess the effects of a single rTMS session on mood to guide subsequent sessions would be desirable. The present study examined the effects of a single rTMS session on an affective go/no-go task known to measure emotional-cognitive deficits associated with major depression. Ten patients with an acute episode of unipolar major depression and eight partially or completely remitted (improved) patients underwent 1 Hz rTMS over the left and right dorsolateral prefrontal cortex prior to task performance. TMS over the mesial occipital cortex was used as a control. We observed significantly improved performance in depressed patients following right prefrontal rTMS. This beneficial effect declined with decreasing depression severity and tended to reverse in the improved group. Left prefrontal rTMS had no significant effect in the depressed group, but it resulted in impaired task performance in the improved group. Our findings indicate that the acute response of depressed patients to rTMS varies with the stimulation site and depression severity. Further studies are needed to determine whether the present paradigm could be used to predict antidepressant treatment success or to individualize stimulation parameters according to specific pathology.  相似文献   
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BACKGROUND: Seasonal variations of sexual crime have been seldom studied in the world. Santiago, a city situated at 33 degrees south latitude with a well defined four season climate, has a reliable forensic registry, providing a good opportunity for the assessment of seasonality in this type of crime. MATERIALS AND METHODS: After studying monthly records of sexual abuse from the registry of the Servicio Médico Legal of Santiago between 1990 and 2001, a ratio of observed to expected monthly frequency was obtained, allowing the assessment of the seasonal character of the phenomenon. RESULTS: A total number of 11,844 cases of sexual abuse were recorded during 12 years of the study. Statistically significant differences could be demonstrated between spring and autumn, with a peak in November and a nadir in June. CONCLUSIONS: A distinct seasonal pattern can be set forth for sexual abuse in Santiago, Chile.  相似文献   
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The morphology of Drosophila motor terminals changes along the day with a circadian rhythm controlled by the biological clock. Here, we used electron microscopy to investigate the size, number, and distribution of synaptic vesicles, at intervals of 6 h during 2 consecutive days, under light–dark (LD) or the first 2 days in constant darkness (DD). We found changes in the size and distribution of vesicles located either at the active zone or in the reserve pool, indicating a circadian rhythm of synapse reorganization. Vesicles at the active zone were generally smaller than those in the reserve pool in LD and DD conditions. The size of active zones vesicles decreased twice in LD, corresponding with times of more intense locomotion activity, but only once in DD conditions. Synapse 64:14–19, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
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