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Male mice were exposed to pulsed ultrasound (intensity <1mW, frequency 3.5 MHz) for 30 min or to sham treatment. After30 h, 11, 12 or 13 days, the testes were cytologically and histologicallyexamined (using squash preparations, air-drying and sections).The resulting damage was studied at diakinesis—metaphaseI and II, spermatogonial metaphase and anaphase. The investigationby air-drying did not show any significant increase in chromosomedamage, 30 h, 11, 12 and 13 days after treatment (spermatogonialand spermatocytic metaphases). There was, however, a significantincrease of the frequency of aneuploid cells detected at metaphaseII. Investigations by squash techniques or sections did notreveal adverse effects on the spindles at spermatogonial andspermatocytic anaphases. We suggest that the reduction of fertilitypreviously observed in our clinic could be explained by an increaseof aneuploidy if germ cells are exposed to ultrasound duringdiakinesis of the first meiotic division.  相似文献   
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Schizotypal personality disorder is the prototype of the schizophrenia-related personality disorders and has been demonstrated to have phenomenologic, biologic, treatment, and outcome characteristics similar to those of schizophrenic patients. These studies suggest that patients with schizotypal personality disorder, like schizophrenic patients, show cognitive impairment, but the impairment is more focal and involves primarily working memory, verbal learning, and sustained attention rather than generalized intellectual deficits. Schizotypal patients, like schizophrenic patients show reductions in temporal lobe volume, but seem to be spared the frontal volume reductions found in some studies of schizophrenic patients and in our laboratory. Better frontal “buffering” may prevent the more severe cognitive and social deterioration associated with schizophrenia. Furthermore, schizotypal patients appear to show less susceptibility to psychotic symptoms, in part perhaps because of better buffered subcortical dopaminergic activity as suggested by recent data from a SPECT/amphetamine paradigm, glucose metabolic study, and structural studies of basal ganglia. These findings are discussed in terms of a model of schizotypal personality disorder where schizotypal patients have better capacity for compensatory buffering in lateral and subcortical brain regions, protecting them from the more severe symptoms of chronic schizophrenia.  相似文献   
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Caffeine is the most commonly used psychostimulant throughout the world, with its consumption being especially prevalent among adolescents and young adults, as over 75% of this group consumes caffeine daily. Similarly, the adolescent and young adult age group exhibit the highest incidence of traumatic brain injury (TBI). Given that both caffeine consumption and mild TBI (mTBI) are more prevalent among the late adolescent/young adult age group and that changes in dendritic spine morphology during this developmental period are poorly understood, this study sought to examine the effects of caffeine consumption during late adolescence/early adulthood on recovery from repetitive mTBI (RmTBI). The study specifically focused on changes to neuronal dendritic morphology as synaptic changes likely underlie long-term behavioral outcomes. The results demonstrate that during young adulthood caffeine consumption differentially affects the RmTBI outcomes of males and females, where the effects of caffeine and RmTBI were often additive in males while being equally detrimental, but rarely additive, in females. In general, caffeine and RmTBI induced the greatest impairments in males on cognitive and motor tasks whereas in females the most significant detriments were on pain-related tasks. Both caffeine and RmTBI increased spine density in the Cg3 (medial prefrontal cortex [mPFC]), AID (orbitofrontal cortex [OFC]), and nucleus accumbens (NAc), which is proposed to reflect an impairment in the normal pruning processes. Overall, despite caffeine's neuroprotective abilities among other age groups, this study offers concerning results regarding the detrimental effects of caffeine and RmTBI, in isolation, and especially in combination, in this susceptible population.  相似文献   
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Iron and lipids combine to create oxidative stress, and oxidative stress has a role in the development of cancer. The objective was to determine the risk of cancer among persons who had both elevated iron and lipids. The authors conducted an analysis of the cohort available in the Framingham Offspring Study. Adults aged 30 or more years at baseline had serum iron and high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol, and very low density lipoprotein cholesterol (VLDL-C) assessed in 1979-1982 and were followed for development of cancer until 1996-1997 (n = 3,278). Cox regression models were computed while controlling for age, gender, smoking status, and body mass index. In adjusted models, both elevated iron (hazard ratio (HR) = 1.66, 95% confidence interval (CI): 1.11, 2.46; 29 cases) and VLDL-C (HR = 1.54, 95% CI: 1.04, 2.28; 93 cases) had significant independent risks for development of cancer. When elevated iron was combined with elevated VLDL-C, the adjusted relative risk of cancer increased (HR = 2.68, 95% CI: 1.49, 4.83; 18 cases). Elevated iron and low HDL-C also had a significant adjusted relative risk of cancer (HR = 2.82, 95% CI: 1.50, 5.28; 14 cases). The results suggest that elevated serum iron levels coupled with either high VLDL-C or low HDL-C appear to interact to increase cancer risk in this cohort.  相似文献   
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