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991.
992.
Leukaemia risk in adult populations exposed to environmental air pollution is poorly investigated. We have carried out a population-based case-control study in an area that included a fossil fuel power plant, a coke oven and two big chemical industries. Information on residential history and several risk factors for leukaemia was obtained from 164 cases, diagnosed between 2002 and 2005, and 279 controls. A higher risk for subjects residing in polluted areas was observed, but statistical significance was not reached (adjusted OR = 1.11 and 1.56 for subjects living in moderately and in heavily polluted zones, respectively, p = 0.190). Results suggest a possible aetiological role of residential air pollution from industrial sites on the risk of developing leukaemia in adult populations. However, the proportion of eligible subjects excluded from the study and the lack of any measure of air pollution prevent definitive conclusions from being drawn.  相似文献   
993.
994.
The vasovagal reaction has been widely studied but its anatomic and physiological nature remains uncertain. The mechanisms underlying vasovagal reaction related to blood donation are not completely understood either. Does its occurrence depend on the blood donors' physical characteristics and health variables or psychological factors? On the basis that a psychological approach considerably prevents donor reactions, the effect of fruit juice ingestion was studied in a group of 1849 first-time high-school students as a simple strategy to avoid systemic reactions at blood donation. The reasons for the psychological effect of this hydration protocol are stressed also in light of previous physiological studies on the hemodynamic effects of water or carbohydrate drinks.  相似文献   
995.
A taste component is implicated in the oro-sensory detection of dietary lipids and free fatty acids seem to be involved in fatty food recognition. Bottarga, the salted and semi-dried ovary product of mullet (Mugil spp.), is a rich-fat food. A comparative sensory assessment of different commercial bottarga samples was performed in insect and human models in relation to their lipid composition. The bottarga attractant effect to Ceratitis capitata was assessed by behavioral tests. The subjective odor and taste perception of bottarga samples was investigated in human determining the rate of pleasantness, familiarity, and intensity dimensions using the 7-points Likert-type scale. Bottarga samples showed similar lipid profiles, but differences emerged in total and free fatty acid levels. Significant differences were observed in the attractant effect/acceptability of samples to medflies, negatively correlated to their total and free fatty acids. Insect female exhibited the ability to select among bottarga samples based on their visual and olfactory properties. In the human model, a potential contribution of free fatty acid amount in the pleasantness and familiarity dimensions of taste of bottarga samples was evidenced. Women exhibited a greater ability than men to select bottarga samples based on their better olfactory perception. Our results increase the knowledge about this outstanding product with nutritional and nutraceutical properties.  相似文献   
996.
Traumatic injury to limb peripheral nerves represents an important cause of morbidity and disability. Timely diagnosis and treatment are crucial to optimizing outcomes. The initial evaluation requires a careful history, a thorough physical examination, and electrodiagnostic tests, which lead in most cases to a diagnostic suspicion, but fail to provide an extensive qualitative and quantitative assessment of the nerve damage. Ultrasonography (US) is a low-cost, non-invasive technique which allows for direct visualization of nerve internal structure. It enables performing dynamic examinations and nerves can be followed over long distances in a limb in relatively short times, adding paramount information to extensively characterize the specific type of lesion, and to plan the appropriate treatment. Magnetic resonance imaging (MRI) is complementary to US, especially in examining deep-seated and proximal nerve segments, but is expensive, not available in all institutions and less accepted by patients. The purpose of this review is to describe the role of ultrasonography in the setting of traumatic injury to peripheral nerves, analyzing the main US features in specific types of trauma. Technical aspects with key considerations for optimization are discussed. A brief comparative evaluation between US and MRI is also provided.  相似文献   
997.

We report a case of a double homicide in which the victims, a man and his daughter, were simultaneously killed by a single gunshot. The temperature-based nomogram method for estimation of the time since death was used to ascertain the reliability of the method in a case of simultaneous demise, where the exact time of death was obtained from the analysis of security cameras.

In the case presented, the victims differed for a great number of parameters (e.g., atmospheric conditions, thermal insulation of lower trunk, and, above all, body weight), except for the time of death, that was simultaneous. The correct application of the method permitted us to conclude that the estimated time since death was fully consistent with the circumstantial data obtained by the analysis of security cameras.

No previous papers reporting the use of the nomogram method in a case of ascertained simultaneously death exists in literature; issues concerning the use of the nomogram method have been presented as well.

  相似文献   
998.
Glycogen synthase kinase 3 (GSK-3) is a major kinase implicated in the pathogenesis of Alzheimer’s disease (AD), and reducing its activity may have therapeutic efficacy. Two variants exist, referred to as GSK-3α and GSK-3β. In addition to the latter’s well-described role in the phosphorylation of tau, reports also suggest that GSK-3α may regulate amyloid precursor protein processing and Aβ formation. The activities of both GSK-3α and GSK-3β are reduced by lithium, a well-tolerated drug used in humans to combat bipolar disorder. Here, we investigate the therapeutic efficacy of chronic lithium administration in aged 3xTg-AD mice that harbor both plaques and tangles. We found that lithium reduced tau phosphorylation but did not significantly alter the Aβ load. Despite the reduction in phosphotau, lithium treatment did not improve deficits in working memory. Although other studies have investigated the effects of lithium on tau biochemistry, this study represents the first to address comprehensively its therapeutic potential on other critical aspects of AD including its effect on Aβ and learning and memory. It remains to be determined from human clinical trials whether lithium treatment alone will improve the clinical outcome in AD patients. These results, however, suggest that the most efficacious treatment will be combining lithium with other anti-Aβ interventions.  相似文献   
999.
The antiangiogenic, antitumoural and antimetastatic effects of two novel sulphonic derivatives of distamycin A, PNU145156E and PNU153429, were studied in a Kaposi’s sarcoma-like tumour model obtained by injecting nude mice with cells releasing extracellular HIV-Tat protein, derived from a tumour which developed in a BK virus/tat transgenic mouse. Both PNU145156E and PNU153429 were administered intraperitoneally every fourth day for three weeks at doses of 100 or 50 mg/kg of body weight respectively, starting one day after injecting the tumour cells. Both drugs delayed tumour growth in nude mice, preventing neovascularization induced by the Tat protein. PNU153429 also significantly reduced the number and size of spontaneous tumour metastases. Both effects on tumour growth and metastases were augmented by treating simultaneously nude mice with 7.5 mg/kg of body weight of minocycline given per os daily for four weeks starting four days after injecting the tumour cells. Neither acute nor chronic toxic side-effects were observed during the life span of treated nude mice. Due to their antiangiogenic and anti-Tat effects, these drugs are promising for the treatment of Kaposi’s sarcoma in AIDS patients. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
1000.
Several authors have advanced the hypothesis that the right cerebral hemisphere predominates during REM sleep. This hypothesis was tested by giving a newly-devised unilateral tactile recognition test to 16 right-handed male subjects during waking and upon awakenings from REM and NREM sleep. A two-way analysis of variance revealed both a main effect for hand (the left hand being superior to the right) and a condition (waking-REM-NREM) X hand interaction. Consistent with the hypothesis of right-hemisphere activation during REM, left-hand superiority upon awakenings from REM was greater than that during waking; in the NREM condition, no between-hand difference was observed. The latter result, as well as previous findings by Gordon, Frooman, and Lavie (1982), seems to point to the presence of left-hemisphere activation during NREM and, more generally, to the link between hemispheric functional alternation and the REM-NREM cycle.  相似文献   
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