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131.
Osteoarthritis (OA) is the most common joint disorder, associated with loss of articular cartilage, osteophyte formation, subchodral bone change, synovitis and characterized by chronic and often disabling pain and stiffness of one or more joints. The pathogenesis of the disease is complex and still debated, even if recent studies have shown that reactive oxygen species may participate in the initiation and progression of OA. Moreover, it is known that pulsed electromagnetic fields are useful in the OA treatment, owing to their analgesic and anti-inflammatory properties. This work evaluated lipid peroxidation, glutathione, and ascorbic acid levels in patients with OA of spine, before and after the application of a new electromagnetic system, the TAMMEF (Therapeutic Application of a Musically Modulated Electromagnetic Field) system. In TAMMEF system, the extremely low frequencies electromagnetic field is piloted by a musical signal and its parameters (frequency, intensity, waveform) are modified in time, randomly varying within the respective ranges: so all possible codes can occur during a single application. Twenty patients affected by OA of spine and 20 healthy subjects were enrolled in this study. Plasma levels of ascorbic acid (AA), glutathione (GSH) and malondialdehyde (MDA) (as index of lipid peroxidation) were determined in patients and controls, before the beginning of treatment (first day of therapy) and at the end of cycle. All patients underwent a cycle of 10 daily sessions of 30 min each. Our study showed a significant increase of MDA level and a significant decrease of both AA and GSH levels in patients with OA compared to control group. These findings support the role of oxidative stress in the pathogenesis of OA. After TAMMEF treatment in the OA group, analysis revealed a significant decrease in plasma MDA and AA levels (P < 0.05 and P < 0.01, respectively), no significant difference in GSH levels. Reduction in MDA level could be due to the decreased generation of reactive oxygen species and/or to the increased detoxification activity mediated by GSH. No significant difference in GSH levels, evidenced in OA patients after TAMMEF treatment, could be due to effect sparing of AA on GSH. Furthermore, a beneficial symptomatic effect was observed in all patients.  相似文献   
132.
Organophosphorus and organochlorine pesticides, phosphorated plasticizers, chloroparaffins and phthalate esters contamination in bergamot essential oils produced in Calabria in the crop years 1999-2000 was studied by HRGC in connection with detectors FPD, ECD, MS. Residues of dicofol and tetradifon were found in oils from both crop years. The mean dicofol concentration was 0.26 mg/l in samples from 1999 and 0.20 mg/l in those from 2000; the mean tetradifon content was 0.06 mg/l for both the crop years. Among plasticizers, residues of diisobutyl phthalate, di-n-butyl phthalate, and bis(2-ethylhexyl) phthalate were found in samples from crop years 1999 and 2000, the mean content were 1.22 and 1.23 mg/l, 1.51 and 1.65 mg/l, 1.38 and 1.42 mg/l respectively.  相似文献   
133.
The accumulation ability of the major elements sulphur, nitrogen and carbon by the moss Sphagnum capillifolium (Ehrh.) Hedw. and the lichen Pseudevernia furfuracea (L.) Zopf exposed in bags in Naples urban area,was investigated. Bags were exposed at the beginning of July 1999 and gathered in two subsequent moments: at the end of the dry season (after 10 weeks of exposure) and during the wet season (after 17 weeks of exposure), to include the effects of rainy conditions. Sulphur and N content of the lichen increased all over the exposure period, while the level of C did not change significantly either after 10 or 17 weeks of exposition. For the moss the S accumulation was limited to the dry period of exposure, whereas N and C content decreased with exposure. Results, in contrast with those obtained in a previous study on trace elements bioaccumulation [Adamo et al., Environmental Pollution, (2003) 122, 91-103], suggest that accumulation of gaseous pollutants is strongly influenced by biomonitor vitality and that lichen bags are a more reliable and effective tool for monitoring S, N and C atmospheric depositions in urban areas compared to moss bags, because of greater lichen resistance to dry and stressing conditions of urban environment.  相似文献   
134.
The detection of very rare variants in prenatal diagnosis often causes counseling difficulties and anxiety in parents. We describe a duplication of the proximal region of chromosome 9 short arm in two cases of prenatal diagnosis and in one young woman, with evidence that such rearrangement is an uncommon variant. The duplication was investigated using Fluorescence in situ hybridization (FISH). Although the cytogenetic findings were indicative of a ‘duplication 9p syndrome’ associated with mental and developmental retardation, we were able to demonstrate that the rearrangement was a heteromorphism with no phenotypic consequence. We also determined the breakpoint regions of the rearrangement and identified the BAC probes that precisely define the duplicated region devoid of risk of phenotypic effects. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
135.
Abstract: For most wastewater discharges to streams, the effluent creates a plume that becomes less distinct as it mixes with the receiving water. Constant‐discharge tracer studies were used to characterize the plume or physical mixing zone (PMZ) at two similar transition terrain streams. At both sites, the laterally unmixed PMZs did not extend across the entire stream and mixing occurred relatively quickly. The observed plumes were significantly smaller than the regulatory mixing zone (RMZ) allowed by the State of Colorado. At Site 1 mixing occurred within a much shorter distance due to the presence of a riffle zone located a few meters downstream of the discharge point. Interpretation of field data with an analytical model suggests that the effective transverse dispersion coefficient (kz) for the riffle zone at Site 1 (~1 m2/s) was significantly higher than the average value over the longer nonriffle section at Site 2 (~0.01 m2/s). These results imply that to achieve the fastest mixing in transition terrain streams, thereby minimizing the size of the PMZ, discharge outfalls should be located upstream and close to riffle zones.  相似文献   
136.
Noroviruses are recognized as the leading cause of human acute viral gastroenteritis worldwide. The rate of outbreaks on cruise ships has grown significantly in recent years. Given the potentially harmful consequences of outbreaks for passengers and crewmembers and the subsequently high costs for cruise companies, disease outbreaks on cruise ships represent a serious public health issue. The aim of our study was to systematically review published studies related to Norovirus outbreaks on commercial cruise ships. We searched the PubMed and Scopus scientific databases. We included eligible studies published from January 1990 to July 2013 that were written in English and described infectious episodes involving at least two passengers and/or crewmembers on a commercial cruise ship. As a result, 15 studies and seven reviews met the inclusion criteria, describing a total of 127 outbreaks. The majority of the cases were reported in Europe and the USA, affecting <1 to 74 % of the embarked passengers. In the majority of the studies, stool samples and/or serum specimens from ill passengers were collected and tested for laboratory confirmation. Twelve studies reported that an ad-hoc questionnaire was administered. Fifteen studies investigated the possible source of infection which was contaminated food in the majority of cases. Our findings suggest a strong need for the monitoring and implementation of preventive measures in semi-closed communities, such as cruise ships. It would be advisable to strengthen all relevant initiatives in order to improve the detection of, response to and control of Norovirus outbreaks on cruise ships.  相似文献   
137.
Selective predation can be an important force driving the evolution of organisms. In particular, sex-biased predation is expected to have implications for sexual selection, sex allocation and population dynamics. In this study, we analysed sex differences in the predation of the western green lizard (Lacerta bilineata) by the Eurasian kestrel (Falco tinnunculus) during the reproductive season. In addition, we investigated whether the rate of predation differed during the 8-year study period and among the three habitats studied. We collected lizard remains from nest boxes of kestrels. Freshly killed lizards were sexed by visual inspection, whilst the sex of head remains was assigned by analysing the cephalic scale morphology using geometric morphometrics. Our results show that the risk of being predated by a kestrel in our population was overall about 3.55 times higher for males than for females. To our knowledge this is the first study showing a male-biased predation in a lizard species. The selective predation of males was consistent between years over the 8-year study period (1999-2006) and also consistent between the three types of kestrel hunting habitat. Overall predation rates on lizards differed between habitats, depending on the year. We propose that the observed sex-biased predation is mainly due to sex differences in lizard behaviour.  相似文献   
138.
Environmental Science and Pollution Research - The surface coating present on a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan,...  相似文献   
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