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351.
There have been reports in the media and claims in the courts that radiofrequency (RF) emissions from mobile phones are a cause of cancer, and there have been numerous public objections to the siting of mobile phone base antennas because of a fear of cancer. This review summarizes the current state of evidence concerning whether the RF energy used for wireless communication might be carcinogenic. Relevant studies were identified by searching MedLine with a combination of exposure and endpoint terms. This was supplemented by a review of the over 1700 citations assembled by the Institute of Electrical and Electronics Engineers (IEEE) International Committee on Electromagnetic Safety as part of their updating of the IEEE C95.1 RF energy safety guidelines. Where there were multiple studies, preference was given to recent reports, to positive reports of effects and to attempts to confirm such positive reports. Biophysical considerations indicate that there is little theoretical basis for anticipating that RF energy would have significant biological effects at the power levels used by modern mobile phones and their base station antennas. The epidemiological evidence for a causal association between cancer and RF energy is weak and limited. Animal studies have provided no consistent evidence that exposure to RF energy at non-thermal intensities causes or promotes cancer. Extensive in vitro studies have found no consistent evidence of genotoxic potential, but in vitro studies assessing the epigenetic potential of RF energy are limited. Overall, a weight-of-evidence evaluation shows that the current evidence for a causal association between cancer and exposure to RF energy is weak and unconvincing. However, the existing epidemiology is limited and the possibility of epigenetic effects has not been thoroughly evaluated, so that additional research in those areas will be required for a more thorough assessment of the possibility of a causal connection between cancer and the RF energy from mobile telecommunications.  相似文献   
352.

Background

Stress fracture is the single most common cause for the lost number of manpower days during training. The conventional treatment options begin with rest and cessation of precipitating activity. However the demands of military training provide little tolerance for prolonged periods of rest. In the recent past ultrasound therapy (UST) has been reported to speed up healing of stress fractures.

Methods

In the present study, a total of 67 cases of stress fracture were studied for the effect of ultrasound therapy on healing time. Study protocol used was double blind placebo controlled.

Result

Study results showed that the mean number of days of incapacitation was 25.46 days in the ultrasound treatment group as compared to 39.92 in the placebo group, a difference of 14 days, which was statistically highly significant.

Conclusion

The results of the study convincingly prove that ultrasound treatment is effective in cases of stress fracture.Key Words: Stress fracture, Ultrasound therapy  相似文献   
353.
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355.

Background

The Mental Health Inventory (MHI-5) and the Mental Health Component Summary score (MCS) derived from the Short Form 36 (SF-36) instrument are well validated and reliable scales. A drawback of their construction is that neither has a clinically validated cutpoint to define a case of common mental disorder (CMD). This paper aims to produce cutpoints for the MHI-5 and MCS by comparison with the General Health Questionnaire (GHQ-12).

Methods

Data were analysed from wave 9 of the British Household Panel Survey (2000), providing a sample size of 14,669 individuals. Receiver Operating Characteristic (ROC) curves were used to compare the scales and define cutpoints for the MHI-5 and MCS, using the following optimisation criteria: the Youden Index, the point closest to (0,1) on the ROC curve, minimising the misclassification rate, the minimax method, and prevalence matching.

Results

For the MHI-5, the Youden Index and the (0,1) methods both gave a cutpoint of 76, minimising the misclassification rate gave a cutpoint of 60 and the minimax method and prevalence matching gave a cutpoint of 68. For the MCS, the Youden Index and the (0,1) methods gave cutpoints of 51.7 and 52.1 respectively, minimising the error rate gave a cutpoint of 44.8 and both the minimax method and prevalence matching gave a cutpoint of 48.9. The correlation between the MHI-5 and the MCS was 0.88.

Conclusion

The Youden Index and (0,1) methods are most suitable for determining a cutpoint for the MHI-5, since they are least dependent on population prevalence. The choice of method is dependent on the intended application. The MHI-5 performs remarkably well against the longer MCS.  相似文献   
356.
Primary or nonobstructive, endogenous lipoid pneumonia is a rare clinical entity usually associated with an underlying systemic disease. The present report describes a case involving a 21-year-old man with systemic-onset juvenile rheumatoid arthritis who developed primary endogenous lipoid pneumonia. Multiple treatment regimens were attempted; however, definitive management was only achieved through double-lung transplantation.  相似文献   
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