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11.

Background  

The ultraviolet properties of textiles dyed with synthetic dyes have been widely reported in literature. However, no study has investigated the ultraviolet properties of natural fabrics dyed with natural colorants. This study reports the Ultraviolet Protection Factor (UPF) of cotton fabrics dyed with colorants of plant and insect origins.  相似文献   
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Firefighting is a stressful and hazardous job. Persons engaged in firefighting are highly exposed to work-related stress as well as to smoke containing a host of chemicals potentially harmful to human health. In order to elucidate whether firefighting affects neuroendocrine and behavioral responses of firefighters, plasma catecholamine (CA) levels and the prevalence of neurobehavioral symptoms in 62 firefighters (all males, mean age 43 yr) and 52 control subjects matched for age and sex were examined in this study. Self-reported neurobehavioral symptoms data were obtained from a questionnaire survey and personal interview. Concentrations of epinephrine (E), norepinephrine (NE) and dopamine (DA) in plasma were measured by high-performance liquid chromatography with electrochemical detection. Compared with matched controls, the firefighters showed higher prevalence (p<0.05) of neurobehavioral symptoms such as burning sensation in the extremities, tingling and numbness, transient loss of memory, and depression, but no significant difference was recorded in the prevalences of anxiety, vertigo and dizziness. The firefighters demonstrated a more than two-fold (p<0.05) rise in plasma levels of E and NE, but the plasma DA level was relatively unchanged. Controlling age and smoking as possible confounders, firefighting was found to be associated with raised E (OR=2.15; 95% CI, 0.98-4.52), and NE levels (OR=2.24 95% CI, 1.22-3.61). In conclusion, the job of firefighting appears to be associated with stimulation of sympathetic activity and a rise in the prevalence of neurobehavioral symptoms.  相似文献   
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Background  

The World Health Organization has declared tuberculosis a global emergency in 1993. It has been estimated that one third of the world population is infected with Mycobacterium tuberculosis, the causative agent of tuberculosis. The emergence of TB/HIV co-infection poses an additional challenge for the control of tuberculosis throughout the world. The World Health Organization is supporting many developing countries to eradicate tuberculosis. It is an agony that one fifth of the tuberculosis patients worldwide are in India. The eradication of tuberculosis is the greatest public health challenge for this developing country. The aim of the present population based study on Mycobacterium tuberculosis is to test a large set of tuberculosis cases for the presence of statistically significant geographical clusters. A spatial scan statistic is used to identify purely spatial and space-time clusters of tuberculosis.  相似文献   
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We evaluated dynamic telecytopathology for on-site-evaluation of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of the pancreas. Realtime images of stained cytology smears were assessed by a cytopathologist while communicating with the on-site operator by telephone. A total of 55 consecutive cases was assessed; preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 69%, 7% and 24%. We also reviewed 55 consecutive cases of EUS-guided FNA of pancreas which had had conventional microscopic on-site evaluation prior to the introduction of telecytopathology. Preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 60%, 9% and 31%. The overall concordance between the preliminary and final diagnosis was 84% for telecytopathology and 87% for conventional microscopy. Neuroendocrine neoplasms and well-differentiated adenocarcinoma were diagnostically challenging for both telecytopathology and conventional microscopy. Telecytopathology was similar in accuracy of preliminary diagnosis to conventional microscopy during EUS-FNA of pancreas.  相似文献   
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Epiphrenic diverticula are outpouchings of the esophagus that retain some or all layers of the esophageal wall. Symptoms such as intermittent dysphagia and vomiting may occur. The authors present a case of an elderly woman with a history of dysphagia who presented with a massive upper gastrointestinal bleed because of a bleeding epiphrenic diverticulum seen at endoscopy who responded to conservative management. Bleeding epiphrenic diverticula should be considered as a cause of upper gastrointestinal bleeding.  相似文献   
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