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51.
The present study comprised 1000 child and young workers in small and medium-size industries in Alexandria, as well as 250 control subjects. Almost all young workers work for more than 40 hours/week and suffer from fatigue. Workers' family needs rather than the lack of family care is the responsible factor for sending the child to work, and the economic problems seem to be the underlying factor for all other problems of child labour. Work improves labourers' socio-economic status and smoking habit, and provides a chance for their personal contacts and interactions, which are reflected on their level of intellectual capabilities; however, it has some impact on their food habits affecting their achievement of balanced diet; and no drug addiction exists among all the studied subjects. Noise and dust represent the main occupational exposures (84.4% and 55.8% respectively), followed by exposure to heat (25.3%), vapors and gases (10.4%) and biological materials (9.0%), and nearly 2/3 of the workers have combined exposures. Work injuries occurred to 18.4% of the workers and 7.4% had more than one injury during employment; however, nearly 1/3 of the injuries required absenteeism off work and/or hospitalization. The injuries have been typically related to industrial operations, occurring mostly to hands and fingers (80.4%), and are mainly attributed to lack of training (63.0%). The health services presented to the workers are very poor. The study has been concluded by recommending making the work safe, free from hazards, and ergonomically fit to children, providing educational and training services, covering young workers by social security, and revising legislation of child labour.  相似文献   
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A HPLC assay and solid-phase extraction technique from human plasma has been developed and validated for the novel anticancer agent CT2584, 1-(11-dodecylamino-10-hydroxyundecyl)-3,7-dimethylxanthine, which has recently completed a phase I trial at the Christie Hospital, Manchester under the auspices of the CRC phase I/II committee. Following addition of CT2576, 1-(11-octylamino-10-hydroxylundecyl)-3,7-dimethylxanthine, as internal standard, a solid-phase extraction cartridge (100 mg cyanopropyl) was used to isolate the drug CT2584 from human plasma. Analysis was performed by reversed-phase chromatography. CT2576 was used as internal standard at a concentration of 4 microg ml(-1) for the quantification of CT2584 from plasma for the duration of this work. The lower limit of quantification for the drug CT2584 in buffer using this assay was found to be 0.0122 microM (0.008 microg ml(-1)) and 0.048 microM (0.027 microg ml(-1)) when extracted from human plasma.  相似文献   
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It is known that BK does play a role in the cardioprotective effect of angiotensin converting enzyme (ACE) inhibitors. The present study therefore was conducted to examine the effects of bradykinin (BK) and its antagonist on survival time in spontaneously hypertensive rats (SHR) with coronary artery ligation for 15 min and continuously. We also evaluated the heart rate and blood pressure (BP) in the presence and absence of BK and BK2 receptor antagonist, D-Arg-[Hyp-D-Phe7]BK. Coronary artery was ligated in anaesthetized rats and they were artificially ventilated with room air (stroke volume, 4 ml; 48 strokes/min) as described by the previous investigators. Lead II elecrocardiogram (ECG) was recorded from subcutaneous steel needle electrodes. Results of this investigation indicated that BK treatment 4 microg/kg (i.v.) and 8 microg/kg (i.v.) caused significant (P < 0.05) increase in survival time in SHR with coronary artery ligation for 15 min and continuously as compare to their respective saline-treated controls. However, BK antagonist treatment 4 microg/kg (i.v.) abolished the increase in survival time caused by BK treatment. The mean values of survival time between the saline-treated and BK antagonist plus BK-treated rats did not differ significantly (P > 0.05). The heart rate and BP responses were greatly reduced (P < 0.001) in the presence of coronary artery ligation. These findings suggest that BK might have cardioprotective effect to increase the survival time in rats by activating BK2 receptors after coronary artery ligation.  相似文献   
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With growing evidence of long-term neurological damage in individuals enduring repetitive head trauma, it is critical to detect lower-level damage accumulation for the early diagnosis of injury in at-risk populations. Proton magnetic resonance spectroscopic scans of the dorsolateral prefrontal cortex and primary motor cortex were collected from high school American (gridiron) football athletes, prior to and during their competition seasons. Although no concussions were diagnosed, significant metabolic deviations from baseline and non-collision sport controls were revealed. Overall the findings indicate underlying biochemical changes, consequential to repetitive hits, which have previously gone unnoticed due to a lack of traditional neurological symptoms.  相似文献   
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