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OBJECTIVES: This study aimed to assess the adequacy of safety training provided to young Latino immigrant construction workers. The study posited that, because of their youth and immigrant status, these workers would be less likely to receive adequate training. METHODS: We interviewed 50 youths aged < or =21 who had worked at least 10 days in construction in the previous year. The in-person interview included 140 questions covering a range of construction work and health and safety experiences. RESULTS: Participants reported performing a range of hazardous tasks, some while under the age of 18. Of these, 68% to 72% reported receiving some training, but median training time was only 1 hour. Only 24% reported receiving written training material. Those with less English ability received less training. CONCLUSIONS: Young Latino immigrants in this study received inadequate training given the hazardous work they performed. CLINICAL SIGNIFICANCE: Results of this research, especially the relatively low level of English communication skills among young Latino workers, point to the need for increased bilingual services not just in worker safety training programs, but also in medical clinics and emergency rooms that treat Latino workers.  相似文献   
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BACKGROUND: Double parathyroid adenomas occur in 2% to 15% of primary hyperparathyroidism cases, but the very existence of double adenomas has been controversial. This study was conducted to evaluate the clinical significance and anatomic distribution of parathyroid double adenomas. STUDY DESIGN: Mono-institutional retrospective study of the medical records of 183 unselected consecutive patients who underwent intervention for primary hyperparathyroidism between 1996 and 2003. RESULTS: A total of 14 (7.65%) patients were found to have double parathyroid adenomas. Intraoperative parathyroid hormone (PTH) levels were measured in every case. Two enlarged parathyroid glands were identified in four possible configurations: two both superior, one both inferior, two both right, three both left, two right superior and left inferior, and three left superior and right inferior. There was a preferential crossed bilateral distribution of double adenomas. In all patients, intraoperative PTH levels dropped by at least 50% from baseline after removal of both abnormal parathyroid glands. In this series, no patient developed persistent hypoparathyroidism or had recurrent laryngeal nerve injuries or neck hematoma. All patients remained normocalcemic 9 to 96 months postoperatively. One patient had persistently elevated PTH values with normal serum calcium levels. CONCLUSION: The drop in intraoperative PTH levels and maintenance of normocalcemia postoperatively confirm previous reports that double adenomas do exist and are not simply missed cases of four-gland hyperplasia. There was a preferential crossed bilateral distribution of double adenomas in this series.  相似文献   
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To determine whether lung transfer factor for carbon monoxide (T(L(CO))) alters during menstrual phase and if steroid hormone levels relate to these changes, T(L(CO)) and T(L(CO)) adjusted for both alveolar volume (T(L)/V(A)) and haemoglobin concentration, were measured at five predefined and hormonally confirmed menstrual phases in 13 women. No difference between phases was observed in T(L(CO)) or adjusted values. Moreover, there was no association between the maximal change in oestradiol, progesterone, or oestradiol:progesterone ratio and the change in T(L(CO)) measured at the same time. When the first five chronological measurements, regardless of the menstrual phase at which they were measured, were analysed, T(L(CO)) changed significantly (p<0.05) with a maximal change between the first and fourth test (-2.69+/-2.53, 95% confidence interval). Although these results indicate that the first in a series of T(L(CO)) measurements may be higher, we found neither menstrual cycle phase nor ovarian hormone-related changes in T(L(CO)), and conclude that its adjustment for menstrual phase may not be necessary.  相似文献   
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Checketts  MR; Wildsmith  JAW 《CEACCP》2004,4(2):48-51
The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma.  相似文献   
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A piezoelectric crystal is a unit that changes its frequency in parallel with a change in its mass. This characteristic is exploited in designing flow cell-based immunosensors for detecting the concentration of antibodies in liquid samples. In the present study, computational fluid dynamic techniques are used to optimize the antigen–antibody binding process on an electrode surface placed on the base of a conical flow cell. The geometry optimization of the flow cell was determined to minimize the test time. This time is needed for the electrode to be saturated by the antibody, a process that requires the maximization of the adsorption rate and be accomplished by increasing the shear rate in the vicinity of the electrode. To validate the numerical model and to determine its parameters, experiments were carried out using an identical flow cell. In the experiments, the system did not reach saturation within an acceptable time frame, therefore, the model parameters were determined based on the unsaturated state. The experimental results confirmed the applicability of numerical simulations in predicting the effect of changing the inlet section area of the flow cells, proving the computational model to be very valuable in designing immunosensors based on flow cells. © 2002 Biomedical Engineering Society. PAC2002: 8780-y, 8714Ee, 8710+e, 4711+j  相似文献   
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