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101.
102.
The objectives of this study are to determine the prevalence of hand-arm vibration syndrome (HAVS) and the characteristics of the vibrotactile perception threshold (VPT) among users of hand-held vibrating tools working in a tropical environment. A cross sectional study was done among 47 shipyard workers using instruments and a questionnaire to determine HAVS related symptoms. The vibration acceleration magnitude was determined using a Human Vibration Meter (Maestro). A P8 Pallesthesiometer (EMSON-MAT, Poland) was used to determine the VPT of index and little finger at frequencies of 31.5 Hz and 125 Hz. The mean reference threshold shift was determined from the reference threshold shift derived from the VPT value. The results show a moderate prevalence of HAVS (49%) among the shipyard workers. They were exposed to the same high intensity level of HAVS (mean = 4.19 ± 1.94 m/s(2)) from the use of vibrating hand-held tools. The VPT values were found to be higher for both fingers and both frequencies (index, 31.5 Hz = 110.91 ± 7.36 dB, 125 Hz = 117.0 ± 10.25 dB; little, 31.5 Hz = 110.70 ± 6.75 dB, 125 Hz = 117.71 ± 10.25 dB) compared to the normal healthy population with a mean threshold shift of between 9.20 to 10.61 decibels. The frequency of 31.5 Hz had a higher percentage of positive mean reference threshold shift (index finger=93.6%, little finger=100%) compared to 125 Hz (index finger=85.1%, little finger=78.7%). In conclusion, the prevalence of HAVS was lower than those working in a cold environment; however, all workers had a higher mean VPT value compared to the normal population with all those reported as having HAVS showing a positive mean reference threshold shift of VPT value.  相似文献   
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104.
The purpose of the present study was to test endothelial function and to determine if plasma homocysteine levels are associated with endothelial injury in patients with Behcet's disease (BD). Flow-mediated dilation in patients with BD was smaller than that of control subjects (p = 0.001), and mean plasma homocysteine levels in patients with BD were significantly higher (p = 0.0001). On regression analysis, only mean plasma homocysteine concentration was independently related to flow-mediated dilation (F = 5.7, p = 0.001).  相似文献   
105.
This study is aiming to investigate the association between walking and depression, anxiety and stress among adults from Jazan, Saudi Arabia. This study was a cross-sectional investigation where data was collected via an online self-administered questionnaire. The questionnaire had 4 components that measured demographics of the sample, presence of depression, anxiety and stress, and walking history. Differences in median scores of depression, anxiety, and stress according to the measured characteristics were tested via the Mann–Whitney U test. Multivariable logistic regression was performed to estimate odds of reporting depression, anxiety, and stress according to the measured characteristics. A total of 472 adult subjects participated in the current study. The median age of the participants was 23 years, and 52% were males. Half of the participants had variable degrees of depression and anxiety while 39% of the participants had variable degrees of stress. Gender appeared to have the strongest influence on level of depression, anxiety, and stress among the recruited sample (odds ratio 1.8, 2.1, 1.6 respectively (P values < .01). Upon stratifying the sample according to gender, marital status seems to have an association with depression, anxiety, and stress among females (P values < .05). Among males, only walking more than 3 days was associated with the reduction of anxiety (P value .005) and depression (P value .06). This study identified gender difference where walking was not associated with mental health among women but relatively associated among males.  相似文献   
106.
Ti-15%Zr alloy and Ti-15%Zr-2%Ta alloy were fabricated to be used in biomedical applications. The corrosion of these two alloys after being immersed in simulated body fluid for 1 h and 72 h was investigated. Different electrochemical methods, including polarization, impedance, and chronoamperometric current with time at 400 mV were employed. Also, the surface morphology and the compositions of its formed film were reported by the use of scanning electron microscope and energy dispersive X-ray. Based on the collected results, the presence of 2%Ta in the Ti-Zr alloy passivated its corrosion by minimizing its corrosion rate. The polarization curves revealed that adding Ta within the alloy increases the corrosion resistance as was confirmed by the impedance spectroscopy and current time data. The change of current versus time proved that the addition of Ta reduces the absolute current even at high anodic potential, 400 mV. The results of both electrochemical and spectroscopic methods indicated that pitting corrosion does not occur for both Ti-Zr and Ti-Zr-Ta alloys, even after their immersion in SBF solutions for 72 h.  相似文献   
107.
Purpose: To evaluate the relationship between glaucoma and Helicobacter pylori (H. pylori) infection. Participants: 137 patients with primary open angle glaucoma (POAG), 85 control subjects and 250 patients with gastric symptoms participated Methods: The presence of H. pylori infection in glaucoma patients, and glaucoma incidence in H. pylori infected patients  相似文献   
108.
109.
We report the case of a 41-yr-old male with chronic hepatitis C who developed severe thrombocytopenia on interferon alfa-n3 therapy. The patient was enrolled in a multi-center trial of interferon alfa-n3 in the treatment of chronic hepatitis C. In the 10th wk of therapy, he presented with gingival bleeding and a petechial rash. Complete blood count demonstrated WBC 5,800/mm3, Hgb 16.3 g/dl, Hcl 45.5%, and platelet count 6,000/mm3. Interferon was withdrawn, and he was admitted to intensive care and was treated with platelet transfusion, intravenous steroids, and intravenous immunoglobulin. His platelet counts returned to 157,000/mm3 in 7 days and remained normal on a tapering dose of prednisone. Bone marrow biopsy/aspirate demonstrated numerous megakaryocytes. Stored plasma was negative for development of specific high-titer anti-platelet antibody. We suggest that the clinical findings and response to therapy are consistent with interferon-induced idiopathic throm-bocytopenic purpura.  相似文献   
110.
IOP variation     
Erdurmus M  Aydin B  Yagci R  Karadag R  Keskin U 《Ophthalmology》2006,113(7):1253; author reply 1254-4; author reply 1254
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