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R.T. Gun 《Australian and New Zealand journal of public health》1988,12(2):161-166
Aging and noise are the two main causes of hearing loss. To estimate the extent to which hearing loss is due to noise and is therefore preventable, an analysis was undertaken, using U.S. surveillance data, of the prevalence of hearing loss in workers in industries categorised according to the percentages of the workforce exposed to noise levels of 85 dBA or more. It was estimated that 13 per cent of the U.S. workforce was exposed to these noise levels, and that occupational noise exposure accounted for 20 per cent of self-reported hearing loss in the male workforce. Applying the industry-specific exposures to Australia, it is estimated that some 657,000 workers are exposed to noise levels of 85 dBA or more in this country. Australian Bureau of Statistics data indicate that constant noise accounts for 38 per cent of self-reported hearing loss in Australian adult males (although this figure would include hearing loss due to non-occupational noise). Data from both countries indicate that the prevalence of noise-induced hearing loss in females is negligible. 相似文献
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The effects of the two enantiomers of 3-PPP upon alpha 1-adrenergic and muscarinic receptors coupled to the inositol phospholipid (PI) breakdown response have been investigated. 3-PPP(-) and 3-PPP(+) were found to antagonize the noradrenaline (10 microM)-stimulated PI breakdown in rat cerebral cortical miniprisms with IC50 values of 18 and 61 microM, respectively. The dopamine receptor antagonists haloperidol and raclopride were also antagonists, with IC50 values of 0.4 and 25 microM, respectively. 3-PPP(-) and raclopride were found further to act as competitive antagonists, with pA2 values of 6.03 and 5.44, respectively. 3-PPP(-), 3-PPP(+) and haloperidol also antagonized the muscarinic receptor-mediated carbachol (50 microM)-stimulated PI breakdown in cortical miniprisms, albeit at high concentrations (IC50 values of 91, 170 and 28 microM, respectively) whereas raclopride produced only 24% inhibition at the highest concentration tested (100 microM). 相似文献
5.
Ten (E)-and (Z)-isomers of 2-phenylcyclopropylamine (PCA), 1-Me-PCA, 2-Me-PCA, N-Me-PCA, and N, N-diMe-PCA and fifteeno
−, m−, p− isomers of (E)-PCA with substituents of Me, Cl, F, OMe, OH were synthesized in this laboratory and tested for the inhibition of rat brain
mitochondrial MAO-A and MAO-B. The effects of substituents, their positions, and stereochemistry on the inhibition were assessed
for the compounds with substituents at cyclopropyl and amino groups and QSAR analyses were performed using the potency data
of ring-substituted compounds. The best correlated QSAR equations are as follows: pI50=0.804 Π2 Blo−1.069 Blm+0.334 Lp−1.709 HDp+7.897 (r=0.945, s=0.211, F=16.691, p=0.000) for the inhibition of MAO-A; pI50=1.815 π-0.825 Π2 R+0.900 Es2+0.869 Es3+0.796 Es4−0.992 HDp+0.562 HAo+3.893 (r=0.982, s=0.178, F=23.351, p=0.000) for the inhibition of MAO-B. Based on the potency difference
between stereoisomers of cyclopropylamine-modified compounds and on QSAR results, it is proposed that the active sites of
MAO-A are composed of one deep hydrophobic cavity near para position, two hydrophobic cavities interacting with Me group,
a hydrophobic area accomodating phenyl and cyclopropyl backbone, steric boundaries, a hydrogen-acceptor site near para position,
and an amino group binding site and that in addition to the same two hydrophobic cavities, hydrophobic area, steric boundaries,
hydrogen-acceptor site, and amino group binding site, another steric boundary near para position and a hydrogen donating site
near ortho position constitute active sites of MAO-B. 相似文献
6.
Ana Cecília Montes Gil Raquel Lorenzetti Gun Bergsten Mendes André Moreno Morcillo Adyléia Aparecida Dalbo Contrera Toro Marcos Tadeu Nolasco da Silva Maria Marluce dos Santos Vilela 《Revista paulista de medicina》2007,125(4):205-209
CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated. 相似文献
7.
测定110例肝病的抗凝血酶Ⅲ(AT-Ⅲ)活性,62例低于正常(56.4%),均值为60.1±38.2%。50例正常对照为100.0±26.7%。重症肝炎、慢性活动性肝炎及失代偿期肝硬化活性显著下降,均值分别为12.9±13.0%、51.0±34.6%、43.3±29.6%.AT-Ⅲ活性在评价肝脏功能方面较凝血酶原时间敏感,具有一定的实用意义。 相似文献
8.
Postural responses to lateral perturbation in healthy subjects and ankle sprain patients. 总被引:4,自引:0,他引:4
D Brunt J C Andersen B Huntsman L B Reinhert A C Thorell J C Sterling 《Medicine and science in sports and exercise》1992,24(2):171-176
The purpose of this study was to investigate postural responses of healthy subjects and patients with recent ankle sprains following a perturbation that created sway in the frontal plane. EMG data were taken from the posterior tibialis (PT) (not monitored in patients), peroneal longus (PL), and tibialis anterior muscles (TA). Subjects stood on a platform that provided a rotational perturbation (approximately 70 degrees.s-1) in the frontal plane. This perturbation had the effect of everting and loading one limb while inverting and unloading the contralateral limb. An initial response in the PT of the loaded limb and the PL of the unloaded limb was noted at approximately 50 ms following the perturbation. This was followed by a bilateral response in the TA at 60 ms. The amplitude of the TA muscle was significantly greater in the loaded limb. For ankle sprain patients a bilateral TA response and a PL response in the unloaded limb was noted at approximately 65 ms. TA response amplitude ratios between the loaded and unloaded limbs were similar to that of the healthy subjects. These data suggest that ankle sprain patients use a modified postural response following lateral perturbation as a compensation for the injury. 相似文献
9.
Jovan P Antovic Marianne Yngen Claes-G?ran G Ostenson Aleksandra Antovic H?kan N Wallen Gun Jornesk?g Margareta Blomb?ck 《Blood coagulation & fibrinolysis》2003,14(6):551-556
We investigated thrombin activatable fibrinolysis inhibitor (TAFI) and its influence on fibrinolysis by measuring pro-TAFI activity and total TAFI antigen in 38 patients with type I diabetes mellitus (18 with and 20 without microvascular complications), as well as in 20 healthy controls. The pro-TAFI levels in the two groups of patients did not differ from those in the control group. Total TAFI antigen [i.e. pro-TAFI, TAFI and inactive carboxypeptidase U (TAFIi)] tended to decrease in both the patient groups (59.7 +/- 7.2 and 73.4 +/- 8.9% with and without microvascular complications, respectively) compared with controls (91.9 +/- 12.2%) (P = 0.12). We also assessed the overall hemostatic potential (OHP) in plasma, the clot lysis time and the overall fibrinolytic potential. The OHP was significantly higher in patients with complications compared with controls (8.9 +/- 0.9 versus 6.7 +/- 0.4; P < 0.05) and also higher in the diabetics without complications (7.8 +/- 0.6), although the latter difference did not reach statistical significance. Levels of clot lysis time and overall fibrinolytic potential were similar in the two groups of patients and the controls. The increased OHP in plasma from diabetic patients with microvascular complications indicates an imbalance of the hemostatic system towards a prothrombotic state. No signs of impaired fibrinolysis were observed in patients with diabetes. Using the OHP method for estimation of overall hemostasis, it seems that TAFI does not influence either fibrinolysis or the increased thrombotic potential observed in patients with type I diabetes mellitus. 相似文献
10.
目的 探讨和评估选择性靶动脉栓塞骶骨肿瘤后对外科切除肿瘤的价值和方法。方法 运用Seldinger技术,对9例骶骨肿瘤患者进行肿瘤供血动脉及肿瘤内血管全部彻底栓塞,栓塞材料应用明胶海绵,栓塞后1周内行手术切除术。结果 彻底的术前栓塞手术中失血量明显减少,9例骶骨肿瘤均得到彻底切除,平均失血量为1090ml。术后平均随访15个月,未见肿瘤局部复发。结论 骶骨肿瘤切除术前选择性靶动脉栓塞可有效减少术中出血,有利于肿瘤的彻底切除,为顺利切除骶骨肿瘤提供了有价值的方法。 相似文献