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The shear modulus of the vocal fold is an essential parameter required to enhance our understanding of how the vocal fold operates, to develop mathematical models of phonatation, and to provide benchmarks to quantify the effectiveness of surgical procedures. The authors announced the successful deployment of an instrument to measure vocal fold elasticity in vivo last year, and now present the data taken from eight patients in vivo. The shear modulus was measured at the mid-membranous point, in a transverse direction with respect to the axis drawn between the anterior commissure and vocal process. The range of mean shear modulus results is 701–2,225 Pa, with a mean value of 1,371 Pa.  相似文献   
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In a prospective cohort study of the long-term sequelae of induced abortion, a comparison is made between a group of 6418 women who had an induced abortion (cases) and a control group of 8059 women recruited with an unplanned pregnancy which was not terminated with an induced abortion (controls). The present paper reports on 729 cases and 1754 controls who had a post-recruitment pregnancy. In general, prior induced abortion had no material effect on the rate of pregnancy-related morbidity, nor on the rate of congenital abnormalities and neonatal death in the offspring. There was, however, a significant difference in two specific conditions. In the post-index pregnancy in the cases there was an increased relative risk (RR 2.26) of the occurrence of urinary tract infection and a decreased risk (RR 0.25) of pregnancy-related anaemia.  相似文献   
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Clinical observations have suggested that estrogens are involved in the pathogenesis of postmenopausal osteoarthritis (OA). However, positive and negative associations between the incidence of OA and serum estrogen concentrations have been reported. In contrast to this, osteoporosis is regarded as a disease with a strong estrogen-dependent component. Moreover, there is an interaction between estrogen and calcium deficiency: calcium supplementation potentiates the effect of estrogen therapy. The present study was designed to investigate how estrogen deficiency affects the articular cartilage depending on calcium supply. The distribution of different types of glycosaminoglycans and collagens can be used as an indicator for extracellular matrix changes induced by estrogen deficiency. Different levels of dietary calcium were therefore fed to intact and ovariectomized G?ttingen miniature pigs for one year before articular cartilage was harvested. The histochemical staining for heavy sulfated glycosaminoglycans in the extracellular matrix of ovariectomized miniature pigs, especially of those fed with a low calcium diet, was stronger in comparison to intact animals. In intact animals type II-collagen was immunodetected in all zones of unmineralized and mineralized articular cartilage, while immunostaining for this protein was negative to weak in the deep radiated fiber zone of ovariectomized minipigs. These results suggest that the synthesis of heavy sulfated glycosaminoglycans and immunohistochemically detectable type II-collagen is possibly influenced by estrogen deficiency. In conclusion, under estrogen deficiency, the extracellular matrix of articular cartilage underwent similar changes to those observed in physiologically aging cartilage where keratan sulfate is increased as a heavy sulfated glycosaminoglycan.  相似文献   
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Cutaneous T-cell lymphoma   总被引:1,自引:0,他引:1  
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