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101.
Ciliated hepatic foregut cysts are a rare entity usually found in adults. We present a case of a 3-year-old boy incidentally noted to have a radiographically complex liver cyst on computed tomographic scan. Given the complex appearance, the cyst was excised. Pathology revealed a ciliated hepatic foregut cyst. This is the second child and youngest patient affected with this lesion reported in the literature. The etiology of the lesion and an argument for surgical removal in pediatric patients are presented.  相似文献   
102.
Bone mineral density (BMD) may be associated with hearing loss in older adults. Demineralization of the cochlear capsule has been associated with hearing loss in those with Pagets disease of the bone and otosclerosis. Osteoporosis may also result in cochlear capsule demineralization. We hypothesized that lower hip BMD and lower heel ultrasound measurements would be associated with hearing loss in a population-based sample of 2,089 older black and white men and women. Bone parameters and hearing function were measured at the fourth clinical follow-up visit. Audiometric threshold testing was used to measure air- and bone-conduction hearing sensitivity. BMD of the hip and its subregions was measured using dual-energy X-ray absorptiometry. Calcaneal bone measurements [broadband ultrasound attenuation (BUA), speed of sound (SOS) and the quantitative ultrasound index (QUI)] were obtained using heel ultrasound. After adjusting for known hearing loss risk factors, no association was found between hearing and any of the bone measurements in whites and black women. In black men, however, lower hip BMD was associated with higher odds of hearing loss; for each standard deviation decrease in total hip BMD, the odds of hearing loss were 1.41 (95% confidence interval 1.08, 1.83), 1.39 (95% CI 1.07, 1.82) for femoral neck BMD and 1.65 (95% CI 1.26, 2.16) for trochanter BMD. Conductive hearing loss was associated with lower heel ultrasound measurements, though only among white men. The results of this study are mixed and inconclusive. Lower BMD of the hip and its subregions was associated with hearing loss among black men, but not among whites or black women. Lower measurements on heel ultrasound were associated with conductive hearing loss, though only among white men. These results suggest that axial and appendicular bone parameters may be modestly associated with hearing loss in older men, but not in women.  相似文献   
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A NICE fallacy     
A response is given to the claim by Claxton and Culyer, who stated that the policies of the National Institute for Health and Clinical Excellence (NICE) do not evaluate patients rather than treatments. The argument is made that the use of values such as quality of life and life-years is ethically dubious when used to choose which patients ought to receive treatments in the National Health Service (NHS).  相似文献   
106.
Loss of peripheral right-ear advantage in age-related hearing loss   总被引:1,自引:0,他引:1  
In young adults with normal hearing, the right ear is more sensitive than the left to simple sounds (peripheral right-ear advantage) and to processing complex sounds such as speech (central right-ear advantage). In the present investigation, the effects of hearing loss and aging on this auditory asymmetry were examined at both peripheral and central levels. Audiograms and transient evoked otoacoustic emission (TEOAE) and distortion product otoacoustic emission amplitudes were used to assess cochlear function. The contralateral suppression of TEOAEs was measured to assess the medial olivocochlear efferent system. The Hearing in Noise Test (HINT; binaural speech) was conducted to assess higher central auditory function. A group of aged subjects with normal hearing (flat audiograms) were compared to a group of aged subjects with sloping audiograms (presbycusis). At the cochlear (peripheral) level, the normal hearing group showed significantly higher otoacoustic emission amplitudes for the right ear compared to the left ear, which is consistent with the right-ear dominance normally seen in young adults. However, this finding was reversed in the presbycusic group that showed higher left-ear emission amplitudes. At the brainstem level, the amplitudes of TEOAE contralateral suppression were small and no significant difference was found between the right and left ears in both groups. On the contrary, HINT results showed a continuous dominance of the right ear (left hemisphere) in both groups, which was consistent with previous reports showing that the right hemisphere is more affected by age than the left hemisphere.  相似文献   
107.
Plectin and human genetic disorders of the skin and muscle   总被引:8,自引:0,他引:8  
Abstract Recent progress in understanding the molecular organization of the cutaneous basement membrane zone (BMZ) has revealed an intricate network of structural proteins necessary for stable association of the epidermis to the underlying dermis. Molecular genetics of the cutaneous BMZ has also revealed that defects in as many as nine distinct genes within the dermal-epidermal junction which result in different forms of epidermolysis bullosa (EB). a group of heritable mechano-bullous disorders. We have recently demonstrated that a variant of EB associated with late-onset development of muscular dystrophy (EB-MD. MIM no. 226670) results from mutations in the gene encoding plectin (PLEC1). a cytoskeleton associated attachment protein present in the hemidesmosomal inner plaque and the sarcolemma of the muscle. Consequently, mutations in this multi-functional gene/protein system can result in phenotypic manifestations of EB-MD both in the skin and the muscle. In this overview, we will summarize the domain organization of plectin and the structure of the corresponding gene (PLEC1). as well as the genetic basis of EB-MD in families studied thus far. Elucidation of the molecular basis of this subtype of EB adds to our understanding of the structural and functional complexity of the cutaneous BMZ.  相似文献   
108.
A novel connexin 30 mutation in Clouston syndrome   总被引:6,自引:0,他引:6  
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