The Cenomanian-Turonian oceanic anoxic event (C/T OAE) is developed in southern Tibet. Organic geochemical study of the Cenomanian-Turonian sediments from the Gamba and Tingri areas shows that the mid-Cretaceous black...The Cenomanian-Turonian oceanic anoxic event (C/T OAE) is developed in southern Tibet. Organic geochemical study of the Cenomanian-Turonian sediments from the Gamba and Tingri areas shows that the mid-Cretaceous black shales in southern Tibet are enriched in organic carbon. The molecular analyses of organic matter indicate marine organic matter was derived from algae and bacteria. In the Gamba area, the organic matter is characterized by abundant tricyclic terpanes and pregane, which are predominant in 191 and 217 mass chromatograms, respectively. Pristane/phytane (Pr/Ph) ratios in the C/T OAE sediments are less than 1, demonstrating the domination of phytane. The presence of carotane can be regarded as a special biomarker indicating oxygen depletion in the C/T OAE sediments in the Tethyan Himalayas. In anoxic sediments, β-carotane and γ-carotane are very abundant. The β- and γ-carotane ratios relative to nC 17 in the Cenomanian-Turonian anoxic sediments vary from 32.28～ 42.87 and 5.10～ 11.01.展开更多
Introduction:Osteoporosis and osteopenia are progressive disorders characterized by decreased bone mass,especially in postmenopausal women.These can be associated with body pain,fractures,hearing loss and balance diso...Introduction:Osteoporosis and osteopenia are progressive disorders characterized by decreased bone mass,especially in postmenopausal women.These can be associated with body pain,fractures,hearing loss and balance disorders.The present study aims to evaluate audio-vestibular function in postmenopausal patients with osteopenia or osteoporosis.Methods:The study included 48 postmenopausal women(new subjects)diagnosed with osteoporosis(n=23)or osteopenia(n=25)in the age range of 50e66 years,as well as 28 normal women as controls.Audiological testing included pure tone audiometry(conventional and extended high-frequency audiometry),speech audiometry,impedance audiometry and otoacoustic emissions,including both transient evoked otoacoustic emissions(TEOAEs)and distortion product otoacoustic emissions(DPOAEs).All subjects also underwent vestibular evoked myogenic potentials testing(both ocular and cervical VEMPs).Results:In the present study,hearing was worse at all frequencies in the osteoporosis group in comparison with the osteopenia and control groups,with worse speech recognition and discrimination scores and OAEs.Vestibular function was affected in 95.65%of women with osteoporosis and 76%of those with osteopenia.Conclusion:Osteoporosis and osteopenia are risk factors for vestibular dysfunction and hearing deficits in postmenopausal women.Thus,hearing and vestibular function should be monitored by audiological and vestibular testing periodically in these individuals.展开更多
文摘The Cenomanian-Turonian oceanic anoxic event (C/T OAE) is developed in southern Tibet. Organic geochemical study of the Cenomanian-Turonian sediments from the Gamba and Tingri areas shows that the mid-Cretaceous black shales in southern Tibet are enriched in organic carbon. The molecular analyses of organic matter indicate marine organic matter was derived from algae and bacteria. In the Gamba area, the organic matter is characterized by abundant tricyclic terpanes and pregane, which are predominant in 191 and 217 mass chromatograms, respectively. Pristane/phytane (Pr/Ph) ratios in the C/T OAE sediments are less than 1, demonstrating the domination of phytane. The presence of carotane can be regarded as a special biomarker indicating oxygen depletion in the C/T OAE sediments in the Tethyan Himalayas. In anoxic sediments, β-carotane and γ-carotane are very abundant. The β- and γ-carotane ratios relative to nC 17 in the Cenomanian-Turonian anoxic sediments vary from 32.28～ 42.87 and 5.10～ 11.01.
文摘Introduction:Osteoporosis and osteopenia are progressive disorders characterized by decreased bone mass,especially in postmenopausal women.These can be associated with body pain,fractures,hearing loss and balance disorders.The present study aims to evaluate audio-vestibular function in postmenopausal patients with osteopenia or osteoporosis.Methods:The study included 48 postmenopausal women(new subjects)diagnosed with osteoporosis(n=23)or osteopenia(n=25)in the age range of 50e66 years,as well as 28 normal women as controls.Audiological testing included pure tone audiometry(conventional and extended high-frequency audiometry),speech audiometry,impedance audiometry and otoacoustic emissions,including both transient evoked otoacoustic emissions(TEOAEs)and distortion product otoacoustic emissions(DPOAEs).All subjects also underwent vestibular evoked myogenic potentials testing(both ocular and cervical VEMPs).Results:In the present study,hearing was worse at all frequencies in the osteoporosis group in comparison with the osteopenia and control groups,with worse speech recognition and discrimination scores and OAEs.Vestibular function was affected in 95.65%of women with osteoporosis and 76%of those with osteopenia.Conclusion:Osteoporosis and osteopenia are risk factors for vestibular dysfunction and hearing deficits in postmenopausal women.Thus,hearing and vestibular function should be monitored by audiological and vestibular testing periodically in these individuals.
