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Plasma levels of aspirin and phenylbutazone were estimated before and during administration of low estrogen combination type oral contraceptive for two menstrual cycles in ten and seven female volunteers, respectively. Aspirin was administered at doses of 300 and 600 mg, while phenylbutazone was administered at a dose of 400 mg. Blood samples were collected at intervals of 1, 2, 4, 6, and 8 h for aspirin and 2, 4, 6, 8, 24, 48, 72, and 80 h for phenylbutazone. Plasma levels, plasma half-life (t1/2), as well as area under curve (AUC) for aspirin after use of oral contraceptive revealed lower values. Phenylbutazone levels were not affected. Repeat studies of plasma t1/2 and AUC for aspirin after discontinuation of oral contraceptive showed values similar to basal levels.  相似文献   
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A form of generalized progressive retinal atrophy unlike other previously recorded canine retinal dystrophies has been investigated in Miniature Longhaired Dachshund dogs. Segregation patterns in litters from matings involving affected individuals were consistent with simple autosomal recessive inheritance. The earliest ophthalmoscopic signs, appearing at approximately 6 months of age and coinciding in some cases with the onset of nyctalopia, included changes in the granular appearance of the tapetal fundus followed by generalized tapetal hyper-reflectivity and retinal vascular attenuation; later there was irregular loss of pigment in the non-tapetal fundus and optic atrophy. However, there was marked variation in the age of onset and progression of the disease, even within a single litter. The electroretinogram was normal in waveform and latency in four affected littermates at 10 weeks of age but by 9 months was markedly reduced in amplitude in two pups and virtually extinguished in the others. Significant histological changes at 10.5 weeks of age included thinning of the outer nuclear layer, irregularity and attenuation of the rod photoreceptor outer segments and early disorganization of the rod outer segment disc lamellae. By 25 weeks the photoreceptors were grossly degenerate with short rounded inner segments and only residual amounts of outer segment material remaining. This condition in the Miniature Longhaired Dachshund is later in onset than rod-cone dysplasia in Irish Setters but significantly earlier than progressive retinal atrophy in Tibetan Terriers and progressive rod-cone degeneration in, for example, Miniature Poodles. The condition could therefore serve as a potentially useful model for retinitis pigmentosa in man.  相似文献   
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A common phenomenon in South-East Asia is ageing of the population. This article describes the various stages of development of psychogeriatrics in Hong Kong, Singapore, Malaysia, Thailand, Indonesia and the Philippines. It is only in the last few years that more systematic development of psychogeriatric services has begun under the pressure of an ageing population. The model of service delivery in Hong Kong can serve as an example of development of psychogeriatric services in South-East Asia.  相似文献   
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