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91.
92.
Lack of islet amyloid polypeptide regulation of insulin biosynthesis or secretion in normal rat islets 总被引:4,自引:0,他引:4
We examined the effects of rat islet amyloid polypeptide (IAPP) on insulin biosynthesis and secretion by isolated rat islets of Langerhans. Culture of islets for 24 h in the presence of 10(-6) M IAPP and 5.5 mM glucose had no effect on insulin mRNA levels. Similarly, the rates of proinsulin biosynthesis were not altered in islets incubated in 10(-4)-10(-9) M IAPP and 5.5 mM glucose, nor was the rate of conversion of proinsulin to insulin changed at 10(-6) M IAPP. Addition of 10(-5) M IAPP to islets incubated in 11 mM glucose decreased the fractional insulin secretion rate; however, the secretion of newly synthesized proinsulin and insulin was not affected. These data indicate that it is unlikely that IAPP is a physiologically relevant modulator of insulin biosynthesis or secretion. 相似文献
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94.
Career Satisfaction and Clinician-Educators: The Rewards and Challenges of Teaching 总被引:1,自引:1,他引:0
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Allen D. Roses Margaret A. Pericak-Vance Ann M. Saunders Donald Schmechel Dmitry Goldgaber Warren Strittmatter 《Epilepsia》1994,35(S1):S20-S28
Summary: Strategies used in molecular genetics have changed modern neurology. The gene or genes responsible for several major neurologic diseases have now been identified using "reverse" or positional genetics. Unexpected new genetic mechanisms have been discovered in human neurologic diseases, including (a) identical mutations of the prion protein gene in Creutzfeldt-Jakob disease and fatal familial insomnia with the phenotypic expression directed by an accompanying polymorphism; (b) stable duplications of chromosome 17 in Charcot-Marie-Tooth disease (type 1 A) that involve many genes, only one of which appears to cause neuropathy; and (c) highly variable, dynamic mutations in myotonic dystrophy, fragile X syndrome, and Kennedy's syndrome that modulate variable expressivity in multiple tissues. There is growing recognition that neurologic diseases are often complex genetic diseases with multifactorial rather than simple modes of inheritance. For example, genetic association/linkage strategies have interacted with biochemistry and immunopathology studies to produce new insights into the disease mechanism of late-onset Alzheimer's disease. The role of apolipoprotein E in late-onset Alzheimer's disease is an example of how new analytical techniques of genetic disease can be applied to dissect multiple genes. Similar research strategies are suggested for the study of epilepsy as a complex disease. 相似文献
97.
Rachel Yehuda Ann Steiner Boaz Kahana Karen Binder-Brynes Steven M. Southwick Shelly Zemelman Earl L. Giller 《Journal of traumatic stress》1997,10(1):93-100
Alexithymia was measured in non-treatment seeking, community-dwelling Holocaust survivors using the Toronto Alexithymia Scale—Twenty Item Version (TAS-20). Scores of survivors with (n = 30) and without (n = 26) posttraumatic stress disorder (PTSD) were compared, and associations among alexithymia, severity of trauma, and severity of PTSD symptoms were determined. Survivors with PTSD had significantly higher scores on the TAS-20 compared to survivors without PTSD. TAS-20 scores were significantly associated with severity of PTSD symptoms, but not with severity of trauma. This study adds to our knowledge of the relationship between alexithymia and trauma by demonstrating that this characteristic is related to the presence of posttraumatic symptoms and not simply exposure to trauma. 相似文献
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Ann Bowling Morag Farquhar Emily Grundy Juliet Formby 《International journal of geriatric psychiatry》1992,7(5):307-321
This article reports findings from a longitudinal survey of very elderly people living at home in London. The research aimed to identify social, psychological and physical characteristics associated with positive ageing and successful survival in the community in later life and its converse—negative ageing—as well as the associated policy implications. Associations with psychiatric morbidity, measured using the General Health Questionnaire, among sample members without cognitive impairment between the baseline interviews in 1987 and at follow-up, two and a half years later in 1990, are reported. Twenty-five per cent of survivors scored over the threshold of the GHQ in 1987 and 30% scored over the threshold in 1990. Half of those with a score over the threshold in 1990 also scored over the threshold in 1987. Hierarchical regression (using residualized change analysis) was used to estimate the effects of the independent variables on changes in psychiatric morbidity. The most significant predictor of psychiatric morbidity (GHQ score) in 1990 was baseline GHQ score, followed by health and functional status scores. Health and functional status were also the strongest predictors of baseline (1987) GHQ scores. The uniqueness of the study lies in the collection of follow-up data on a sample of very elderly people, given that most surveys are corss-sectional and contain too few people aged 85+ to merit separate analysis. It contributes to the small body of literature on outcome of depression. The lack of consistent associations with recovery from psychiatric morbidity in the literature enhances the importance of studies aiming to identify factors associated with different outcomes. 相似文献
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