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11.
D. A. Alexander A. A. Naji S. B. Pinion J. Mollison H. C. Kitchener D. E. Parkin D. R. Abramovich I. T. Russell 《BMJ (Clinical research ed.)》1996,312(7026):280-284
OBJECTIVE: To compare in psychiatric and psychosocial terms the outcome of hysterectomy and endometrial ablation for the treatment of dysfunctional uterine bleeding. DESIGN: Prospective randomised controlled trial. SETTING--Obstetrics and gynaecology department of a large teaching hospital. SUBJECTS: 204 women with dysfunctional bleeding for whom hysterectomy would have been the preferred treatment were recruited over 24 months and randomly allocated to hysterectomy (99 women) or to hysteroscopic surgery (transcervical resection (52 women) or laser ablation (53 women). MAIN OUTCOME MEASURES: Mental state, martial relationship, psychosocial and sexual adjustment in assessments conducted before the operation and one month, six months, and 12 months later. RESULTS: Both treatments significantly reduced the anxiety and depression present before the operation, and there were no differences in mental health between the groups at 12 months. Hysterectomy did not lead to postoperative psychiatric illness. Sexual interest after the operation did not vary with treatment. Overall, 46 out of 185 (25%) women reported a loss sexual interest and 50 out of 185 (27%) reported increased sexual interest. Marital relationships were unaffected by surgery. Personality and duration of dysfunctional uterine bleeding played no significant part in determining outcome. CONCLUSIONS: Hysteroscopic surgery and hysterectomy have a similar effect on psychiatric and psychosocial outcomes. There is no evidence that hysterectomy leads to postoperative psychiatric illness. 相似文献
12.
Comparison of Flowering Time Genes in Brassica Rapa, B. Napus and Arabidopsis Thaliana 总被引:15,自引:0,他引:15
T. C. Osborn C. Kole IAP. Parkin A. G. Sharpe M. Kuiper D. J. Lydiate M. Trick 《Genetics》1997,146(3):1123-1129
The major difference between annual and biennial cultivars of oilseed Brassica napus and B. rapa is conferred by genes controlling vernalization-responsive flowering time. These genes were compared between the species by aligning the map positions of flowering time quantitative trait loci (QTLs) detected in a segregating population of each species. The results suggest that two major QTLs identified in B. rapa correspond to two major QTLs identified in B. napus. Since B. rapa is one of the hypothesized diploid parents of the amphidiploid B. napus, the vernalization requirement of B. napus probably originated from B. rapa. Brassica genes also were compared to flowering time genes in Arabidopsis thaliana by mapping RFLP loci with the same probes in both B. napus and Arabidopsis. The region containing one pair of Brassica QTLs was collinear with the top of chromosome 5 in A. thaliana where flowering time genes FLC, FY and CO are located. The region containing the second pair of QTLs showed fractured collinearity with several regions of the Arabidopsis genome, including the top of chromosome 4 where FRI is located. Thus, these Brassica genes may correspond to two genes (FLC and FRI) that regulate flowering time in the latest flowering ecotypes of Arabidopsis. 相似文献
13.
Effects of glucose and insulin on the activation of lipoprotin lipase and on protein-synthesis in rat adipose tissue. 总被引:4,自引:1,他引:3
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Glucose, and certain sugars that can readily be converted to glucose 6-phosphate, bring about an activation of adipose-tissue lipoprotein lipase when epididymal fat-bodies from starved rats are incubated in the presence of cycloheximide. Other substrates do not support the activation. If the tissue is preincubated in the presence of cycloheximide for longer than 2h, the ability of added glucose to activate the enzyme is lost. On the other hand, the addition of glucose still brings about an increase in lipoprotein lipase activity after preincubation in the absence of cycloheximide for as long as 4h. The magnitude of the increase in enzyme activity brought about by the addition of glucose is increased when protein synthesis is stimulated during the preincubation period by insulin. The results are interpreted in terms of the existence in adipose tissue of a proenzyme pool of lipoprotein lipase that is normally maintained by protein synthesis and that is converted to complete enzyme of higher specific activity by a process that specifically requires glucose. 相似文献
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The effects of light quality (color) on the 14CO2 fixation rates of natural population of photosynthetic sulfur bacteria were tested. The phototrophic bacteria were collected from the sulfide containing waters of 3 stratified lakes. The populations sampled survive in environments where light intensities are very low. Not only are the light intensities low but, due to the light filtering characteristics of the lake water, the light is of specific color. It was determined that the spectral properties of the three lakes differed, hence the quality of light reaching the phototrophic bacteria in each lake differed. It was also observed that only green sulfur bacteria were present in the study lake which transmits mainly red light and both purple and green sulfur bacteria were present in the two study lakes which transmit predominantly green light. Enrichment cultures were set up with phototrophic bacteria from two of the lakes serving as the inocula. Enrichment culture studies and photosynthetic responses of the natural populations indicate that light quality is a major factor in determining the composition of phototrophic bacterial population in some lakes.Non-Common Abbreviations Bchl
Bacteriochlorophyll
- DPM
Disintegrations per minute 相似文献
16.
David Parkin 《American anthropologist》1998,100(2):557-558
Affecting Performance: Meaning, Movement and Experience in Okiek Women's Initiation. Corinne A. Kratz. Washington, DC: Smithsonian Institution Press, 1994. 470 pp. 相似文献
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David T. Parkin 《Bird Study》2013,60(3):223-242
Capsule Based on the 1999 Witherby Memorial Lecture – reviews how developments in molecular and population genetics have led to a reappraisal of species limits in birds. The taxonomy of birds of the West Palearctic has moved from the comparative stability of the ‘Voous List’ into a period of serious activity, with new data emerging in almost every issue of every evolutionary and avian journal! This activity comes from two directions. Firstly, developments in population genetics, molecular biology, acoustics, behaviour and distributional studies have opened new avenues to measuring differentiation among groups of birds. This, in turn, has led to the recognition that earlier views of what constitutes a ‘species’ are in need of modification (‘improvement’), and the emergence of the ‘lineage concept’ of species. I review some of the species concepts most relevant to avian studies, and attempt to show how and why this change has happened, and its consequences for taxonomy and species limits. Examples are given in the form of ‘case studies’, and include Carrion/Hooded Crows Corvus corone/cornix, Green-winged/Eurasian Teals Anas carolinensis/crecca and Phylloscopus warblers. 相似文献
20.
Michelle A. Arya Albert K. Tai Eric C. Wooten Christopher D. Parkin Elena Kudryavtseva Gordon S. Huggins 《PloS one》2013,8(8)
The loss of muscle mass in alcoholic myopathy may reflect alcohol inhibition of myogenic cell differentiation into myotubes. Here, using a high content imaging system we show that ethanol inhibits C2C12 myoblast differentiation by reducing myogenic fusion, creating smaller and less complex myotubes compared with controls. Ethanol administration during C2C12 differentiation reduced MyoD and myogenin expression, and microarray analysis identified ethanol activation of the Notch signaling pathway target genes Hes1 and Hey1. A reporter plasmid regulated by the Hes1 proximal promoter was activated by alcohol treatment in C2C12 cells. Treatment of differentiating C2C12 cells with a gamma secretase inhibitor (GSI) abrogated induction of Hes1. On a morphological level GSI treatment completely rescued myogenic fusion defects and partially restored other myotube parameters in response to alcohol. We conclude that alcohol inhibits C2C12 myoblast differentiation and the inhibition of myogenic fusion is mediated by Notch pathway activation. 相似文献