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The subject of enlarged legs is vast and complex. Up to now there has been no organic classification of the clinical picture involved. The basic problem is that of the criterion on which to base the classification. Literature on this subject has opted for the pathogenic criterion because it seems to facilitate the formulation of a classification which is of use to the doctor. One possibility would be to divide the syndrome into vascular and non-vascular swollen legs. The first group could in turn be separated into macro-circulating and micro-circulatory. The micro-circulatory forms can be primitive or secondary. Amongst the secondary micro-circulatory forms, two other groups can be singled out: secondary forms with local cause and secondary forms caused by organic pathology. However, there are clinical forms which are on the periphery of these different groups and these forms are subject to discussion regarding nosographic localization. 相似文献
994.
A case of Bonnet syndrome associated with blindness due to bilateral eye disease and a posterior parasagittal meningioma is reported. It is assumed that visual afferent deprivation alone is not enough to produce the syndrome and that, in most instances, a 'cerebral factor' must be operative if hallucinoses are to occur. The distinction between hallucinosis and hallucinations is favored and a common neural circuit for the mediation of hallucinotic imageries in general is suggested. One should not immediately put the blame on obvious eye or visual pathways affections when facing cases of Bonnet syndrome, as they are not likely to explain the complex array of images perceived by any given patient. On the contrary, the possibility of a clinically covert intracranial disease should be always raised and intensively looked for. 相似文献
995.
Dawn and dusk simulation as a therapeutic intervention 总被引:1,自引:0,他引:1
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This study compares the heart sizes and left ventricular masses of soldiers (n = 11) with age- and body size-matched groups of sedentary men (n = 10) and accomplished athletes (n = 11). Echocardiography revealed that active duty soldiers (A) who met minimal fitness standards and pentathletes (P) had greater average left ventricular (LV) end-diastolic volumes (A = 10%, NS; P = 28%, p less than 0.05), stroke volumes (A = 29%, NS; P = 44%, p less than 0.01), and LV masses (A = 22%, NS; P = 76%, p less than 0.01) than sedentary subjects. Athletes had an average LV wall thickness which was 23% (p less than 0.05) greater than that of soldiers and 32% (p less than 0.01) greater than that of sedentary men. The LV wall thickness to radius ratio (h/r) was similar between soldiers and sedentary men, but in athletes the h/r was greater (p less than 0.01) than in the less conditioned subjects. These data suggest that soldiers who meet minimal standards of fitness exhibit cardiac morphometric features consistent with endurance conditioning. However, the soldiers studied were significantly less (p less than 0.001) conditioned than the competitive athletes. These data suggest that improvements in aerobic and cardiac conditioning could be achieved through a greater emphasis on physical training. 相似文献
999.
S. Tsagarakis Feng Ge L. H. Rees G. M. Besser A. Grossman 《Journal of neuroendocrinology》1989,1(2):129-133
While extensive evidence suggests that adrenoceptors play an important role in the control of growth hormone in the rat, there are few studies involving the direct measurement of growth hormone-releasing hormone (GHRH). We have therefore developed a radioimmunoassay for rat GHRH, and used it to investigate the modulation of GHRH release by noradrenaline from incubated rat hypothalamus in vitro. The GHRH radioimmunoassay had no significant cross-reactivity with other hypothalamic or GHRH-related peptides, and was sensitive to 4 pg/tube; intra- and interassay coefficients of variation were 6% and 12% respectively. Single incubated rat hypothalami produced a stable and readily measurable output of GHRH in successive 20 min incubations after an initial 60 min preincubation; the release of GHRH was increased in the presence of 56 mM KCI, but did not respond to KCI-depolarization when calcium was excluded from the medium. Stimulated GHRH release was identical to synthetic rat GHRH(1–43) on high-performance liquid chromatography and Sephadex G-75 chromatography.
Noradrenaline stimulated GHRH secretion in a dose-dependent manner in the concentration range 10−10 — 10−6 M, with a plateau in response at 10−7 M. Stimulation with noradrenaline 10−7 M was blocked by idazoxan 10−5 M and attenuated by thymoxamine 10−5 M, but was unaffected by timolol 10−5 M. Both the α2 -adrenoceptor agonist guanfacine, and the α1 -adrenoceptor agonist methoxamine, specifically stimulated GHRH secretion.
It is concluded that noradrenaline stimulates the release of GHRH at both α1 and α2 -adrenoceptors. 相似文献
Noradrenaline stimulated GHRH secretion in a dose-dependent manner in the concentration range 10
It is concluded that noradrenaline stimulates the release of GHRH at both α
1000.