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Journal of Neurology - The failure of remyelination in multiple sclerosis (MS) contributes to inadequate recovery of neurological function after episodes of active inflammation and demyelination.... 相似文献
65.
About 1-2% of the human genome is allocated to production of receptors for the olfactory epithelium-a hint as to the possible importance of this chemical sense, which includes two anatomically distinct systems: the main olfactory system with sensory cells located in the upper part of the nasal cavity, and the vomero-nasal organ with sensory cells on the nasal septum. In adults, individual odours may influence mate preferences and a growing body of evidence indicates that naturally occurring odours play an important role in the mediation of the infant's behaviour. Even foetal olfactory learning seems to occur and breast odours from the mother exert a pheromone-like effect at the newborn's first attempt to locate the nipple. Newborns are generally responsive to breast odours produced by lactating women. Olfactory recognition may be implicated in the early stages of the mother-infant attachment process, when the newborns learn to recognize the own mother's unique odour signature-a process possibly facilitated by the high norepinephrine release and the arousal of the locus coeruleus at birth. New knowledge about human odour physiology may have diagnostic and therapeutic implications-the initiation and stabilization of breastfeeding and termination of apnoeic spells are mentioned as examples. 相似文献
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ABSTRACT: In-vitro autoradiography was utilized to compare the distribution of 2[125 I]iodomelatonin binding sites or putative melatonin receptors in the gastrointestinal tracts of humans, guinea pigs, mice, rats, hamsters, rabbits, ducks, chickens, pigeons, and quail. In humans, binding was detected in the mucosa of the colon, caecum, appendix, and on their blood vessels but not in the ileum. In the other mammals, significant binding was only demonstrated in the mucosa of the rabbit rectum, mouse colon, mouse rectum, and guinea pig ileum. The distribution of 2[125 I]iodomelatonin binding in the avian gut varied with species. In the esophagus, binding was present in the lamina propria and blood vessels of all four birds. However, only the lamina propria of the chicken and quail proventriculus and ventriculus showed positive binding. For the duodenum and ileum, binding was very strong in the duck lamina propria, weak in the chicken lamina propria, and absent in the quail. In contrast, the pigeon muscle layer was weakly positive. The most striking species difference was found in the caecum where the duck lamina propria showed very strong binding, while the chicken lamina propria was only weakly positive. Conversely, the caecal muscle layer was strongly positive in chicken and quail but negative in duck and pigeon. In the rectum, a similar but less intense pattern of distribution was observed. The tremendous diversity in the distribution of 2[125 I]iodomelatonin binding sites in the gastrointestinal tract is in accord with the hypothesis that melatonin may serve different functions in the gut of different species. 相似文献
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The clinical features of immunoglobulin light-chain (AL) amyloidosis with heart involvement 总被引:9,自引:0,他引:9
Dubrey SW; Cha K; Anderson J; Chamarthi B; Reisinger J; Skinner M; Falk RH 《QJM : monthly journal of the Association of Physicians》1998,91(2):141-157
We reviewed clinical presentation, investigations, therapy, prognosis and
outcome of 232 patients with primary (AL) cardiac amyloidosis. There were
142 men and 90 women. Median age at presentation was 59 years (range
29-85). AL heart disease was unusual both in patients under the age of 40
(3.0%) and in non-Caucasians (6.5%). Fatigue and weakness were the
commonest presenting symptoms. Hallmark features of periorbital ecchymoses
and macroglossia were present in 12.5% and 27.2%, respectively. AL cardiac
amyloidosis was unusual in isolation (3.9%), and most frequently patients
had features of multiorgan dysfunction; heavy proteinuria and features of
malabsorption predominating in this respect. Heart involvement represents
the worst prognostic indicator, with a median survival from diagnosis of
1.08 years, falling to 0.75 years with the onset of heart failure. Current
therapeutic procedures appear to prolong survival, with left ventricular
wall thickness, mass and ejection fraction on echocardiography and late
potentials on signal averaged electrocardiography of use in prognostic
stratification. Cardiac involvement from AL amyloidosis is rapidly fatal.
It should be suspected in all patients with heart failure who have wall
thickening on echo, normal chamber sizes, low EKG voltages and evidence
suggesting a multisystem disease.
相似文献
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Focused US system for MR imaging-guided tumor ablation 总被引:8,自引:0,他引:8
Cline HE; Hynynen K; Watkins RD; Adams WJ; Schenck JF; Ettinger RH; Freund WR; Vetro JP; Jolesz FA 《Radiology》1995,194(3):731