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991.
Muscle-type phosphofructokinase deficiency (PFKD) causes a hemolytic disorder and exertional myopathy in humans and dogs.
In humans, PFKD is accompanied by a disturbed calcium homeostasis and associated adenine nucleotide dysregulation, which may
potentiate the erythroenzymopathy associated with this inherited disorder. This study shows that canine PFKD also manifests
these erythrocyte abnormalities. Compared to normal, healthy red cells, PFK-deficient erythrocytes contain lower concentrations
of ATP and higher concentrations of IMP and calcium, the latter as per a calcium indicator dye. Adenosine monophosphate deaminase
(AMPD) enriched 5000-fold from canine erythrocytes adsorbs to immobilized calcium–calmodulin and the interaction between these
two proteins activates AMPD through a K
mapp effect. This behavior is similar to that of the human erythrocyte enzyme and provides a potential contributing mechanism
for accelerated adenine nucleotide turnover in canine PFKD. We propose that adenine nucleotide replacement strategies could
benefit the erythroenzymopathy in human and canine PFKD and that the dog model of this disorder is an appropriate vehicle
for further elucidating this hypothesis. 相似文献
992.
993.
Richard Cooper Ivan Soltero Jeremiah Stamler Louise Mojonnier Yolanda Hall Dorothy Moss David M. Berkson Tom Tokich 《Journal of the National Medical Association》1982,74(4):349-355
Quit-rates for cigarette smokers in a lifestyle intervention program aimed at reducing coronary risk were 24 percent for all participants and 34 percent for non-dropouts. Recidivism remained very low during participation in the program. Half of the smokers who quit did so after being in the program more than two years. These data suggest that while engaging in an effort to make other changes in lifestyle, many smokers can be helped to quit. Sustained antismoking efforts in the clinical practice of medicine can be expected to share these same positive aspects. While mass public health programs to eliminate smoking and prevent young people from taking up the habit are being developed, health practitioners can make a significant contribution by including vigorous efforts at smoking cessation as part of routine practice. 相似文献
994.
Ramon Sanchez Richard K. Sibley Juan Rosai Ronald F. Dorfman 《Ultrastructural pathology》1981,2(2):101-119
Eleven cases of sinus histiocytosis with massive lymphadenopathy (SHML) involving lymph nodes were studied electron microscopically. Histiocytes were the most conspicuous element of the infiltrate. They could be divided into small and large forms, although transitions were apparent among them. Most of the small histiocytes were located in the medullary cords. The large histiocytes were predominantly seen within sinuses and were subdivided into two types on the basis of their appearance. The most distinctive feature of these histiocytes was the presence of lymphocytes, plasma cells, and neutrophils within their cytoplasm. Other cells present in the infiltrate were lymphocytes, plasma cells, and occasional neutrophils and mast cells. Blood vessels were prominent throughout. Virus particles, bacteria, and Langerhans granules were consistently absent. No morphologic clues were provided by this study as to the etiology of this disorder. 相似文献
995.
996.
Two techniques for measuring palmar sweating were tested for their sensitivity to a standard anticholinergic agent. The finger sweat-print and palmar sweatweight methods were compared in a double-blind, crossover study by determining their relative sensitivity in detecting the antisweating effects of 0.5 mg of atropine sulfate. The sweat-print method was significantly superior in detecting drug-induced sweat reduction and hypothesized sex differences. 相似文献
997.
MAL64
c is a global regulator of α-glucoside fermentation: identification of a new gene involved in melezitose fermentation 总被引:2,自引:0,他引:2
Summary Maltase constitutive mutants at the MAL6 locus have been mapped to the newly identified regulatory gene MAL64
c. We show here that MAL64
c has in addition pleiotropic effects on sugar fermentation: MAL64
c strains constitutively synthesize an -methylglucosidase and can complement a new gene, MTP1, for the fermentation of melezitose and -methylglucoside. MTP1, maps near MAL1, and either encodes a permease which transports melezitose, -methylglucoside, and maltose or regulates the activity of such a permease. This work shows that MAL64
c, a trans-acting regulatory gene, is a global regulatory gene affecting several different pathways of -glucoside metabolism. 相似文献
998.
Antti Hervonen Ilona Linnoila Virginia M. Pickel Pauli Helén Markku Pelto-Huikko Hannu Alho Richard J. Miller 《Neuroscience》1981,6(3):323-330
Both [Leu5]- and [Met5]-enkephalin have been localized immunohistochemically in nerve fibres and in small, intensely fluorescent cells of adult human sympathetic ganglia. The nerve fibres showing enkephalin-like immunoreactivity formed a network varying in density around the sympathetic neurons, some being closely related to the perikarya. No labelled neuronal cell bodies were found. No structures within the ganglion were labelled after reaction with antibodies to vasoactive intestinal polypeptide, adrenocorticotrophin or substance P. No differences between the distributions of [Leu5]-and [Met5]-enkephalin-like immunoreactivities were found.The physiological roles of enkephalins are still unknown, but it is possible that they might act as neurotransmitters or neuromodulators in the human sympathetic nervous system. 相似文献
999.
Opponent appetitive-aversive neural processes underlie predictive learning of pain relief 总被引:2,自引:0,他引:2
Seymour B O'Doherty JP Koltzenburg M Wiech K Frackowiak R Friston K Dolan R 《Nature neuroscience》2005,8(9):1234-1240
Termination of a painful or unpleasant event can be rewarding. However, whether the brain treats relief in a similar way as it treats natural reward is unclear, and the neural processes that underlie its representation as a motivational goal remain poorly understood. We used fMRI (functional magnetic resonance imaging) to investigate how humans learn to generate expectations of pain relief. Using a pavlovian conditioning procedure, we show that subjects experiencing prolonged experimentally induced pain can be conditioned to predict pain relief. This proceeds in a manner consistent with contemporary reward-learning theory (average reward/loss reinforcement learning), reflected by neural activity in the amygdala and midbrain. Furthermore, these reward-like learning signals are mirrored by opposite aversion-like signals in lateral orbitofrontal cortex and anterior cingulate cortex. This dual coding has parallels to 'opponent process' theories in psychology and promotes a formal account of prediction and expectation during pain. 相似文献
1000.
Journal of Muscle Research and Cell Motility - 相似文献