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61.
Data are presented from a prospective clinical replication series of ten consecutive high-medication headache patients who presented for nondrug treatment of their headaches. For the first eight, an attempt was made to withdraw the patients from medication, with the assistance of relaxation training, prior to entering a comprehensive self-regulatory treatment program. For the last two, drug withdrawal accompanied the treatment. Six of the ten patients showed clinically significant reductions in headache activity, which held up over follow-ups of up to 12 months. Psychological tests provide some discrimination between success and failures.This research was supported in part by a grant from NINDS, No. NS-23340. Appreciation is expressed to Dr. Kenneth A. Appelbaum and Ms. Denise Michultka for their roles in this study.  相似文献   
62.
Summary The single and combined actions of transforming growth factor (TGF)-beta and osteogenin were evaluated with regard to induction of colony formation and reexpression of the differentiated phenotype by dedifferentiated rabbit articular chondrocytes in soft agarose under serum-free conditions. TGF-beta alone did not promote colony formation and induced accumulation of proteoglycans and type II collagen at significantly lower levels than those induced by osteogenin. Although synergism between these two growth factors occurred with respect to the induction of colony formation, their joint action on reexpression of the differentiated phenotype was additive. Complex interactions between the two growth factors may explain the latter phenomenon.  相似文献   
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Rate determination of protein synthesis utilizing tracer amino acid incorporation requires accurate assessment of the specific radioactivity of the labeled precursor aminoacyl-tRNA pool. Previously published methods presumably useful for the measurement of any aminoacyl-tRNA were unsuccessful when applied to [35S]methionine, due to the unique chemical properties of this amino acid. Herein we describe modifications of these methods necessary for the measurement of 35S-aminoacyl-tRNA specific radioactivity from small tissue samples incubated in the presence of [35S]methionine. The use of [35S]methionine of high specific radioactivity enables analysis of the methionyl-tRNA from less than 100 mg of tissue. Conditions for optimal recovery of 35S-labeled dansyl-amino acid derivatives are presented and possible applications of this method are discussed.  相似文献   
66.
Of the physical parameters tested for in vitro baculovirus infection, multiplicity of infection was most important in governing percent cell infection. Most plaques formed within the first 5 min of incubation. Efficiency of infection, however, was low, and the virus titer did not diminish during prolonged incubation. Efficiency of infection improved markedly when cells or virus were preincubated with selected polyanions and polycations. Precise regulation of the pH, osmotic pressure, and ionic composition of the cell culture medium also promoted maximum in vivo infection.  相似文献   
67.
Eleven patients with episodic cluster headache were assessed and offered a treatment program consisting of 8 weeks of training in abbreviated progressive relaxation followed by 12 sessions of thermal biofeedback. Four dropped out before treatment began. Of the seven who completed the full treatment regimen, three (27% of initial sample) reported some degree of improvement when their next cluster bout occurred. In no one was the disorder eliminated.This research was supported by a grant from the National Institute of Neurological and Communicative Disorders and Stroke, NS-15235.  相似文献   
68.
J. Sikora 《Protoplasma》1981,109(1-2):57-77
Summary Certain species ofParamecium demonstrate rotational cytoplasmic streaming, in which most cytoplasmic particles and organelles flow along permanent route, in a constant direction. By means of novel methods of immobilization, observation and recording, some dynamic properties of cytoplasmic streaming have been described. It was found that the velocity profiles of coaxial layers of cytoplasm have a (parabolic) paraboidal shape and the mean output of cytoplasm flow in different examined zones of streaming is constant. As the consequence of randomly distributed elementary propulsion units within the cytoplasm, particles, which serve as markers of movement, exhibit movements of a saltatory nature; this form of movement is seen inParamecium streaming only in cases of error due to polarization of the saltating particles. Interaction of actin filaments and myosin is likely to occur under specific conditions in microcompartments of cytoplasm where local solations are generated eventually leading to contractions which might propagate on gelated neighbouring areas. Places of elementary contractions are scattered. Therefore the motile effect appears as streaming. Rotational cytoplasmic streaming inParamecium may serve as a convenient model for the study of the dynamics and function of cytoplasmic motility.  相似文献   
69.
A previous paper described a kinetic model for electrogenic sodium-potassium transport in cardiac muscle, combining a thermodynamically-constrained transport model with simple passive permeabilities for sodium and potassium to generate a cardiac action potential (Chapman, Kootsey & Johnson, 1979). The present paper explores the extent to which this simplest of active-passive transport models can account (without further modification) for the electrophysiological behavior of cardiac muscle. The long term (several minutes) changes in the duration of the action potential observed following a change in stimulation rate are predicted by the model through a shift in the steady-state current-voltage relationship caused by small changes in inside ion concentrations. The diastolic hyperpolarization observed following an increase in rate is also predicted, including the linear relationship between the maximum diastolic depolarization and the rate of stimulation. Varying the outside potassium concentration in the model produces changes in the rest potential and current-voltage relationship similar to published data. Deviations from ideal potassium electrode behavior occur at both high and low concentrations because of effects on the pump. The model not only predicts the observed shift of the current-voltage curve in the depolarizing direction with increasing [K+]0, but also the crossing of the curve in normal [K +]0 without having to assume a variation in gK. Anoxia was introduced into the model by changing the concentrations of ATP and ADP, thereby enabling the model to account for the rapid diastolic depolarization observed in myocardial ischemia.  相似文献   
70.
Many patients in Britain with chronic renal failure suitable for renal replacement treatment die because not enough treatment facilities are available. Moreover, the number of renal transplants performed is insufficient to meet even present needs, so the number of patients on dialysis is rising. The integrated dialysis and transplant unit in Aberdeen, which has a population base much smaller than the average British unit, meets community needs for dialysis and transplantation. The problem of harvesting cadaver kidneys has been solved; the present supply has not only enabled the number of patients on dialysis to remain stable but has resulted in a net export of kidneys. The Aberdeen unit shows how estimated needs for chronic dialysis and renal transplantation may be met.  相似文献   
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