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886.
Roger H. L. Wilson Seymour M. Farber Janet E. Collins 《The Western journal of medicine》1957,87(3):161-165
A series of patients with chronic respiratory insufficiency were treated with intermittent positive pressure breathing, which was combined with administration of bronchodilator drugs of the epinephrine series. Spirographs were made before and after treatment. The series included patients with chronic bronchitis and emphysema, fibrosis of various kinds, senile emphysema and bronchogenic carcinoma.Although the majority showed objective improvement, a significant proportion in all groups did not, and some were made worse, apparently on a basis of check valve mechanisms unresolved by the bronchodilator drug. In cases in which the method benefited the patient, the benefit was greater than that obtained with bronchodilator drugs alone. 相似文献
887.
Laura Ponticorvo Norma Greenfield Adele Wolfson Fred Chasalow Seymour Lieberman 《Archives of biochemistry and biophysics》1980,200(1):223-231
The steroid 21-hydroxylase activity present in the microsomes of bovine adrenals is stimulated by components of the cytosol. The nature of these activators has been examined by two procedures. The first consisted of treating cytosol with increasing amounts of acetone. When the concentration of the organic solvent reached 50%, a precipitate, presumably proteinaceous, formed. The portion of the precipitate that was redissolvable in 0.05 m potassium phosphate buffer, pH 7.2, contained 7–15% of the stimulatory activity originally present in the cytosol. When the acetone concentration was raised to 90%, another active material precipitated. It was identified as oxidized glutathione (GSSG) and it accounted for about 5% of the activity in the cytosol. In an attempt to avoid the harmful effects of acetone, the second procedure employed only gel filtration and ion exchange resin chromatography. By these means the cytosol was separated into 11 protein fractions and a small molecular weight material. Forty six percent of the proteins and the same fraction of the stimulatory activity present in the original cytosol were recovered. Because all 11 protein fractions contained some stimulatory activity, the results suggested that the protein constituents of these fractions were relatively nonspecific. Yet, of the several known proteins which were tested for activity (bovine serum albumin, ovalbumin, human γ-globulin, bovine pancreatic ribonuclease, and pig insulin) only bovine serum albumin proved to be active. An additional 8% of the stimulatory activity of the cytosol was present in the fraction containing the low molecular weight components and this was all attributable to its GSSG content. 相似文献
888.
On the existence of non-cycling germinative cells in human epidermis in vivo and cell cycle aspects of psoriasis 总被引:3,自引:0,他引:3
Seymour Gelfant 《Cell proliferation》1982,15(4):393-397
Abstract. This report deals with the controversies of whether all germinative epidermal cells in human epidermis are in the cycling state and whether stimulated hyperproliferation of psoriatic epidermis is due to a shortening of the cell cycle time or to a recruitment of non-cycling germinative epidermal cells. Experiments were performed on human subjects in vivo . Continuous infusion of [3 H]thymidine for 8½ days indicated that 40% of germinative epidermal cells reside in the non-cycling state. Proliferative stimulation by tape stripping indicated recruitment of non-cycling (G0 ) germinative epidermal cells in both normal and psoriatic skin, and a prolongation (rather than a shortening) of cell cycle traverse in activated psoriatic epidermal cells. 相似文献
889.
Rats injected with LiCl after they consumed a sweetened milk solution subsequently avoided the milk. ACTH4--10 injection prior to a retention test for the aversion augmented the behavioral measure of the aversion. Rats consuming milk paired earlier with LiCl showed elevated plasma levels of corticosterone. The augmented avoidance response in ACTH4--10 injected rats was not paralleled by an augmented pituitary-adrenal response. 相似文献
890.