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871.
We have characterized a 32,000-36,000-dalton sialoglycoprotein group that is an integral component of the lipoprotein complex called pulmonary surfactant. Our results from the cell-free translation of human lung RNA show that this protein consists of two similarly-sized precursor components of about 29,000-31,000 daltons. Tunicamycin treatment of the lung tissue prevents formation of the normal protein and results in the accumulation of these precursor components which are also seen under normal conditions in very small amounts. Although in vitro translation in the presence of dog pancreatic microsomes suggests that a cleavable signal peptide sequence is present in these precursor molecules, it does not appear that this cleavage occurs in vivo.  相似文献   
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874.
The Kaufman-McKusick syndrome (MK 23670) is a rare autosomal recessive disorder characterized by the triad of hydrometrocolpos, postaxial polydactyly, and congenital heart disease. Multiple other anomalies have been ascribed to this syndrome. Hydrometrocolpos, especially if unrecognized, may be a serious, life-threatening condition in the newborn girl. Forty-four cases have been so far reported in the literature. A great phenotypic variability occurs in this syndrome, therefore making it very difficult to identify the disorder at its presentation and classify it correctly. We shall hereafter review current data regarding the prominent clinical features, the diagnosis and treatment of this syndrome. Problems in genetic counseling will be discussed.  相似文献   
875.
The possibility of inducing systemic tolerance in animals by feeding them with ovalbumin and human serum was studied on mice, rats and rabbits. Antibodies to ovalbumin, human serum albumin and immunoglobulins (IgG, IgA, IgM) were determined by the passive hemagglutination test in the sera of the test and control animals after the second immunization made through a parenteral route. Tolerance to all the antigens under study was obtained in mice and rats, while in rabbits such feeding was found to produce the priming effect. The degree of tolerance was the greater, the more was the dose of the antigen and the longer was the period of feeding. Different proteins showed varying tolerogenic activity; the same degree of tolerance in mice was obtained by feeding them with IgG in a dose of 0.3-0.5 mg and with ovalbumin or human serum albumin in a dose of 6-12 mg (per gram of body weight). Tolerance was determined on day 3 after the course of feeding was over; in 3 weeks tolerance essentially decreased, and in 1.5-2 months it was replaced by normal reactiveness. Tolerance induced by the oral administration of antigens proved to be immunologically specific.  相似文献   
876.
H T Miller  W Yesus  L Golden  T Cooper  S Baxter 《Life sciences》1986,39(15):1367-1373
The isolation and identification of a material present in the plasma of hypertensive dogs and hypertensive human patients has been under study since 1972. The earliest experiments in relation to this work, noted that plasma from hypertensive dogs cause a hyperresponse to norepinephrine when both were administered by way of the vein. Employing a rat assay system that consisted of an anesthetized rat with polyethylene catheters in the vein for giving norepinephrine and the test fractions and a catheter in the artery for blood pressure monitoring, fractions from hog kidney were tested for hyperresponsiveness activity. The active material is very comparable to cyclic AMP in molecular weight, ultraviolet spectrum, paper chromatography, Enzyme hydrolysis and activity in the anesthetized rat system. This evidence indicates that the hyperresponsiveness factor of renal origin is cyclic AMP.  相似文献   
877.
The appearance of G2-chalone in the cytoplasm of the intermediate cell layer and partly in the periderm of 17-day-old rat embryo epidermis has been demonstrated by the indirect method of Coons using a monospecific antiserum. G2-chalone was absent from the basal cell layer of 17--21-day-old embryos and of the newborn rats. It was found in all the epidermal layers in 2--5-day-old postnatal rats, while in 6--9-day-old animals it was primarily detected in the cytoplasm of spinous and basal cells. Thus the localization of epidermal G2-chalone typical for defined tissue becomes stabilized at the end of epidermis histogenesis.  相似文献   
878.
A simple and accurate technique for the determination of the heat resistance of spores is described. The technique combines a modified capillary tube method with a solid heating block. The come-up time of spore suspensions was found to be short and simple and accurate technique is suggested for the correction of the come-up times. Experimental results are presented for the destruction of spores of Bacillus stearothermophilus at 120 which indicates the accuracy and reproducibility of the new method.  相似文献   
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The finger and palmar prints of 60 women with breast carcinoma were studied. The results were compared with two groups of healthy women, the first consisted of old women and the second of young women. The dermatoglyphics seem to be of little use in the diagnosis of cancers of ectodermic origin. Supported by M.P.I. 60%, 1983  相似文献   
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