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991.
A method for hemoglobin electrophoresis is described, using acrylamide gelas the supporting media. The advantages and characteristics of this gel arementioned. Clear and distinct separations of hemoglobin types obtained after60 minutes electrophoresis in a vertical cell are illustrated. It is felt that theuse of this gel affords a simple and rapid method for the detection and quantitation of hemoglobin abnormalities. Accepted on December 15, 1961 相似文献
992.
ANTHONY DU VIVIER ROBERT BIBLE Jr. ROBERT K. MIKURIYA RICHARD B. STOUGHTON 《The British journal of dermatology》1976,94(1):1-6
A new, rapid, simple and accurate procedure for extracting DNA from the epidermis is described involving hydroxyapatite. This compound has an unique property of high affinity for double stranded native DNA, but none for RNA and protein. The technique has been applied to a hairless mouse model for screening systemic and topical agents for cell inhibitory properties in proliferating epidermis for potential use in the therapy of psoriasis. Mitotic counts, autoradiography and a standard chloroform procedure for isolating DNA have confirmed the results obtained using hydroxyapatite column chromatography. In addition, compounds which are known to be effective in psoriasis, have been found to be effective in the system suggesting that it should be a good predictive screen for new therapies. Of several compounds screened for topical activity, cycloheximide has been found to be very effective in the system and preliminary clinical studies confirm its efficacy in psoriasis. 相似文献
993.
Rupture of the ligamentum patellae tends to occur within Its substance, in association with oral steroid medication, and/or active collagen disease. By comparison, avulsion of tendon from bone tends to occur in patients who are not taking oral steroid preparations and are not actively affected by one of the collagen diseases. Surgical repair produces excellent results. 相似文献
994.
WILLIS JANINE A.; STOWELL KATHRYN M.; CROW KATHRYN E.; BATT RICHARD D.; HARDMAN MICHAEL J. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1985,20(3):293-298
Since cytosolic malate dehydrogenase has been shown to playa role in the regulation of liver cytosolic [NAD+]/[NADH] redoxstate during ethanol metabolism, it is possible that differencesin this enzyme could cause differences in response to ethanol.The present study demonstrates that the isozyme pattern of thiscytosolic enzyme in whole blood samples is the same as thatin liver and that the pattern does not differ in alcoholic andcontrol subjects. A marginally significant elevation of activityof malate dehydrogenase in blood from alcoholic subjects isreported. Further studies are needed to confirm this latterfinding and to assess fully its possible significance. 相似文献
995.
RICHARD P. ELLEN DOUGLAS BRATTHALL MARGARETA BORGSTRÖM THOMAS P. HOWLEY 《European journal of oral sciences》1983,91(4):263-273
Abstract – The objectives were to determine the degree of Actinomyces agglutinating activity in human saliva and to begin characterizing the agglutination mechanism. Agglutination titres of whole saliva collected from adults and 6-yr-old children were compared. Titres for A. naeslundii were always higher than for A. viscosus. The mean A. naeslundii titre for the adults’ and children's samples were equivalent. The children had a slightly lower mean titre than the adults for A. viscosus. No correlation was found between IgA concentration and agglutination titre. Agglutinating activity was partially impaired by incubation with anti-IgA serum. Activity in submandibular/sublingual saliva was resistant to heat at 56°C but sensitive to boiling. Boiling the bacteria had no effect. In sugar inhibition tests, only galactosides (β-Gal) and glucosamine (for A. viscosus) affected Actinomyces agglutination but impairment was only temporary. Agglutinating activity was diminished by incubating saliva with hydroxyapatite. Thus, Actinomyces agglutinins 1) are probably distinct from IgA but may complex with it; 2) may include both β-Gal and higher affinity sites; and 3) may contribute to salivary pellicle. 相似文献
996.
RICHARD E. GALARDY UMESH B. GOLI E. CARROLL TEATER DAMIAN GROBELNY 《Chemical biology & drug design》1988,32(4):292-297
Nα-(Phenethylphosphono)-l -alanyl-l -proline 1, a potent inhibitor of angiotensin converting enzyme, exhibits two 31P n.m.r. resonances (intensity ratio one to one), which exchange with a constant (k1) of about 1 s?1 and a free energy of activation ΔG*=~ 20kcal/mol at 23° in deuterated dimethylsulfoxide. Two resonances in exchange are also observed in deuterium oxide at pH 7.5. Thus the exchanging 31P resonances report the s-cis, s-trans conformational equilibrium about the alanyl-proline peptide bond. Similar results were observed with Nα-[(O-phenyl)-phenethylphosphono]-l -alanyl-l -proline 2. Nα -(O-phenylphospho)-l -alanyl-l -proline, 3 Nα-(O, O′-diphenylphospho)-l -alanyl-l -proline 4, and Nα-[2-(2-oxo-1, 3, 2-dioxaphosphiranyl)]-l -alanyl-l -proline 5 in deuterated dimethyl sulfoxide, deuterium oxide, and deuterochloroform. A 13C n.m.r. spectrum of 5 confirmed the presence of s-cis and s-trans resonances for the proline carbons in the same intensity ratio observed by 31P n.m.r. 相似文献
997.
998.
Transport of lysine and glycine was studied in cultured fibroblasts of a patient with Lowe's oculocerebrorenal syndrome. Although patients with this syndrome demonstrate renal and intestinal amino acid transport defects, no abnormality was found in our study. 相似文献
999.
SEYMOUR FURMAN RICHARD BRODMAN FRANK PANNIZZO JOHN D. FISHER 《Pacing and clinical electrophysiology : PACE》1984,7(3):572-579
Implantation of a defibrillator may be by a mixed technique of transvenous leads and subcostal thoracotomy. An alternative approach is placement of all defibrillator leads and possible pacemaker leads via median sternotomy. All sensing leads, either for a defibrillator or a pacemaker, should be bipolar to provide maximal rejection of interference signals. Interpretation of the electrogram requires analysis of the pathologic electrogram to distinguish it from the "normal" electrogram for that patient and may require several leads to determine the activation sequence; which will allow diagnosis of a tachycardia in a fashion similar to that performed by a human observer. 相似文献
1000.