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121.
Eradication of multiple nodules, papules, and plaques of pigmented basal cell epitheliomas of the back of one patient was achieved by nine months of daily treatment with 5% fluorouracil cream. Such topical chemotherapy offers the physician an alternative to surgery and radiation in treating patients who have widespread nodular superficial epitheliomas. The need for a prolonged period of treatment and follow-up is emphasized. 相似文献
122.
PA Sullivan CY Soon WJ Schreurs JF Cutfield MG Shepherd 《Canadian Metallurgical Quarterly》1977,165(2):375-383
1. An improved purification was developed for L-lactate oxidase from Mycobacterium smegmatis. 2. The mol.wt. of the native enzyme by a sedimentation-equilibrium analysis was 345 000, and other ultracentrifuge methods gave values in the range 345 000-350 000. 3. An amino acid analysis, determinations of protein and flavin, a sedimentation-velocity analysis and an approach to equilibrium analysis gave values for the subunit mol.wt. in the range 43 500-47 000. 4. It was concluded that L-lactate oxidase contains eight subunits of mol.wt. 43 500. 5. Cross-linking of the subunits with dimethyl suberimidate and electron-microscopy studies were consistent with an octameric structure. 相似文献
123.
124.
The free sulfhydryls of brain tubulin prepared by cyclic polymerization procedures both with and without glycerol have been examined. The average free sulfhydryl titer of tubulin prepared with glycerol (7.0 sulfhydryls/55,000 mol wt) is greater than that of tubulin prepared without glycerol (4.0 sulfhydryls/55,000 mol wt). Diamide, a sulfhydryl-oxidizing agent, inhibits the polymerization of tubulin. Diamide also disperses the 20S and 30S oligomers of tubulin seen in analytical ultracentrifuge patterns of tubulin solutions and, depending on the temperature at which diamide is added, converts all or part of the oligomeric material to 6S dimers. Electron microscopy demonstrates that diamide also destroys the 450-A ring structures characteristic of tubulin solutions. All diamide effects are reversible by the addition of 10 mM dithioerythreitol, a sulfhydryl-reducing agent. That diamide interacts with sulfhydryls on tubulin is directly demonstrated by a 50% decrease in the free sulfhydryl titer of tubulin measured after diamide treatment. Concentrations of CaCl2 which inhibit polymerization also decrease the free sulfhydryl titer of tubulin. 相似文献
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127.
Films of linolenic acid supported on chromatographic type silica gel undergo autoxidation at a rate which is slow compared
to that in homogeneous phase at low surface coverage but comparable to it at coverages approximating a close-packed monolayer.
The new observation reported here is that these surface phase oxidations are chemiluminescent. The quantum yield is ca. 10−12 quanta per molecule of fatty acid reacted for a close-packed monolayer and remains approximately constant with decreasing
coverage. The emission intensity is temperature dependent, with an apparent activation energy of 10 kcal mol−1, and shows an induction period for close-packed monolayers. The emission spectrum contains a component consistent with excited
state ketone emission and a low energy component, ca. 600+ nm, which could be due to singlet oxygen emission. The existence
of the emission means that surface autoxidation reactions can be followed in place; the nature of the emission may provide
insight into the autoxidation mechanism beyond that which may be inferred from conventional rate measurements. 相似文献
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129.
MG Astapenko W Otto TM Trofimowa H H?ntzschel B Tautenhahn D Reinelt H Treutler AI Speranskij NM Mylow WA Duljapin TA Tarasenkowa 《Canadian Metallurgical Quarterly》1976,31(16):641-646
On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis. 相似文献
130.