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Cyclophosphamide, given in widely spaced doses, was used in the treatment of a patient with pemphigus vulgaris and a patient with bullous pemphigoid. To our knowledge, this form of therapy has not previously been reported in these two diseases. The distinct advantages of the larger intermittent dose method of cyclophosphamide therapy over the more conventional daily dose regimen are discussed. 相似文献
44.
High resolution studies on the pattern of induced exchanges in the human karyotype 总被引:12,自引:0,他引:12
Dr. Marina Seabright 《Chromosoma》1973,40(4):333-346
The pattern of breakage and exchange induced by X-irradiation of human lymphocytes at G1 has been analysed in PHA transformed cultures at X1 metaphase in cells treated with trypsin. All the events observed occurred in interband segments. Moreover, as far as the autosomes were concerned, these events appear to be at random in relation to trypsin interband length but give some indication of non-randomness when total chromosome length is considered. The X and Y chromosomes, on the other hand, show far fewer breaks than would be expected whichever criterion is adopted, and in particular appear to be isolated from the autosomes with respect to the occurrence of exchange events. — The analysis of specific break points in relation to trypsin banding sequences, makes it clear that conclusions regarding chromosome rearrangements based solely on conventional preparations may be misleading. 相似文献
45.
ION-INDUCED ULTRASTRUCTURAL TRANSFORMATIONS IN ISOLATED MITOCHONDRIA : The Energized Uptake of Calcium 总被引:10,自引:4,他引:6 下载免费PDF全文
The energized uptake of low levels of Ca2+ in the presence and absence of phosphate by isolated rat liver mitochondria, and the perturbation effected by this activity on ultrastructural and metabolic parameters of mitochondria have been investigated. In the presence of phosphate, low levels of Ca2+ are taken up by mitochondria and result in various degrees of ultrastructural expansion of the inner mitochondrial compartment. This indicates that low levels of Ca2+ in the presence of phosphate, are accumulated in an osmotically active form into the water phase of the inner compartment. The first clearly observable quantitative increase in the volume of the inner compartment occurs after the accumulation of 100 nmoles Ca2+/mg protein. An accumulation of 150–200 nmoles Ca2+/mg protein, which is equivalent to the osmolar concentration of endogenous K+, is required to effect a doubling of the volume of the inner compartment. This degree of osmotic perturbation occurs as mitochondria transform from a condensed to an orthodox conformation. The osmotically induced orthodox conformation differs from the mechanochemically induced orthodox conformation previously described, in that its development is concomitant with a marked decrease in acceptor control and oxidative phosphorylation efficiency and it fails to transform to a condensed conformation in response to addition of ADP. In the absence of added phosphate, a maximum of 190 nmoles Ca2+/mg protein was found to be taken up by mitochondria (state 6). Ca2+ is apparently bound under state 6 conditions since the uptake does not effect an ultrastructural expansion of the inner compartment. Phosphate added after state 6 Ca2+ binding, however, results in an immediate ultrastructural expansion of the inner compartment. The addition of phosphate to mitochondria in the absence of exogenous Ca2- fails to effect an osmotic ultrastructural transformation. Under state 6 conditions, the binding of between 40 and 190 nmoles Ca2+/mg protein results in the formation of dense matrix inclusions which appear to be composed of tightly packed, concentrically oriented membranes. Under conditions in which the bound Ca2+ is subsequently released, there is a concomitant loss in the density of these matrix inclusions, leaving behind morphologically distinct membrane whorls in the mitochondrial matrix. 相似文献
46.
Die Suppression der außerkaryotisch bedingten Streptomycin-Abhängigkeit bei Chlamydomonas reinhardii
Zusammenfassung Die Streptomycin-Abhängigkeit der Mutante sd3 wird außerkaryotisch vererbt. Nach Übertragung auf streptomycin-freies Medium entstehen in einer Häufigkeit von 10-7 bis 10-6 streptomycin-empfindliche Zellen. Diese Revertanten unterscheiden sich in verschiedenen Merkmalen von dem ebenfalls streptomycin-sensiblen Wildtyp. Die Reversion kommt also nicht durch Rückmutation zustande. Durch Kreuzungsexperimente konnte gezeigt werden, daß die Mutation, die zur Suppression der Streptomycin-Abhängigkeit führt, auf der extranucleären DNS stattgefunden hat.
Suppression of the extranuclear streptomycin dependence in Chlamydomonas reinhardii
Summary The streptomycin-dependent mutant sd3 shows uniparental inheritance. From their transfer on streptomycin-free medium streptomycin-sensitive cells result in a frequency of 10-7 to 10-6. These revertants differ in several marks from likewise sensitive wild-type cells. Therefore they were formed not by backmutation. Crossings showed, that also this suppression took place on the extranuclear DNA.相似文献
47.
The streptomycin sensitive (ss-) revertants of the streptomycin dependent mutant sd3 segregate on streptomycin medium again sd-cells. This sd-segregation decreases continuously with increasing time of cultivation until zero-level is reached. The revertant R 20 differ from the other revertants mainly that the rate of segregation remaining almost at the same high level a long time. But the results of clonings showed that also in R 20 the number of cells able to segregate sd-cells decreases. After 6 months, only 20% of the cells still possessed this ability. Former investigations showed that the ss-revertants still had sd-informations. These informations segregate in the following cell-divisions and produce again sd-colonies on the streptomycin medium. The rate of segregation was changing with the different clones. This proves the non-oriented distribution of the sd- and ss-gene copies at the mitotic division. The clonings demonstrate also the existence of much more than 2 copies. According to Sager and Ramanis the genes of the chloroplast exist at the most in 2 copies. If the statement should be true in principle for all vegetative cells, then the sd-information cannot be in the chloroplast. It must be located in the mitochondria. 相似文献
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Ruth C. Steinkamp Clarence L. Young Dolores Nyhus Arnold E. Greenberg 《The Western journal of medicine》1968,109(2):126-133
The amount of sodium ion in water used for ingestion may be critical in effective use of a low sodium dietary regimen. Waters containing not over 20 mg of sodium per liter are provided for in the sodium restricted diets set forth by the American Heart Association. For diets containing more than 500 mg of sodium a day, waters of greater sodium content may be used if proper dietary adjustments are made.While assessment of the long-term average sodium content of a community water supply is difficult, the determined values for sodium lend to classification within range categories. The larger community water supplies in California are presented within several range categories of sodium content.The more commonly used water softeners add sodium to water. The sodium-restricted patient should be cautioned against their use. Similar consideration should probably be given to water supplies of retirement communities where the potential for disorders requiring sodium restriction is greater than in the general population. 相似文献
50.
Studies of accident-prone drivers emphasize the frequency of unstable, aggressive or antisocial personalities expressing themselves through the automobile as a real and a symbolic weapon. Such expressions may be voluntary or unconscious and may also lead a driver to injure himself or seek injury from others.Because of the great public danger from such drivers, it is urgent that judges and enforcers of the law recognize the psychic motivation in habitual violation and withhold driving privileges from violators until a psychic adjustment has been made. Physicians can contribute in gaining acceptance for this attitude of enforcement, and in setting up adequate psychiatric procedures for correction of violators. 相似文献