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61.
62.
Trisomy 18 associated with a familial translocation t(Bq-; 18q+) 总被引:2,自引:0,他引:2
63.
Replication of nucleolus-associated DNA during "G2 phase" in Physarum polycephalum 总被引:1,自引:1,他引:0
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![点击此处可从《The Journal of cell biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
In the myxomycete, Physarum polycephalum, the bulk of nuclear DNA replication occurs during a period of a few hours immediately following upon mitosis. During the remainder of the intermitotic period, incorporation of thymidine-3H continues at a low rate in the region of the nucleolus (radioautographs). A few nuclei incorporated thymidine-3H into the extranucleolar chromatin at a high rate at all times of the intermitotic period. These nuclei were exceptionally large and they frequently contained several small nucleoli of different sizes rather than the one, central nucleolus which is characteristic of a normal interphase nucleus. 相似文献
64.
Phytochrome Control of Maize Leaf Inorganic Pyrophosphatase and Adenylate Kinase 总被引:1,自引:1,他引:0
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![点击此处可从《Plant physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Brief exposure of etiolated maize seedlings to light induces large increases in adenylate kinase and inorganic pyrophosphatase activity of the leaf in the following 48 hr in the dark. Red light is more effective than white or far red light, and far red reverses the effect of red light, indicating phytochrome control. Out of several tested, only these 2 enzymes appear to be coordinately induced, which is consistant with their close functional relationship. For inorganic pyrophosphatase, light treatment induces biosynthesis of a distinctive form of the enzyme characteristic of chloroplasts, readily separable from the enzyme characteristic of etiolated tissue. 相似文献
65.
G. M. Besser P. W. P. Butler J. Landon Lesley Rees 《BMJ (Clinical research ed.)》1969,4(5682):528-530
Plasma fluorogenic corticosteroid and immunoreactive growth hormone levels rose significantly after the intravenous administration of methylamphetamine to healthy young men at various times of the day. The rise in corticosteroids was most pronounced in the evening and was accompanied by an increase in circulating levels of immunoreactive corticotrophin. Oral dexamphetamine also resulted in significant rises in plasma corticosteroids but not in growth hormone. These hormonal changes were accompanied by evidence of mild central stimulation. Though they may be part of an associated and non-specific response, it is more likely that they represent specific effects of amphetamines on centres in the hypothalamus or midbrain controlling secretion of corticotrophin and growth hormone releasing factors. 相似文献
66.
A. W. Asscher M. Sussman W. E. Waters Joy A. S. Evans H. Campbell K. T. Evans J. Edmund Williams 《BMJ (Clinical research ed.)》1969,1(5647):804-806
Short courses of nitrofurantoin and ampicillin produced an immediate cure in 80% of adult non-pregnant bacteriuric women. Of the subjects so treated, 55% remained cured at the end of one year. Over the same follow-up period 36% of untreated bacteriuric women developed a spontaneous remission of bacteriuria. Treatment failed to prevent the development of symptomatic infection, and the reinfections which followed successful treatment were more commonly associated with the development of symptoms than the persistent or relapsing infections in untreated or unsuccessfully treated subjects.It is concluded that a search for bacteriuria in non-pregnant women is unlikely to be of value as a preventive measure, since in many instances it fails to detect urinary tract infection at an early stage and since treatment by methods suitable for large-scale use is ineffective. 相似文献
67.
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69.
The carnitine-independent oxidation of palmitate plus malate by moth flight-muscle mitochondria 总被引:2,自引:2,他引:0
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Edmund Stevenson 《The Biochemical journal》1968,110(1):105-110
Mitochondria isolated from the flight muscle of the southern armyworm moth, Prodenia eridania, can oxidize palmitate+malate very rapidly. Added carnitine had no effect on the rate of oxidation of palmitate+malate by flight-muscle mitochondria from two species of moths, and carnitine palmitoyltransferase could not be detected in Prodenia by direct assay. Palmitoylcarnitine was not oxidized by moth mitochondria, but when added in low concentrations it reversibly suppressed the oxidation of palmitate. The evidence indicates that carnitine is not involved in fatty acid degradation by moth flight muscle. Added thiols, including CoA, also suppressed palmitate+malate oxidation. An ATP-dependent fatty acyl-CoA synthetase is present in moth mitochondria. 相似文献
70.