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71.
Summary

We have confirmed previous time-lapse microscopic observations (Suzuki 1985) using Chinese hamster hai and V79 cells. The proportion of non-dividing to dividing cells was the same under conditions of potentially lethal damage (PLD) repair and non-PLD repair after irradiation with 60Co γ-rays. This finding suggested that the radiation-induced damage to cellular DNA was similarly repaired so that cells undergo a first division to the same extent under both sets of conditions. In fact, direct measurement of double-strand breaks (dsb) in DNA from the two cell lines by the neutral elution technique showed no differences either in the initial amount of damage or in the time-course under conditions promoting or preventing PLD repair. These results indicate that PLD repair (i.e. an increase in cell survival) cannot be simply explained by a difference in the repair of dsb, but it can perhaps be explained by assuming that DNA damage is repaired with either fewer or more errors in the presence or absence of PLD repair respectively.  相似文献   
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Japanese whiting (Sillago japonica) are a relatively common species that inhabit coastal shallow waters in Japan and are the target species in an important recreational fishery. We isolated eleven candidate microsatellite loci from a small insert genomic DNA library of S. japonica. We screened for polymorphisms in the eleven loci using wild individuals (n = 48) collected from Suounada Sound, in the Seto Inland Sea, Japan. The number of alleles per locus ranged from 6 to 26 with no evidence of linkage disequilibrium. Observed heterozygosity ranged from 0.58 to 0.98 with one locus exhibiting a significant departure from Hardy–Weinberg equilibrium. A test for cross-amplification using the closely related species, Sillago parvisquamis yielded scoreable peaks and a high level of polymorphism in four loci. These polymorphic microsatellites can be used to identify population structure in S. japonica and provide potential markers for the endangered S. parvisquamis.  相似文献   
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The purpose of this study was to compare the effects of yoga with an active control (nonaerobic exercise) in individuals with prehypertension and stage 1 hypertension. A randomized clinical trial was performed using two arms: (1) yoga and (2) active control. Primary outcomes were 24‐hour day and night ambulatory systolic and diastolic blood pressures. Within‐group and between‐group analyses were performed using paired t tests and repeated‐measures analysis of variance (time × group), respectively. Eighty‐four participants enrolled, with 68 participants completing the trial. Within‐group analyses found 24‐hour diastolic, night diastolic, and mean arterial pressure all significantly reduced in the yoga group (?3.93, ?4.7, ?4.23 mm Hg, respectively) but no significant within‐group changes in the active control group. Direct comparisons of the yoga intervention with the control group found a single blood pressure variable (diastolic night) to be significantly different (P=.038). This study has demonstrated that a yoga intervention can lower blood pressure in patients with mild hypertension. Although this study was not adequately powered to show between‐group differences, the size of the yoga‐induced blood pressure reduction appears to justify performing a definitive trial of this intervention to test whether it can provide meaningful therapeutic value for the management of hypertension.  相似文献   
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