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1.
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Brca2 is coordinately regulated
with Brca1 during proliferation and
differentiation in mammary epithelial cells 下载免费PDF全文
JayantV. Rajan Man Wang SandraT. Marquis LewisA. Chodosh 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(23):13078-13083
We have analyzed the expression of the breast cancer susceptibility gene, Brca2, in mammary epithelial cells as a function of proliferation and differentiation. Our results demonstrate that Brca2 mRNA expression is tightly regulated during mammary epithelial proliferation and differentiation, and that this regulation occurs coordinately with Brca1. Specifically, Brca2 mRNA expression is up-regulated in rapidly proliferating cells; is down-regulated in response to serum deprivation; is expressed in a cell cycle-dependent manner, peaking at the G1/S boundary; and is up-regulated in differentiating mammary epithelial cells in response to glucocorticoids. In each case, an identical pattern of expression was observed for Brca1. These results indicate that proliferative stimuli modulate the mRNA expression of these two breast cancer susceptibility genes. In addition, the coordinate regulation of Brca1 and Brca2 revealed by these experiments suggests that these genes are induced by, and may function in, overlapping regulatory pathways involved in the control of cell proliferation and differentiation. 相似文献
3.
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
7.
R B Bourne H Bitar P R Andreae L M Martin J B Finlay F Marquis 《Canadian journal of surgery》1988,31(1):43-45
Absorbable sutures are initially equal or superior to nonabsorbable sutures in terms of tensile strength but are absorbed at variable rates by the action of hydrolysis. This study demonstrated that the in-vivo half-life tensile strength of the braided absorbable sutures polyglycolic acid (Dexon Plus) and polyglactin 910 (Vicryl) is 2 weeks, whereas those of the monofilament absorbable sutures polyglyconate (Maxon) and polydioxanone (PDS) are 3 and 6 weeks respectively. The addition of a single hitch or six knots reduced the in-vitro tensile strength by 30% to 35%. Polyglyconate (Maxon) suture demonstrated the best in-vitro knot security. 相似文献
8.
Distinction between the myoclonus-related potential and the epileptic spike in epilepsia partialis continua 总被引:1,自引:0,他引:1
P Chauvel C Liegeois-Chauvel P Marquis J Bancaud 《Electroencephalography and clinical neurophysiology》1986,64(4):304-307
Neurophysiological analysis of spontaneous and reflex-triggered myoclonus in a case of epilepsia partialis continua is reported. A central positive wave (P1), part of the high voltage evoked potential and of the spontaneous spike, is held to be responsible for the myoclonic jerk. It is demonstrated that P1 is a distinct phenomenon from both the evoked potential and the epileptic spike, and so should be identified as a myoclonus-related potential (MRP). 相似文献
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Three internal and three external outcome measures generated data for this longitudinal study. The internal outcome measures were nursing GPA, nonnursing GPA, and clinical evaluations of students during eight clinical rotations. The external evaluations were NCLEX scores, the graduates' self-rating of their competency in meeting program objectives, and their immediate supervisors' ratings on the identical competency rating scale. Data analyzed using Pearson correlation coefficients revealed significant correlations among all internal measures of academic outcomes with one external measure, the NCLEX score. There was no correlation between any nursing measure of outcome and the supervisor's ratings. There was a modest correlation between the supervisors' rating and the nonnursing GPA. The faculty clinical evaluation was the only significant correlation found between the alumni rankings and any other measure of outcome. There was no correlation between the supervisors' and the graduates' ratings. 相似文献