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11.
Human mini-chromosomes in mouse embryonal stem cells 总被引:3,自引:2,他引:3
We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb
in size into mouse embryonal stem cells. Although these human mini-
chromosomes are stable in hamster and chicken cells, they re-arrange or
segregate aberrantly in the embryonal stem cells and are rapidly lost in
the absence of selection. However, one of the mini-chromosomes re-
arranged, acquired mouse centromeric sequences and was then stably
maintained for at least 60 population doublings in culture. This mini-
chromosome, which is 4 Mb in size, is a candidate for a mouse germ line
chromosome vector.
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Auld GW Romaniello C Heimendinger J Hambidge C Hambidge M 《The Journal of school health》1999,69(10):403-408
This study modified a successful nutrition program to improve its transferability and potential for institutionalization. Specific aims were to determine: 1) if 16 nutrition lessons taught alternately by special resource teachers (SRT) and classroom teachers, could produce outcomes equivalent to 24 SRT lessons; and 2) teachers' reactions to the program. The quasi-experimental design used classrooms (19 treatment and 19 comparison) in matched schools. Surveys and plate waste measured children's outcomes, and classroom teachers were observed and interviewed. Treatment students showed greater knowledge and self-efficacy scores and consumed 0.36 more servings of fruits and vegetables at lunch. Behavioral differences between groups were greater when SRTs provided all instruction. Teachers supported the program and anticipated teaching more nutrition on their own, but noted serious structural barriers. Findings support the need for long-term contact to induce behavior change and the advantage of using teachers specifically trained in nutrition and experiential education. 相似文献
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Effect of genetic modification of acute inflammatory responsiveness on tumorigenesis in the mouse 总被引:1,自引:3,他引:1
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Possible role of endothelin-1 in the rabbit urinary bladder hyperplasia secondary to partial bladder outlet obstruction 总被引:1,自引:0,他引:1
Khan MA Shukla N Auld J Thompson CS Mumtaz FH Stansby GP Morgan RJ Mikhailidis DP 《Scandinavian journal of urology and nephrology》2000,34(1):15-20
OBJECTIVES: Urinary bladder hypertrophy and hyperplasia are common features of bladder outlet obstruction (BOO). The urinary bladder is known to synthesize endothelin-1 (ET-1), which is a potent vasoconstrictor peptide with mitogenic properties. Using an animal model of partial BOO, we investigated the potential role of ET-1 and its receptor subtypes (ET(A) and ET(B)) in bladder smooth muscle cell (SMC) proliferation. MATERIALS AND METHODS: Partial BOO was produced in adult male New Zealand White rabbits. After 3 weeks, the bladder was removed and SMCs from the dome and bladder neck were grown using standard explant methodology. At passage 2, the cells were made quiescent and then further incubated in foetal calf serum (FCS), control age-matched rabbit serum (CRS) or partial BOO serum (BRS) in the presence or absence of ET(A)-antagonist (BQ123) or ET(B)-antagonist (BQ788). SMC proliferation was then measured 24 h later with 5-bromo-2'deoxy-uracil and by cell counting using a haemocytometer at 48 h. Immunostaining for alpha-actin was performed on detrusor and bladder neck cells to confirm the presence of smooth muscle cells. RESULTS: BQ123 and BQ788 did not influence detrusor or bladder neck SMC proliferation in FCS or CRS. However, in the presence of BRS, BQ123 and BQ788 (100 nmol/L) significantly (p = 0.008) inhibited detrusor and bladder neck SMC proliferation. Cell counts were significantly reduced from the detrusor (p = 0.03, p = 0.01 with BQ123 and BQ788, respectively) and bladder neck (p = 0.01 for both BQ123 and BQ78). CONCLUSIONS: These results suggest that ET antagonists may have a role in preventing SMC hyperplasia associated with partial BOO. 相似文献
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Secretion of matrix metalloproteinase‐3 by co‐cultured pigmented and non‐pigmented human trabecular meshwork cells following selective laser trabeculoplasty 下载免费PDF全文
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单克隆抗体博来霉素A6偶联物对白血病细胞特异性结合与内化 总被引:2,自引:0,他引:2
抗CCT2单克隆抗体博来霉素A6偶联物可吸附胶体金颗粒(McAb-A6-Au)。电镜观察表明,在4℃,1h,表面有McAb-A6-Au颗粒的CEM细胞最高达78%;在37℃,4h,内化McAb-A6-Au颗粒的CEM细胞高达72%。而抗原性无关的U937细胞仅为14%。并且McAb-A6-Au颗粒能直接穿过细胞膜、核膜进入细胞浆和细胞核。37℃,1h已有10~18%的CEM细胞核内有McAb-A 6-Au颗粒。实验结果提示了单抗与博来霉素A6的偶联物与选择性地结合靶细胞,而且进入细胞速度快、穿透力强,有可能成为治疗白血病药物。 相似文献