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31.
32.
提取青蒿素实验条件的研究 总被引:8,自引:0,他引:8
对从青蒿叶中提取青蒿素的各种方法及实验条件进行实验比较,结果表明,采用索氏提取法及以B号油为溶剂,具有提取率较高,时间短、操作方便、耗油少等特点。 相似文献
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34.
以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。 相似文献
35.
36.
原子吸收法测定茶叶中的微量元素和溶出率 总被引:3,自引:0,他引:3
用火焰原子吸收法测定了3种云南茶叶中的铜、锌、锰、铁和铬的含量及溶出率。其中铜、锌、锰、和铁的溶出率均是红茶和绿茶大于沱茶,铬的溶出率则相近。 相似文献
37.
中药泡洗治疗糖尿病足90例疗效分析 总被引:1,自引:0,他引:1
目的为了观察中药泡洗对糖尿病足的疗效。方法对90例糖尿病足患者用中药(方剂组成:桃仁、红花、桂枝、没药、乳香、花椒、川芎等各10g)水煎制后分为2袋各300ml配合足浴仪泡洗,2次,d,30min/次,10d为1疗程。结果全组90例患者显效66例,有效24例,总有效率100%。结论中药泡洗治疗糖尿病足疗效确切。 相似文献
38.
Objective To evaluate the character of the collagen-chitosan-chondroitin sulfate scaffold seeded with rat adipose tissue-derived stromal cells. Methods A dipose tissue were harvested from 6 weeks old Wistar rats and the stromal cells were harvested by type Ⅰ collagenase and then cultured in vitro. Type Ⅰ collagen was fully mixed with chitosan, freeze-dried and cross-linked with chondroitin sulfate, then freeze-dried again and sterilized by ethylene oxide. The pore diameter, water content, porosity of the scaffold were tested. The adipose tissue-derived stromal cells were digested, seeded into the plates, scaffold, and cen-trifuged into pellet, and then induced into cartilage. MTT detection for cell proliferation was done. After 3 weeks, the cell morphology, and cell proliferation and adhesion were observed, and chondrngenic differenti-ation was also analyzed. Results The pore diameter, water content, porosity tested for the scaffold showed an appropriate form. Cell proliferation showed faster in the scaffold and pellet culture system after 5 day, there was still cell proliferation in the scaffold system after 14 days but no obvious changes in the pellet cul-ture system; ceils on the scaffold proliferated densely showed by histological staining, but there was a scaf-fold structure residues in the inner layer. The finding of type Ⅱ immunohistochemistry stain showed that cells express strong positive for type Ⅱ collagen in the scaffold and pellet culture system whereas it was weakly positive in the plate culture system; the specific mRNA for cartilage, type Ⅱ collagen, aggrecan and SOX-9 were expressed in all three systems showed by RT-PCR, but type X collagen was expressed continu-ously in the plate culture system and expressed after 21 days in the pellet culture system, whereas it was not detected in the collagen-chitosan-chondroitin sulfate scaffold system. Conclusion The parameters of the collagen-chitosan-chondroitin sulfate scaffold were suitable in our study. The results suggested that it can promote the adipose tissue-derived stromal cells proliferation and chondrogenic differentiation better than the plate and pellet culture systems and maintain the phenotype of chondrocytes well; it is the optimal choice for cartilage tissue engineering in the future. 相似文献
39.
精子洗涤对精液中HBV DNA含量的影响 总被引:8,自引:0,他引:8
目的:检查HBV感染者精液是否存在乙型肝炎病毒(HBV),探讨精子洗涤是否能去除其中的HBV DNA。方法:用实时荧光定量PCR(FQ-PCR)法检测57名血清HBsAg阳性患者精液中HBV DNA,采用Percoll非连续梯度离心及上游法分离其中21份精液,并对洗涤后标本进行HBV DNA检测。结果:62份精液标本中有15份HBV DNA阳性,阳性率为24.19%;21份用于洗涤的精液标本中有,有7份HBV DNA阳性,洗涤后仍有6份标本阳性。结论:部分HBV感染者精液具有传染性,精子洗涤不能完全去除精液中的乙肝病毒。将HBV感染者的精液用于人工授精或体外受精应慎重。 相似文献
40.
Cre recombinase-mediated site-specific recombination
between plant chromosomes. 总被引:16,自引:3,他引:13 下载免费PDF全文
M Qin C Bayley T Stockton D W Ow 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(5):1706-1710
We report the use of the bacteriophage P1 Cre-loxsystem for generating conservative site-specific recombination between tobaccochromosomes. Two constructs, one containing a promoterless hygromycin-resistancegene preceded by a lox site (lox-hpt) and the other containing a cauliflowermosaic virus 35S promoter linked to a lox sequence and the cre coding region(35S-lox-cre), were introduced separately into tobacco plants. Crosses betweenplants harboring either construct produced plants with the two constructssituated on different chromosomes. Plants with recombination events wereidentified by selecting for hygromycin resistance, a phenotype expressed uponrecombination. Molecular analysis showed that these recombination eventsoccurred specifically at the lox sites and resulted in the reciprocal exchangeof flanking host DNA. Progenies of these plants showed 67-100% cotransmission ofthe new transgenes, 35S-lox-hpt and lox-cre, consistent with the preferentialcosegregation of translocated chromosomes. These results illustrate thatsite-specific recombination systems can be useful tools for the large-scalemanipulation of eukaryotic chromosomes in vivo. 相似文献