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1.
Fujio Murakami Yasushi Kobayashi Takashi Uratani Atsushi Tamada 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,96(2):181-193
The corticorubral projections in adult cats are primarily uncrossed. However, early in development and after early unilateral lesions of the sensorimotor cortex, crossed corticorubral projections are also observed. The present study was performed to disclose (1) whether the crossed projections originate from neuronal subpopulations different from those producing uncrossed ones and (2) how the neurons that give rise to the crossed projections in the lesioned animals are related to those occurring in normal development. We injected fluorescent latex microspheres into the red nucleus of two groups of animals: (1) intact kittens at postnatal week 3 and (2) kittens that had received unilateral ablation of the cerebral cortex at this stage and were then allowed to survive for at least 4 weeks. Red fluorescing microspheres were injected on one side and green ones on the other. In both normal and lesioned kittens, a number of cells in the cortex were labeled as a result of the contralateral as well as the ipsilateral injections, and no difference in size or distribution was found between the cells labeled from contralateral and ipsilateral injections. More than half of the cells labeled from contralateral injections were double-labeled in both groups of animals. These results indicate that individual corticorubral cells project bilaterally in normal development as well as following unilateral lesions of the cortex. With respect to the cells producing crossed projections, they were similar in both laminar and regional distributions between the intact and lesioned animal, suggesting that the crossed projections arise from the same neuronal subpopulation before and after cortical lesions. This view was supported by sequential injections of the tracers, which indicated that cells normally projecting contralaterally maintained the crossed projection after the lesions. Taking into account our previous observations that growth and proliferation of crossed corticorubral axons took place in the red nucleus (Murakami et al. 1991a), it is likely that growth and proliferation of the axons in denervated targets play a major role in lesion-induced establishment of aberrant projections. 相似文献
2.
Guo J Xiao B Zhang X Jin Z Chen J Qin L Mao X Shen G Chen H Liu Z 《Journal of molecular medicine (Berlin, Germany)》2004,82(11):768-774
To establish a novel molecular diagnostic method of detecting circulating tumor cells (CTCs) LS174T colon cancer cells were serially diluted with normal blood. Additional peripheral blood samples were collected from 25 patients with colorectal carcinoma. Mononuclear cells (MNCs) were collected, equally divided into four parts, and then cancer cells were enriched by four methods: method A, nonimmunobead method; method B, negative immunobead method: CD45 immunomagnetic beads were used to deplete the leukocytes; method C, positive immunobead method: Ber-EP4 immunomagnetic beads were used to enrich cancer cells; method D, negative-and-positive immunobead method: CD45 immunomagnetic beads were first used to deplete the leukocytes from MNC and then Ber-EP4 immunomagnetic beads were used to enrich cancer cells. Finally, real-time quantitative RT-PCR was used to monitor mRNA expression of 2-mircoglobulin (2M) and carcinoembryonic antigen (CEA). The relative CEA mRNA values were corrected with reference to 2M mRNA, to CEA mRNA/2M mRNA ratios according to a CEA mRNA external standards prepared with tenfold serial dilutions (1–104 IS174T cells) of cDNA and 2M mRNA external standards prepared with tenfold serial dilutions (102–107 leukocytes) of cDNA. In recovery experiments a significant correlation between the number of cancer cells and CEA mRNA expression was found when CD45 or Ber-EP4 immunomagnetic beads were used alone. A highly significant correlation was found when CD45 and Ber-EP4 immunomagnetic beads were used successively. The sensitivity of method D was one cancer cell per milliliter of blood. Circulating cancer cells were detected in 19 of 25 patients with colorectal cancers. The relative CEA mRNA value obtained by method D was the smallest. The positive detection rate of circulating cancer cells in patients at Dukes B, C, and D stages were 25.0% (1/4), 83.3% (10/12), and 88.9% (8/9). Combinative use of immunomagnetic isolation followed by real-time RT-PCR is a useful technique to detect circulating tumor cells in patients with colorectal carcinomas. Applying negative and positive immunomagnetic beads successively yields the highest correlation with amount of tumor cells. 相似文献
3.
A new method for histamine release from purified peripheral blood basophils using monoclonal antibody-coated magnetic beads 总被引:13,自引:0,他引:13
Nishi H Nishimura S Higashiura M Ikeya N Ohta H Tsuji T Nishimura M Ohnishi S Higashi H 《Journal of immunological methods》2000,240(1-2):39-46
A new method for evaluating histamine release from purified basophils was developed. Basophil-containing leukocytes were directly purified from a small amount of peripheral blood using monoclonal antibody BA312-coated magnetic beads. The purified basophils still rosetted to magnetic beads maintained a normal response to anti-IgE and to dust mite allergen in comparison with the conventional method using washed leukocytes. This methodology facilitates the purification of basophils, anti-IgE- and allergen-induced histamine release, and subsequent histamine determination within only 3 h. The released histamine was analyzed by an enzyme-linked immunosorbent assay (ELISA) with a characteristic detection profile. Since all steps were performed in 96-well microplates, many clinical samples could be analyzed at the same time, permitting easy applications in routine laboratories. 相似文献
4.
新近发展的在光纤芯片上做高通量测序的技术,可以将人类全基因组序列的测定时间由目前所用的10年时间缩短到100d。光纤芯片上的基因组测序结合了磁珠、乳液PCR和焦磷酸测序法等技术,利用光纤优良的表面性质和有效的加工工艺,将光纤制作成一种基因芯片。在芯片上用磁珠来耦联DNA、RNA等微量反应物。乳液PCR可以获得大量的不同的基因组DNA片段。乳液PCR和光纤芯片都是由于有了磁珠作为微量反应物的载体,从而可以将反应一再小型化。而这些技术的结合,工作效率是目前常规的测序方法的100多倍。成功实现了基因组测序反应小型化、高通量化的思想,大大降低了成本,减少了完成全基因组测序的时间。 相似文献
5.
目的 优选阿胶珠的炮制工艺。方法 采用L9(34)正交试验设计,以外观性状、水分、总灰分、特征多肽及氨基酸含量为指标,以炮制时间、炮制温度、每锅辅料用量为考察因素,结合直观分析、方差分析和熵权逼近理想解排序法(TOPSIS)对正交试验结果进行评价,优选阿胶珠炮制工艺,并进行炮制工艺验证。结果 优选的阿胶珠炮制工艺参数为炮制时间5 min、炮制温度190 ℃、蛤粉-阿胶为30∶1;验证实验中3批样品各指标的RSD为2.09%~4.91%。结论 优选的阿胶珠炮制工艺合理可行,可为阿胶珠工业化炮制生产提供参考。 相似文献
6.
载药微球经导管动脉化疗栓塞(DEB-TACE)利用微球在靶病灶内释放化学治疗(简称化疗)药物,使靶肿瘤内药物浓度更高,而全身化疗药物浓度及不良反应降低;且微球可较完全栓塞肿瘤毛细血管网,闭塞肿瘤邻近血管,致癌细胞缺血、缺氧而坏死。本文对DEB-TACE治疗肝细胞癌(HCC)研究进展进行综述。 相似文献
7.
免疫磁珠法分选胚胎大鼠脑神经干细胞的初步研究 总被引:11,自引:1,他引:10
目的:探索应用免疫磁珠间接阳性法分选神经上皮干细胞蛋白(nestin)阳性的神经干细胞群的实验条件,为研究神经干细胞的特性与神经干细胞的培养和移植研究创造有利条件。方法:制取胎鼠大脑组织细胞悬液,免疫磁珠法分选胎鼠脑神经干细胞,以流式细胞术检测阳性细胞纯度,以锥虫蓝染色法检测细胞活性。结果:该法分选的nestin阳性细胞纯度为93.0%~99.7%,其中活性细胞为92%~97%。结论:免疫磁珠法分离胎鼠脑神经干细胞群落简便、有效,可以为神经干细胞细胞培养和移植提供细胞来源,也为研究高纯度神经干细胞的特性提供了实验基础。 相似文献
8.
9.
海藻酸钙凝胶微球中模型药物的pH值依赖性释放 总被引:1,自引:1,他引:1
目的:考察海藻酸钙凝胶微球中模型药物的pH值依赖性释放.方法:以硝苯地平为模型药,采用滴制法制备了含药微球;考察了含药微球在不同pH值介质中的释放特性.结果:含药微球在水及pH 1.0的介质中几乎不溶胀,12 h累积释放百分率为23.1%和23.4%;在pH6.8的介质中微球溶胀至完全溶蚀,且呈现缓慢释放的趋势,12 h药物的累积释放百分率为92.5%;换介质的释放中,0~2 h微球几乎不溶胀,2 h累积释放8.4%,介质pH改变后微球很快崩解,3 h累积释放82.4%.结论:海藻酸钙凝胶微球中硝苯地平的释放具有pH值依赖性,在pH 6.8的介质中缓释. 相似文献
10.
Shqipdona Lahu Peter Bristot Senta Gewalt Alexander Goedel Daniele Giacoppo Stefanie Schüpke Heribert Schunkert Adnan Kastrati Nikolaus Sarafoff 《Journal of atherosclerosis and thrombosis》2022,29(7):1001
Aim: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an ongoing debate and novel data has emerged. The aim of this meta-analysis was to assess outcomes of short vs. control DAPT duration. In addition, the role of single antiplatelet therapy (SAPT) after DAPT with either aspirin or P2Y12 inhibitor monotherapy was analyzed. Methods: The authors searched MEDLINE and Cochrane databases and proceedings of international meetings for randomized controlled trials (RCT) comparing ≤ 3 months with ≥ 6 months DAPT after DES implantation. The primary and co-primary outcomes of interest were definite or probable stent thrombosis (ST) and bleeding. In addition, we performed an analysis on studies who continued with either aspirin or P2Y12 monotherapy after DAPT. Results: 9 RCTs comprising 41,864 patients were included and we analyzed a short DAPT duration of median 1.5 months vs. 12.1 months in the control group. The risk for ST was similar with short vs. control DAPT duration (0.5 vs. 0.5%; hazard ratio 1.17[95% CI 0.89-1.54];p=0.26). Bleeding was significantly reduced with short vs. control DAPT duration (1.9 vs. 3.0%; 0.65[0.54-0.77];p<0.0001). ST was not different between short vs. control DAPT duration in the analysis of the 4 RCTs who continued with aspirin after DAPT and the 5 P2Y12 RCTs, respectively, and no heterogeneity was detected (p=0.861). Bleeding was also reduced with short vs. control DAPT in both the aspirin (1.2 vs. 1.7%; 0.71[0.51-0.99];p=0.04) and P2Y12 inhibitor studies (2.1 vs. 3.4%; 0.62[0.47-0.80];p=0.0003) and no heterogeneity was detected (p=0.515). Conclusions: Our meta-analysis shows that short DAPT ≤ 3 months followed by SAPT reduces bleeding and is not associated with an increase in ST. The results were consistent within the aspirin and P2Y12 SAPT studies. 相似文献