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991.
Jiange Qian MD Wenzhong Li PhD Guocheng Zhang MD Liangbin Yan MS Wei Sun PhD † 《Dermatologic surgery》2005,31(1):23-26
BACKGROUND: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment. OBJECTIVE: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods. MATERIALS AND METHODS: Cell cultures and transplant of hair follicle units into athymic mice were performed. RESULTS: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05). CONCLUSION: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours. 相似文献
992.
993.
高校学生职业指导宜及早进行 总被引:1,自引:0,他引:1
职业指导是一门指导人们了解职业、准备职业、选择职业、转换职业的科学,如何将职业指导贯穿于大学教育的全过程,各学校应根据不同学生给予具体指导,学生也应主动思考、自觉规划,大学阶段的职前生涯规划关系到职后人生发展,职业生涯及早规划才能赢得主动。 相似文献
994.
Mi Sook Gwak Kwang-Woong Lee Shi Yeon Kim Jihyun Lee Jae Won Joh Sung Joo Kim Hwan Hyo Lee Jean Wan Park Gaab Soo Kim Suk-Koo Lee 《Liver transplantation》2005,11(3):331-335
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings. 相似文献
995.
JC病毒样颗粒可直接转运进入细胞核 总被引:2,自引:1,他引:1
目的探讨JC病毒(JCV)病毒样颗粒(VLP)是否可以直接转运进入细胞核。方法心用JCV主要外壳蛋白VP1体外表达、重组VIP,在其表面标记异硫氰基荧光素(FTTC),同时在其内部包裹荧光染料Cy3,感染培养的HeLa细胞和SVG细胞,荧光显微镜观察VLP入核转运。结果HeLa和SVG细胞感染包裹Cy3的FTTC-VLP时,FTTC与Cy3同时出现于细胞核内相同部位;而感染FTTC—VP1与Cy3混合物时,FTTC虽可在细胞核内检测到,但Cy3信号几乎消失。包裹Cy3的VIP用SDSPAGE展开,荧光显像后行考马斯亮蓝(CBB)染色,发现Cy3和VLP移行至不同部位,证明Cy3不能与VP1结合,提示VLP以完整的颗粒形式转运进入细胞核。应用包裹外源性DNA的VLP感染培养的HeLa和SVG细胞,发现包裹的DNA在细胞浆和细胞核内均可检测到,提示JCV入核过程与VIP相同。结论VLP可以不经裂解直接转运进入细胞核,JCV入核转运可能与VLP相同。 相似文献
996.
997.
噬菌体抗体库固相筛选条件的初步研究 总被引:1,自引:1,他引:0
目的:探讨噬菌体抗体库的固相筛选条件,为筛选方案的设计提供实验依据。方法:利用多种针对HEVNE2蛋白的特异性噬菌体人源抗体和非特异性噬菌体人源抗体,对噬菌体抗体与抗原的结合时间、抗原包被的浓度、洗涤强度和洗脱方式等多种筛选的条件进行初步探索。结果:阳性噬菌体抗体与抗原反应1min,就可较好结合,洗涤次数为20~30次、洗涤液的pH为5时,筛选得到的阳性率最高。包被抗原的浓度对筛选的阳性率没有明显影响,用10mg/L抗原竞争洗脱60min,可得到较高的阳性率。结论:噬菌体抗体库的筛选是一个非常复杂的过程,其中的各个条件之间有着密切的联系,应该根据具体情况进行调整。 相似文献
998.
Chih-Yang Lin Wen-Jeng Lee Shyh-Jye Chen Ching-Hwa Tsai Jei-Han Lee Chia-Hung Chang Yu-Tai Ching 《Journal of digital imaging》2006,19(4):351-361
Computed radiography (CR) has many advantages such as filmless operations, efficiency, and convenience. Furthermore, it is
easier to integrate with the picture archiving and communication systems. Another important advantage is that CR images generally
have a wider dynamic range than conventional screen film. Unfortunately, grid artifacts and moiré pattern artifacts may be
present in CR images. These artifacts become a more serious problem when viewing CR images on a computer monitor when a clinic
grade monitor is not available. Images produced using a grid with higher frequency or a Potter–Bucky grid (i.e., a moving
grid, Bucky for short) can reduce occurrence but cannot guarantee elimination of these artifacts [CR & PACS (2000); Detrick
F (2001), pp 7–8]. In this paper, the formation of the artifacts is studied. We show that the grid artifacts occur in a narrow
band of frequency in the frequency domain. The frequency can be determined, accurately located, and thus removed from the
frequency domain. When comparing the results obtained from the proposed method against the results obtained using previous
computer methods, we show that our method can achieve better image quality. 相似文献
999.
1000.
本文报告65例双炔失碳酯配伍d1-15甲基PGF_(2α)(以下简称PG)抗早孕结果并与33例丙睾配伍PG抗早孕结果进行比较。结果显示,双炔失碳酯组完全流产59例,占90%;不全流产3例,占5%;失败3例,占5%;总有效率95%。丙睾组完全流产27例,占82%;不全流产6例,占18%;总有效率100%。两组总有效率无显著差异;完全流产率无显著差异;但不全流产率有明显差异(P<0.05)。药流后点滴出血天数,双炔失碳酯组平均为8.1±5.0天;丙睾组平均为18.9±19.1天;两组有明显差别(P<0.05)。双炔失碳酯经阴道给药后无一例发生心、肝、肾功能变化。 相似文献