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11.
Nerve growth factor-induced increase in calcium uptake by PC12 cells   总被引:1,自引:0,他引:1  
Treatment of PC12 cells with nerve growth factor (NGF) produces a rapid and transient increase in calcium uptake into the cells. The increased uptake is maximal after 5 minutes of NGF treatment, but after 15 minutes of NGF treatment, no such increase can be observed. The effect of NGF is partially inhibited by blockers of L-type calcium channels. K-252a, an alkaloid-like kinase inhibitor that usually is found to inhibit the actions of NGF on PC12 cells, produces an increase in calcium uptake similar to, but smaller than, that seen with NGF. NGF had no effect on calcium release under these conditions.  相似文献   
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第二足趾跖侧菱形皮瓣转移改形法再造拇指   总被引:5,自引:0,他引:5  
目的介绍第二足趾跖侧菱形皮瓣转移改形再造拇指的方法。方法用传统方法切取第二足趾后,于第二足趾近段跖侧设计菱形皮瓣,用180°逆形转移或向远侧直接推进的方法将皮瓣嵌入第二足趾跖侧狭细处,以改善其外形。结果临床应用6例,再造拇指全部存活。术后随访3~24个月,再造拇指外形美观,感觉运动恢复满意。结论用第二足趾跖侧菱形皮瓣转移改形法再造拇指,能明显改善第二足趾的外形,使再造拇指更美观。  相似文献   
14.
目的探讨第一、二鳃弓综合征面部不对称畸形的整形外科矫治方法。方法根据第一、二鳃弓综合征患者临床及X线所示面部双侧不对称情况,采用健侧下颌骨外板去除、颧骨截骨降低;患侧下颌体、颧骨应用健侧下颌骨外板贴附植骨或高密度多孔聚乙烯(Medpor)假体置入等术式,配合颏部水平截骨颏成形术,以缩小面部双侧宽度的差异,矫治颜面不对称畸形。结果共矫治23例,经6个月至3年的术后随访观察,双侧面部宽度差异明显缩小,正面观面部不对称明显改善。结论第一、二鳃弓综合征面部骨骼发育畸形是三维方向的,双侧面骨宽度的差异,是造成正面观面部不对称的重要因素,根据受术者的具体情况,采用以上术式的组合,扩充患侧或同时缩窄健侧骨骼,进行面部骨性支架重建,可以取得良好的矫治效果。  相似文献   
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Summary Cerebral primitive neuro-ectodermal tumour (PNET) occurring as a second primary malignancy in childhood is exceedingly rare. We present a 7-year-old boy who developed a proven supratentorial PNET five years after enucleation and radio-/chemotherapy for a sporadic, unilateral retinoblastoma with optic nerve invasion. The association with this malignant eye disease as well as the effect of irradiation and multi-agent chemotherapy on second tumour induction are evaluated.  相似文献   
17.
Abstract: We performed a retrospective analysis of clinical course of 91 patients who developed both breast cancer and a chronic lymphoproliferative neoplasm and were seen at the M. D. Anderson Cancer Center between January 1, 1970 and December 30, 1991. The sample included 24 individuals who developed lymphoproliferative neoplasm first (Group A), 22 individuals with concurrent diagnosis of both malignancies (Group B), and 45 individuals who developed breast cancer first (Group C). The median time to diagnosis of secondary breast cancer and lymphoproliferative neoplasm was 66 months (range, 7–459) and 65 months (range, 0–334), respectively. A higher proportion of Group B lymphomas were low-grade (77% vs. 47% [Group A] vs. 37% [Group C] p = 0.009). Prior occurrence of either one of these malignancies did not affect the disease-specific survival from the second malignancy. However, continuing mortality from the first malignancy appeared to contribute to a poor overall survival following second malignancy. Group A included 8 patients who developed breast cancer following radiation therapy for Hodgkin's disease after a mean interval of 18 (± 4.3) years. Three of these individuals had coexisting ductal and lobular histology (vs. none of the individuals in Groups B and C, p = 0.02). Another interesting finding was the high incidence of multiple additional malignancies in this patient population. A total of 29 additional neoplasms occurred in 21 (23%) of the 91 study subjects. These malignancies involved a wide variety of organ sites and could not be attributed to the therapy for either the breast cancer or the lymphoma in most cases. The data suggest that individuals who develop both breast cancer and a lymphoproliferative neoplasm are at a high risk for multiple malignancies. Close surveillance of such individuals for additional malignancies and further studies to understand the molecular basis of this predisposition are warranted.?  相似文献   
18.
对有机硒和无机硒的测定进行了探讨,利用压榨提取无机硒,用荧光二阶导数法进行硒的定量测定,通过标准添加法对提取率进行了测定,回收率为93.2%~98.4%,变异系数为1.86.  相似文献   
19.
依沙吖啶引产失败后用卡前列甲酯栓的疗效   总被引:2,自引:1,他引:1  
目的:观察35例中期妊娠用依沙吖啶1次羊膜腔注射引产失败后,再用卡前列甲酯栓的效果。方法:卡前列甲酯栓1mg,放置于阴道后穹窿,若3h后无宫缩,再放1次。结果:35例孕妇引产成功率100%。引产后24h内阴道流血量200±20mL。出现腹泻,恶心等不良反应各1例。结论:卡前列7甲酯栓用于对依沙吖啶中期引产失败后效果满意。  相似文献   
20.
BACKGROUND: The study was carried out to clarify the incidence of post-operative tubal adhesions, patency rate and pregnancy outcome after laparoscopic salpingotomy with and without suturing for tubal pregnancy. METHODS: From May 1996 to December 2002, a total of 97 cases of tubal pregnancy were treated in our centre by laparoscopic conservative surgery. The successful salpingotomy cases were randomly assigned to undergo salpingotomy without suturing (group I; n = 43) or with suturing (group II; n = 32). We compared these patients and assessed their surgical and pregnancy outcome by second look laparoscopy (SLL) 3 months after the first operation. RESULTS: Seventy-five cases (77%) were treated successfully by salpingotomy at initial laparoscopic surgery, and the remaining 22 cases were unsuccessful because of bleeding or complete tubal damage. Pelvic findings were assessed at SLL in 21 of 43 cases (49%) in group I and 17 of 32 (53%) in group II. There were no significant differences in gestational age, ectopic site, tubal diameter, tubal condition, intraperitoneal haemorrhage and pre-operative HCG levels between the two groups. Only the operation time was longer in group II than in group I (91 +/- 15 versus 69 +/- 15 min, P < 0.05). The tubal patency rate of the treated side was 90% (19/21) in group I and 94% (16/17) in group II. Also the peritubal adhesions were observed in 33% (7/21) in group I and 29% (5/17) in group II, and were mostly comprised of filmy adhesions. A tubal fistula occurred in two cases in each group. Pregnancy rate was 79% (15/19) in group I and 92% (12/13) in group II, and this did not reveal any significant difference of cumulative pregnancy rate between the groups. CONCLUSION: We recommend laparoscopic linear salpingotomy as a useful method in the management of cases with tubal pregnancy who desire future pregnancy. This preliminary study emphasizes that the procedure involving suturing has no additional benefit over the non-suturing technique during salpingotomy.  相似文献   
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