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81.
目的 评价核酸或核苷酸用于临床营养支持和免疫调节治疗的安全性、有效性和经济学价值。方法 检索中国生物医学文献数据库、Cochrane图书馆、MEDLINE光盘数据库、EMBASE光盘数据库,并联机检索SCI数据库,鉴定有关随机对照试验(RCTs),采用RevMan4.l进行Meta-分析。结果 纳入46个随机对照试验,涉及核酸/核苷酸用于肠内营养支持、婴儿营养、免疫调节治疗。18个研究报告了含核苷酸组分的免疫增强型肠内营养对外科术后和危重症患者预后的影响,合并分析发现免疫营养对患者感染率、住院时间和费用有肯定意义。发现1个报告在母乳代用品中加入核苷酸对婴儿免疫功能影响的研究,但报告对临床结局无明显影响。27个对“免疫核酸”用于免疫调节治疗的随机对照试验均为低质量研究,合并分析无法肯定iRNA的临床价值。结论 在外科术后患者应用免疫肠内营养制剂可降低感染率、缩短住院时间并可能减少住院费用,但不能确定作为组分之一的核苷酸的作用。尚无证据支持在母乳代用品中添加核苷酸具有临床意义。不能肯定免疫核酸是否具有免疫调节作用,亦未发现核酸在延缓衰老、改善老年人健康状况方面的可用证据。建议对核酸、核苷酸用于营养支持治疗和免疫调节治疗进行进一步研究,严格规范“核酸营养品”的宣传和应用。 相似文献
82.
牛磺酸对大鼠缺血心肌Bcl-2和Bax蛋白表达的影响 总被引:3,自引:0,他引:3
目的:探讨大鼠心肌缺血损伤与凋亡相关基因bcl-2和bax表达的关系及牛磺酸的影响。方法:结扎大鼠冠状动脉左前降支建立心肌缺血模型。检测心肌线粒体中超氧化物歧化酶(SOD)、Ca^2 -ATPase活性及MDA(丙二醛)含量,用免疫组化法检测Bcl-2和Bax蛋白在心肌中的表达量。结果:结扎冠脉左前降支可致心肌线粒体MDA含量升高,SOD和Ca^2 -ATPase活性下降;缺血心肌Bax蛋白表达呈显著升高;牛磺酸能明显减少缺血心肌线粒体MDA的生成,降低心肌Bax蛋白的表达,增加Bcl-2蛋白的表达。结论:结扎大鼠冠状动脉左前降支导致的心肌缺血损伤与Bcl-2和Bax蛋白的表达有关。 相似文献
83.
Ming Zhao Cheng Simon C F Rawlinson Andrew A Pitsillides Gul Zaman Subburaman Mohan David J Baylink Lance E Lanyon 《Journal of bone and mineral research》2002,17(4):593-602
The mechanism by which mechanical strain and estrogen stimulate bone cell proliferation was investigated using monolayer cultures of human osteoblastic TE85 cells and female human primary (first-passage) osteoblasts (fHOBs). Both cell types showed small but statistically significant dose-dependent increases in [3H]thymidine incorporation in response to 17beta-estradiol and to a single 10-minute period of uniaxial cyclic strain (1 Hz). In both cell types, the peak response to 17beta-estradiol occurred at 10(-8) - 10(-7) M and the peak response to strain occurred at 3500 microstrain ((mu)epsilon). Both strain-related and 17beta-estradiol-related increases in [3H]thymidine incorporation were abolished by the estrogen receptor (ER) modulator ICI 182,780 (10-8 M). Tamoxifen (10(-9) - 10(-8) M) increased [3H]thymidine incorporation in both cell types but had no effect on their response to strain. In TE85 cells, tamoxifen reduced the increase in [3H]thymidine incorporation associated with 17beta-estradiol to that of tamoxifen alone but had no such effect in fHOBs. In TE85 cells, strain increased medium concentrations of insulin-like growth factor (IGF) II but not IGF-I, whereas 17beta-estradiol increased medium concentrations of IGF-I but not IGF-II. Neutralizing monoclonal antibody (MNAb) to IGF-I (3 microg/ml) blocked the effects of 17beta-estradiol and exogenous truncated IGF-I (tIGF-I; 50 ng/ml) but not those of strain or tIGF-II (50 ng/ml). Neutralizing antibody to IGF-II (3 microg/ml) blocked the effects of strain and tIGF-II but not those of 17beta-estradiol or tIGF-I. MAb aIR-3 (100 ng/ml) to the IGF-I receptor blocked the effects on [3H]thymidine incorporation of strain, tIGF-II, 17beta-estradiol, and tIGF-I. HOBs and TE85 cells, act similarly to rat primary osteoblasts and ROS 17/2.8 cells in their dose-related proliferative responses to strain and 17beta-estradiol, both of which can be blocked by the ER modulator ICI 182,780. In TE85 cells (as in rat primaries and ROS 17/2.8 cells), the response to 17beta-estradiol is mediated by IGF-I, and the response to strain is mediated by IGF-II. Human cells differ from rat cells in that tamoxifen does not block their response to strain and reduces the response to 17beta-estradiol in TE85s but not primaries. In both human cell types (unlike rat cells) the effects of strain and IGF-II as well as estradiol and IGF-I can be blocked at the IGF-I receptor. 相似文献
84.
HCC的早期诊断是其治疗的关键,HCC血清标志物的检测又为其诊断提供了有利的途径,并且操作简单,敏感性高和特异性强。目前常用的血清标志物为AFP、AFP变异体、AFP mRNA、AFU、GGT、DCP、AIF、GPC3等。这些标志物的联合使用有助于HCC的诊断及预后。 相似文献
85.
目的:探讨甲状腺全切除术在治疗分化性甲状腺癌中的临床应用价值。方法:采用我院1988年1月~2001年5月甲状腺全切除术或甲状腺侧叶切除加峡部切除术治疗分化性甲状腺癌125例,对其手术并发症发生、局部复发、转移情况及术后5年生存率进行回顾性对比分析。结果:甲状腺全切除术术后并发症发生率高于甲状腺侧叶切除加峡部切除术组;局部复发、转移率低于侧叶切除加峡部切除术组;5年生存率两组无显著性差异。结论:甲状腺全切除术是治疗甲状腺癌有效的手术方式,但应掌握手术指征,改进、提高手术技术,减少并发症。 相似文献
86.
神经干细胞静脉移植治疗脊髓损伤的实验研究 总被引:3,自引:0,他引:3
[目的]观察神经干细胞静脉移植对损伤大鼠脊髓功能的治疗作用。[方法]取孕14—16dSD胎鼠的脑室下区组织,体外培养后鉴定细胞。制作脊髓全切模型,伤后1周将Brdu标记好的神经干细胞通过尾静脉注射移植到大鼠体内,移植后及8周行皮层体感诱发电位(CSEP)检测和BBB功能评分,并留损伤脊髓处作病理切片及免疫组化染色。[结果](1)移植后8周BBB评分损伤组、移植组都有所恢复,但都未达到正常水平,移植组恢复较好;(2)模型制作后,CSEP波均消失,细胞移植后8周移植组的波形有不同程度的恢复,但潜伏期延长;(3)移植组大鼠脊髓损伤处存在大量Brdu染色阳性细胞,表明移植的细胞在体内可到达损伤脊髓处并能存活;脊髓损伤部位NF-200及GFAP染色阳性的细胞表明移植的细胞可以分化为具有神经元和胶质细胞特性的细胞。[结论]静脉移植的神经干细胞能到达损伤区代替受损的神经元及神经胶质细胞,使损伤的脊髓功能得到一定程度的恢复。 相似文献
87.
Objective To test the hypothesis that p53 gene therapy combined with endostatin can enhance tumor response to radiation therapy of RM-1 mouse xenograft prostate cancer and to investigate its mechanism. Methods A mouse prostate cancer model was established. Then mice with xenograft tumor were randomly divided into group A (control), B (radiation), C (radiation and rAdp53), D (radiation and rh-endostatin) and E (radiation and rAdp53 and rh-endostatin). On day 1, rAdp53 was injected intra-tumorously with 1 × 1010 vp per animal to group C and E. From day 1 to 14, rh-endostatin was given 15 mg/kg intraperitoneally daily to group D and E. On day 4 single fraction of 15 Gy was given to tumors in groups B, C, D and E. Normal saline was injected intra-tumorously or intraperitoneaUy accordingly as control. No treatment was done to group A. Tumor volume was measured daily. Samples were collected on Days 5, 10 and 15. Ki67, CD31, p53 and VEGF were detected by means of immunohistochemistry. Results (1) Radiation alone, radiation combined with intra-tumorous injection of Adp53 and/or intraperitoneal injection of rh-endostatin resulted in tumor growth arrest of RM-1 cells in vivo (P = 0.000). Radiation combined with both rAdp53 and rh-endostatin was the most effective treatment (P < 0.05). (2) All the four treatment groups had a decreased expression of mutant type P53 (P = 0.000). The expression of Ki67 in groups B and C were equal (P 0.05) and increasing (P = 0.000), respectively. Group D had a up-down-up curve (P < 0.05), but group E had a up-down one. On day 5 the expresion of VEGF in group E was the lowest (P < 0.05). An increased expression of MVD compared with the control was shown, and MVD in groups C, D and E were always higher than that in the control (P < 0.05). Conclusions The limitation of radiotherapy could be overcome by combination with beth p53 gene therapy and endostatin on the growth of mouse prostate cancer cell. Radiation, rAdp53 and endostatin have their own role but they can be interacted with each other. 相似文献
88.
氟尿嘧啶化放疗的现状与未来 总被引:1,自引:0,他引:1
20世纪60年代在肿瘤的根治和辅助治疗中就使用了氟尿嘧啶(Fluorouracil,FU)化放疗(外放疗同时进行化疗)。2002年.全世界约200万肿瘤患者接受了FU治疗.其中很大一部分是以FU为基础的化放疗。FU是许多肿瘤患者的基础治疗药物。总之,FU化放疗显著改善了肿瘤的局部控制.并提高了部分肿瘤患者的生存率:也提高了部分具有重要功能的器官的保留。 相似文献
89.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献
90.
1学分制产生的背景 学分制是随着课程选修制的产生、发展而建立起来的教学管理制度.它产生于18~19世纪的欧美国家,于20世纪20年代经我国的一些教育家从日本或欧美引进. 相似文献