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991.
通过RT-PCR克隆到含有全部编码序列的人IL-2 cDNA,并经核苷酸测序加以证实。将其克隆至逆转录病毒载体pLXSN,构建成人IL-2的重组逆转录病毒表达载体pLXSN-hIL2,体外经CRIP细胞包装后病毒滴度达7.6×10~5CFU/ml。NIH3T3小鼠成纤维细胞感染hIL-2重组逆转录病毒后,分泌IL-2水平达118.2U/ml;PCR从其基因组DNA中扩增到NeoR基因片段,提示重组逆转录病毒载体己整合至宿主细胞的基因组DNA中。本研究为开展人IL-2基因治疗奠定了基础。 相似文献
992.
fat-1基因对乳腺癌细胞的增殖抑制作用 总被引:1,自引:0,他引:1
目的: 以胃癌特异性多肽抗原MG7为靶点研制胃癌特异性纳米疫苗,并观察其对小鼠的免疫效能.方法: 人工合成胃癌MG7-Ag的模拟表位多肽,用磁力超声法将其包封于纳米乳剂中,通过透析纯化,HPLC检测其包封效率.用包封有MG7抗原肽的纳米疫苗免疫健康Balb/c小鼠,以空白纳米疫苗和PBS作为对照,测定其免疫活性,通过ELISA测定血清中抗MG7抗体的效价;ELISPOT测定小鼠脾CTL活性.同时,用表达MG7-Ag的小鼠艾氏腹水瘤细胞进行肿瘤攻击2周,观察疫苗对小鼠的保护作用.结果: 成功制备了胃癌MG7-Ag的纳米疫苗,并具有较好的包封率和较好的稳定性,小鼠产生MG7抗体, ELISPOT检测包封组与对照组相比分泌IFN-γ的活性淋巴细胞数量明显增高.疫苗免疫组8只小鼠中有2只未见肿瘤形成, 而对照组8只小鼠则全部成瘤.结论: 胃癌MG7-Ag表位纳米疫苗具有免疫原性,可以诱导小鼠产生抗肿瘤免疫. 相似文献
993.
目的 研究NSCLC的SRT中基于四维CT不同ITV合成策略的几何差异性。方法对我院2013—2014年间收治的16例具有胸部SRT指征的NSCLC患者行4DCT扫描, 比较目前基于全时相勾画合成(金标准)得到的IGTV10、EE或EI时相合成得到的IGTVEI+EE、MIP重建序列MIP勾画合成得到的IGTVMIP、AVG重建时相勾画方法得到的IGTVAVG, 韩国顺天乡大学4个时相确定IGTVyeo, 以及我们提出的基于奇数或偶数时相勾画合成的IGTVODD、IGTVEVEN方法同IGTV10的MI、DI和体积差异, 分析筛选出对肿瘤运动相关特性相对不敏感的ITV合成方法。组内、组间数据行Student-Newman-Keulsa检验, 同时用多参数回归分析肿瘤三维运动量、肿瘤体积和MI和DI相关性。结果 患者肿瘤中心平均三维运动幅度1.23 cm (0.25~5.53 cm), 三维运动矢量分别为左右3.5 mm (1.4~8.4 mm), 前后4.5 mm (1.1~8.6 mm), 上下9.5 mm (0~10 mm)。IGTVMIP、IGTVAVG、IGTVEI+EE、IGTVyeo 、IGTVODD、IGTVEVEN、IGTV10之间平均MI分别为0.69、0.62、0.80、0.86、0.93、0.91(P=0.006);平均DI分别为0.98、0.98、0.97、0.97、0.99、0.98(P=0.130), IGTVx体积相比IGTV10分别偏小25.7%、35.6%、17.9%、12.8%、3.6%、4.8%(P=0.000)。通过回归分析得到肿瘤大小、肿瘤运动幅度不是基于奇数或偶数时相形成ITV的影响因素。结论 基于奇数或偶数时相确定ITV方法对肿瘤所在位置及肿瘤运动幅度等因素不敏感, 具有较好临床可靠性和较高勾画效率, 在无弹性形变配准的放疗单位可作为胸部SRT靶区勾画推荐方法。 相似文献
994.
Wenyuan Duan Yanlin Li Yeming He Duqiang Xin Najeeb ur Rehman Lashari Cheng Ma Yuzhen Zhao Zongcheng Miao 《RSC advances》2022,12(34):22244
Aqueous rechargeable lithium-ion batteries (ARLBs) are regarded as a competitive challenger for large-scale energy storage systems because of their high safety, modest cost, and green nature. A kind of modified composite material composed of H2V3O8 nanorods and graphene sheets (HVO/G) has been effectively made by a one-step hydrothermal method and following calcination at 523 K. XRD, SEM, TEM, and TG are used to determine the phase structures and morphologies of the composite materials. Owing to the advantage of the layered structure of H2V3O8 nanorods, the excellent conductivity of the graphene sheets, and the 3D network structure of the modified composite, the ARLBs with HVO/G can deliver an adequate specific capacity of 271 mA h g−1 at 200 mA g−1 and have a retention rate of 73.4% after 50 cycles. The average discharge capacity of ARLB with HVO/G as anode has a considerable improvement over that of HVO/CNTs and HVO, whatever the current rate used. Moreover, we find that the diffusion coefficient of lithium-ion increases by an order of magnitude through the theoretical calculation for HVO/G ARLB. The new ARLB with HVO/G electrode is a potential energy storage system with great advantages, such as simple preparation, easy assembly process, excellent safety and low-cost environmental protection.Aqueous rechargeable lithium-ion batteries (ARLBs) are regarded as a competitive challenger for large-scale energy storage systems because of their high safety, modest cost, and green nature. 相似文献
995.
目的:研究阿霉素联合hepaCAM基因对肾癌细胞786-0生物学的影响。方法:阿霉素处理后,用腺病毒向肾癌786-0导入肝细胞黏附分子(Hepatocyte cell adhesion molecule,hepaCAM),以噻唑蓝(Methyl thiazolyl tetrazolium,MTT)测抑制率,流式细胞术(Flow cytometer,FCM)测细胞周期,实时荧光定量聚合酶链反应(Real time quantitative polymerase chain reaction,RT-qPCR)、Western blot检测hepaCAM和细胞分裂周期基因2(Cell division cycle 2,cdc2)的mRNA及蛋白水平。结果:MTT显示:与对照组相比,实验组抑制率显著升高(P<0.01)。FCM证实:实验组出现明显G2/M期阻滞。RT-qPCR及Western blot检测到实验组cdc2 mRNA及蛋白水平显著下调(P<0.01)。结论:阿霉素处理后,导入hepaCAM基因,可引起细胞抑制率显著升高及G2/M期阻滞,这可能与阿霉素诱导hepaCAM下调cdc2的表达有关。 相似文献
996.
BackgroundTalus fractures are rare in children but can lead to severe outcomes if untreated. The Ilizarov external fixator has been used in the treatment of a variety of lower extremity pathologies. The purpose of this study was to investigate the clinical outcomes of talus body fractures treated with the Ilizarov external fixator.Case PresentationFour male pediatric patients (age range, 5–11 years) with talus body fractures who were treated by open reduction and internal fixation combined with Ilizarov external fixator between November 2015 and April 2016 were reviewed. Mean follow‐up period was 4 years (range, 4–5). Clinical outcome was evaluated using the clinical rating scale of the American Orthopaedic Foot and Ankle Society (AOFAS). All four patients achieved good to excellent results at the last follow‐up. None of the patients developed avascular necrosis. One patient developed automatic fusion of tibiotalar joint.ConclusionUse of the Ilizarov external fixator to gain early range of motion is a valuable option for treatment of talus body fractures in children. 相似文献
997.
XiangNan Zhang Wei Deng JiHui Ju Songqiang Zhang HongYu Wang KaiLong Geng DingSong Wang GuangLiang Zhang YingYing Le RuiXing Hou 《Orthopaedic Surgery》2022,14(8):1864
ObjectiveTo describe a method to display the three‐dimensional distribution of intraosseous arteries in the femoral head by vascular corrosion casting.MethodsAn experimental study was done to expose the intraosseous arteries of the femoral head by a microperfusion corrosion method between January 2021 and May 2021. Specimens were 23 swine femoral heads (12 female specimens and 11 male specimens, where age of swine ranged from 8 to 12 months, and the weight was approximately 150 kg). The femoral heads were microperfused with the vascular casting resin through retinacular arteries, and the bone of the femoral head was dissolved with 50% sodium hydroxide and 10% hydrochloric acid and rinsed under the microscope until the vessel casts were completely exposed. The distribution and anastomosis of the arteries in the femoral head were observed under direct vision and microscopy. The diameter of the artery in the femoral head was measured at 0.5 cm after its entry into the bone of the femoral head with a microscale under the microscope. The number of internal arteries with diameter ≥0.05 mm was counted. The number and diameter of the main trunk of the epiphyseal arteries in the femoral head between male and female swine were compared.ResultsThe vascular casting specimen of the swine femoral head was successfully produced by using epoxy resin as a casting agent, and the three‐dimensional intraosseous vascular structures were clearly visible. The number of epiphyseal arteries in male and female swine was 8.55 ± 2.15 and 8.83 ± 2.15 (t = −0.31, p = 0.38), respectively. The diameters of the superior epiphyseal arteries in male and female swine were 0.35 ± 0.09 and 0.31 ± 0.08 mm (t = 1.03, p = 0.16), the diameters of the inferior epiphyseal arteries were 0.47 ± 0.05 and 0.49 ± 0.09 mm (t = −0.57, p = 0.29), and the diameters of the anterior epiphyseal arteries were 0.34 ± 0.08 and 0.33 ± 0.13 mm (t = 0.32, p = 0.37). There was no significant difference in the number and diameter of the main trunk of intraosseous arteries between male and female swine (p > 0.05). The main trunk of intraosseous arteries formed an anastomosis in the center of the femoral head. Among 23 swine femoral head samples, three types of intraosseous anastomosis were observed, including 13 (57%) posterior superior‐posterior inferior, seven (30%) posterior inferior‐anterior, and three (13%) uniform intraosseous anastomosis.ConclusionThe microperfusion corrosion method can produce the vascular casting specimen of swine femoral head revealing the three‐dimensional structure of the intraosseous artery, which clearly shows the origin, course and branches, and diameter, as well as the anastomosis, of nutrient arteries in the femoral head. This method provides a simple and rapid technique for quantifying and visualizing intraosseous arteries. 相似文献
998.
Yuhui Deng Jisheng Li Hui Xu Ahong Ren Zhenchang Wang Dawei Yang Zhenghan Yang 《临床与转化肝病杂志(英文版)》2022,10(4):642
Background and AimsMicrovascular invasion (MVI) is a major risk factor for the early recurrence of hepatocellular carcinoma (HCC) and it seriously worsens the prognosis. Accurate preoperative evaluation of the presence of MVI could greatly benefit the treatment management and prognosis prediction of HCC patients. The study aim was to evaluate the diagnostic performance of the apparent diffusion coefficient (ADC), a quantitative parameter for the preoperative diagnosis MVI in HCC patients.MethodsOriginal articles about diffusion-weighted imaging (DWI) and/or intravoxel incoherent motion (IVIM) conducted on a 3.0 or 1.5 Tesla magnetic resonance imaging (MRI) system indexed through January 17, 2021were collected from MEDLINE/PubMed, Web of Science, EMBASE, and the Cochrane Library. Methodological quality was evaluated using Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). The pooled sensitivity, specificity, and summary area under the receiver operating characteristic curve (AUROC) were calculated, and meta-regression analysis was performed using a bivariate random effects model through a meta-analysis.ResultsNine original articles with a total of 988 HCCs were included. Most studies had low bias risk and minimal applicability concerns. The pooled sensitivity, specificity and AUROC of the ADC value were 73%, 70%, and 0.78, respectively. The time interval between the index test and the reference standard was identified as a possible source of heterogeneity by subgroup meta-regression analysis.ConclusionsMeta-analysis showed that the ADC value had moderate accuracy for predicting MVI in HCC. The time interval accounted for the heterogeneity. 相似文献
999.
目的:探讨翼状胬肉切除联合自体角膜干细胞移植术后巩膜融解的原因及处理方法。方法:回顾性分析276例2001年3月至2006年8月在我院行翼状胬肉切除联合自体角膜干细胞移植术治疗原发性翼状胬肉患者,术后有7例(2.54%)术区巩膜出现融解坏死,取坏死组织涂片、微生物培养及病理检查,并对7例患者进行血清学检查。1例融解范围大者行带蒂球结膜瓣转位移植,修补将要穿孔处。7例采用贝复舒眼药水点眼并泰利必妥眼膏包眼,每天换药,持续3-5 d。待有血管长入术区巩膜时改为环孢霉素A眼水点眼4次/d。结果:7例患者细菌及真菌培养均未见微生物生长,病理检查:7例均未见白细胞浸润。1例修补术后及另外6例均恢复良好,眼球运动正常,视力同未行胬肉切除术前时视力。随访12-24月,7例术区外观无异常变化。结论:手术因素造成的局部损伤缺血及诱发的免疫反应等可能是自体角膜干细胞移植术后巩膜融解的因素。 相似文献
1000.
苄胺唑啉加间羟胺联合细辛脑治疗小儿支气管肺炎80例临床疗效分析 总被引:1,自引:0,他引:1
目的:观察苄胺唑啉加间羟胺联合细辛脑佐治小儿支气管肺炎的疗效。方法:将住院170例支气管肺炎患儿按住院单双号分为观察组80例和对照组90例。对照组给予常规治疗,治疗组在常规治疗的基础上加用苄胺唑啉加间羟胺联合细辛脑静滴。比较2组治疗前后症状的缓解,肺部湿罗音变化和治愈率的情况。结果:治疗组加用苄胺唑啉加间羟胺联合细辛脑静脉滴注与对照组疗效比较,差异有非常显著性意义(P〈0.01)。结论:苄胺唑啉加间羟胺联合细辛脑静脉滴注治疗小儿支气管肺炎的疗效显著,值得在临床上推广。 相似文献