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31.
Plasmids encoding foot-and-mouth disease virus VP1 epitopes elicited immune responses in mice and swine and protected swine against viral infection 总被引:20,自引:0,他引:20
VP1 is a capsid protein of foot-and-mouth disease virus (FMDV) and contains epitopes of the virus. Plasmids encoding two VP1 epitopes (amino acid residues 141-160 and 200-213) and a host-self immunoglobulin molecule were constructed to produce a new type of FMD DNA vaccine. Two plasmids, namely, pCEIM and pCEIS, containing mouse immunoglobulin (IgG) or swine IgG were subjected to immunogenicity testing in mice and swine, respectively. In mice administrated pCEIM in the abdomen using a genegun, both FMDV-specific T-cell proliferation and neutralizing antibodies were detected. In swine immunized with pCEIS at the back of the ear, immune responses were achieved after the second administration. Swine showed a T-cell proliferative response with a stimulation index (SI) of up to 8.1 and a neutralizing antibody response that was able to protect suckling mice from 10(2) LD(50) (lethal dose 50) FMDV challenge. To compare the immunogenicity of the DNA-based vaccine candidate, versus the protein-based vaccine candidates, a second group of swine was immunized with the protein F1-scIgG, which was encoded by the plasmid pCEIS. Injection with F1-scIgG elicited a T-cell proliferative response of SI < 1.7 and a neutralizing antibody response that protected suckling mice from up to 10(5) LD(50) FMDV challenge. In the challenge test, three of three swine immunized with pCEIS were fully protected from FMDV challenge. 相似文献
32.
护理人员应付方式的相关因素分析 总被引:9,自引:0,他引:9
目的 探讨影响护理人员应付方式的相关因素。方法 采用应付方式问卷和艾森克个性问卷对303名护理人员进行评定。结果 护理人员的应付方式与个性心理特征相关性较大,与年龄和护龄不呈线性关系,与是否倒班和不同的科室无关。4-5年和6-8年护龄的护理人员在应用解决问题应付方式上,比其他护龄组明显减少。结论 应加强护理人员,尤其是工作4-8年的护理人员的应付方式的指导。 相似文献
33.
目的观察健康青年人在等长收缩运动(IE)时血浆内啡肽(EOPs)的变化.方法选择健康自愿受试者40例,男女各20例,平均年龄(23.7±2.9)岁,研究设置二种模型即主观运动和被动运动.观察指标包括血浆中的亮氨酸脑啡肽(LEK)、β-内啡呔(β-END)和强啡呔(DYN).结果LEK、β-END、DYN在IE中均有不同程度的变化.结论在IE中LEK、DYN的变化程度较β-END明显(P<0.01). 相似文献
34.
Huan Cai Yu Jiang Sheng Zhang Ning-Ning Cai Wen-Qian Zhu Rui Yang Bo Tang Zi-Yi Li Xue-Ming Zhang 《Andrologia》2021,53(6):e14056
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm. 相似文献
35.
Tong Chen Jianglong Chen Qingfeng Sheng Linlin Zhu Xiaoling Bai Weijue Xu Jiangbin Liu Xiaoyan Li Zhibao Lv 《Journal of pediatric surgery》2021,56(4):800-804
BackgroundPyriform sinus fistula (PSF) is a rare congenital anomaly, and the preferred definitive treatment is yet to be verified. In this study, we investigated the treatment outcomes of PSF specifically comparing endoscopic-assisted surgery and endoscopic radiofrequency ablation (RA).MethodsThe medical records of patients treated for PSF at the Shanghai Children's Hospital between October 2016 and September 2019 were retrospectively evaluated.ResultsThere were 93 girls and 98 boys. The median age at onset and operation was 3 years and 5 years, respectively. Endoscopic-assisted surgery was performed in 143 patients. During the same period, RA was performed in 48 patients, and 10 of them concurrently underwent incision and drainage of neck abscesses. Longer hospital stay was found in the endoscopic-assisted surgery group than in the RA group (10.50 ± 3.93 vs. 5.02 ± 3.30 days, P < 0.001). Postoperative complications were not significantly different between the two groups, except for neck infection (0 vs. 8.3%, P = 0.004). After a median follow-up period of 21 months, no significant difference was found between the two groups in terms of recurrence (1.4% vs. 0, P = 0.560).ConclusionPatients treated with RA had a significantly shorter hospital stay than those treated with endoscopic-assisted surgery. Outcomes of endoscopic-assisted surgery and RA were not significantly different for the management of PSF and treatment method should be tailored to the patient.Level of evidenceIV. 相似文献
36.
目的:观察安脑片联合奥拉西坦治疗脑卒中后血管性痴呆(VD)热毒内盛证的临床疗效。方法:按随机数字表法将100例脑卒中后VD热毒内盛证患者分为治疗组与对照组,每组50例。对照组采用奥拉西坦治疗,治疗组给予安脑片联合奥拉西坦治疗,2组均治疗4周。比较2组临床疗效与不良反应发生率。采用美国国立卫生研究院卒中量表(NIHSS)、简易智能精神状态检查量表(MMSE)、临床痴呆评定量表(CDR)、日常生活活动能力量表(ADL)评估神经功能、认知功能、痴呆程度和日常生活活动能力;比较双侧大脑中动脉(MCA)、基底动脉(BA)、大脑前动脉(ACA)、椎动脉(VA)平均血流速度,以及血清脑源性神经营养因子(BDNF)、血管内皮生长因子(VEGF)水平。结果:治疗后,治疗组临床疗效总有效率96.00%,高于对照组82.00%(P<0.05)。治疗后,2组NIHSS、CDR评分均较治疗前降低(P<0.05),MMSE、ADL评分均较治疗前升高(P<0.05);治疗组NIHSS、CDR评分均低于对照组(P<0.05),MMSE、ADL评分均高于对照组(P<0.05)。治疗后,2组... 相似文献
37.
Xu Li Siming Li Zhihong Chi Chuanliang Cui Lu Si Xieqiao Yan Lili Mao Bin Lian Bixia Tang Xuan Wang Xue Bai Li Zhou Yan Kong Jie Dai Jun Guo Xinan Sheng 《Urologic oncology》2021,39(1):75.e1-75.e8
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC. 相似文献
38.
心脏直视手术患儿补体4基因多态性对体外循环中补体激活程度的影响 总被引:2,自引:0,他引:2
目的:研究补体4基因多态性与体外循环中补体系统激活程度和肺功能障碍之间的关系。方法:选择武汉市及周边地区在体外循环(CPB)下进行心脏直视手术的患儿156例,于术前抽血用交叉免疫电泳法进行补体4基因型分析。分别于CPB开始前,CPB结束时以及鱼精蛋白中和肝素后10min抽取动脉血样,以放免法对补体3和4活化产物C3a和C4a进行测定。同时记录肺顺应性。结果:补体4基因型AABB,AOBB,OOBB,AABO及AAOO出现频率分别为51.28%,17.95%,4.49%,19.87%及6.41%,CPB结束时C4a水平无明显升高,C3a水平显著升高。鱼精蛋白中和肝素后10min时C4a和C3a水平显著升高,以OOBB组升高最显著,其次为AOBB组;同时OOBB组肺顺应性下降最显著,其次为AOBB组,结论:体外循环由替代途径激活补体系统,鱼精蛋白-肝素复合物由经典途径激活补体系统,国人补体4基因型中,OOBB型出现的频率较白种人高,该基因型在体外循环中补体系统被激活及肺功能受损程度最严重。 相似文献
39.
Objective To observe the level of muscarinic receptors in airway and lung tissues, and the effect of inhaled ipratropium bromide on these receptors in a rat model of chronic obstructive pulmonary disease (COPD). Methods This model was developed by exposure of rats to 250 ppm SO2 gas, 5?h/d, 5d/wk, for a period of 7 wk. The COPD rats inhaled 0.025% aerosolized iratropium bromide for 20 min, 2 times daily, in an airtight chamber. Muscarinic receptors in airway and lung tissues of normal rats, ipratropium bromide-treated COPD rats and the recovering COPD rats were measured by the radio-ligand binding assay. Results Airway/lung pathology and pulmonary function tests showed that chronic SO2 exposure caused pathophysiologic changes similar to those observed in human COPD. The density (0.038±0.011, pmol/mg protein) and affinity (Kd, 23±11 pmol/L) of muscarinic receptors in airway and lung tissues of COPD rats were not changed compared with those of normal control rats (0.030±0.008 and 29±19, respectively, P>0.05). Densities of the muscarinic receptors were not changed after inhalation of ipratropium bromide for 5 days, but increased significantly after inhalation for 30 days, as compared with those of the untreated COPD rats. The muscarinic receptors returned the normal levels at day 6 after cessation of ipratropium bromide treatment. There were no differences among different groups of rats in equilibrium dissociation constants (Kd). Conclusion A rat model of COPD with pathophysiologic changes similar to the human counterpart was developed using chronic SO2 exposure. There was no significant change in the number and function of muscarinic receptors in airway and lung tissues of the COPD rats, but upregulation of the muscarinic receptors was observed after long-term inhalation of ipratropium bromide. 相似文献
40.
目的:探讨原发性女性生殖器恶性黑色素瘤的临床病理特点及合理的治疗方法。方法:对16例原发性女性生殖器恶性黑色素瘤的临床资料进行回顾性分析。结果:发生于外阴9例,阴道5例,子宫颈2例。全部病例均行手术加化疗综合治疗,行区域淋巴结清扫11例,4例有转移,转移率36.3%。存活<2年8例,≥2年8例,其中≥5年仅2例。结论:原发性女性生殖器恶性黑色素瘤预后差,行根治手术辅化疗和免疫治疗,可望提高生存期。 相似文献