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81.
人内质网分子伴侣BiP的克隆、表达及其在RA患者血清抗体检测中的作用 总被引:1,自引:0,他引:1
以类风湿关节炎(rheumatoid arthritis,RA)患者滑膜组织文库cDNA为模板,用PCR方法扩增得到1965 bp人内质网分子伴侣BiP的全长cDNA,将其克隆入OmicsLinkTM表达载体pReceiver-B01a,构建重组表达质粒pReceiver-B01a-BiP。重组表达质粒导入大肠杆菌BL-21(DE3)菌株中诱导表达目的蛋白,表达产物以Ni+-NTA agarose层析柱纯化。SDS-PAGE和免疫印迹法(Western blot)分析发现,表达产物以可溶性蛋白和包涵体形式共同存在,表达量约占菌体蛋白总量的20%~30%。相对分子质量约为80000,纯度达到电泳级。经免疫印迹法鉴定,获得的BiP重组蛋白可以与RA患者血清反应,检测的抗BiP抗体在RA患者血清中的阳性率为75.4%(49/65),明显高于系统性红斑狼疮(systemic lupus erythe-matosus,SLE)患者14.6%(7/48)、原发性干燥综合征(primary Sj gren’s syndrome,pSS)患者7.3%(4/55)及正常人0%(0/71)(P<0.01)。表明,经原核表达获得的BiP全长蛋白,RA患者血清抗体可以很好结合,有望应用于临床血清学诊断。 相似文献
82.
83.
目的目前,国内所有大鼠腹部异位心脏移植均沿袭了Corry的传统的移植心脏血流循环构建模式,但其操作难度限制了其广泛应用,尝试一种新型的、更简介高效的心脏移植循环重建新技术。方法本方法利用大鼠供体大鼠肝脏以上下腔静脉代替肺动脉与受体肾以下腔静脉吻合。结果新方法双血管缝合时间为(30.5±2.1)min,明显短于传统血管吻合方法(39.7±3.6)min,术后心脏复跳时间也由原来的(1.9±0.4)min缩短到(1.1±0.2)min。结论新循环重建技术降低了大鼠心脏移植难度,缩短了移植心脏缺血和复跳时间。 相似文献
84.
Background: Malnutrition is associated with poor outcomes after stroke. However, the association between malnutrition and post-stroke depression (PSD) remains unelucidated. We aimed to explore the association between geriatric nutritional risk index (GNRI) and depression after ischemic stroke. Methods: In total, 344 patients with ischemic stroke were included in this analysis. The GNRI was calculated from serum albumin level, weight, and height at admission. Malnutrition was defined using the GNRI cutoff points. A lower GNRI score indicates an elevated nutritional risk. The outcome was depression, measured 14 days after ischemic stroke. Logistic regression models were used to estimate the association between the GNRI and risk of PSD. Results: A total of 22.9% developed PSD 14 days after stroke. The mean GNRI was 99.3 ± 6.0, and 53.8% of the patients had malnutrition. After adjusting for covariates, baseline malnutrition was not associated with risk of PSD (OR, 0.670; 95%CI, 0.370–1.213; p = 0.186). The restricted cubic splines revealed a U-shaped association between the GNRI and PSD. Compared to moderate GNRI, higher GNRI (OR, 2.368; 95%CI, 0.983–5.701; p = 0.085) or lower GNRI (OR, 2.226; 95%CI, 0.890–5.563; p = 0.087) did not significantly increase the risk of PSD. Conclusion: A low GNRI was not associated with an increased risk of depression after ischemic stroke. 相似文献
85.
This work was mainly focused on the processing-parameter-related microstructure and properties of ultrafine WC-10Co-0.4VC-0.5Cr3C2 cemented carbide. The samples were prepared via a spark plasma sintering (SPS) technique using nano WC and Co powders and the corresponding inhibitor VC and Cr3C2 powders. The influence of the processing process on the microstructure and mechanical properties of ultrafine-grained cemented carbide was investigated under different ball-milling times and sintering temperatures. The results showed that the grain size of WC decreased with increasing ball-milling time and decreasing sintering temperature and that the specific gravity of ε-Co increased with increasing ball-milling time. The hardness of cemented carbide increased with increasing ball-milling time and decreased with increasing sintering temperature due to the corresponding variation in grain size and the relative density of samples. The transverse fracture strength (TRS) was mainly affected by ball-milling time. The increase in ball-milling time led to decreased TRS values, mainly ascribed to the formation of WC particle agglomeration and the decreased WC-Co eutectic temperature. In addition, temperature changes were found to have little effect on TRS. The samples sintered at 1250 °C with a ball-milling time of 60 h had comprehensive mechanical properties. Their average grain size, relative density, hardness, and TRS were 355.5 nm, 95.79%, 2035.5 kg/mm2, and 2155.99 MPa, respectively. 相似文献
86.
Huabin Luo Bei Wu Angela R. Kamer Samrachana Adhikari Frank Sloan Brenda L. Plassman Chenxin Tan Xiang Qi Mark D. Schwartz 《International dental journal》2022,72(4):484
IntroductionThe aim of this research was to assess the association between inflammation and oral health and diabetes, as well as the mediating role of oral hygiene practice in this association.MethodsData were from the 2009–2010 National Health and Nutrition Examination Survey. The analytical sample consisted of 2,191 respondents aged 50 and older. Poor oral health was clinically defined by significant tooth loss (STL) and periodontal disease (PD). Diabetes mellitus (DM) was determined by glycemic levels. The outcome variable was serum C-reactive protein (CRP) level, dichotomised as ≥1 mg/dL (elevated CRP) vs <1 mg/dL (not elevated CRP). Two path models, one using STL and DM as the independent variable, the other using PD and DM as the independent variable, were estimated to assess the direct effects of having poor oral health and DM on elevated CRP and the mediating effects of dental flossing.ResultsIn path model 1, individuals having both STL and DM (adjusted odds ratio [AOR], 1.92; 95% confidence interval [CI], 1.30–2.82) or having STL alone (AOR, 2.30; 95% CI, 1.68–3.15) were more likely to have elevated CRP than those with neither STL nor DM; dental flossing (AOR, 0.92, 95% CI, 0.88–0.96) was associated with lower risk of elevated CRP. In path model 2, no significant association was found between having both PD and DM and elevated CRP; dental flossing (AOR, 0.91; 95% CI:, 0.86–0.94) was associated with lower risk of elevated CRP.ConclusionsFindings from this study highlight the importance of improving oral health and oral hygiene practice to mitigate inflammation. Further research is needed to assess the longer-term effects of reducing inflammation.Key words: Tooth loss, Periodontal disease, Diabetes, Inflammation 相似文献
87.
Xuan Han WuHu Zhang HeLi Gao TianJiao Li HuaXiang Xu Hao Li PengCheng Li Xu Wang XianJun Yu WenQuan Wang Liang Liu 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundThe selective pressure imposed by chemotherapy creates a barrier to tumor eradication and an opportunity for metastasis and recurrence. As a newly discovered stemness marker of pancreatic ductal adenocarcinoma (PDAC), the impact of CD9 on tumor progression and patient''s prognosis remain controversial.MethodsA total of 179 and 211 PDAC patients who underwent surgical resection with or without neoadjuvant chemotherapy, respectively, were recruited for immunohistochemical analyses of CD9 expression in both tumor and stromal areas prior to statistical analyses to determine the prognostic impact and predictive accuracy of CD9.ResultsThe relationship between CD9 and prognostic indicators was not significant in the non‐neoadjuvant group. Nevertheless, CD9 expression in both tumor (T‐CD9) and stromal areas (S‐CD9) was significantly correlated with the clinicopathological features in the neoadjuvant group. High levels of T‐CD9 were significantly associated with worse OS (p = 0.005) and RFS (p = 0.007), while positive S‐CD9 showed the opposite results (OS: p = 0.024; RFS: p = 0.008). Cox regression analyses identified CD9 in both areas as an independent prognostic factor. The T&S‐CD9 risk‐level system was used to stratify patients with different survival levels. The combination of T&S‐CD9 risk level and TNM stage were accurate predictors of OS (C‐index: 0.676; AIC: 512.51) and RFS (C‐index: 0.680; AIC: 519.53). The calibration curve of the nomogram composed of the combined parameters showed excellent predictive consistency for 1‐year RFS. These results were verified using a validation cohort.ConclusionNeoadjuvant chemotherapy endows CD9 with a significant prognostic value that differs between tumor and stromal areas in patients with pancreatic cancer. 相似文献
88.
骨整合义耳修复创伤性全耳廓缺损 总被引:2,自引:0,他引:2
目的探讨骨整合义耳修复创伤性全耳廓缺损的可行性和临床效果。方法回顾性分析19例创伤性全耳廓缺损采用骨整合义耳修复患者。其中先天性小耳畸形全耳再造失败者12例,硫酸烧伤1例,高温铝水烫伤1例,车祸所致4例,刀砍伤1例。所有病例得到随诊,时间3~5年。结果所有患者均1次治愈,有一个形态逼真、色泽自然的外观,用骨整合方法固位的义耳配戴稳定,对日常生活无影响。结论骨整合义耳修复方法简便、创伤小、治疗周期短,无并发症,效果满意。对全耳再造失败者是一有效的治疗补救,对耳廓连同周围组织大面积缺损后瘢痕愈合者是可优先选择的方法。 相似文献
89.
Guode Luo Qin Xiang Xiaohua Wang Yajiao Li Yongkuan Cao Jiaqing Gong Yunming Li 《The Journal of international medical research》2022,50(7)
ObjectiveTo compare the results and 5- and 8-year overall survival (OS) and disease-free survival (DFS) of hand-assisted laparoscopic surgery (HALS) and laparoscopic-assisted surgery (LAS) in radical gastrectomy for advanced distal gastric cancer.MethodsA total of 124 patients admitted to our institution from May 2009 to April 2013 were randomly divided into a HALS group (n = 62) and a LAS group (n = 62). Postoperatively, 110 patients were followed for 5 and 8 years, and 14 patients were lost to follow-up. The 5- and 8-year OS and DFS rates of the groups were compared and analyzed.ResultsThe 5- and 8-year OS rates, respectively, were 38.8% and 19.4% in the HALS group and 38.3% and 15.3% in the LAS group (log-rank test, χ2 = 0.250). The 5- and 8-year DFS rates, respectively, were 23.1% and 10.6% in the HALS group and 19.3% and 11.6% in the LAS group (log-rank test, χ2 = 0.109). No significant differences were found.ConclusionCompared with LAS, HALS radical gastrectomy for advanced distal gastric cancer had a lower conversion rate to open surgery, shorter surgical duration, and more thorough dissection of lymph nodes; 5- and 8-year OS and DFS rates were similar to those with LAS. 相似文献
90.
Chengwei Xiang Zekun Yang Ting Xiong Ting Wang Jie Yang Mei Huang Dingxiang Liu Ruiai Chen 《Viruses》2022,14(7)
Avian interferon regulatory factors 1 and 7 (IRF1 and IRF7) play important roles in the host’s innate immunity against viral infection. Our previous study revealed that duck tembusu virus (DTMUV) infection of chicken fibroblasts (DF1) and duck embryo fibroblasts (DEFs) induced the expression of a variety of IFN-stimulated genes (ISGs), including VIPERIN, IFIT5, CMPK2, IRF1, and IRF7. IRF1 was further shown to play a significant role in regulating the up-expression of VIPERIN, IFIT5, and CMPK2 and inhibiting DTMUV replication. In this study, we confirm, through overexpression and knockout approaches, that both IRF1 and IRF7 inhibit DTMUV replication, mainly via regulation of type I IFN expression, as well as the induction of IRF1, VIPERIN, IFIT5, CMPK2, and MX1. In addition, IRF1 directly promoted the expression of VIPERIN and CMPK2 in an IFN-independent manner when IRF7 and type I IFN signaling were undermined. We also found that non-structural protein 2B (NS2B) of DTMUV was able to inhibit the induction of IFN-β mRNA triggered by Newcastle disease virus (NDV) infection or poly(I:C) treatment, revealing a strategy employed by DTMUV to evade host’s immunosurveillance. This study demonstrates that avian IRF7 and IRF1 play distinct roles in the regulation of type I IFN response during DTMUV infection. 相似文献