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51.
以过硫酸胺为引发剂,在PVA水溶液中原位聚合丙烯酸单体,得到的PVA/PAA混合水溶液在凝固浴硫酸胺饱和水溶液中纺丝制备了物理缠结和氢固定网络形式的PVA/PAA水凝胶纤维。该纤维于NaCl溶液中在直流电场作用下具有电流-刺激敏感性,表现为溶胀、收缩、弯曲行为。纤维的弯曲速度和最大弯曲度随电场强度和凝胶网络中PAA含量的增加而增大,随电解质溶液离子强度的变化出现临界最大值。纤维向负极弯曲的过程中,在电场下自由离子和反庆子迁移引起的渗透压主导作用,弯曲过程主要是溶胀弯曲;向正极弯曲过程中,由于电化学反应和电场作用下产生的PH梯度导致凝胶网络构像变化主导作用,弯曲主要是收缩弯曲;弯曲由负极向正极转化过程中,两种机理对弯曲的影响相对平衡。  相似文献   
52.
目的 :评价中间型人工肝支持系统治疗重型肝炎的疗效。方法 :对 138例重型肝炎患者进行血浆置换联合胎肝细胞悬液治疗 ,5 6例重型肝炎患者采用血浆置换治疗 ,另 48例重型肝炎患者采用胎肝细胞悬液治疗。观察血浆置换联合胎肝细胞悬液治疗患者治疗前后肝功能、氨基酸谱及心肌酶学变化。比较血浆置换联合胎肝细胞悬液治疗与单用血浆置换或胎肝细胞悬液治疗的疗效。结果 :血浆置换联合胎肝细胞悬液治疗较单用血浆置换或胎肝细胞悬液治疗能更有效提高重型肝炎患者好转存活率 ,改善肝功能 ,提高支链氨基酸 (BCAA) /芳香氨基酸 (AAA)比值 ,改善心肌酶学。结论 :血浆置换联合胎肝细胞悬液可有效治疗重型肝炎。  相似文献   
53.
To evaluate the safety and efficacy of Chinese medicine, Qiaoshao formula combined with dapoxetine was used for the treatment of premature ejaculation in a real-life setting. Nine hundred and five males diagnosed with premature ejaculation were reviewed in this retrospective cohort study. We divided the patients into two groups: dapoxetine alone and Qiaoshao formula combined with dapoxetine according to actual interventions provided to patients in clinics. The perceived intravaginal ejaculation latency time and the premature ejaculation profile measures markedly improved in both groups. However, in men with severe premature ejaculation (baseline perceived intravaginal ejaculation latency time <1 min) and those with baseline age ≤30 years, the perceived intravaginal ejaculation latency time was slightly but significantly longer with combined therapy than with dapoxetine alone (p < .05). Therefore, combined therapy involving the Qiaoshao formula and dapoxetine proved to safe as well as effective for treating premature ejaculation while prolonging the perceived intravaginal ejaculation latency time, which significantly improved the overall satisfaction of the patient and likely that of the couple.  相似文献   
54.
目的:探究小檗碱对慢性萎缩性胃炎(CAG)的改善作用及其作用机制。方法:将SD大鼠随机分为对照组、模型组、小檗碱低剂量组、小檗碱中剂量组、小檗碱高剂量组和DUSP19组,每组9只。除对照组外均构建CAG模型,小檗碱低、中、高剂量分别灌胃给与25、50、100 mg/kg的小檗碱,DUSP19组灌胃给与100 mg/kg的小檗碱和尾静脉注射JAK激酶2/信号转导及转录激活因子3(JAK2/STAT3)通路激活剂DUSP19 100 μmol/L。苏木精-伊红(HE)染色法检测病理学变化;蛋白质印迹法检测JAK2/STAT3信号通路及凋亡相关蛋白表达;酶联免疫吸附试验(ELISA)检测血清相关因子表达水平;原位末端转移酶标记技术(TUNEL)检测胃黏膜细胞凋亡。结果:与模型组比较,小檗碱观察组磷酸化JAK2(p-JAK2)、磷酸化JAK3(p-JAK3)、胃动素(MTL)、肿瘤坏死因子-α(TNF-α)、白细胞介素6(IL-6)、白细胞介素-1β(IL-1β)、前列腺素E2(PGE2)、内皮素(ET)、B淋巴细胞瘤-2相关X蛋白(Bax)、裂解胱天蛋白酶3(Cl-caspase-3)、裂解胱天蛋白酶9(Cl-caspase-9)水平及细胞凋亡率显著降低(P<0.05),胃泌素(GAS)、分泌型免疫球蛋白A(sIgA)、谷胱甘肽(GSH)、B淋巴细胞瘤-2(Bcl-2)水平显著升高(P<0.05);JAK2/STAT3通路激活剂DUSP19可显著扭转小檗碱对上述指标的影响(P<0.05),且HE结果显示小檗碱可显著改善CAG大鼠胃组织病理病变。结论:小檗碱可通过JAK2/STAT3信号通路抑制细胞凋亡和炎症反应减轻大鼠慢性萎缩性胃炎。  相似文献   
55.
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   
56.
Objective: Our study aimed to evaluate short- and long-term outcomes of patients who required emergent conversion from transcatheter aortic valve implantation (TAVI) to open surgery. Besides, the reasons and procedural settings of emergent cardiac surgery (ECS) were also reported.Methods: We retrospectively reviewed the patients who underwent TAVI in our institution between 2012 and 2019 and collected the clinical data of cases who converted from TAVI to bail-out surgery. Telephone and outpatient follow-ups were performed.Results: Of 516 TAVI patients, 20 required ECS, and the bail-out surgery occurred less frequently with the increase in TAVI volume. The most common reason for conversion was left ventricular perforation (7/20, 35.0%). Thirty-day mortality was 35.0% in ECS patients. Kaplan–Meier survival curves showed that the cumulative survival rate was 65.0% at 1 year, 50.1% at 5 years in all ECS patients, and 77.1% at 5 years in patients who survived over 30 days after conversion.Conclusion: Although the bail-out operation was performed immediately after TAVI abortion, ECS still associated with high 30-day mortality. The long-term survival benefit was seen in patients surviving from bail-out surgery. An experienced TAVI team is of crucial importance in avoiding ECS-related life-threatening complications and providing effective salvage surgery.  相似文献   
57.
BackgroundHepatocellular carcinoma (HCC) is one of the most common causes of cancer worldwide. Although many studies have focused on oncogene characteristics, the genomic landscape of Chinese HCC patients has not been fully clarified.MethodsA total of 165 HCC patients, including 146 males and 19 females, were enrolled. The median age was 55 years (range, 27–78 years). Corresponding clinical and pathological information was collected for further analysis. A total of 168 tumor tissues from these patients were selected for next-generation sequencing (NGS)-based 450 panel gene sequencing. Genomic alterations including single nucleotide variations (SNV), short and long insertions and deletions (InDels), copy number variations, and gene rearrangements were analyzed. Tumor mutational burden (TMB) was measured by an algorithm developed in-house. The top quartile of HCC was classified as TMB high.ResultsA total of 1,004 genomic alterations were detected from 258 genes in 168 HCC tissues. TMB values were identified in 160 HCC specimens, with a median TMB of 5.4 Muts/Mb (range, 0–28.4 Muts/Mb) and a 75% TMB of 7.7 Muts/Mb. The most commonly mutated genes were TP53, TERT, CTNNB1, AXIN1, RB1, TSC2, CCND1, ARID1A, and FGF19. SNV was the most common mutation type and C:G>T:A and guanine transformation were the most common SNVs. Compared to wild-type patients, the proportion of Edmondson grade III–IV and microvascular invasion was significantly higher in TP53 mutated patients (P<0.05). The proportion of tumors invading the hepatic capsule was significantly higher in TERT mutated patients (P<0.05). The proportion of Edmondson grade I-II, alpha fetoprotein (AFP) <25 µmg/L, and those without a history of hepatitis B was significantly higher in CTNNB1 mutated patients (P<0.05). CTNNB1 mutations were associated with TMB high in HCC patients (P<0.05). Based on correlation analysis, the mutation of TP53 was independently correlated with microvascular invasion (P=0.002, OR =3.096) and Edmondson grade III–IV (P=0.008, OR =2.613). The mutation of TERT was independently correlated with tumor invasion of the liver capsule (P=0.001, OR =3.030), and the mutation of CTNNB1 was independently correlated with AFP (<25 µmg/L) (P=0.009, OR =3.414).ConclusionsThe most frequently mutated genes of HCC patients in China were TP53, TERT, and CTNNB1, which mainly lead to the occurrence and development of HCC by regulating the P53 pathway, Wnt pathway, and telomere repair pathway. There were more patients with microvascular invasion and Edmondson III–IV grade in TP53 mutated patients and more patients with hepatic capsule invasion in TERT mutated patients, while in CTNNB1 mutated patients, there were more patients with Edmondson I–II grade, AFP <25 µmg/L, and a non-hepatitis B background. Also, the TMB values were significantly higher in CTNNB1 mutated patients than in wild type patients.  相似文献   
58.
机器人技术在微创领域的作用越来越突出,而高质量护理工作的配合可以保障机器人手术的安全、有效进行,且有利于患者术后稳定情绪和更好的恢复.为提升护理工作者对MAKO机器人辅助单髁置换手术的全面认识,优化护理工作的模式和流程,提高手术效率并改善患者术后恢复效果,本文在现有的相关文献资料基础上,结合北京大学人民医院11例行机器人单髁置换手术的实际工作体会,用理论联系实际,对术中的护理配合工作进行系统地分析.本团队认为,在机器人辅助单髁置换手术中,护理工作应在传统经验积累的基础上,进一步提高护理配合熟练程度.随着科技的进步,MAKO机器人辅助单髁置换手术的医护模式也将进一步的智能化和数字化.  相似文献   
59.
目的 了解车祸致颅脑损伤患者家属的心理健康状况和社会支持状况,探讨其相关性。方法 采用自编一般资料调查表、症状自评量表(SCL - 90)和社会支持量表(SSRS),对225名到精神专科医院就诊的车祸致颅脑损伤患者家属进行问卷调查。结果 车祸致颅脑损伤患家属的SCL - 90总分为(178.45±82.56)分, SCL - 90总分、阳性项目数和9个因子分均显著高于肿瘤患者家属和全国常模(P<0.05)。社会支持总分为(38.52±8.23)分,社会支持水平与家属的心理健康状况呈显著的负相关(r = - 0.416, P<0.05)。多元线性回归分析显示,社会支持总分可以负向预测家属的心理健康状况(β = - 0.399,P<0.05)。结论 车祸致颅脑损伤患者家属的心理问题发生率较高,应从个人、家庭和社会层面为家属提供社会支持资源。  相似文献   
60.
目的 本研究旨在比较颅内大血管伴/不伴同侧颈内动脉闭塞的大动脉粥样硬化型脑卒中患者基线特征以及行血管内治疗后结局的差异。方法 对DIRECT-MT亚组进行回顾性分析,以比较前循环大动脉粥样硬化(large-artery atherosclerosis,LAA)型卒中串联闭塞和颅内闭塞接受血管内治疗(endovascular treatment,EVT)的患者的基线特征和预后,分析不同机制学特征(动脉粥样硬化或动脉-动脉栓塞)对临床结局的影响。结果 LAA型卒中患者共108例,其中串联闭塞63例,颅内闭塞45例。颅内闭塞组患者高血压史率高于串联闭塞组(77.8% vs. 52.4%, P=0.007)。颅内闭塞组闭塞部位最常见于大脑中动脉M1段(88.6%),而串联闭塞组颅内闭塞主要位于颈内动脉颅内段(49.2%)和大脑中动脉M1段(49.2%)(P<0.001)。两组患者在年龄、性别、术前抗栓、他汀类药物的使用,卒中、房颤、吸烟史,基线mRS、NIHSS评分,是否静脉溶栓,侧枝循环,以及救治流程时间差异均无统计学意义(P均>0.05)。90天mRS 0-2分的患者比例两组差异无统计学意义(53.3% vs. 41.9%, P=0.243)。颅内闭塞组术后成功再灌注率高于串联闭塞组(93.3% vs. 77.4%, P=0.026),但术后24-72小时血管再通的比例前组低于后组(57.1% vs. 77.2%, P=0.034)。最终梗死体积,颅内闭塞组小于串联闭塞组(20.1 vs. 34.5, P=0.025)。术后NIHSS评分,90天EQ-5D-5L评分和BI指数等其他次要结局,两组间差异无统计学意义(P均>0.05)。两组在90天内的死亡率,发生的无症状性和症状性颅内出血率,5-7天时在另外的血管区域新发脑梗死,以及新流域栓塞的患者百分比相似,差异无统计学意义(P均>0.05)。结论 动脉粥样硬化导致的串联闭塞相较于孤立颅内闭塞,末次造影成功再灌注率较低,梗死体积更大,但术后24-72小时再通率更高,且神经功能良好预后率以及不良事件发生率均与颅内闭塞相仿。  相似文献   
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