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91.
水通道蛋白-9(AQP9)是水通道蛋白家族中特殊的一员,对水和多种中性溶质均具有转运活性.AQP9在脑内主要分布于神经胶质细胞、内皮细胞和儿茶酚胺能神经元.目前AQP9在脑内的功能还不完全清楚,初步认为除维持脑内水代谢平衡外,还可能在能量代谢方面发挥重要作用.AQP9与脑部涉及水或能量代谢的疾病如脑血管病、帕金森病和脑肿瘤等密切相关.  相似文献   
92.
ObjectiveThe postoperative role of adjuvant radiotherapy in non-metastatic head and neck adenoid cystic carcinoma (ACC) remains controversial. We analyzed adjuvant radiotherapy’s effect on surgical patient survival.MethodsPatients diagnosed with ACC from 2004 to 2015 in the Surveillance, Epidemiology, and End Results database were analyzed. The overall survival (OS) and disease-specific survival (DSS) of patients after adjuvant radiotherapy were assessed using the Kaplan–Meier and multivariate Cox methods. Propensity score matching (PSM) was performed to adjust confounders between patients with or without adjuvant radiotherapy; a forest plot was generated by subgroup analysis.ResultsThe study included 742 patients. In the PSM cohort, adjuvant radiotherapy did not improve OS or DSS. Radiotherapy was not a protective factor for OS or DSS in the univariate and multivariate Cox proportional hazard models. In the subgroup analysis, postoperative radiotherapy improved the OS of female and N1-stage patients and those with oropharyngeal tumors or over 79 years and the DSS of N1-stage patients.ConclusionsPostoperative radiotherapy showed different benefits in ACC patients, and postoperative radiotherapy recommendations should be individualized. Female and N1-stage ACC patients and those with oropharyngeal tumors or patients over 79 years without distant metastases postoperatively could benefit from adjuvant radiotherapy.  相似文献   
93.
The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method. A simple and highly sensitive electrochemical sensing platform for electrochemical rGO and modified CeO2 nanoribbons directly on FTO electrodes was developed. Simultaneous determination of Pb2+ and Cd2+ used the differential pulse anodic stripping voltammetry (DPASV) method. The method was simple to operate, and CeO2 nanobelts could be obtained simultaneously by electrodeposition and reduction of GO without further processing. This is an environmentally friendly electrochemical method to obtain modified electrodes under mild conditions. The experimental results showed that the linear calibration curves of Pb2+ and Cd2+ are 1–300 and 0.2–500 μg L−1, respectively. At the same time, no interference from other coexisting metal ions was found during the detection process, which proved that the modified electrode had good stability and repeatability.

The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method.  相似文献   
94.
BackgroundOur previous study showed that two different regimens of moderate hypofractionated radiotherapy (HFRT) delivered with helical tomotherapy (HT) are well tolerated in older prostate cancer patients. We provide a longterm efficacy and toxicity after > 7 years of follow-up.Patients and methodsThe study recruited 33 patients from February 2009 to July 2011 (76 Gy/34F; Group-1); and 34 from July 2011 to February 2014 (71.6 Gy/28F; 50.4 Gy/25F for the risk of pelvic lymph nodes involvement (LNI) >15%; Group-2). The primary outcomes were biochemical failure (BF), biochemical failure and clinical disease failure (BCDF), progression-free survival (PFS), overall survival (OS), late genitourinary (GU) and gastrointestinal (GI) toxicity.ResultsThe average ages of two groups were 80 and 77 years and the proportions of patients with LNI > 15% were 69.7% and 73.5%, respectively. At the final follow-up in February 2020, 27.3% and 20.6% cases experienced BF, with a median time until BF of 3.3 years. A total of 38.8% patients reached primary endpoints, in which 18 deaths were reported BCDF events (45.5% vs. 32.4%, p = 0.271). There was no significant difference in 7-year PFS (68.6% vs. 74.8%, p = 0.591), BCDF (45.5% vs. 32.4%, p = 0.271) and OS (71.9% vs. 87.5%, p = 0.376) for full set analysis and for subgroup analysis (all p > 0.05). The incidence of grade ≥ 2 late GU (6.2% vs. 6.3%, p = 0.127) and GI toxicities (9.4% vs. 15.6%, p = 0.554) was comparable.ConclusionsIn older patients with localized prostate cancer, two moderate hypofractionated regimens were all well tolerated with similar, mild late toxicities and satisfactory survival, without necessity of prophylactic pelvic node irradiation.Key words: helical tomotherapy, radiation dose hypofractionation, progression-free survival, follow-up studies, prostatic neoplasms, adenocarcinoma  相似文献   
95.
We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.  相似文献   
96.
44 cats were used in this experiment. The spinal cords of 40 animals were injuredat about L_1 level by using Allen's method (400g/cm) and randomly divided into 2 groups: A)electro-acupuncture treatment group (n=20) and B) control group(n=20). 2 weeks after spinalcord injury, 80% of animals in the treatment group were survival and 45% of animals in the con-trol group were survival. There was significant difference between these two groups (p<0. 05).The motor evoked potential was recorded two weeks after spinal cord injury. The latency of theshort latency peak was 15. 61±4. 98 mS and the amplitude was 10. 61 0. 59 mV in the treatmentgroup; and 21. 7±5. 02 mS and 0. 56±0. 32 mV in the control group. Both latency and amplitudewere significant different between the two groups (P<0. 05, P<0. 05). The Anti-NF-H (neuro-filament) was determined at 2 and 4 weeks respectively after spinal cord injury. The more NF-Hpositive labeling fibers were found in the treatment group than in the control group (P<0. 01 ).The  相似文献   
97.
百蕊含片的质量标准研究   总被引:6,自引:1,他引:6  
采用TLC法对百蕊含片中山柰素进行鉴别;用HPLC法测定山柰素的含量;含量限度为山柰素量不少于0.30mg/片。  相似文献   
98.
中药具有多成分、多靶点的特性,药效物质基础及药物代谢途径不明确严重制约中药的发展。中药小分子经过体内代谢后转化成代谢物发挥药效或者清除。近年来随着MS技术的飞速发展,通过LC-MS技术进行精准定性定量分析,以阐明中药代谢物与机体生理及病理相关变化的关系,从而明确中药的药效物质基础及体内代谢路径。本文从中药代谢研究思路、研究方法、影响因素以及应用等方面,就近年来中药代谢分析领域的研究进展进行综述。  相似文献   
99.
目的探讨采用瘤块种植制备兔肝VX2肿瘤模型的可行性并研究其生物学特性。方法采用VX2肿瘤组织块制备兔肝肿瘤模型,观察谷丙转氨酶(ALT)、体温、体质量、体液免疫球蛋白、肿瘤的增长、脏器转移及组织病理学改变等。结果兔肝VX2肿瘤原位移植模型的移植成功率为100%,6周肝内转移率为100%,6周肺转移率为80%。随着瘤体体积的增长,体温及ALT逐渐升高,体质量逐渐减轻,免疫球蛋白则呈下降趋势。超声检查显示肝脏有结节样增强回声。肿瘤呈灰白色,质硬,光镜下可见癌细胞核大,深染伴核异型。结论采用瘤块种植制备兔肝VX2肿瘤模型,具有容易制备、生长周期短、成功率高及模型稳定等特点,是一种较理想的肝肿瘤实验动物模型。  相似文献   
100.
金熊胆安胶囊中姜黄素的含量测定   总被引:1,自引:0,他引:1  
目的:制订金熊胆安胶囊含量测定指标。方法:样品经四氢呋喃冷浸2次提取后,采用反相高效液相色谱法测定姜黄素的含量。结果:采用该测定方法重现性良好。结论:采用该法对样品中郁金所含姜黄素进行含量测定,可有效地控制原料和制剂的质量。  相似文献   
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