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61.
目的:研究长柱重楼、滇重楼和南重楼的HPLC指纹图谱与其抗肝癌作用的谱效关系,为明确重楼抗肝癌作用的物质基础提供实验依据。方法:采用HPLC建立3种重楼提取物的指纹图谱,流动相乙腈(A)-水(B)梯度洗脱(0~10 min,20%A; 10~20 min,20%~25%A; 20~30 min,25%~30%A; 30~40 min,30%~35%A; 40~50 min,35%~40%A; 50~60 min,40%A; 60~75 min,40%~45%A; 75~80 min,45%~60%A),流速0. 9 m L·min~(-1),检测波长203 nm;利用噻唑蓝(MTT)比色法测定3种重楼提取物对肝癌HepG2细胞的增殖抑制作用,计算半数抑制浓度(IC_(50));运用聚类分析(HCA)和灰色关联度分析(GRA)研究3种重楼指纹图谱和抗肝癌作用的关系,找出对抗肝癌作用贡献较大的成分。结果:在3种重楼的HPLC指纹图谱中,确定其中11个色谱峰为共有峰。作用时间72 h时长柱重楼、滇重楼、南重楼的IC_(50)分别为148. 33,178. 87,208. 09 mg·L~(-1),其中长柱重楼的抗肝癌活性最强。灰色关联度结果显示,滇重楼共有峰中关联度较高的为1~10号峰,长柱重楼共有峰关联度较高的为1~7号峰,南重楼共有峰中关联度较高的为1~4,6~10,N1号峰,与IC_(50)关联度均0. 7。各重楼变量的聚类分析结果显示,可与IC_(50)聚为一类的色谱峰的关联度均 0. 7。结论:建立了3种重楼的HPLC指纹图谱,重复性良好。3种重楼中的1~4,6和7号色谱峰对抗肝癌药效贡献最大。  相似文献   
62.
目的以糖尿病心肌病大鼠为研究对象,探讨石斛合剂对糖尿病心肌病心肌细胞Ca^2+代谢的影响。方法 Wistar大鼠24只,取5只作为正常组,余19只采用高脂高糖饮食联合链脲佐菌素腹腔注射进行糖尿病心肌病造模。成模后,随机分为模型组、二甲双胍组、石斛合剂组。二甲双胍组、石斛合剂组分别予二甲双胍、石斛合剂灌胃,正常组、模型组予生理盐水灌胃。4周后,测空腹血糖,取左心室心肌组织进行组织病理学观察和心肌细胞内游离钙(MyoCa^2+)浓度测定,Western blot法检测肌浆网Ca^2+-ATP酶(SERCA2a)、L型钙通道α1C亚单位蛋白(CACNA1C)蛋白表达,RT-PCR法测定SERCA2a mRNA表达。结果石斛合剂组心肌纤维较模型组、二甲双胍组排列整齐,断裂较少。与正常组比较,模型组血糖、心肌细胞MyoCa^2+含量和CACNA1C蛋白表达明显升高(P<0.01,P<0.05),SERCA2a mRNA和蛋白表达明显降低(P<0.01)。与模型组比较,石斛合剂组血糖、心肌细胞MyoCa^2+含量和CACNA1C蛋白表达明显降低(P<0.01,P<0.05),SERCA2a mRNA和蛋白表达明显升高(P<0.01,P<0.05);二甲双胍组血糖明显降低(P<0.01)。与二甲双胍组比较,石斛合剂组心肌细胞MyoCa^2+含量明显降低(P<0.01,P<0.05),血糖、SERCA2a mRNA和蛋白表达明显升高(P<0.05)。结论石斛合剂通过提高SERCA2a mRNA和蛋白表达,加快摄取Ca^2+的速率,降低细胞质Ca^2+负荷,缓解钙超载,最终达到维持糖尿病心肌病钙稳态的作用,有效维持心肌细胞的正常收缩舒张功能;其降糖作用不是预防糖尿病心肌病的主要机理,而在于抑制CACNA1C蛋白表达,抑制钙诱导钙释放过程。  相似文献   
63.
64.
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence.  相似文献   
65.
BackgroundGrowth hormone (GH)-producing pituitary tumors account for 10 to 15% of pituitary tumors. The hypersecretion of GH may induce changes in the airway anatomy through the activation of Insulin-like Growth factor 1(IGF-1) pathway. We sought investigate the role IGF-1 as a potential predictive factor of difficult laryngoscopy in patients with GH-producing pituitary adenoma.MethodsThis study was a single center retrospective study. We included 33 patients undergoing transsphenoidal resection of GH-producing pituitary. We recorded demographic data, el-Ganzouri risk index (EGRI) and modified Look-Evaluate-Mallampati-Obstruction-Neck mobility (mLEMON) score, and pituitary hormone plasma levels. We performed ordinal logistic regression to analyze the relationship between IGF-1 and EGRI, mLEMON, and Cormack-Lehane Grade score and a multiple logistic regression to test the capability of EGRI, mLEMON and IGF-1 levels to predict Cormack-Lehane score. Receiver operating curve (ROC), area under the curve (AUC), and cut-off value of IGF-1 were calculated.ResultsOnly 14 (42.8%) and 12 (36.36%) patients showed predictive factors of difficult intubation according to EGRI and mLEMON score, respectively. IGF-1 significantly correlated with Cormack-Lehane (p = 0.005879) but not with mLEMON and EGRI (p = 0.3080 and 0.4146, respectively). In multiple regression model IGF-1 correlated only with Cormack-Lehane grade (p = 0.0089). Area under ROC was 0.8571 and cut-off value of IGF-1 was 186.15 ng/ml.ConclusionHigher IGF-1 levels correlate with the probability of having a higher Cormack-Lehane score; classical bedside scores, such as mLEMON and EGRI, were not able to predict difficult laryngoscopy in our population.  相似文献   
66.

Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
67.
68.
ABSTRACT

Introduction

Type 1 diabetes mellitus (T1DM) is a chronic, autoimmune disease that is characterized by total absence of insulin production. Hypertension is a common comorbidity in T1DM with complex pathophysiology, while it is also a well-recognized risk factor for the development of cardiovascular disease (CVD), as well as other microvascular diabetic complications.  相似文献   
69.
目的探讨1 470 nm激光剜除治疗高危前列腺增生的手术技巧及临床效果。 方法回顾分析2018年6月至2018年9月中山大学附属第三医院泌尿外科采用1 470 nm激光治疗共89例高危前列腺增生患者的临床资料,年龄平均(68±3)岁,前列腺体积(57.4±2.6)ml。所有患者均采用"寻找层面,先易后难,剜切结合"的层面递进法思路行激光腔内前列腺剜除术,比较患者术中及术后情况。 结果89例均顺利完成手术,与术前相比,术后3个月患者最大尿流率明显增加,[(6.9±2.1) ml/s vs(19.8±3.6) ml/s]。国际前列腺症状评分显著好转,[(24.6±1.7) vs(8.0±1.2)]。术中无输血、无电切综合征、无直肠和膀胱穿孔病例,无输尿管损伤、大出血、心脑血管意外等严重并发症发生。 结论层面递进法激光剜除技术构想对于高危前列腺增生外科包膜层面的寻找、减少术后并发症有独到优势,且易于掌握,或可为业界同行提供一个新的思路。  相似文献   
70.
Cis-diamminedichloridoplatinum(II)(CDDP)-based combination chemotherapy is frequently used in gastrointestinal cancer. The synergistic mechanism of all-trans retinoic acid (ATRA), cisplatin (CDDP) and 5-fluorouracil (5-FU) in combination remains unclear. Despite their potent antitumor properties, resistance to CDDP and 5-FU develops frequently in tumors. To clarify this mechanism, we determined the sensitivity to each drug and their combination in two gastrointestinal cancer stem cells (CSCs) subpopulation.Here, we report the identification and separation of CD44+ cells from human gastric carcinoma (AGS) and human esophageal squamous cell carcinoma (KYSE-30) cancer cell lines by magnetic activated cell sorting (MACS). We allowed the CD44± cells to grow 6 days at a subtoxic concentration of ATRA and then treated with different concentration of CDDP and 5-FU for 24 h. The cytotoxicity was examined by cell proliferation MTT assay. Additionally, AO/EB staining was used for detection of apoptotic cells. In order to determine whether the growth inhibition was also associated with changes in cell cycle distribution, cell cycle analysis was performed using flow cytometry.Low concentration of ATRA (1 μM, 6days) followed by 5-FU and CDDP was found to be more effective than either drugs alone, thus resulting in synergistic cytotoxicity in Kyse-30 and AGSCD44± cells. Furthermore, there was an indication that the combination of ATRA with 5FU and CDDP caused an increase in cell cycle arrest in G2/M and G0/G1.We conclude that low concentration of ATRA enhances the cytotoxicity of CDDP and 5FU by facilitating apoptosis and cell cycle arrest in gastrointestinal CSCs and provide a rational basis for the design of novel, well-tolerated CDDP- and 5FU-based chemotherapy in human gastrointestinal carcinoma.  相似文献   
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