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71.
聚乙二醇修饰水蛭素的分离纯化与活性分析   总被引:4,自引:0,他引:4  
用活化的聚乙二醇(PEG)对水蛭素进行化学修饰,质谱分析表明,修饰产物是修饰度不同的分子质量相差5000u的水蛭素的混合物。用离子交换层析和凝胶过滤层析对反应产物进行分离纯化,离子交换层析难以达到完全分离;而采用凝胶过滤层析方法可较好地分离修饰度不同的各组份。生物学活性分析表明,不同的PEG修饰度对水蛭素的活性具有显著影响,连接1~2个PEG的水蛭素保持了原有活性,而连接3个PEG的水蛭素活性显著下降。  相似文献   
72.
PURPOSE: The authors evaluated the utility of hepatobiliary scintigraphy for tissue characterization of extrahepatic metastases from hepatocellular carcinoma (HCC) using Tc-99m N-pyrydoxyl-5-methyltriptophane (Tc-99m PMT). METHODS: We examined 13 patients with HCC (29 extrahepatic metastases and 3 benign bone lesions) and 5 patients with other cancers (15 extrahepatic metastases). Thirty minutes to 6 hours after intravenous administration of Tc-99m PMT, planar (all 47 lesions) and SPECT (42 lesions) images were obtained. Accumulation of Tc-99m PMT in the lesion was evaluated visually by comparing bone scintigraphy, computed tomography, magnetic resonance imaging, or all of these. RESULTS: Findings were positive in 12 of 13 patients with HCC and extrahepatic metastases (16 of 29 on planar imaging and 21 of 26 on SPECT). Findings in all three benign bone lesions and 15 metastatic lesions from non-HCC primary lesions were negative (0 of 18 on planar imaging, 0 of 16 on SPECT). There were no false-positive findings in these lesions. Lesion-by-lesion sensitivity, specificity, accuracy, and positive and negative predictive values were 55%, 100%, 72%, 100%, and 58% by planar imaging and 81%, 100%, 88%, 100%, and 76% by SPECT, respectively. CONCLUSIONS: Because of the high specificity and reasonable sensitivity, Tc-99m PMT appears to be useful for the differential diagnosis of extrahepatic metastases from HCC. SPECT improves the detectability of small or faint accumulation in metastases from HCC.  相似文献   
73.
目的 :了解辛伐他汀 (舒降之 )治疗老年人高脂血症的疗效。方法 :对 93例老年高脂血症患者采用舒降之治疗。结果 :治疗了 4周和 8周后 ,胆固醇 (TC)明显降低 2 2 %、2 7% (P <0 .0 1) ,低密度脂蛋白 (LDL C)明显降低 17%、2 4 % (P <0 .0 1) ,高密度脂蛋白 (HDL C)增加 15 %、16 % (P <0 .0 5 ) ,三酰甘油 (TG)降低 18%、2 1% (P <0 .0 5 ) ,仅有轻微不良反应。结论 :辛伐他汀可显著降低TC、LDL C ,可中等程度降低TG及升高HDL C。表明辛伐他汀是治疗老年人高脂血症的理想调脂药物  相似文献   
74.
OBJECTIVE: Transesophageal echocardiography was applied to visualizing endovascular procedures during transaortic stent grafting for aneurysm and dissection at the distal arch, and the use of transesophageal echocardiography was evaluated. METHODS: The 16 consecutive patients (13 with aneurysms and 3 with dissections) were examined. Transesophageal echocardiography was used for (1) determining graft size, (2) guiding placement of the catheter in the descending aorta at an appropriate position without intimal damage, (3) guiding graft tailoring with a balloon catheter, and (4) examining the results after the procedures. RESULTS: Visualization was disturbed in one patient who had undergone a previous operation. The graft size was appropriate, except in one patient as a result of underestimation. Transesophageal echocardiography was helpful for navigating the graft placement and tailoring without intimal damage. We tried to keep a distance from the diaphragm of 9 cm and an attachment portion of 4 cm. In one patient the graft was placed too distally (7 cm from the diaphragm) to cover the thick atheromatous plaque with the graft. The patient had paraplegia. Transesophageal echocardiographic assessment of endoleak and thromboexclusion was identical to that of postoperative computed tomography or angiography, with a sensitivity of 100% (1/1) and a specificity of 100% (13/13). Leakage at the proximal suture and graft kinking were found in 3 patients. Successful thromboexclusion by transesophageal echocardiographic assessment (13 patients) was predictive of subsequent regression of aneurysm and dissection in the midterm follow-up period: there was complete and partial regression in 5 and 8 patients, respectively. CONCLUSION: Transesophageal echocardiography enables echocardiography-assisted operations with secure step-by-step endoluminal procedures and immediate intraoperative assessment, which is predictive of the postoperative results.  相似文献   
75.
76.
管电压对胸部DR影像质量的影响   总被引:4,自引:0,他引:4  
目的 研究有效剂量相等条件下不同管电压对胸部DR图像质量的影响。方法 48例病人在90kV、125kV、150kV分别摄取后前位胸片,未经任何处理打印片子,五位资深放射专家采用五分法独立打分评估影像质量;采用Monte—Carlo转换因子估算有效剂量ED(mSv)。结果 绝大多数解剖结构在90千伏时得分最高(平均得分3.10),除了在心影轮廓、气管隆突和外围纹理方面以外,其余部位均有明显统计学差异。结论 有效剂量相等条件下采用较低千伏能获得更好胸部DR影像。  相似文献   
77.
Allele and genotype frequencies for eight DNA polymorphisms (HUMTH01, HUMVWA31A, D3S1358, D8S1179, D18S51, D19S253, YNZ22 and HLA-DQalpha) were determined in a population sample of Aymara Indians from Bolivia using PCR. No deviations of the observed allelic frequencies from Hardy-Weinberg equilibrium were found for all the systems studied. Significant differences in the allele frequencies were found between the Aymara and Quechua populations only for HUMVWA31A, which suggests a certain degree of genetic differentiation between the two populations.  相似文献   
78.
PurposeTo determine the location of coronary atherosclerosis distribution observed in patients with chronic kidney disease (CKD).MethodsA cross-sectional study was conducted using the database of cardiovascular medicine data from Saitama Sekishinkai Hospital to clarify the association between renal function and angiographic characteristics of coronary atherosclerosis. In total, 3268 patients who underwent percutaneous coronary intervention were included. Propensity score matching revised the total to 1772. The association of renal function with the location and/or distribution of coronary atherosclerosis lesions was then examined.ResultsOverall, coronary lesion was observed in the left anterior descending coronary artery (LAD) in 56% patients, whereas 28% and 22% were in the right coronary artery (RCA) and left circumflex coronary artery (LCX), respectively. LAD was most affected and observed in 57% patients with stage 1 CKD. RCA was second-most affected, at 26% CKD stage 1, but it increased to 31%, 38%, and 59% in CKD 3, 4, and 5, respectively. In CKD 5 patients, the RCA was the most affected artery (59%), with 41% LAD lesions. Logistic regression analysis after propensity score matching showed that the odds ratios for an RCA lesion was 3.658 in CKD 5 (p = .025) compared with CKD 1 after adjusting for traditional risk factors.ConclusionThe prevalence of RCA lesions, but not LAD or LCX lesions, increased with increasing CKD stage. The pathophysiology of coronary atherosclerosis may differ by lesion location. Deterioration of renal function may affect progression of atherosclerosis more in the RCA than in the LAD or LCX.  相似文献   
79.
Therapeutic nanoparticles are designed to enhance efficacy, real-time monitoring, targeting accuracy, biocompatibility, biodegradability, safety, and the synergy of diagnosis and treatment of diseases by leveraging the unique physicochemical and biological properties of well-developed bio-nanomaterials. Recently, bio-inspired metal nanoclusters (NCs) consisting of several to roughly dozens of atoms (<2 nm) have attracted increasing research interest, owing to their ultrafine size, tunable fluorescent capability, good biocompatibility, variable metallic composition, and extensive surface bio-functionalization. Hybrid core–shell nanostructures that effectively incorporate unique fluorescent inorganic moieties with various biomolecules, such as proteins (enzymes, antigens, and antibodies), DNA, and specific cells, create fluorescently visualized molecular nanoparticle. The resultant nanoparticles possess combinatorial properties and synergistic efficacy, such as simplicity, active bio-responsiveness, improved applicability, and low cost, for combination therapy, such as accurate targeting, bioimaging, and enhanced therapeutic and biocatalytic effects. In contrast to larger nanoparticles, bio-inspired metal NCs allow rapid renal clearance and better pharmacokinetics in biological systems. Notably, advances in nanoscience, interfacial chemistry, and biotechnologies have further spurred researchers to explore bio-inspired metal NCs for therapeutic purposes. The current review presents a comprehensive and timely overview of various metal NCs for various therapeutic applications, with a special emphasis on the design rationale behind the use of biomolecules/cells as the main scaffolds. In the different hybrid platform, we summarize the current challenges and emerging perspectives, which are expected to offer in-depth insight into the rational design of bio-inspired metal NCs for personalized treatment and clinical translation.Key words: Metal nanoclusters, Biomolecule, Nanoparticles, Hybrid system, Synergistic properties, Fluorescence, Bioprobe, Therapy  相似文献   
80.
蒙药胃舒安胶囊试验性胃溃疡的药效学研究   总被引:4,自引:0,他引:4  
目的研究经口给予胃舒安胶囊 (WSA)对试验性胃溃疡的预防及治疗作用。方法制备大、小鼠胃溃疡模型 ,多次灌胃给予受试动物WSA ,考查其对各种胃溃疡动物模型的保护作用。结果WSA对小鼠水应激、大鼠冰醋酸灼烧、大鼠乙醇诱导、大鼠幽门结扎所致的胃溃疡具有明显的保护作用。而且具有保护胃粘膜、中和胃酸、降低胃蛋白酶活性、抑制小鼠小肠推进速度、减少醋酸致痛小鼠的扭体次数的综合作用。结论WSA对大、小鼠试验性胃溃疡具有显著的疗效 ,能对抗由巴达干引起的胃溃疡。  相似文献   
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