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1.
Clinical and Experimental Medicine - Colon cancer is one of most common cancers. The progression of various cancers is driven by miRNA-570. The role of miRNA-570 in the progression of colon cancer...  相似文献   
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Peptide-targeted alpha-therapy with 7.4 MBq of (212)Pb-[1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-ReO-[Cys(3,4,10),d-Phe(7),Arg(11)]alpha-MSH(3-13) ((212)Pb-DOTA-Re(Arg(11))CCMSH) cured 45% of B16/F1 murine melanoma-bearing C57 mice in a 120-d study, highlighting its melanoma treatment potential. However, there is a need to develop an imaging surrogate for patient-specific dosimetry and to monitor the tumor response to (212)Pb-DOTA-Re(Arg(11))CCMSH therapy. The purpose of this study was to evaluate the potential of (203)Pb-DOTA-Re(Arg(11))CCMSH as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH. METHODS: DOTA-Re(Arg(11))CCMSH was labeled with (203)Pb in 0.5 M NH(4)OAc buffer at pH 5.4. The internalization and efflux of (203)Pb-DOTA-Re(Arg(11))CCMSH were determined in B16/F1 melanoma cells. The pharmacokinetics of (203)Pb-DOTA-Re(Arg(11))CCMSH was examined in B16/F1 melanoma-bearing C57 mice. A micro-SPECT/CT study was performed with (203)Pb-DOTA-Re(Arg(11))CCMSH in a B16/F1 melanoma-bearing C57 mouse at 2 h after injection. RESULTS: (203)Pb-DOTA-Re(Arg(11))CCMSH was easily prepared in NH(4)OAc buffer and completely separated from the excess nonradiolabeled peptide by reversed-phase high-performance liquid chromatography (RP-HPLC). (203)Pb-DOTA-Re(Arg(11))CCMSH displayed fast internalization and extended retention in B16/F1 cells. Approximately 73% of (203)Pb-DOTA-Re(Arg(11))CCMSH activity internalized after a 20-min incubation at 25 degrees C. After incubation of the cells in culture medium for 20 min, 78% of internalized activity remained in the cells. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a biodistribution pattern similar to that of (212)Pb-DOTA-Re(Arg(11))CCMSH in B16/F1 melanoma-bearing mice. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor uptake of 12.00+/-3.20 percentage injected dose per gram (%ID/g) at 1 h after injection. The tumor uptake gradually decreased to 3.43+/-1.12 %ID/g at 48 h after injection. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor-to-kidney uptake ratio of 1.53 at 2 h after injection. The absorbed doses to the tumor and kidneys were 4.32 and 4.35 Gy, respectively, per 37 MBq. Whole-body clearance of (203)Pb-DOTA-Re(Arg(11))CCMSH was fast, with approximately 89% of the injected activity cleared through the urinary system by 2 h after injection. (203)Pb showed 1.6-mm SPECT resolution, which was comparable to (99m)Tc. Melanoma lesions were visualized through SPECT/CT images of (203)Pb-DOTA-Re(Arg(11))CCMSH at 2 h after injection. CONCLUSION: (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited favorable pharmacokinetic and tumor imaging properties, highlighting its potential as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH melanoma treatment.  相似文献   
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血管腔内支架成形术治疗下肢动脉硬化闭塞症45例   总被引:10,自引:0,他引:10  
目的探讨血管腔内支架成形术治疗下肢动脉硬化闭塞症的疗效。方法采用经皮穿刺股动脉或切开动脉直视下穿刺,造影明确病变动脉部位及病变长度后,利用导丝或超声消融导管开通闭塞段,球囊导管行扩张成形后置入血管内支架。结果45例(53条患肢)血管腔内支架均释放成功,踝肱指数由0.36±0.14增至术后7 d 0.77±0.21(t=2.397,P=0.021),45例随访6~54个月,平均23个月,一期肢体通畅率90.6%(48/53)。结论血管腔内支架成形术操作简便、微创、安全是治疗下肢动脉硬化闭塞症的有效方法。  相似文献   
5.
对猪胰脏中提取胰酶的多种条件进行了详细研究。在本文条件下,胰蛋白酶、胰脂肪酶、胰淀粉酶三酶活力分别达4200u/g,3600u/g,5000u/g以上,收率10-13%。  相似文献   
6.
目的:探讨新生大鼠内毒素休克脑损伤时脑一氧化氮合成酶(NO6)三种亚型基因表达的变化及地塞米松(DEX)对其的调控作用。方法:在新生大鼠内毒素休克动物模型基础上,采用逆转录PCR及PCR技术,对脑组织中三型NOS mRNA及caspase—3 mRNA的表达进行半定量分析。结果:正常新生大鼠脑iNOS及eNOS mRNA无明显表达,nNOS mRNA、caspase—3 mRNA有一定程度表达。内毒素脂多糖(LPS)腹腔注射后2h,三种亚型NOS mRNA开始表达,于LPS6h达高峰,并持续至24h。caspase—3 mRNA于LPS腹腔注射后2h后表达逐渐增加,24h达高峰。DEX可抑制nNOS、iNOS及caspase—3 mRNA的表达,且以用药后2h最为明显,并持续至用药后24h。结论:内毒素休克脑损伤时,各型NOS均有表达,NO的产生是内毒素休克脑损伤时重要的病理生理机制之一。DEX通过抑制NOS、caspase—3 mRNA的表达部分实现其神经保护作用.  相似文献   
7.
Recombinant human serum albumin including 2-[8-[N-(2-methylimidazolyl)]octanoyloxymethyl]-5,10,15,20-tetrakis(alpha,alpha,alpha,alpha-o-pivaloylamino)phenylporphinatoiron(II) (albumin-heme; rHSA-FeP) is a synthetic hemoprotein that has sufficient capability to reversibly bind and release O(2) under physiological conditions (pH 7.3, 37 degrees C) similar to hemoglobin and myoglobin. In order to use this albumin-based O(2) carrier as a new class of red blood cell substitutes, its compatibility with blood cell components carefully was investigated in vitro. After the addition of the rHSA-FeP solution into whole blood at 10, 20, and 44 vol %, the FeP concentration in the plasma phase remained constant for 6 h at 37 degrees C in each group, and no significant time dependence was observed in the numbers of red blood cells, white blood cells, or platelets. The microscopic observations clearly showed that the shapes of the red blood cells had not been deformed during the measurement period. With respect to the blood coagulation parameters (prothrombin time and activated partial thromboplastin time), the coexistence of rHSA-FeP had only a negligibly small influence. Also the blood compatibility under dynamic flow conditions was evaluated using a microchannel array flow analyzer. All these results suggest that the albumin-heme has no effect on the morphology of blood cell components in vitro.  相似文献   
8.
Right heart thrombus (RHTh) with concurrent acute pulmonary embolism (PE) is rare and can seriously destabilize hemodynamics, leading to an emergency situation with high mortality. Diagnosis and treatment of RHTh with acute PE are not yet standardized. There are few reports of acute PE concurrent with RHTh and even less is known about patients with a right heart mural thrombus. For physicians, the diagnostic choice and treatment of these patients are particularly difficult due to the lack of knowledge. Here, we report a rare case of partial mural RHTh (type C RHTh) with acute PE. The mural mass in the right heart was initially diagnosed as atrial myxoma according to transthoracic echocardiography (TTE), and both pulmonary embolus and the mural mass were completely absorbed after administering Rivaroxiban. This case suggests that TTE alone is insufficient to identify and diagnoses a right heart mural mass such as this. However, novel oral anticoagulants may be effective at alleviating PE with type C RHTh.  相似文献   
9.
大学新生MMPI结果与分析   总被引:4,自引:2,他引:4  
目的:探讨大学新生的个性特征和心理问题特征,为高校有效开展大学生心理健康教育提供参考依据;方式:采用MMPI量表,以问卷的形式,连续对4届2674名大学生进行了调查;结果:原始分值总体呈下降的趋势,效度量表中F为高T分点,临床量表中Sc为高T分点,男生的TSc在70-80之间,女生的TSc在60-70之间。男生临床量表高分两点编码分别为85/58、89/98、82/28、82/28,女性临床量表高分两点编码分别为85/58、86/68、89/98、85/58。大学新生存在着焦虑紧张、情绪不稳、敏感多疑、胆小退缩、与现实脱节等倾向;结论:大学生的心理健康教育应始于新生入学教育,并广泛开发新生心理测查工作。  相似文献   
10.
支气管扩张症中神经内分泌免疫网络及肥大细胞的变化   总被引:1,自引:0,他引:1  
目的:探讨支气管扩张症中神经内分泌免疫网络的异常和肥大细胞(MC)在该病发病中的作用及关系。方法:应用组织化学、免疫组化、组织化学与免疫组化结合的方法和形态计量学方法进行观测。结果:支气管扩张症中,支气管上皮蛙皮素(Bombesin)阳性细胞、固有膜S-100蛋白和神经特异性烯醇化酶(NSE)阳性神经纤维、IgE阳性细胞、MC和IgE阳性MC均显著增多,且在支气管相关淋巴组织(BALT)增生的区域上述肺内分泌细胞、神经纤维和IgE阳性细胞增多尤为显著,S-100蛋白和NSE阳性神经纤维分布于弥散淋巴组织和BALT中,MC与S-100蛋白阳性神经纤维紧密接触.MC表面有IgE阳性环状带,MC和IgE阳性细胞出现在支气管上皮间和肺泡壁。结论:支气管扩张症的发病与局部神经内分泌免疫网络异常有关;MC可能作为感受器、分泌细胞或靶细胞参与神经内分泌免疫网络,在支气管扩张症的发病中起重要作用。  相似文献   
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