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71.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献
72.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献
73.
目的:观察解毒通络方对脑缺血大鼠恢复期海马与皮质中单胺类递质和乙酰胆碱含量的影响。方法:实验于2005-05/2006-02在北京中医药大学病理实验室与中国中医科学院西苑中医院药理实验室完成。选择健康SD大鼠150只,采用双侧颈总动脉夹闭结合低血压状态制作脑缺血模型,将造模成功的150只大鼠随机数字表法分为5组,正常组、模型组及解毒通络方低剂量组、中剂量组、高剂量组,各30只。每组又分为造模后4,8周2个时相点,每个时相点15只。各剂量治疗组每天按不同剂量灌服解毒通络口服液(由栀子、丹参、黄芪、天麻等组成),低、中、高剂量分别相当于生药1.85,3.7,7.4g/kg,配置成给药体积为5mL/kg的溶液;模型组、正常组同时灌胃相应体积的洁净水。以改进的柱前、柱后双酶柱结合高效液相电化学方法检测大鼠海马与皮质的乙酰胆碱含量;以高效液相电化学方法检测大鼠海马与皮质的单胺类神经递质及其代谢产物的含量。结果:纳入动物150只,均进入结果分析。①脑缺血后4周模型组大鼠海马去甲肾上腺素水平与正常组比较显著升高[分别为(797.29±60.04),(528.90±149.13)μg/L,P<0.01]、乙酰胆碱水平显著降低[分别为(19.72±10.09),(39.73±22.31)μg/L,P<0.01],皮质去甲肾上腺素、高香草酸水平与正常组比较显著降低[分别为(52.81±21.71),(258.65±125.82)μg/L,P<0.01;(5.22±3.19),(9.02±2.27)μg/L,P<0.05],海马与皮质多巴胺、5-羟色胺及其他代谢物及皮质乙酰胆碱水平均无明显变化。②脑缺血后8周模型组大鼠海马去甲肾上腺素、多巴胺水平与正常组比较显著升高[分别为(346.88±125.98),(110.76±18.56)μg/L,P<0.05;(7.16±3.52),(3.78±0.44)μg/L,P<0.01],5-羟色胺、乙酰胆碱水平显著降低[分别为(79.38±26.47),(127.64±23.03)μg/L,P<0.01;(14.75±5.21),(22.59±6.58)μg/L,P<0.05],皮质去甲肾上腺素水平也显著降低[分别为(57.67±18.30),(133.43±39.15)μg/L,P<0.01],皮质单胺类递质代谢产物及乙酰胆碱水平则无明显变化。解毒通络方可使上述各项指标的绝大部分恢复到接近正常大鼠水平。结论:解毒通络方能够有效促进脑缺血大鼠海马与皮质中单胺类递质和乙酰胆碱代谢紊乱状态的恢复。 相似文献
74.
目的 对北京市实施2剂次水痘疫苗免疫策略后发生的一起小学水痘暴发疫情开展调查,分析导致疫情发生的预防接种相关因素.方法 采用回顾性队列研究方法,利用传染病网络直报系统和疫情期间主动监测系统发现水痘病例,回顾调查全校学生水痘患病史和水痘疫苗免疫史,比较不同免疫史学生的罹患率.结果 总罹患率为2.3%(30/1282),其中0剂次组罹患率5.9%(1/17),1剂次组罹患率4.2%(22/527),2剂次组罹患率0.9%(7/738).总体疫苗接种率为98.7%(1265/1282),其中1剂次接种率41.1%(527/1282),2剂次接种率57.6%(738/1282).1剂次组发病风险是2剂次组的4.5倍,差异有统计学意义(x2=14.285,P<0.01),2剂次比1剂次增加77.3%的保护率;2剂次组中接种时间间隔<3年的罹患率为0,间隔4至5年的罹患率为0.9%,间隔≥6年的罹患率为2.7%(x2趋势=6.762,P=0.013).结论 2剂次水痘疫苗保护率较1剂次显著提高.2剂次疫苗长期保护效果仍需进一步定量评价. 相似文献
75.
牙本质发育不全(DI)是一种遗传性疾病,患者牙本质发生病变,尤其多发于恒牙。患牙临床表现为棕黄色、釉质缺失、过度磨耗等,修复治疗这类牙具有极高的挑战性。本文报道1例用固定义齿联合活动义齿修复牙本质发育不全的患者。 相似文献
76.
Gao-Xiong Rao Sen Zhang Hui-Min Wang Zhi-Min Li Suo Gao Gui-Li Xu 《Journal of ethnopharmacology》2009
Aim of the study
The rattan stem of Fibraurea recisa Pierre. is known as an ethno-remedy commonly used for the treatment of various skin diseases by the minority Yao, Zhuang and Miao in Yunnan Province of China. The present study was designated to evaluate its antifungal activity, and to root out the antifungal substances from this ethical herb.Materials and methods
The in vitro antifungal assay was performed by agar diffusion test for extracts and fractions. Then, the active fractions were submitted to column chromatography on silica gel and LH-20 to isolate their compounds. And the antifungal activity of pure compounds has been examined by checkerboard microdilution test. Nine Candida strains and one Cryptococcus strain were used for the bioassay.Results
The MeOH extract exhibited significant antifungal activity, and the alkaloidal fractions were deduced as main active component. Subsequent studies led to the identification of a new alkaloid fibrecisine (1) and 21 known alkaloids including berberines, tetrahydroberberines and aporphine derivatives. The bioassay result indicated that the berberines showed more potent activity than aporphine derivatives against the test Candida strains, while tetrahydroberberines showed very weak activity against Cryptococcus neoformans.Conclusion
The new alkaloid fibrecisine (1) was identified as 1,2-methylenedioxy-8-hydroxy-6a(R)-aporphine by detailed spectral analysis. The rattan stem of Fibraurea recisa Pierre. is an effective antifungal herb, and its major active component is alkaloidal compounds. Bioassay tests revealed that the water-soluble berberines are the most important antifungal substances. The study provides preliminary scientific validation for the traditional medicinal use of this ethno-remedy. 相似文献77.
Wenbo He Jiaxiang Bai Xu Chen Di Suo Shenghao Wang Qianping Guo Weiling Yin Dechun Geng Miao Wang Guoqing Pan Xin Zhao Bin Li 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(8)
Dynamic biomaterials excel at recapitulating the reversible interlocking and remoldable structure of the extracellular matrix (ECM), particularly in manipulating cell behaviors and adapting to tissue morphogenesis. While strategies based on dynamic chemistries have been extensively studied for ECM-mimicking dynamic biomaterials, biocompatible molecular means with biogenicity are still rare. Here, we report a nature-derived strategy for fabrication of dynamic biointerface as well as a three-dimensional (3D) hydrogel structure based on reversible receptor–ligand interaction between the glycopeptide antibiotic vancomycin and dipeptide d-Ala-d-Ala. We demonstrate the reversible regulation of multiple cell types with the dynamic biointerface and successfully implement the dynamic hydrogel as a functional antibacterial 3D scaffold to treat tissue repair. In view of the biogenicity and high applicability, this nature-derived reversible molecular strategy will bring opportunities for malleable biomaterial design with great potential in biomedicine.More than 2,500 y ago, the Chinese built their nail- and glue-less architectures (e.g., from Beijing''s Forbidden City to Sichuan Province''s Bao''en Temple) with a “dougong” structure, which is part of the network of wooden supports essential to the timber frame structure of the building. A typical dougong consists of a flat block of wood (dou), the top of which is fixed with an interlocking set of curved bows (gong), without the aid of nails or glue, to provide mechanical support to hold the three-dimensional (3D) network structure. Intriguingly, the microstructure of extracellular matrix (ECM) also demonstrates such reversible interlocking structure, which supports the integrity of tissues and organs. In natural ECM, the dougong structure occurs at the cell–ECM interfaces accompanied by a constant remodeling of the ECM network, giving rise to specific cell signaling, intracellular cascades, and subsequently, all relevant cell behaviors (1–3). Biomaterial designs based on the reversible interactions mimicking the cell–ECM interfaces are believed to boast distinct advantages, including the capability to modulate cell–biomaterial interactions, adapt to the development of cellular processes (1, 4–6), and facilitate the morphogenesis of tissues and organs (7, 8). Although the dynamic design of biomaterials is relatively complicated and challenging, this field attracts significant attention in building dynamic ECM mimics for regenerative medicine (1, 9–11).To faithfully reproduce the dynamics of ECM in artificial matrices, various strategies, including congenitally reversible noncovalent interactions (e.g., hydrogen bonds, coordinate bonds, hydrophobic forces, π–π interactions, van der Waals forces, and electrostatic effects) and dynamic covalent bonds (e.g., reversible boronic esters and benzoic–imine bonds and photosensitive nitrophenyl and azobenzene groups), have been exploited. Currently, biomaterial interfaces with dynamically functionalized bioligands are mainly designed through reversible covalent phenylboronic esters or benzoic–imine bonds (12–16), deformable azobenzene bonds (17), DNA and peptide molecular assemblies (18, 19), cyclodextrins/cucurbiturils-based macrocycle host–guest supermolecules (20–22), metal–ligand coordination (23, 24), and other multiple noncovalent interactions (25–29). They can elicit controllable and reversible cell behaviors (e.g., adhesion, migration, differentiation, and apoptosis) on the biomaterial interfaces (1, 4, 8). Unfortunately, these dynamic ECM-mimicking strategies carry critical problems (13). First, most dynamic strategies are based on nonbiogenic chemical molecules, which are usually nonbiocompatible and probably harmful. Second, the dynamics of these strategies commonly rely on the nonbiological stimuli (e.g., ultraviolet [UV] light or toxic chemicals), which are potentially invasive to cells. Third, current studies on mimicking dynamic ECM are usually limited to either reversible bioligand presentation or remoldable network fabrication; few works focus on both. In this context, the exploration of biocompatible molecular means for recapitulation of both dynamic bioactivity and dynamic structure in ECM is highly anticipated.Here, we present a nature-derived reversible strategy inspired by the receptor–ligand molecular recognition for design of dynamic ECM-mimicking biomaterial. The receptor–ligand molecular recognition relies on multi-noncovalent interaction between two or more molecules with exquisite complementarity in their chemical groups and geometries (30). With this in mind, we focus our attention on a typical simple yet elegant receptor–ligand system (i.e., the glycopeptide antibiotic vancomycin [Van] and the dipeptide d-Ala-d-Ala [AA]). Produced by a bacterial species named Amycolatopsis orientalis, Van exhibits strong bactericidal effect by inhibiting cell wall biosynthesis via the specific binding (Kd = 1.6 μM) (31) toward the terminal AA dipeptide of the bacterial cell wall precursors (Fig. 1A). As a proof of concept, we employ the reversible Van–AA interaction for building both a reversible dynamic biointerface and a 3D hydrogel network (Fig. 1 B and C). Due to the specific but reversible AA–Van molecular recognition, the dynamic biointerface demonstrates excellent reversibility in binding to cell-adhesive tripeptide arginylglycylaspartic acid (RGD) and modulating adhesion of multiple cells, demonstrating our strategy’s general applicability. In addition, the 3D hydrogel network based on the reversible AA–Van molecular recognition demonstrates self-recovery and injectability. The inherently antibacterial activity of the Van–AA hydrogel well equips the 3D hydrogel network for treating infected open skin wounds; the hydrogel could adapt to the shape of wound sites, resist self-fragmentation, and inhibit proliferation of pathogenic bacteria while continuously supporting wound healing. We believe that the specific but reversible Van–AA molecular recognition would be a strategy for dynamic biomaterial fabrication, and the easy-handling merit, ECM-like remoldability, and inherently antibacterial activity involved in this dynamic system will bring insights to biomaterial scaffold design in tissue engineering and regenerative medicine.Open in a separate windowFig. 1.Schematics showing the mechanism of dynamic biointerface and 3D ECM mimics based on a reversible dougong-structured natural receptor–ligand recognition. (A) The Van–AA molecular recognition on bacterial cell wall in nature. (B) Schematic illustration of the dynamic biointerface based on the reversible Van–AA interaction. Reversible bioligand presentation and controllable cell behaviors could be readily realized through the Van–AA interaction. (C) Schematic illustration of the dynamic hydrogels with remoldable network structure and its application in tissue repair. 相似文献
78.
目的探讨同期三镜(腹腔镜、胆管镜、十二指肠镜)、扩张导管(逐级扩张导管、球囊导管)、气囊鼻胆管(LCDND)治疗胆囊结石、胆总管结石、合并十二指肠乳头部梗阻的可行性。方法回顾性分析2010年11月至2016年12月期间,符合入选标准的59例胆囊结石、胆总管结石、合并十二指肠乳头部梗阻患者的临床资料。结果腹腔镜下切除胆囊、胆管镜探查取石59例。逐级导管扩张乳头并留置气囊鼻胆管71.2%(42/59),球囊导管扩张乳头并留置气囊鼻胆管3.4%(2/59),球囊导管取石和扩张乳头并留置气囊鼻胆管3.4%(2/59),十二指肠镜乳头切开并留置气囊鼻胆管20.3%(12/59),中转为开腹胆总管探查取石并留置T形管1.7%(1/59)。术后无残石,胆汁漏2例(3.4%),轻症胰腺炎1例(1.7%)。无肠穿孔、胆管穿孔、大出血、重症胰腺炎等并发症,无死亡。术后总并发症发生率为5.1%(3/59)。结论从本研究对本医院有限病例进行初步研究发现,只要病例选择合适,LCDND治疗胆囊结石、胆总管结石、合并十二指肠乳头部梗阻是可行、有效和安全的。 相似文献
79.
所剑 《中华普外科手术学杂志(电子版)》2015,(2):102
应用电钩沿横结肠与大网膜附着处分离大网膜分别至结肠脾曲及结肠肝区。用超声刀沿胰腺被膜分离,至胰腺上缘显露近脾门处的脾动静脉主干向脾门解剖,清扫第10、11组淋巴结;显露胃网膜左血管根部并离断,向上离断部分胃短血管后,裸化胃大弯,清扫第4组淋巴结。沿胰腺下缘胰后间隙解剖,显露肠系膜上静脉,清扫14v组淋巴结,于胃网膜右静脉汇入胃结肠静脉干处夹闭,显露胃网膜右动脉根部并夹闭,清扫第6组淋巴结。沿胰腺上缘打开胃胰皱襞进入胰后间隙解剖肝总动脉及腹腔动脉干,游离并显露胃左动、静脉,脾动脉及部分肝总动脉,根部切断胃左动、静脉,清扫7、8、9组淋巴结。显露肝总动脉,清扫第8a组淋巴结,显露肝固有动脉,显露胃右动脉根部,夹闭切断胃右动脉,清扫第5、12组淋巴结。沿小网膜与胃小弯前壁附着处切除小网膜,裸化胃壁,清扫第3、5组淋巴结。 相似文献
80.
目的:探讨前后路联合手术治疗髋臼双柱骨折的效果并分析影响疗效的相关因素。方法:2007年8月至2009年7月收治髋臼双柱骨折患者19例,男13例,女6例;年龄27~52岁,平均39.6岁。高位双柱骨折11例,低位双柱骨折8例,双柱骨折累及骶髂关节1例。受伤至手术时间4~11 d,平均5.8 d。患者均采用前后联合入路手术,重建钢板和螺钉内固定。结果:除1例死亡外本组全部获随访,随访时间12~18个月,平均13.6个月。关节功能根据Harris评分标准,术后功能优9例,良7例,可2例。结论:经前后路联合切开复位内固定治疗髋臼双柱骨折疗效满意。 相似文献