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1.
目的总结23例乳腺派杰氏(Paget’s)病患者的诊断及治疗。方法收集我院自1984~2004年23例经病理确诊的乳腺Paget’s病例,通过对病人的临床资料及治疗方法的分析,总结该病的诊治经验。结果乳腺Paget’s病以慢性乳头皮肤改变为主要特点,钼靶X线多显示导管区恶性改变。细胞学检查见到Paget’s细胞。术后7例失访,余16例随访时间最长13年,最短6月,其中3例出现术后远处转移。结论早期诊断及手术为主的综合治疗预后较佳。  相似文献   
2.
目的:探讨MMP-3与TIMP-1在形成肝细粒棘球蚴周围纤维囊壁中的作用.方法:应用免疫组化技术检测基质金属蛋白酶-3(MMP-3)与金属蛋白酶抑制因子-1(TIMP-1)在30例肝细粒棘球蚴周围纤维囊壁的表达.结果:MMP-3、TIMP-1在肝细粒棘球蚴周围纤维囊壁中呈现特异性分层表达,MMP-3、TIMP-1的阳性细胞在外囊中的表达率分别为10%(3/30)、13.3%(4/30).靠近肝实质侧的外膜中MMP-3、TIMP-1的阳性细胞表达率分别为80%(24/30)、90%(27/30).在两层中表达的差异均有显著意义(P<0.01).肝细粒棘球蚴外膜及周围肝组织中MMP-3、TIMP-1的表达两者呈负相关(P<0.01).结论:肝包虫周围纤维性囊壁可分为内层和外层,且各自形成机制不同;MMP-3、TIMP-1与肝实质侧纤维囊壁的形成有密切关系.  相似文献   
3.
目的 探讨雷公藤甲素对U251细胞自噬活性的影响及机制.方法 采用四甲基偶氮唑蓝(MTT)法检测雷公藤甲素对U251细胞的增殖抑制率、半数抑制浓度(IC50);免疫荧光化学法测定细胞中LC3-Ⅱ表达,Western blot法测定LC3-Ⅱ/LC3-Ⅰ、Beclin-1、磷酸化P70、磷酸化Erk、磷酸化AKT蛋白的表达.结果 雷公藤甲素作用于U251细胞后,细胞增殖受抑制,24 h的IC50为0.73 μmol/L,48 h的IC50为0.27μmol/L.免疫荧光法测定6、12、24 h后LC3-Ⅱ水平增高;Western blot法测定LC3-Ⅱ水平、LC3-Ⅱ/LC3-Ⅰ比值随时间增高;Beclin-1水平增高,磷酸化P70、磷酸化Erk表达降低、磷酸化AKT无明显变化.结论 雷公藤甲素可抑制U251细胞增殖并促进自噬,并可通过上调Beclin-1表达和抑制mTOR的活性来促进自噬.  相似文献   
4.
建立了高分子溶液雾点线和旋节线的测定方法及其实验装置,测定了环己烷-聚苯乙烯(M_w=190000;M_w/M_n=1.04)、甲基环己烷-聚苯乙烯(M_w=37900;M_w/M_n=1.01)系统的雾点线和旋节线,经与文献数据比较,表明本方法及其装置是可行的。  相似文献   
5.
BackgroundFear extinction alone does not erase the original fear memory. Interventions that enhance extinction can be beneficial for the treatment of fear-related disorders. Repetitive transcranial magnetic stimulation has been shown to improve memory performance. The present study examined the effects of intermittent theta-burst stimulation (iTBS) on fear extinction and the return of fear memory in humans.MethodsNinety-one young healthy volunteers underwent 3 experiments using a randomized controlled experimental design. Participants first acquired fear conditioning, after which they received 30 Hz iTBS before and after extinction training. The iTBS was applied to 1 of 2 targets: the left dorsolateral prefrontal cortex (dlPFC) and the vertex (control). Fear responses were measured 24 hours later and 1 month later.ResultsDuring the spontaneous recovery and reinstatement tests, iTBS of the left dlPFC before and after extinction significantly reduced fear response, whereas iTBS of the vertex had no effect on fear memory performance. This combined approach had a relatively long-lasting effect (i.e., at least 1 month).LimitationsWe did not explore the effect of iTBS of the dlPFC on the expression of fear without extinction training. The neural mechanisms of iTBS with fear extinction to inhibit the fear response are unclear. Our results are preliminary and should be interpreted with caution.ConclusionThe present results showed that 30 Hz iTBS of the left dlPFC enhanced retention of fear extinction. Our study introduces a new intervention for fear memory and suggests that the left dlPFC may be a treatment target for fear-related disorders.  相似文献   
6.
Biphasic contact analysis is essential to obtain a more complete understanding of soft tissue biomechanics; however, only a limited number of studies have addressed these types of problems. In this paper, a theoretically consistent biphasic finite element solution of the 2D axisymmetric human knee was developed, and an augmented Lagrangian method was used to enforce the biphasic continuity across the contact interface. The interaction between the fluid and solid matrices of the soft tissues of the knee joint, the stress and strain distributions within the meniscus, and the changes in stress and strain distributions in the articular cartilage of the femur and tibia after complete meniscectomy were investigated. It was found that (i) the fluid phase carries more than 60% of the load, which reinforces the need for the biphasic model for knee biomechanics; (ii) the inner third and outer two-thirds of the meniscus had different strain distributions; and (iii) the distributions of both maximum shear stress and maximum principal strain in articular cartilage changed after complete meniscectomy – with peak values increasing by over 350%.  相似文献   
7.
With the merits of high safety and energy density, all-solid-state zinc–air batteries possess potential applications in flexible and wearable electronic devices. Especially, the air cathodes with bifunctional catalytic activity, i.e. oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) have been received enormous attention. In this work, we provide a novel phosphorus/nitrogen co-doped and bimetallic metal–organic framework (MOF)-derived cathode configurated with phosphorus-doped bimetallic FeNi alloys and a nitrogen-doped porous carbon layer loaded on graphene (P–FeNi/NC@G). The P–FeNi/NC@G electrode exhibits a superior OER activity with an overpotential of 310 mV at 10 mA cm−2 and an ORR performance with a half-wave potential of 0.81 V. With P–FeNi/NC@G as the air cathode, the integrated all-solid-state rechargeable zinc–air battery presents a high open-circuit voltage of 1.53 V, a high peak power density of 159 mW cm−2, a small charge–discharge voltage gap of 0.73 V at 5 mA cm−2, as well as excellent long-term stability up to 144 cycles. This work not only expands the air cathode materials database but also develops a new co-doped synthesis method that can be utilized to fabricate a cathode with promoted catalytic efficiency, resulting in improved performance for an all-solid-state zinc–air battery.

The bimetallic FeNi-MOFs are employed to fabricate P–FeNi and N–carbon co-doped bifunctional catalyst. Due to the enhanced catalytic performance, the peak power density of all-solid-state zinc–air battery is 159 mW cm−2.  相似文献   
8.
目的 探讨影响血液系统恶性肿瘤患者伏立康唑谷浓度变异的潜在因素。方法 回顾性地收集2015年11月至2017年9月期间进行伏立康唑治疗药物监测的血液系统恶性肿瘤患者的病史信息、临床资料、用药情况和实验室数据等,分析人口学、生理病理、合并用药、CYP2C19基因型等与标准化谷浓度的相关性。结果 研究最终纳入176例患者241例监测数据,结果显示血液系统恶性肿瘤患者伏立康唑标准化谷浓度存在较大变异(范围从0.38-14.72 mg·L-1)。单因素和多因素Logistic回归分析结果提示,CYP2C19 *1/*1(快代谢型)是标准化谷浓度<1.0 mg·L-1的危险因素(OR: 4.445, 95% CI: 1.514–38.449, P: 0.015);C反应蛋白(OR: 2.377, 95% CI: 1.116, 5.063, P: 0.025)、合并使用奥美拉唑(OR: 4.537, 95% CI: 1.716, 14.637, P: 0.018)及CYP2C19 *2/*2,*2/*3和*3/*3(慢代谢型)(OR: 10.199, 95% CI: 2.516, 21.342, P: 0.001)是VCZ标准化谷浓度> 5.5 mg·L-1的危险因素。结论 血液系统恶性肿瘤患者伏立康唑谷浓度变异度高,影响因素多。CYP2C19基因型、合用奥美拉唑、以及患者炎症水平可能是治疗时需考虑的因素。  相似文献   
9.
目的 对52例乳糜血样本实验数据进行分析,为临床检验提供依据。方法 将52例乳糜血实验室检测数据录入Excel 2007表格,分析乳糜血的原因以及清淡饮食后第3、7天乳糜血变化和血脂水平。结果 共计乳糜血52例。其中男性47例,占90.38%;女性5例,占9.62%。空腹时间不足12 h 者49例,占94.23%。空腹时间12 h以上者3例,占5.77%。化验前1 d晚上饱餐肥腻食物45例,占86.54%。前1周内肥腻饮食5例,占9.62%;前1周内清淡饮食2例,占3.85%。清淡饮食3、7 d后,乳糜血样本血浆颜色恢复正常的比例分别为96.15%、98.08%。乳糜血时血总胆固醇和三酰甘油水平增高,清淡饮食3、7 d后血总胆固醇和三酰甘油水平逐渐减低。清淡饮食3、7 d后血总胆固醇和三酰甘油水平与乳糜血时总胆固醇和三酰甘油水平各自比较,差异均有统计学意义(P<0.05)。结论 乳糜血的主要原因是抽血前天晚饭进食肥厚油腻食物,必须高度重视抽血前检查者的准备工作。  相似文献   
10.
Implant loading can create micromotion at the bone–implant interface. The interfacial strain associated with implant micromotion could contribute to regulating the tissue healing response. Excessive micromotion can lead to fibrous encapsulation and implant loosening. Our objective was to characterize the influence of interfacial strain on bone regeneration around implants in mouse tibiae. A micromotion system was used to create strain under conditions of (1) no initial contact between implant and bone and (2) direct bone–implant contact. Pin- and screw-shaped implants were subjected to displacements of 150 or 300 μm for 60 cycles per day for 7 days. Pin-shaped implants placed in five animals were subjected to three sessions of 150 μm displacement per day, with 60 cycles per session. Control implants in both types of interfaces were stabilized throughout the healing period. Experimental strain analyses, microtomography, image-based displacement mapping, and finite element simulations were used to characterize interfacial strain fields. Calcified tissue sections were prepared and Goldner trichrome stained to evaluate the tissue reactions in higher and lower strain regions. In stable implants bone formation occurred consistently around the implants. In implants subjected to micromotion bone regeneration was disrupted in areas of high strain concentrations (e.g. >30%), whereas lower strain values were permissive of bone formation. Increasing implant displacement or number of cycles per day also changed the strain distribution and disturbed bone healing. These results indicate that not only implant micromotion but also the associated interfacial strain field contributes to regulating the interfacial mechanobiology at healing bone–implant interfaces.  相似文献   
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