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101.
The self-assembly of metal–organic frameworks (MOFs) is crucial for the functional design of materials, including energy storage materials, catalysts, selective separation materials and optical crystals. However, oriented self-assembly of MOFs is still a challenge. Herein, we propose a novel strategy to drive oriented self-assembly of MOF polyhedral particles at the water–liquid interface by photoinitiated monomer polymerization. The MOF polyhedral particles self-assemble into ordered close-packed structures with obvious orientation in the polymer film, and the orientation is determined by the casting solvent on the water surface. The prepared large-area MOF polymer films show a Janus structure, containing a MOF monolayer and a polymer layer, and can be easily transferred to a variety of substrates. In addition, mixed MOF particles with different sizes and morphologies can also be assembled by this method. This novel method can be foreseen to provide a powerful driving force for the development of MOF self-assembly and to create more possibilities for utilizing the anisotropic properties of MOFs.

The self-assembly of metal–organic frameworks (MOFs) is crucial for the functional design of materials, including energy storage materials, catalysts, selective separation materials and optical crystals.  相似文献   
102.
Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) is a high-risk disease subtype with a dismal prognosis. Inhibiting BCR-ABL kinase alone is insufficient to eradicate Ph+ALL clones, and alternative BCR-ABL-dependent and -independent pathways need to be targeted as an effective strategy. Our study revealed that the combination of dasatinib and interferon-α showed synergistic activity against Ph+ALL, inducing mitochondrial dysfunction and causing necrosis-like cell lysis. Mechanistic studies showed that the induced cell death was caspase-3-independent. Canonical necroptosis signals, such as RIP1 and MLKL, were not activated; instead, the pyroptosis executor Gasdermin D was upregulated expression and activated. The expression levels of extracellular ATP and IL-1β were also upregulated, both of which are markers of pyroptotic cell death. In a murine Ph+ALL model, the dual drug treatment prolonged the survival of tumor-bearing mice. More importantly, we incorporated the dual drugs to maintenance therapy in 39 patients who were unfit for allogeneic stem cell transplantation (allo-HSCT). The median follow-up was 28.5 months, the 4-year disease-free survival and overall survival rates were 52.2% and 65.2%, respectively. Our data suggest that the combination of dasatinib and interferon-α has potential synergistic activity against Ph+ALL and shows promise as a maintenance therapy for Ph+ALL patients who are unfit for allo-HSCT.  相似文献   
103.
Rationale:This study describes an 8-year-old boy with a C2 fracture and dislocation with a left C2–C3 articular process interlocking and spinal cord injury who underwent open reduction and internal fixation using the posterior cervical approach and achieved satisfactory results.Patient concerns:An 8-year-old boy underwent an emergency transfer from a previous hospital after a car accident.Diagnoses:Axial fracture and dislocation with spinal cord injury (American Spinal Injury Association grade C), traumatic shock, brain contusion, intracranial hemorrhage, mandibular fracture, pulmonary contusion and hemorrhage, left vertebral artery stenosis, and multiple fractures throughout the body. Radiological examination revealed a fracture of the lower edge of the C2 vertebral body, fourth-degree anterior spondylolisthesis of the C2 vertebral body, interlocking of the left C2–C3 articular processes, widening of the C2–C3 vertebral space, and occlusion of the V1 and 2 segments of the left vertebral artery.Interventions:The boy was immediately intubated and transferred to the pediatric intensive care unit for rescue treatment. However, the reduction was unsuccessful with 2 weeks of cranial traction. Thus, an open reduction was performed under general anesthesia. One month after the surgery, the boy was discharged from the hospital on foot after rehabilitation treatment.Outcomes:The boy was discharged from the hospital 1 month after surgery. At the 8-month follow-up, a radiological examination showed that the corrected C2 vertebral body fracture and dislocation were satisfactorily reduced, and the spinal cord was adequately decompressed. The internal fixation position was also good, and the spinal sequence had recovered well. In summary, except for the muscle strength of the right upper limb, which was slightly worse, the other clinical symptoms were significantly improved.Lessons:In treating cervical fracture and dislocation with unilateral facet lock, the posterior open reduction of pedicle screw and lateral mass screw internal fixation achieved satisfactory results. Consequently, treating complex cervical spine injuries in children requires an accurate diagnosis and careful treatment strategy.  相似文献   
104.
不同浸泡时间对浙贝母有效成分提取的影响   总被引:1,自引:0,他引:1  
目的以贝母素甲、贝母素乙作为指标成分,研究不同浸泡时间对浙贝母有效成分提取的影响,考察比较合理的煎煮方法。方法采用高效液相色谱一蒸发光散射器(HPLC—ELSD)法检测,DionexAcclaimC18色谱柱(250mm×4.6mm,5μm),流动相为乙腈-0.1%二乙胺(70:30),流速为1.0mL/min;ELSD条件为漂移管温度42℃,载气(高纯N2)流速1.0L/min。结果不同浸泡时间对浙贝母饮片有效成分提取量差异明显。随着饮片浸泡时间的延长,煎煮后药渣的白心率降低,而煎膏得率及其有效成分提取量均增高。结论浙贝母饮片用常规煎煮方法很难煮透,至少应先浸泡1h,才能使有效成分较好地溶出,发挥更好的药效。  相似文献   
105.
Postnatal ontogeny of dopamine D2 receptors in rat striatum   总被引:1,自引:0,他引:1  
Studies of the ontogeny of dopamine D2 receptors in rat striatum were carried out using [3H]spiroperidol as ligand in the presence of 30 nM ketanserin. D2 receptors increased with age, and saturation studies indicated that this was due to an increase in receptor density (Bmax) and not to a change in affinity (KA). By 21 days of age, receptor density had reached adult levels. Hill plots indicated no cooperativity in the binding from 7 to 21 days of age. Pharmacologically, receptors at 7, 14 and 21 days of age were similar to those of adult rats, exhibiting characteristics of dopamine D2 receptors. These studies provide a basic analysis of dopamine D2 receptors in rat striatum during early postnatal development.  相似文献   
106.
卜宪敏  郑智勇  王晨  曾玲  余英豪 《解剖学杂志》2007,30(1):28-30,F0003
目的:观察补体成分在淋巴组织中的表达,探讨不同发育阶段淋巴滤泡中补体激活与免疫球蛋白沉积及滤泡树突状细胞之间的关系。方法:采用免疫组化方法对淋巴组织标本进行IgG、IgM、IgA、C3c、C4c、C1q和C4d标记,同时对其部分标本进行双标染色。结果:淋巴组织次级滤泡的Ⅰ~Ⅳ期的生发中心才出现不同程度的IgG、IgM、IgA、C3c、C4c、C1q、C4d阳性表达;免疫球蛋白与补体成分重叠沉积,并呈不规则网线状包绕在滤泡树突状细胞周围。其中以C4d的阳性表达最强。结论:淋巴滤泡生发中心有大量免疫球蛋白和补体成分围绕滤泡树突状细胞沉积,可能与中心淋巴细胞的发育和选择有关。  相似文献   
107.
Scattering can seriously affect the highly sensitive detection and quantitative analysis of chemical substances in scattering media and becomes a significant challenge for in vivo application of Raman spectroscopy. In this study, we demonstrated a proof of concept for using the self-reconstructing Bessel beam for Raman spectroscopic sensing of the chemicals in the handmade scattering media and biological tissue slices. The homebuilt Bessel beam Raman spectroscopy (BRS) was capable of accurately detecting the Raman spectra of the chemicals buried in the scattering media, and had a superiority in quantitative analysis. The feasibility of the developed technique was verified by detecting the Raman spectra of pure samples in air. Compared with the spectra acquired by the Gaussian beam Raman spectroscope, the performance of the BRS system in terms of Raman spectrum detection and Raman peak recognition was confirmed. Subsequently, by employing the technique for the detection of acetaminophen buried in the scattering media, the application of the new technology in detecting and quantitating the chemicals in the scattering media were underlined, offering greater detection depth and better linear quantification capability than the conventional Gaussian beam Raman spectroscopy. Finally, we explored the potential of the BRS system for chemical sensing of acetaminophen in biological tissue slices, indicating a significant development towards the evaluation of drug in vivo.  相似文献   
108.
目的 观察模拟失重对人下肢脂肪体积的影响,验证磁共振水脂分离成像技术在测量人下肢脂肪容积中的可行性.方法 14名男性健康志愿者,-6°头低位卧床30 d,使用磁共振水脂分离成像(Dixon)技术采集卧床前后的下肢横断面解剖图像,测量卧床前后下肢脂肪体积.结果 与卧床前相比,卧床后所有志愿者下肢总脂肪体积及大腿段脂肪体积显著增加(P<0.001);小腿段脂肪体积呈增加趋势,但无统计学差异(P>0.05).结论 使用MRI水脂分离成像可以清晰地显示卧床前后下肢脂肪体积的变化;-6°头低位卧床30 d后下肢脂肪体积明显增加.  相似文献   
109.
姜恒  韩威  刘彦华  曾德权  黎敏  赵燕  马骄 《西南国防医药》2011,21(11):1167-1169
目的介绍运用热乙醇法提取高纯度猪血白蛋白的改良工艺流程。方法采用热乙醇法,在合适的恒温时间和pH值的条件下,分离提纯猪血清白蛋白。结果猪血白蛋白的纯度〉97%,回收率〉80%。检测结果显示,其理化指标均符合《中国生物制品规程2000年版》的要求,适合扩大到中试生产。结论该法与低温乙醇法、利凡诺法和盐析法相比,具有工艺简单、成本低、纯度和回收率高的特点。  相似文献   
110.
Osteosarcoma is a kind of bone tumor with highly proliferative and invasive properties, a high incidence of pulmonary metastasis and a poor prognosis. Chemotherapy is the mainstay of treatment for osteosarcoma. Currently, there are no molecular targeted drugs approved for osteosarcoma treatment, particularly effective drugs for osteosarcoma with pulmonary metastases. It has been reported that fibroblast activation protein alpha (FAPα) is upregulated in osteosarcoma and critically associated with osteosarcoma progression and metastasis, demonstrating that FAPα-targeted agents might be a promising therapeutic strategy for osteosarcoma. In the present study, we reported that the FAPα-activated vinblastine prodrug Z-GP-DAVLBH exhibited potent antitumor activities against FAPα-positive osteosarcoma cells in vitro and in vivo. Z-GP-DAVLBH inhibited the growth and induced the apoptosis of osteosarcoma cells. Importantly, it also decreased the migration and invasion capacities and reversed epithelial–mesenchymal transition (EMT) of osteosarcoma cells in vitro and suppressed pulmonary metastasis of osteosarcoma xenografts in vivo. Mechanistically, Z-GP-DAVLBH suppressed the AXL/AKT/GSK-3β/β-catenin pathway, leading to inhibition of the growth and metastatic spread of osteosarcoma cells. These findings demonstrate that Z-GP-DAVLBH is a promising agent for the treatment of FAPα-positive osteosarcoma, particularly osteosarcoma with pulmonary metastases.KEY WORDS: Osteosarcoma, Fibroblast activation protein alpha, Growth, Pulmonary metastasis, Vinblastine prodrug, AXL, β-Catenin  相似文献   
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