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991.
Peptide-based probes play prominent roles in biomedical research due to their promising properties such as high biocompatibility, fast excretion, favorable pharmacokinetics as well as easy and robust preparation. Considering the translation of imaging probes into clinical applications, peptide-based probes remain to be the most desirable and optimal candidates. 相似文献
992.
993.
A one-pot,four-component reaction of ethyl acetoacetate,hydrazine hydrate,aldehydes,and malononitrile was discussed using Lewis acid catalyst morpholine triflate (MorT) to afford a series of dihydropyrano[2,3-c] pyrazoles,which were generally catalyzed by organic alkalis.Moderate to excellent yields,no chromatographic purification,and evasion of environmentally hazardous solvents in the reaction process make this protocol very useful for academia and industry. 相似文献
994.
The aim of this study was to evaluate the accuracy in the Normal and DFD classification in Nellore beef using a bench-top hyperspectral imaging system. A hyperspectral imaging system (λ = 928–2524 nm) was used to collect hyperspectral images of the Longissimus thoracis et lumborum (n = 78) of Nellore cattle. The images were processed, being selected region of interest and extracted spectra image and were selected the wavelengths considered most important for the treats evaluated. Six linear discriminant models were developed to classify beef samples on Normal and DFD. The model using all wavelengths associated with the reflectance and absorbance spectrum transformed with the pretreatment 2nd derivative resulted in an overall accuracy of 93.6% for both pretreatments. In this configuration, the model was able to classify correctly 73 samples from a total of 78 samples. The results demonstrate that the hyperspectral imaging system may be considered a viable technology for beef classification on Normal and DFD. 相似文献
995.
Ultrasound and microbubbles-mediated drug delivery has become a promising strategy to promote drug delivery and its therapeutic efficacy. The aim of this research was to assess the effects of microbubbles (MBs)-combined low-intensity pulsed ultrasound (LPUS) on the delivery and cytotoxicity of curcumin (Cur) to human breast cancer MDA-MB-231 cells. Under the experimental condition, MBs raised the level of acoustic cavitation and enhanced plasma membrane permeability; and cellular uptake of Cur was notably improved by LPUS–MBs treatment, aggravating Cur-induced MDA-MB-231 cells death. The combined treatment markedly caused more obvious changes of cell morphology, F-actin cytoskeleton damage and cell migration inhibition. Our results demonstrated that combination of MBs and LPUS may be an efficient strategy for improving anti-tumor effect of Cur, suggesting a potential effective method for antineoplastic therapy. 相似文献
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997.
Inside Cover: Hierarchical NiCo2O4 Hollow Microcuboids as Bifunctional Electrocatalysts for Overall Water‐Splitting (Angew. Chem. Int. Ed. 21/2016) 下载免费PDF全文
998.
Excellent Lithium Storage Materials Consisting of Highly Distributed Fe3O4 Quantum Dots on Commercially Available Graphite Nanoplates 下载免费PDF全文
999.
Keli An Xuqian Deng Hongli Chi Yuchao Zhang Yan Li Dr. Ming Cheng Dr. Zhigang Ni Zhi Yang Dr. Chao Wang Jinling Chen Dr. Jianbo Bai Chunyan Ran Yong Wei Juan Li Dr. Penghui Zhang Dr. Feng Xu Dr. Weihong Tan 《Angewandte Chemie (International ed. in English)》2023,62(39):e202306824
Proteolysis Targeting Chimeras (PROTACs) represent a promising therapeutic modality to address undruggable and resistant issues in drug discovery. However, potential on-target toxicity remains clinically challenging. We developed a generalized caging strategy to synthesize a series of stimuli-responsive PROTACs (sr-PROTACs) with diverse molecular blocks bearing robust and cleavable linkers, presenting “turn on” features in manipulating protein degradation. By leveraging pathological cues, such as elevated ROS, phosphatase, H2S, or hypoxia, and external triggers, such as ultraviolet light, X-Ray, or bioorthogonal reagents, we achieved site-specific activation and traceless release of original PROTACs through de-caging and subsequent self-immolative cleavage, realizing selective uptake and controlled protein degradation in vitro. An in vivo study revealed that two sr-PROTACs with phosphate- and fluorine-containing cages exhibited high solubility and long plasma exposure, which were specifically activated by tumor overexpressing phosphatase or low dosage of X-Ray irradiation in situ, leading to efficient protein degradation and potent tumor remission. With more reactive biomarkers to be screened from clinical practice, our caging library could provide a general tool to design activatable PROTACs, prodrugs, antibody-drug conjugates, and smart biomaterials for personalized treatment, tissue engineering or regenerative medicine. 相似文献
1000.
Yuxiong Wang Guang Hong Yaoyu Zhang Prof. Yue Liu Dr. Wanglai Cen Prof. Lianzhou Wang Prof. Zhongbiao Wu 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310525
C−H dissociation and C−C coupling are two key steps in converting CH4 into multi-carbon compounds. Here we report a synergy of Au and Ag to greatly promote C2H6 formation over Au1Ag single-atom alloy nanoparticles (Au1Ag NPs)-modified ZnO catalyst via photocatalytic oxidative coupling of methane (POCM) with O2 and H2O. Atomically dispersed Au in Au1Ag NPs effectively promotes the dissociation of O2 and H2O into *OOH, promoting C−H activation of CH4 on the photogenerated O− to form *CH3. Electron-deficient Au single atoms, as hopping ladders, also facilitate the migration of electron donor *CH3 from ZnO to Au1Ag NPs. Finally, *CH3 coupling can readily occur on Ag atoms of Au1Ag NPs. An excellent C2H6 yield of 14.0 mmol g−1 h−1 with a selectivity of 79 % and an apparent quantum yield of 14.6 % at 350 nm is obtained via POCM with O2 and H2O, which is at least two times that of the photocatalytic system. The bimetallic synergistic strategy offers guidance for future catalyst design for POCM with O2 and H2O. 相似文献