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1.
《中国化学快报》2020,31(12):3027-3040
The tumor microenvironment (TME) significantly influences cancer evolution and therapeutic efficacy. Targeting biofunctional molecules to the TME has long been appreciated as a means of raising local drug concentrations and reducing systemic toxicities. The booming nanotechnology field has realized the importance of cathepsin B to derive a variety of intelligent enzyme-responsive nanosized drug delivery systems (nanoDDS) to improve treatment responses and clinical outcomes. In this tutorial review, after introducing the molecular structure and physiological/pathological functions of cathepsin B, the outstanding achievements of cathepsin B-responsive nanoplatforms in the precise diagnosis, targeted therapy, and synergistic theranostics of malignant tumors are systematically described. Finally, the challenges of enzyme-substrate incompatibility, low diagnostic sensitivity, mass production and biocompatibility of multifunctional nanoDDS are considered in order to successfully promote them to clinical applications 相似文献
2.
《Tetrahedron》2017,73(19):2824-2830
A novel near infrared ratiometric fluorescent chemosensor based on triphenylamine, thiophene and benzothiadiazole has been developed. The emission wavelength of sensor DTPAT-BT-S was in the near infrared region. The wavelength changed from 656 nm to 723 nm, and got a rather long stokes shift about 170 nm. The sensor showed a very high selectivity towards Hg2+ ions. 相似文献
3.
An incompressible fluid is in motion after injection in the space between two parallel porous discs that can move away or come closer along the same axis passing perpendicular to the midpoints of their respective surfaces. The desire of well describing the incompressible fluid flow patterns and the fact that the velocity field of the axisymmetric flow has two components lead to introduce the stream function in the governing equations. A similarity method is applied to transform the vorticity equation satisfied by the stream function into a nonlinear ordinary differential equation. Thus, the analysis is restricted to solving a two-point boundary-value problem containing two control parameters, notably the Reynolds number and a nondimensional parameter representing the measure of the increase or the decrease in volume of the flow domain. Among the main results, it is found that, the high expansion in volume of the flow domain causes flow reversal for low values of the injection Reynolds number, while the contraction in volume of the flow domain creates a linear behavior of the axial velocity for a small injection Reynolds number and a flattening of the radial velocity profile for all the Reynolds numbers. 相似文献
4.
Magnetism and giant magnetocaloric effect in rare-earth-based compounds R_3BWO_9(R = Gd,Dy, Ho) 下载免费PDF全文
《中国物理 B》2021,30(7):77501-077501
The magnetism and magnetocaloric effect(MCE) of rare-earth-based tungstate compounds R_3 BWO_9(R=Gd,Dy,Ho) have been studied by magnetic susceptibility,isothermal magnetization,and specific heat measurements.No obvious long-range magnetic ordering can be found down to 2 K.The Curie-Weiss fitting and magnetic susceptibilities under different applied fields reveal the existence of weak short-range antiferromagnetic couplings at low temperature in these systems.The calculations of isothermal magnetization exhibit a giant MCE with the maximum changes of magnetic entropy being 54.80 J/kg-K at 2 K for Gd_3 BWO_9,28.5 J/kg-K at 6 K for Dy_3 BWO_9,and 29.76 J/kg-K at 4 K for Ho_3 BWO_9,respectively,under a field change of 0-7 T.Especially for Gd_3 BWO_9,the maximum value of magnetic entropy change(-ΔS_M~(max)) and adiabatic temperature change(-ΔT_(ad)~(max)) are 36.75 J/kg·K and 5.56 K for a low field change of 0-3 T,indicating a promising application for low temperature magnetic refrigeration. 相似文献
5.
A new metal complex[MnL2](NO3)2·CH3CN(1) was synthesized by reaction of 4’-4-(l,2,4-triazol-l-yl)phenyl -2,2’:6’,2"-terpyridine(L) with manganese nitrate.The structure of the complex was determined by X-ray crystallography.The results of UV-vis studies showed that the complex exhibits colorimetric sensing ability for Fe3+,which can be observed by naked eye. 相似文献
6.
A generalization of Zellner’s balanced loss function is proposed. General admissibility in a general multivariate linear model is investigated under the generalized balanced loss function. And the sufficient and necessary conditions for linear estimators to be generally admissible in classes of homogeneous and nonhomogeneous linear estimators are given, respectively. 相似文献
7.
The composition of soluble algal products was visualized by a fingerprint analytical method. 相似文献
8.
In this work, a novel scheme is proposed to realize joint remote preparation regarding a class of four-qubit cluster-like entangled states based on optimal positive operator-valued measurements. To obtain the preparation of desired states, two tripartite non-maximally entangled states are taken as quantum channels, and devoted to building the robust connections amongst the states’ senders and receiver. It turns out that the present scheme enables one to achieve joint remote state preparation with certain success probability (SP) and unit fidelity. Moreover, several nontrivial issues are discussed, including the improvement of SP and the correlation between SP and the employed channels. 相似文献
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10.
A novel configuration of fiber ring laser acoustic sensor, which adopts single-mode fiber as sensing element, is proposed and demonstrated. Linewidth less than 1 kHz is achieved by introducing a segment of erbium-doped fiber in the reflecting arm as saturable absorber. A polarization independent unbalanced Michelson interrogation interferometer and phase generated carrier demodulation technique are adopted to recover signal. Experiments demonstrate that the phase sensitivity is 0.018 rad/nm in good linearity and equivalent minimum detect able length change reaches 19.1 pm. 相似文献