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排序方式: 共有239条查询结果,搜索用时 18 毫秒
141.
Kashif Rafiq Najeeb Ur Rehman Sobia Ahsan Halim Majid Khan Ajmal Khan Ahmed Al-Harrasi 《Molecules (Basel, Switzerland)》2022,27(3)
Carbonic anhydrase-II (CA-II) is strongly related with gastric, glaucoma, tumors, malignant brain, renal and pancreatic carcinomas and is mainly involved in the regulation of the bicarbonate concentration in the eyes. With an aim to develop novel heterocyclic hybrids as potent enzyme inhibitors, we synthesized a series of twelve novel 3-phenyl-β-alanine 1,3,4-oxadiazole hybrids (4a–l), characterized by 1H- and 13C-NMR with the support of HRESIMS, and evaluated for their inhibitory activity against CA-II. The CA-II inhibition results clearly indicated that the 3-phenyl-β-alanine 1,3,4-oxadiazole derivatives 4a–l exhibited selective inhibition against CA-II. All the compounds (except 4d) exhibited good to moderate CA-II inhibitory activities with IC50 value in range of 12.1 to 53.6 µM. Among all the compounds, 4a (12.1 ± 0.86 µM), 4c (13.8 ± 0.64 µM), 4b (19.1 ± 0.88 µM) and 4h (20.7 ± 1.13 µM) are the most active hybrids against carbonic CA-II. Moreover, molecular docking was performed to understand the putative binding mode of the active compounds. The docking results indicates that these compounds block the biological activity of CA-II by nicely fitting at the entrance of the active site of CA-II. These compounds specifically mediating hydrogen bonding with Thr199, Thr200, Gln92 of CA-II. 相似文献
142.
Qingyun Jiang Tingting Han Haijun Ren Aziz Ur Rehman Aziz Na Li Hangyu Zhang Zhengyao Zhang Bo Liu 《Electrophoresis》2020,41(16-17):1509-1516
Bladder cancer is the fourth most common cancer in men, and it is becoming a prevalent malignancy. Most of the regular clinical examinations are prompt evaluations with cystoscopy, renal function testing, which require high-precision instrument, well-trained operators, and high cost. In this study, a microfluidic paper-based analytical device (μPAD) was fabricated to detect nuclear matrix protein 22 (NMP22) and bladder cancer antigen (BTA) from the urine samples. Urine samples were collected from 11 bladder cancer patients and 10 well-beings as experiment and control groups, respectively, to verify the working efficiency of μPAD. A remarkable checkout efficiency of up to 90.91% was found from the results. Meanwhile, this method is feasible for home-based self-detection from urine samples within 10 min for the total process, which provides a new way for quick, economical, and convenient tumor diagnosis, prognosis evaluation, and drug response. 相似文献
143.
Hafeez Ullah Khairun Azizi Mohd Azizli Zakaria B. Man Mokhtar B. Che Ismail Siaf Ur Rehman Muhammed Irfan Khan 《Polymer Science Series B》2018,60(1):20-34
This article aims to address the problems associated with the encapsulation of oxirane ring containing compounds in poly(urea-formaldehyde) (PUF) shell for application in self-healing composite systems. The main objectives were to produce non-agglomerated, stable microcapsules, and to control the pH drop during the encapsulation via oil-in-water emulsion polymerization. In the modified method; two stage additions of urea and formaldehyde monomers, core to shell ratio, weight percent and combination of two surfactants/emulsifiers were altered to produce the desired product. Analysis was done with optical microscope (OM), scanning electron microscopy (SEM), FTIR, particle size analyzer, and thermogravimetric analysis (TGA). The pH drop was confirmed by using a common epoxy resin, an epoxy functionalized polydimethylsiloxane (E-PDMS), and epoxidized palm oil (EPO) as cores. The modified oil-in-water emulsion polymerization of PUF was effective in preventing the pH drop during the encapsulation and a product stable for more than 3 months with less agglomeration was produced. The method produced microcapsules having diameters less than 100 μm at lower agitation rates. The modified method is only applicable to epoxy resin and not for compounds like amine hardeners. The use of stable microcapsules in self-healing coatings can lead towards cost reduction implied for repair and maintenance purposes. 相似文献
144.
Near‐IR BODIPY Dyes à la Carte—Programmed Orthogonal Functionalization of Rationally Designed Building Blocks
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Dr. Cesar F. A. Gómez‐Durán Ixone Esnal Dr. Ismael Valois‐Escamilla Arlette Urías‐Benavides Dr. Jorge Bañuelos Prof. Iñigo López Arbeloa Dr. Inmaculada García‐Moreno Prof. Eduardo Peña‐Cabrera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1048-1061
Herein, we report the synthesis of polyfunctional BODIPY building blocks suitable to be subjected to several reaction sequences with complete chemoselectivity, thereby allowing the preparation of complex BODIPY derivatives in a versatile and programmable manner. The reactions included the Liebeskind–Srogl cross‐coupling reaction (LSCC), nucleophilic aromatic substitution (SNAr), Suzuki, Sonogashira, and Stille couplings, and a desulfitative reduction of the MeS group. This novel synthetic protocol is a powerful route to design a library of compounds with tailored photophysical properties for advanced applications. In this context, it is noteworthy that it offers a straightforward and cost‐effective strategy to shift the BODIPY emission deep into the near‐infrared spectral region while retaining high fluorescence quantum yields as well as highly efficient and stable laser action. These new dyes outperform the lasing behaviour of dyes considered as benchmarks over the red spectral region, overcoming the important drawbacks associated with these commercial laser dyes, namely low absorption at the standard pump wavelengths (355 and 532 nm) and/or poor photostability. 相似文献
145.
In this paper, the approximate solutions to the eighth-order boundary-value problems are presented using the reproducing kernel space method. The procedure is applied on both linear and nonlinear problems. Searching least value (SLV) method is investigated for nonlinear boundary value problems. The argument is based on the reproducing kernel space $W_{2}^{9}[a,b]$ . The approach provides the solution in the form of a convergent series with easily computable components. Analytical results are given for several examples to illustrate the implementation and efficiency of the method. A comparison of the results obtained by the present method with results obtained by other methods reveals that the present method is more effective and convenient. 相似文献
146.
N. A. Bulychev V. N. Fomin E. B. Malyukova N. B. Ur’ev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(12):2160-2165
The adsorption of hydrophilic ethylhydroxyethylcellulose (EHEC) polymer on the surface of TiO2 and Fe2O3 inorganic pigments under the action of intense mechanical actions was studied by infrared spectroscopy. Mechanoactivation
methods included ultrasonic action and mechanical treatment at sonic frequencies. Intense action on TiO2 and Fe2O3 aqueous disperse systems activated the surface of inorganic oxides and intensified the adsorption of the polymer. It also
caused the formation of adsorption-solvation EHEC layers with increased densities, which determined the sedimentation stability
of disperse systems. 相似文献
147.
148.
D. Montanari S. Leoni D. Mengoni G. Benzoni N. Blasi G. Bocchi P.F. Bortignon A. Bracco F. Camera G. Colò A. Corsi F.C.L. Crespi B. Million R. Nicolini O. Wieland J.J. Valiente-Dobon L. Corradi G. de Angelis F. Della Vedova E. Fioretto A. Gadea D.R. Napoli R. Orlandi F. Recchia E. Sahin R. Silvestri A.M. Stefanini R.P. Singh S. Szilner D. Bazzacco E. Farnea R. Menegazzo A. Gottardo S.M. Lenzi S. Lunardi G. Montagnoli F. Scarlassara C. Ur G. Lo Bianco A. Zucchiatti M. Kmiecik A. Maj W. Meczynski A. Dewald Th. Pissulla G. Pollarolo 《Physics letters. [Part B]》2011
149.
H. Ur Rehman S. Ahmad H. Ajaz M. Hanif M. Altaf H. Stoeckli-Evans 《Journal of Structural Chemistry》2011,52(1):160-165
A polymeric silver(I) complex, bis(N-methylthiourea)silver(I) nitrate, {[Ag(Metu)2]NO3}
n
is prepared and its crystal structure is determined. The compound crystallizes in the monoclinic C2/c space group. In the structure, distorted AgS4 tetrahedra are linked through the sulfur atoms of the Metu ligand to form isolated infinite chains of the type [Ag(SR)2]
n
n+. The cationic chains are separated from each other by nitrate ions that do not coordinate to the metal ion. The chains are
bridged via N-H...O hydrogen bonds involving the nitrate ions. The complex exhibits an Ag—Ag separation of ∼3.21 ? indicating
the existence of significant argentophilic interactions. An upfield shift in the >C=S resonance of Metu in 13C NMR and downfield shift in the N-H resonance in 1H NMR are consistent with sulfur coordination to silver(I). 相似文献
150.
A. Görgen E. Clément A. Chatillon A. Dewald W. Korten Y. Le Coz N. Mărginean B. Melon R. Menegazzo O. Möller Ch. Theisen D. Tonev C. A. Ur K. O. Zell 《The European Physical Journal A - Hadrons and Nuclei》2005,26(2):153-157
Lifetimes of excited states in the ground-state bands of 74Kr and 76Kr were measured using the recoil-distance Doppler-shift and the differential decay curve methods. The states were populated
in the 40Ca(40Ca, α2p) and 40Ca(40Ca, 4p) reactions. Gamma rays were detected with the GASP array which was coupled to the Cologne Plunger device. The results resolve
discrepancies between earlier lifetime measurements and a recent Coulomb excitation experiment. Experimental transition rates
are compared to theoretical calculations. The results support a strong mixing between prolate and oblate configurations for
the low-spin states, and represent an important basis for the interpretation and understanding of the shape coexistence phenomenon
in this mass region. 相似文献