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141.
In recent years, near-infrared spectroscopy (NIRS) has gained importance for non-invasive or minimally invasive diagnostic
applications in cancer. This technology is based on differences of endogenous chromophores between cancer and normal tissues
using either oxy-haemoglobin or deoxy-haemoglobin, lipid or water bands, or a combination of two or more of these as diagnostic
markers. These marker bands provide a basis for the diagnosis and therapy monitoring of several cancers. Various applications
also use advances in NIR fluorescence spectroscopy which is based on exogenous contrast-enhancing agents. In this review the
literature published during the last seven years has been assessed. It will provide an overview on the importance of the NIRS
tools in cancer pathology, and in the near future it is envisaged to play a crucial role in cancer diagnosis, treatment decisions,
and defining therapeutic drug levels. 相似文献
142.
Prasad Mishra G Venkata Ramana G Venkateswara Rao B 《Chemical communications (Cambridge, England)》2008,(29):3423-3425
A new, efficient and highly diastereoselective approach for the synthesis of 1,2,3,5-tetraacetylcarba-alpha-D-lyxofuranose from D-ribose is reported via one-pot conversion of to using Tebbe reagent which involves a cascade reaction sequence of methylenation, cleavage of isopropyl group, carbocyclization and again methylenation. 相似文献
143.
Venkatapuram Padmavathi Annaji Venkata Nagendra Mohan Konda Mahesh 《Journal of heterocyclic chemistry》2008,45(4):1131-1138
144.
Venkatapuram Padmavathi Kaveti Sudheer Dandu Rangayapalle Chinna Venkata Subbaiah Konda Mahesh 《Journal of heterocyclic chemistry》2008,45(2):513-519
145.
Mudiganti NV Claessens S Habonimana P De Kimpe N 《The Journal of organic chemistry》2008,73(10):3867-3874
An efficient synthesis of naturally occurring compounds isolated from Pentas longiflora, cis-3,4-dihydroxy-3,4-dihydromollugin 2, and trans-3,4-dihydroxy-3,4-dihydromollugin 3 is described. The O-protected mollugins were dihydroxylated using OsO4 to achieve the corresponding cis-dihydroxy derivatives in excellent yield. The synthesis of trans-3,4-dihydroxy-3,4-dihydromollugin was achieved using Oxone in good yield. A mechanism for the formation of cis-3,4-dihydroxymollugin acetonide from the reaction of mollugin with Oxone is proposed. 相似文献
146.
Ramana CV Khaladkar TP Chatterjee S Gurjar MK 《The Journal of organic chemistry》2008,73(10):3817-3822
A flexible approach for total syntheses of possible multiplolide A diastereomers establishing the relative and absolute configuration is documented. The adopted strategy features ring-closing metathesis (RCM) as the key reaction and screening of a set of substrates for the feasibility of RCM in general and for the requisite E-configuration of ring olefin in particular. Selective protecting groups manipulation prior to the assembly of the central macrocyclic core was instrumental in installing the epoxide functionality on a fully deprotected nonenolide at the end of the synthesis. 相似文献
147.
Electrospinning is a well-known technique since 1544 to fabricate nanofibers using different materials like polymers, metals oxides, proteins, and many more. In recent years, electrospinning has become the most popular technique for manufacturing nanofibers due to its ease of use and economic viability. Nanofibers have remarkable properties like high surface-to-volume ratio, variable pore size distribution (10–100 nm), high porosity, low density, and are suitable for surface functionalization. Therefore, electrospun nanofibers have been utilized for numerous applications in the pharmaceutical and biomedical field like tissue engineering, scaffolds, grafts, drug delivery, and so on. In this review article, we will be focusing on the versatility, current scenario, and future endeavors of electrospun nanofibers for various biomedical applications. This review discusses the properties of nanofibers, the background of the electrospinning technique, and its emergence in chronological order. It also covers the various types of electrospinning methods and their mechanism, further elaborating the factors affecting the properties of nanofibers, and applications in tissue engineering, drug delivery, nanofibers as biosensor, skin cancer treatment, and magnetic nanofibers. 相似文献
148.
Vydyula Pavan Kumar Iragavarapu Suryanarayana Yadavalli Venkata Durga Nageswar Kakulapati Rama Rao 《Helvetica chimica acta》2008,91(4):753-758
Two modified β‐cyclodextrins, H‐2 and H‐3 , having a flexible appended moiety were studied for the chiral discrimination of the enantiomers of various amino acids by means of fluorescence as signaling option. These hosts quenched the fluorescence intensities of amino acids upon binding. The d‐ enantiomers were better recognized by these hosts. The association constants (Ks) and enantioselectivity factors (α) of the host?guest complexes were calculated. 相似文献
149.
Venkata Swamy Tangeti Ramesh Varma K. G. V. Siva Prasad K. V. V. V. Satyanarayana 《合成通讯》2016,46(7):613-619
An efficient method was developed for the synthesis of dihydrofuran substituted coumarin from a one-pot, four-component reaction of 2-hydroxy aromatic aldehydes, 6-methyl, 4-hydroxy pyranone, aromatic aldehyde, and pyridinium ylide in the presence of tri-ethylamine under microwave irradiation. The reaction proceeds under solvent-free conditions to afford C3-dihydrofuran substituted coumarin in a diastereoselective manner in good yields (71–89%). 相似文献
150.
An efficient method was developed for the diastereoselective synthesis of novel fused dihydro-1H-furo[2,3-c]pyrazole by a one-pot, four-component reaction of β-keto ester, hydrazine, aromatic aldehyde, and pyridinium ylide in the presence of triethylamine under microwave irradiation in solvent-free conditions in good yields. The merits of this cascade Knoevenagel condensation/Michael addition/cyclization sequence include its high atom economy, good yields, and efficiency of producing three new bonds (two C–C and one C–O) and two stereocenters in a single operation. 相似文献