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131.
The evolution of photochemotherapy with psoralens and UVA (PUVA): 2000 BC to 1992 AD. 总被引:1,自引:0,他引:1
M A Pathak T B Fitzpatrick 《Journal of photochemistry and photobiology. B, Biology》1992,14(1-2):3-22
The therapeutic uses of naturally occurring psoralens in modern-day medicine (8-methoxypsoralen (8-MOP), 5-methoxypsoralen (5-MOP), 4,5',8-trimethylpsoralen, and a few other synthetic psoralens) have evolved through five stages of development. (1) In the historical period (2000 BC to 1930 AD), the pigment-stimulating properties of naturally occurring plants containing psoralens were described anecdotally. (2) The second period (1930-1960) dealing with the chemistry of psoralens involved extraction, identification of their structure, synthesis, and the relationship between chemical structure and their photoreactivity and pigment-stimulating properties. The treatment of vitiligo with oral and topical 8-MOP became popular. (3) In the third period (1960-1974), we witnessed a new beginning and the growth of basic science studies and clinical investigations into various biological properties of psoralens including action spectrum studies, mutagenesis and carcinogenesis studies, in vitro and in vivo photoreactivity studies of various psoralens with DNA, RNA, proteins, and pharmacological and toxicological studies in vitiligo patients undergoing long-term therapy for repigmentation. (4) The fourth period (1974-1988) is recognized as the period of photochemotherapy and the development of the science of photomedicine which established the therapeutic effectiveness of psoralens in combination with newly developed UV irradiation systems that emitted high-intensity UVA radiation in the treatment of severe psoriasis, mycosis fungoides, and over 16 other skin diseases. The effectiveness of PUVA (psoralen + UVA) was confirmed by well controlled clinical trials in thousands of patients, both in the USA and in European countries. Combination therapy with oral retinoids and PUVA contributed to greater effectiveness and long-term safety of psoralen photochemotherapy. (5) In the fifth period (1989 and beyond), psoralens are now emerging as photochemoprotective agents against non-melanoma skin cancers and as immunologic modifiers in the management of certain patients with disorders of circulating T-cells using new techniques of photopheresis. In the final analysis, perhaps the application of pharmacological and therapeutic concepts and principles of using psoralens in combination with UVA has contributed to the development of a new science of photomedicine in which the interaction between basic scientists, photobiologists, and physicians has produced both basic and new clinical knowledge for the care and control of human suffering. 相似文献
132.
The excess volumes of four isomeric butanols with di-n-butyl ether were determined at 30°C. The isomeric effect was distinctly observed in the excess volume profiles. 1-Butanol
and 2-methyl-l-propanol systems exhibited negative excess volumes throughout the concentration range. The 2-butanol system
had positive excess volumes up to 0.9 mol fraction of alcohol after which it became negative, while the 2-methyl-2-propanol
system exhibited positive excess volumes throughout the concentration range.
NCL Communication No. 4678 相似文献
133.
Ajita Pathak Ruchi Agarwal Vishwambhar Dayal Gupta 《Journal of Macromolecular Science: Physics》2013,52(2):245-260
Vibrational dynamics of the α‐polymorphic form of trans‐1‐4‐polyisoprene is described using Higg's method and the Urey‐Bradley force field. Characteristic features of dispersion profiles such as repulsion and bunching are reported. A comparison with the β‐form is presented and possible reasons for variation in heat capacity are discussed. 相似文献
134.
Highly efficient Pd‐PEPPSI‐IPr catalyst for N‐(4‐pyridazinyl)‐bridged bicyclic sulfonamides via Suzuki–Miyaura coupling reaction
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Mallikarjuna Reddy Sura N. Reddy Bijivemula Sreekanth Reddy Pogula Venkata Krishna Reddy Motakatla Pathak Madhvesh Vasu Govardhana Reddy Peddiahgari 《应用有机金属化学》2018,32(2)
A protocol for the Suzuki–Miyaura coupling of novel 2‐(6‐chloropyridazin‐3‐yl)‐5‐(aryl/heteroarylsulfonyl)‐2,5‐diazabicyclo[2.2.1]heptanes and heteroarylboronic acids to afford variety of coupled products was realized. Pd‐PEPPSI‐IPr catalyst was found to be a powerful and reusable catalyst under relatively mild reaction conditions. 相似文献
135.
The glucopyranosyl moiety (ring I) of paromomycin was modified in a search for novel aminoglycoside antibiotics. The key intermediates were the 4′,6′‐O‐benzylidenated N‐Boc derivative 3 and the azido analogue 18 . The bromobenzoates 4 and 19 were prepared by treating the benzylidene acetals 3 and 18 , respectively, with N‐bromosuccinimide (NBS), and the diol 8 was obtained by hydrogenolysis of 3. The C(6′)‐deoxy derivative 5 was obtained from 4 by treatment with Bu3SnH. Selective fluorodehydroxylation of 8 gave the fluoro derivative 9. The pseudotrisaccharide 13 was obtained by reductive fragmentaion of the iodo compound 12 obtained from the bromobenzoate 4 . The 3′,6′‐anhydro derivative 20 was obtained upon deacetylation of 19. Standard deprotection gave the C(6′)‐deoxy compound 7 , the fluoro compound 11 , the pseudotrisaccharide 15 , and the 3′,6′‐anhydro‐paromomycin 22 . As compared to paromomycin, the C(6′)‐deoxy and fluorodeoxy derivatives 7 and 11 showed a lower activity against both wild type 1408A and 1408G mutant ribosomes. A lower activity was also found for the 3′,6′‐anhydro derivative 22 and for the pseudotrisaccharide 15 . 相似文献
136.
G. Pathak R. Katiyar K. Agrahari A. Srivastava R. Dabrowski K. Garbat R. Manohar 《Opto-Electronics Review》2018,26(1):11-18
In the present work TiO2 nanoparticles (NPs) have been dispersed into three different nematic liquid crystals (2020, 1823A and 1550C) in different concentration. The value of the birefringence (Δn) has been calculated by the transmitted intensity method at a 632.8 nm wavelength. NLC 2020 used in the present study is a high birefringent material (Δn = 0.44), NLC 1550C is a low birefringent material (Δn = 0.067) and NLC 1823A is a mid birefringent material (Δn = 0.14). An increased value of birefringence has been found after dispersion of TiO2 NPs in all three NLCs but this increment depends upon the concentration of the dopant material, temperature range and chemical character of the mixtures. It is suggested that this LC materials can be applicable in making of phase shifters, compensators and many more photonic devices. 相似文献
137.
138.
S Pathak S K Choi N Arnheim M E Thompson 《Journal of the American Chemical Society》2001,123(17):4103-4104
139.
140.
Experimental Techniques for Finite Shear Strain Measurement within Two Advanced High Strength Steels
Experimental Mechanics - There is a growing need to experimentally characterize local shear deformation in advanced high strength steels (AHSS) for the calibration of stress-state dependent... 相似文献