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991.
The objective of the study was to investigate whether the lysosomal enzyme, N-Acetyl-beta-D-glucosaminidase (NAG) activity is increased in plasma of patients with acute myocardial infarction (AMI) and to determine if there is any association between plasma levels of NAG and severity of myocardial infarction (MI). NAG activity in plasma was monitored in 69 patients with AMI and 135 normal healthy subjects using a spectrofluorimetric method. A modified Aldrich ST elevation score was used to gauge the severity of MI in terms of size of the infarct. Plasma NAG levels in AMI patients and normal healthy subjects were found to be 10.92+/-7.5 U/l and 6.8+/-2.2 U/l, respectively. These two mean value when compared by Student's t-test were significantly different P = 0.0001. No statistically significant differences in NAG activity were observed in patients in terms of gender, age, location of infarct, time from onset of chest pain to blood sampling in the hospital and size of the infarct. 相似文献
992.
Syed Mahmud Hasan 《Journal of polymer science. Part A, Polymer chemistry》1982,20(10):2969-2978
A study of the effects of ingredients on styrene emulsion polymerization kinetics showed that the purity of sodium dodecyl sulfate emulsifier affected the rate of polymerization (Rp) in the absence of added initiator. Below a critical concentration oxygen accelerated the Rp; above the critical concentration it inhibited the Rp. The effect of distilling styrene, compared to washing it with alkali to deinhibit, was minimal. Indications are that particulate dispersions of silica and titanium dioxide are encapsulated in situ by the growing polymer chains during styrene emulsion polymerization. 相似文献
993.
4‐Ethoxycarbonyl‐5‐phenyl‐2,3‐dihydrofuran‐2,3‐dione 1 reacts with aldehydes via the acylketene intermediate 2 giving the 1,3‐dioxin‐4‐ones 3a‐e and the 1,4‐bis(5‐ethoxycarbonyl‐4‐oxo‐6‐phenyl‐4H‐1,3‐dioxin‐2‐yl)benzene 4 , and a one step reaction between dibenzoylmethane and oxalylchloride gave 3,5‐dibenzoyl‐2,6‐diphenyl‐4‐pyrone 7 . The reaction of 1 with dibenzoylmethane, a dicarbonyl compound, provided ethyl 3‐benzoyl‐4‐oxo‐2,6‐diphenylpyran‐5‐carboxylate derivative 9 . Compound 9 was converted into the corresponding ethyl 3‐benzoyl‐4‐hydroxy‐2,6‐diphenylpyridine‐5‐carboxylate derivative 10 via its reaction with ammonium hydroxyde solution in 1 ‐butanol. 相似文献
994.
Photophysical Properties of Tin Ethyl Etiopurpurin I (SnET2) and Tin Octaethylbenzochlorin (SnOEBC) in Solution and Bound to Albumin 总被引:2,自引:0,他引:2
Brian W. Pogue Robert W. Redmond Niraj Trivedi Tayyaba Hasan 《Photochemistry and photobiology》1998,68(6):809-815
Abstract— The photophysical characteristics of two second-generation PDT photosensitizers, tin ethyl etiopurpurin I (SnET2 ) and tin octaethylbenzochlorin (SnOEBC), have been measured in homogeneous solution and when bound to bovine serum albumin (BSA). The ground state and triplet state absorption spectra have been characterized, as have triplet lifetimes and quantum yields for intersys-tem crossing, singlet oxygen formation and photobleaching. In total, these parameters provide a complete set of data that can be used to quantitatively compare the photosensitizing efficiencies of these molecules. The photo-bleaching quantum yield of SnET2 is increased dramatically when it is bound to BSA, thus limiting the production of singlet oxygen at incident fluences above 1 J/cm2 . In contrast, the quantum yield of photobleaching of SnOEBC is at least an order of magnitude lower than that of SnET2 under these conditions and does not significantly limit the photosensitization process for typical in vivo or in vitro fluences. This difference is expected to play a significant role in determining the relative photosensitizing ability of these compounds in vivo. 相似文献
995.
A new iridoid glycoside, sintenoside ( 1 ) and two new phenylethyl glycosides, globusintenoside (=2‐(3,4‐dihydroxyphenyl)ethyl‐O‐6‐O‐feruloyl‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl‐(1→3)‐4‐O‐caffeoyl‐β‐D ‐glucopyranoside; 2 ) and 3′′′‐O‐methylcrenatoside (=1,2‐O‐[2‐(3,4‐dihydroxyphenyl)ethan‐1,2‐diyl]‐3‐O‐α‐L ‐4‐O‐feruloyl‐rhamnopyranosyl‐β‐D ‐glucopyranose; 3 ) were isolated from the underground parts of Globularia sintenisii, along with three known iridoid glycosides, lytanthosalin, globularin, catalpol, and six known phenylethyl glycosides, verbascoside, isoverbascoside, leucoscepthoside A, plantainoside C, martynoside, and isocrenatoside. The structure elucidation of the isolated compounds was performed by spectroscopic methods (MS and 1D and 2D NMR). 相似文献
996.
997.
998.
Amiri Delouei Amin Emamian Amin Karimnejad Sajjad Sajjadi Hasan Jing Dengwei 《Journal of Thermal Analysis and Calorimetry》2021,144(3):611-621
Journal of Thermal Analysis and Calorimetry - This study aimed at presenting a steady-state analytical solution for the two-dimensional heat conduction in a cylindrical segment made of functionally... 相似文献
999.
Aziz Farina Al Noman Md Abdullah Hasan Choudhury Mahmood Ahsan Monira 《Chemistry of Natural Compounds》2022,58(3):450-454
Chemistry of Natural Compounds - A new iridoid aglycone, 1-acetylscyphiphin B2, along with two known iridoid aglycones and three triterpenes, was isolated from the whole plant of Lindenbergia... 相似文献
1000.
Sumon Ganguli Md. Akter Hosen Rifat Sabbir Howlader Md. Abid Hasan Shahidul Islam Md.Nur E. Alam Md. Nazrul Islam 《印度化学会志》2022,99(8):100585
This study aimed at evaluating the water quality of Bhatiari Lake (BL) for the first time based on water quality parameters, pollution indices, hydrochemical signatures and hydro-statistical analysis. Lake water samples were collected from the lake during April–May 2019 and wide ranges of parameters were considered for the investigation. Except for COD and Fe, all the parameters were within the permissible limit. COD crossed Bangladesh standards and testing institution (BSTI) and United States environmental protection agency (USEPA) standards. In contrast, Fe crossed World health organization (WHO), Bureau of Indian Standards (BIS) and USEPA standards. Hydrochemical analysis indicated the water as soft-fresh where near neutral low-metal was noticed from the Ficklin-Caboi diagram. Ca2+-Mg2+-HCO3- type water was confirmed from Piper and Chadha diagram, whereas Durov and Schoeller's diagram were indicated the influence of Mg2+-HCO3-. The trend of cations and anions were Ca2+> Mg2+> Na+>K+ and HCO3? > Cl? > NO3? > SO42? > PO43? as stated by pie chart. Most precipitation dominant water was confirmed from the Gibbs diagram. Principal component analysis (PCA), Cluster analysis (CA) and Correlation matrix (CM) indicated the co-existence of geogenic and anthropogenic sources for pollution. Good water quality was observed via an integrated approach namely degree of contamination (Cd), Single-Factor Pollution Index (SPI), Comprehensive pollution index (CPI), Heavy metal evaluation index (HEI), Heavy metal pollution index (HPI), Nemerow's pollution index (NPI) and Ecological risk index (ERI). In addition, water quality index (WQI) remarked the water is excellent. Taken collectively, the present study indicates the BL water can be considered pollution-free. 相似文献