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121.
Urinary excretion of hydroxycinnamates and flavonoids after oral and intravenous administration. 总被引:5,自引:0,他引:5
The urinary recoveries of the hydroxycinnamates, ferulic acid (3-methoxy, 4-hydroxy cinnamic acid), and chlorogenic acid (the quinic acid ester of 3,4-dihydroxycinnamic acid), and three structurally related flavonoids were studied in the rat. For the latter, the aglycone quercetin was compared with its 3-glucoside (isoquercitrin) and 3-rhamnoglucoside (rutin). Doses of 50 mg/kg were administered via the oral and intravenous routes and urine collected over the subsequent 24-h period. Reverse phase HPLC with photo-diode array detection was used to analyze the unchanged compound and their metabolites excreted in the urine. Ferulic acid and isoquercitrin were orally absorbed (5.4 and 0.48% of administered dose, respectively) and are therefore bioavailable. In contrast, neither unchanged chlorogenic acid, rutin, quercetin, nor the conjugated metabolites in the form of glucuronide or sulphate were detected in the urine after oral dosing. All the flavonoids studied produced low total urinary recoveries after intravenous administration, 9.2% for quercetin-3-rhamnoglucoside, 6.7% for the 3-glucoside, and 2.4% for the aglycone, indicating that extensive metabolism to low molecular weight compounds or excretion via other routes may be occurring. Overall it can be stated that renal excretion is not a major pathway of elimination for intact flavonoids and hydroxycinnamates in the rat. 相似文献
122.
Prediction of Anti‐Alzheimer's Activity of Flavonoids Targeting Acetylcholinesterase in silico
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123.
Length‐weight relationships of Badis dibruensis Geetakumari and Vishwanath, 2010 (Badidae) and Lepidocephalichthys arunachalensis (Datta and Barman, 1984) (Cobitidae) from Subansiri River (Brahmaputra basin), Northeast India
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H. Choudhury S. Mili S. Basumatary A. Mazumder D. Sarma 《Zeitschrift fur angewandte Ichthyologie》2017,33(6):1294-1295
Length–weight relationships (LWRs) for Badis dibruensis and Lepidocephalichthys arunachalensis, collected from the lower Subansiri River (Brahmaputra basin) in Assam, India from March 2016 to April 2017 using fishing gears namely cast nets (2.5 m, 1 m; 10–15 mm mesh size) and gillnets (30 × 0.9 m; 5–10 mm mesh size), are presented based on seasonal collections. The b values in the LWRs were determined as 2.56 for B. dibruensis and 3.28 for L. arunachalensis. 相似文献
124.
Length–weight relationships of Barilius bendelisis (Hamilton, 1807), Barilius shacra (Hamilton, 1822) and Barilius barna (Hamilton, 1822) from Manas River in Assam,India
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The present study describes the length–weight relationships (LWRs) for three ornamental hill stream fish species from the Manas River in Assam, India, namely, Barilius bendelisis (Hamilton, 1807), Barilius shacra (Hamilton, 1822), and Barilius barna (Hamilton, 1822). Fishes were collected on a monthly basis from March 2015 to February 2016 with cast nets (270 cm, 1.2 cm) and gillnets (7,500 × 130 cm, 5 cm). This is the first information on LWR data for two of the species. 相似文献
125.
Zhengyuan Tu Michael J. Zachman Snehashis Choudhury Shuya Wei Lin Ma Yuan Yang Lena F. Kourkoutis Lynden A. Archer 《Liver Transplantation》2017,7(8)
Successful strategies for stabilizing electrodeposition of reactive metals, including lithium, sodium, and aluminum are a requirement for safe, high‐energy electrochemical storage technologies that utilize these metals as anodes. Unstable deposition produces high‐surface area dendritic structures at the anode/electrolyte interface, which causes premature cell failure by complex physical and chemical processes that have presented formidable barriers to progress. Here, it is reported that hybrid electrolytes created by infusing conventional liquid electrolytes into nanoporous membranes provide exceptional ability to stabilize Li. Electrochemical cells based on γ‐Al2O3 ceramics with pore diameters below a cut‐off value above 200 nm exhibit long‐term stability even at a current density of 3 mA cm?2. The effect is not limited to ceramics; similar large enhancements in stability are observed for polypropylene membranes with less monodisperse pores below 450 nm. These findings are critically assessed using theories for ion rectification and electrodeposition reactions in porous solids and show that the source of stable electrodeposition in nanoporous electrolytes is fundamental. 相似文献
126.
127.
R. K. Choudhury 《International Journal of Anthropology》2005,20(1-2):27-38
The paper reports finger dermatoglyphics of three groups of Kondhs namely Kutia, Dongoria and Kuvi, tribes of Orissa, India.
The analysis of bilateral finger prints of 663 unrelated males and females includes both qualitative and quantitative characters.
Marked bisexual and inter-group differences for several characters have been observed. But bimanual differences have not been
observed in finger patterns. All the three groups are characterized by a high frequency of loops. The whorl-loop ratio indicates
the low incidence of whorls particularly among the Kuvi males and females and that of inter-group difference have been observed
between Dongoria females and Kuvi females. The three groups show very close affinity in the present study. The three groups
of Kondhs show similar trend when compared with the available data in India and show very close affinity. 相似文献
128.
Choudhury K Zander D Kube M Reinhardt R Clos J 《International journal for parasitology》2008,38(12):1411-1423
Resistance to treatment is a growing problem in efforts to control Old World leishmaniasis. Parasites resistant to new therapeutics such as miltefosine have not been reported from the field yet but based on experimental evidence, may appear soon. Therefore, we attempted to identify genetic markers that may correlate with miltefosine resistance. Using a functional cloning approach, we have isolated a gene from Leishmania infantum that, upon over-expression, confers protection not only against miltefosine, but also against Sb(III), the active principle of anti-leishmanial antimonials. The gene encodes a very large putative polypeptide of 299 kDa that shows no similarities to known proteins or functional motifs. Database mining and karyotyping experiments suggest that in L. infantum this gene is part of a 44-kbp duplicated region that is found on two separate chromosomes, CHR08 and CHR29. 相似文献
129.
An aprotinin sensitive serine protease was identified in the culture supernatant of the Indian strain of Leishmania donovani (MHOM/IN/1983/AG83). The protease was subsequently purified and characterized. The apparent molecular mass of the enzyme was 115 kDa in SDS-PAGE under non-reducing condition, while on reduction it showed a 56 kDa protein band indicating that the protease is a dimeric protein. The purified enzyme was optimally active at the pH and temperature of 7.5 and 28 degrees C, respectively. Assays of thermal stability indicated that the enzyme preserved 59% of activity even after pretreatment at 42 degrees C for 1 h. The purified protease was not glycosylated and its isoelectric pI was 5.0. N-alpha-p-tosyl-L-arginine methylester (TAME) appeared to be relatively better substrate among the commonly used synthetic substrates. The enzyme was inhibited by Ca(2+) and Mn(2+), but activated by Zn(2+). The protease could play important role(s) in the pathogenesis of visceral leishmaniasis or kala-azar. 相似文献
130.
Mozaffari F Lindemalm C Choudhury A Granstam-Björneklett H Lekander M Nilsson B Ojutkangas ML Osterborg A Bergkvist L Mellstedt H 《Cancer immunology, immunotherapy : CII》2009,58(1):111-120
Immunotherapy is being increasingly utilized for adjuvant treatment for breast cancer (BC). We have previously described immune
functions during primary therapy for BC. The present study describes immune recovery patterns during long-term, unmaintained
follow-up after completion of adjuvant therapy.A group of patients with primary BC had been treated with adjuvant radio-chemotherapy
(RT + CT) 5-fluorouracil, epirubicin and cyclophosphamide (FEC) (n = 21) and another group with radiotherapy (RT) (n = 20) alone. Immunological testing of NK and T-cell functions was performed initially at the end of adjuvant treatment and
repeated after 2, 6 and 12 months. NK cell cytotoxicity was significantly higher (P < 0.05) at all time-points in patients than in age-matched controls and did not differ between the two treatments groups
during one year observation. In contrast, lower numbers of CD4 T-cells and lower expression of CD28 on T-cells was observed
particularly in RT + CT patients and did not normalize during the observation period. The numbers of Treg cells (CD4+CD25high) were low in the RT + CT group during follow-up, as well as expression of TCRξ, Zap70, p56lck, P59fyn and PI3 k in CD4+ cells. In contrast, expression of intracellular cytokines (IFN-γ, IL-2, IL-4) in CD4 and CD8 T cells were significantly higher
in RT + CT patients than in the RT group and the difference increased during follow-up. In conclusion, NK-cell cytotoxicity
increased during unmaintained long-term follow-up whereas CD4 and regulatory T cells as well as signal transduction molecules
remained low following adjuvant radio-chemotherapy. 相似文献