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991.
Length‐weight relationships for nine fish species of Laohegou River,a tributary of upper Yangtze River,China 下载免费PDF全文
This paper provides length‐weight relationships for nine fish species from the Laohegou River, a tributary of the upper Yangtze River. Length‐weight relationships for six of these species are recorded for the first time. New maximum lengths for two species are also reported. 相似文献
992.
Xuewu Sui Marcin Golczak Jianye Zhang Katie A. Kleinberg Johannes von Lintig Krzysztof Palczewski Philip D. Kiser 《The Journal of biological chemistry》2015,290(51):30212-30223
Carotenoid cleavage oxygenases (CCOs) are non-heme, Fe(II)-dependent enzymes that participate in biologically important metabolic pathways involving carotenoids and apocarotenoids, including retinoids, stilbenes, and related compounds. CCOs typically catalyze the cleavage of non-aromatic double bonds by dioxygen (O2) to form aldehyde or ketone products. Expressed only in vertebrates, the RPE65 sub-group of CCOs catalyzes a non-canonical reaction consisting of concerted ester cleavage and trans-cis isomerization of all-trans-retinyl esters. It remains unclear whether the former group of CCOs functions as mono- or di-oxygenases. Additionally, a potential role for O2 in catalysis by the RPE65 group of CCOs has not been evaluated to date. Here, we investigated the pattern of oxygen incorporation into apocarotenoid products of Synechocystis apocarotenoid oxygenase. Reactions performed in the presence of 18O-labeled water and 18O2 revealed an unambiguous dioxygenase pattern of O2 incorporation into the reaction products. Substitution of Ala for Thr at position 136 of apocarotenoid oxygenase, a site predicted to govern the mono- versus dioxygenase tendency of CCOs, greatly reduced enzymatic activity without altering the dioxygenase labeling pattern. Reevaluation of the oxygen-labeling pattern of the resveratrol-cleaving CCO, NOV2, previously reported to be a monooxygenase, using a purified enzyme sample revealed that it too is a dioxygenase. We also demonstrated that bovine RPE65 is not dependent on O2 for its cleavage/isomerase activity. In conjunction with prior research, the results of this study resolve key issues regarding the utilization of O2 by CCOs and indicate that dioxygenase activity is a feature common among double bond-cleaving CCOs. 相似文献
993.
994.
Alternative statistical parameter for high-throughput screening assay quality assessment 总被引:2,自引:0,他引:2
High-throughput screening is an essential process in drug discovery. The ability to identify true active compounds depends on the high quality of assays and proper analysis of data. The Z factor, presented by Zhang et al. in 1999, provides an easy and useful summary of assay quality and has been a widely accepted standard. However, as data analysis has undergone much improvement recently, the assessment of assay quality has not evolved in parallel. In this article, the authors study the implications of Z factor values under different conditions and link the Z factor with the power of discovering true active compounds. They discuss the different interpretations of Z factor depending on error distributions and advocate direct analysis of power as assay quality assessment. They also propose that in estimating assay quality parameters, adjustments in data analysis should be taken into account. Studying the power of identifying true "hits" gives a more direct interpretation of assay quality and may provide guidance in assay optimization on some occasions. 相似文献
995.
This paper provides an empirical account of commercial genetic predisposition testing in mainland China, based on interviews
with company mangers, regulators and clients, and literature research during fieldwork in mainland China from July to September
2006. This research demonstrates that the commercialization of genetic testing and the lack of adequate regulation have created
an environment in which dubious advertising practices and misleading and unprofessional medical advice are commonplace. The
consequences of these ethically problematic activities for the users of predictive tests are, as yet, unknown. The paper concludes
with a bioethical and social science perspective on the social and ethical issues raised by the dissemination and utilization
of genetic testing in mainland China. 相似文献
996.
Lanter JC Fiordeliso JJ Jiang W Allan GF Lai MT Linton O Hahn do W Lundeen SG Sui Z 《Bioorganic & medicinal chemistry letters》2007,17(1):123-126
A series of novel 2-(1H-indol-2-yl)-propan-2-ols have been designed, synthesized, and screened for their ability to inhibit testosterone-induced prostate weight increases in immature rats. Through the use of this paradigm, we were able to identify compounds that exhibited in vivo potency equal to that of the marketed antiandrogen Casodex when orally administered. 相似文献
997.
Jin C Manikumar G Kepler JA Cook CE Allan GF Kiddoe M Bhattacharjee S Linton O Lundeen SG Sui Z 《Bioorganic & medicinal chemistry letters》2007,17(21):5754-5757
A series of novel 11beta-aryl-4',5'-dihydrospiro[estra-4,9-diene-17beta,4'-oxazole] analogs have been evaluated for their antagonist hormonal properties using the T47D cell-based alkaline phosphatase assay and the A549 cell-based functional assay. Some of the compounds showed highly potent, and more selective antiprogestational activity against antiglucocorticoid activity than mifepristone (RU 486). 相似文献
998.
Jiang W Fiordeliso JJ Allan G Linton O Tannenbaum P Xu J Zhu P Gunnet J Demarest K Lundeen S Sui Z 《Bioorganic & medicinal chemistry letters》2007,17(5):1471-1474
Mifepristone is a non-selective antagonist of 3-oxosteroid receptors with both abortifacient and anti-diabetic activities. For glucocorticoid receptor (GR) program, we sought an unexplored, synthetically accessible phosphorus-containing steroidal mimetic of mifepristone, suitable for parallel synthesis of analogues. One compound 4a, with high oral bioavailability (59%) in rat, exhibited functional antagonism of GR in oral glucose tolerance test (OGTT). Thus this series of compounds might be potentially useful for the treatment of type II diabetes. 相似文献
999.
Background
There is a paucity of surrogate lung-specific biological markers that can be used to track disease progression and predict clinical outcomes in chronic obstructive pulmonary disease (COPD). The principal aim of this pilot study was to determine whether circulating surfactant protein D (SPD) or Clara Cell protein-16 (CC16) levels are associated with lung function or health status in patients with severe COPD.Methods
We studied 23 patients with advanced COPD. Lung function measurements, Chronic Respiratory Disease Questionnaire (CRQ) scores, and serum levels of SPD, CC16, and C-reactive protein (CRP) were determined at baseline and at 3 months.Results
At baseline, FEV1 was inversely associated with serum SPD levels (P = 0.045) but not with CC16 (P = 0.675) or CRP levels (P = 0.549). Over a 3 month period, changes in SPD levels correlated significantly with changes in CRQ scores (adjusted P = 0.008) such that patients who had the largest declines in serum SPD levels experienced the largest gains in health status. The association was particularly notable between circulating SPD level and the dyspnea domain of the CRQ score (P = 0.018). Changes in CC16 or CRP levels did not correlate with changes in CRQ scores.Conclusion
Changes in serum SPD levels tracked well with changes in health status over a 3 month period in patients with severe COPD. These data suggest that circulating SPD levels may be useful biomarkers to track health outcomes of COPD patients. 相似文献1000.
Guo Z Wei D Yin G Wang S Zhao S Chu Y Zhai J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,856(1-2):312-317
A HPLC method with UV detection was developed and validated for the simultaneous determination of rivanol and mifepristone in human plasma. Norethisterone was used as the internal standard. Separation was performed by a C18 reversed-phase column maintained at 20 degrees C. The mobile phase was a mixture of methanol-acetonitrile-0.05% sodium dodecylsulfonate in a 0.05 M phosphate buffer with the pH adjusted to 3.0 (30:30:40, v/v/v) at a flow rate of 0.8 ml/min. Dual wavelength mode was used, with mifepristone monitored at UV 302 nm, while rivanol and norethisterone at 272 nm. A reliable biological sample pre-treatment procedure by means of solid-phase extraction was used, which allowed to obtain good extraction efficiency (>93%) for both of the analytes and the internal standard. The calibration curves were both linear with the correlation coefficient r equal to 0.9999. For rivanol, the assay gave CV% values for precision always lower than 7.8% and mean accuracy values higher than 95.3%. As to mifepristone, precision was always lower than 10.1% and mean accuracy values were higher than 93.8%. The limit of detection for the assay of rivanol and mifepristone was 1.1 and 3 ng/ml, respectively. The method is simple, sensitive and accurate, and allow for simultaneous determination of nanogram levels of rivanol and mifepristone in human plasma. It could be applied to assess the plasma level of rivanol and mifepristone in women undergoing polypharmacy with the two drugs. 相似文献