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排序方式: 共有229条查询结果,搜索用时 31 毫秒
161.
Ashok Aspatwar Harlan Barker Heidi Aisala Ksenia Zueva Marianne Kuuslahti Martti Tolvanen Craig R. Primmer Jaakko Lumme Alessandro Bonardi Amit Tripathi Seppo Parkkila Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1577
A β-class carbonic anhydrase (CA, EC 4.2.1.1) was cloned from the genome of the Monogenean platyhelminth Gyrodactylus salaris, a parasite of Atlantic salmon. The new enzyme, GsaCAβ has a significant catalytic activity for the physiological reaction, CO2 + H2O ⇋ HCO3− + H+ with a kcat of 1.1 × 105 s−1 and a kcat/Km of 7.58 × 106 M−1 × s−1. This activity was inhibited by acetazolamide (KI of 0.46 µM), a sulphonamide in clinical use, as well as by selected inorganic anions and small molecules. Most tested anions inhibited GsaCAβ at millimolar concentrations, but sulfamide (KI of 81 µM), N,N-diethyldithiocarbamate (KI of 67 µM) and sulphamic acid (KI of 6.2 µM) showed a rather efficient inhibitory action. There are currently very few non-toxic agents effective in combating this parasite. GsaCAβ is subsequently proposed as a new drug target for which effective inhibitors can be designed. 相似文献
162.
Mikko Tiainen Kaisa Tiippana Martti Vainio Tarja Peromaa Naeem Komeilipoor Lari Vainio 《PloS one》2016,11(3)
Recent studies have shown that articulatory gestures are systematically associated with specific manual grip actions. Here we show that executing such actions can influence performance on a speech-categorization task. Participants watched and/or listened to speech stimuli while executing either a power or a precision grip. Grip performance influenced the syllable categorization by increasing the proportion of responses of the syllable congruent with the executed grip (power grip—[ke] and precision grip—[te]). Two follow-up experiments indicated that the effect was based on action-induced bias in selecting the syllable. 相似文献
163.
Magdalena Ydreborg Vera Lisovskaja Martin Lagging Peer Brehm Christensen Nina Langeland Mads Rauning Buhl Court Pedersen Kristine M?rch Rune Wejst?l Gunnar Norkrans Magnus Lindh Martti F?rkkil? Johan Westin 《PloS one》2014,9(4)
Diagnosis of liver cirrhosis is essential in the management of chronic hepatitis C virus (HCV) infection. Liver biopsy is invasive and thus entails a risk of complications as well as a potential risk of sampling error. Therefore, non-invasive diagnostic tools are preferential. The aim of the present study was to create a model for accurate prediction of liver cirrhosis based on patient characteristics and biomarkers of liver fibrosis, including a panel of non-cholesterol sterols reflecting cholesterol synthesis and absorption and secretion. We evaluated variables with potential predictive significance for liver fibrosis in 278 patients originally included in a multicenter phase III treatment trial for chronic HCV infection. A stepwise multivariate logistic model selection was performed with liver cirrhosis, defined as Ishak fibrosis stage 5–6, as the outcome variable. A new index, referred to as Nordic Liver Index (NoLI) in the paper, was based on the model: Log-odds (predicting cirrhosis) = −12.17+ (age×0.11) + (BMI (kg/m2)×0.23) + (D7-lathosterol (μg/100 mg cholesterol)×(−0.013)) + (Platelet count (x109/L)×(−0.018)) + (Prothrombin-INR×3.69). The area under the ROC curve (AUROC) for prediction of cirrhosis was 0.91 (95% CI 0.86–0.96). The index was validated in a separate cohort of 83 patients and the AUROC for this cohort was similar (0.90; 95% CI: 0.82–0.98). In conclusion, the new index may complement other methods in diagnosing cirrhosis in patients with chronic HCV infection. 相似文献
164.
165.
Martti Vaara 《FEMS microbiology letters》1992,97(3):249-254
Only a few prokaryotic or eukaryotic enzymes are known to consist of a tandem-repeat structure. This report describes a common hexapeptide-repeat theme in four Escherichia coli transferases and in four less-characterized bacterial proteins. The proteins are the Ssc protein of Salmonella typhimurium (25), UDP-N-acetylglucosamine acyltransferase of E. coli (24), the hypothetical proteins Tms of Bacillus subtilis (23) and Yglm of E. coli (22), succinyldiaminopimelate aminotransferase of E. coli (14), serine acetyltransferase of E. coli (13), NodL of Rhizobium leguminasorum (13), and thiogalactoside acetyltransferase of E. coli (8) (number of repeats indicated in parentheses). In UDP-N-acetylglucosamine acyltransferase, the repeats constitute 55% of the total protein. Each hexapeptide repeat of the eight proteins starts with Ile, Leu, or Val. Position b is occupied by Gly, position d by Gly, Asn, or Asp, and position e by Val or Ala in 52%, 54%, and 56% of the hexapeptide repeats, respectively. 相似文献
166.
167.
An automatic gas counter for quantitative micro-determinations of tritium in biological material 总被引:1,自引:0,他引:1
An automatic microcounter for quantitative determinations of tritium has been developed. It has a background of 0.5 cpm and a constant and quench-free efficiency of 57.4 ± 2.1% ( 6600). Radioactivities of 2 pCi can be measured with a standard deviation of ±10% using a 1-hr counting time. It is particularly adapted for tritium microassay from biological material in which tritium is converted to a gaseous state by a single step combustion and reduction method, utilizing a mixture of metallic zinc and anhydrous sodium carbonate. Samples weighing up to 2 mg can be measured using sample ampules made of Pyrex glass with outer diameter of 5 mm and length of 30 mm. The material costs are extremely low and one technician can load and scal over 100 samples in a day. The apparatus may have significance as an additional instrument beside liquid scintillation counters in the region of radioactivities below 20 pCi. The method has been successfully used in investigations concerning steroid metabolism in rat adrenal cortex and testis. Specific activities have been determined from tissue samples weighing 1 μg and less. 相似文献
168.
169.
A 19-gauge needle biopsy was taken of the testis of mink in late January. When scores from 1 to 10 were given according to the developmental stage and number of spermatogenic cells, males scoring 8-10 returned significantly better breeding results than did males having scores less than 7. The biopsy did not affect libido or induce other disturbances of fertility. Fine-needle aspiration biopsy of the testis is possibly the most convenient and accurate infertility assay in mink breeding. 相似文献
170.
Scoring the agar plate before incubation under unidirectional light led to a rapid separation of gliding filamentous cyanobacteria from their contaminating bacteria. Twenty strains were purified by the method. Additionally, 13 axenic cyanobacterial strains were isolated from pour plates made after treatment of cyanobacterial cultures in tryptone-yeast extract-glucose broth with cycloserine in darkness to select for obligate photoautotrophs. 相似文献