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Hadar Kless Yaron Sitrit Ilan Chet Amos B. Oppenheim 《Molecular & general genetics : MGG》1989,217(2-3):471-473
Summary A λ phage DNA library ofSerratia marcescens was constructed and a clone carrying the gene coding for chitobiase (E.C.3.2.1.29) was isolated and characterized. Deletion
analysis limited the cloned region to 4.5 kb that is capable of efficient expression of chitobiase.Escherichia coli cells harboring a plasmid carrying the cloned gene express chitobiase constitutively. The molecular weight of the protein
is about 95000 daltons. In exponentially growingE. coli cells the chitobiase enzyme was found to be secreted into the periplasm. 相似文献
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Sequence of gonadal events and oestradiol levels in Sparus aurata (L.) under two photoperiod regimes
Individually tagged Sparus aurata were kept in tanks with running sea water (21°± 2°C) during their second and third years of life. Gonads were biopsied and blood was sampled at monthly intervals. Thirteen of 50 fish in the second year and 24 of 35 fish in the third year were phenotypically females. Fish kept under 16L/8D photoperiod from July 1981 to August 1982 did not reach maturation; waves of initial ovarian growth alternated with waves of atresia. When photoperiod was shortened as from August 1982, gonadal development commenced within a month and proceeded at a rate higher than that of the control fish reared under natural photoperiod. Under natural photoperiod oestradiol serum levels (E2 ) were relatively low during the resting phase, May-October (108 ± 11 pg ml−1 ), and during the late vitellogenic phase (502 ± 76 pg ml−1 ). High levels (1669 ± 312 and 1240 ± 172pg ml−1 ) occurred during the early vitellogenic and the maturational phases. The high level of E2 during the spawning season of S. aurata is explained by earlier reports indicating a prolonged breeding season with daily release of eggs, and alternating daily surges of E2 and 17α, 20β, dihydroxy-4-pregnen-3-one, possibly a 'maturational progestin' in this fish. In phenotypic males, E2 was highest during early spermatogenic phases (745 ± 142pg ml−1 ) but was low (155 ± 11 pg ml−1 ) in males with running sperm. 相似文献
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Mechanism of specificity in the Fos-Jun oncoprotein heterodimer. 总被引:23,自引:0,他引:23
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Gingold-Belfer Rachel Levy Sigal Layfer Olga Pakanaev Lea Niv Yaron Dickman Ram Perets Tsachi Tsadok 《Probiotics and antimicrobial proteins》2020,12(1):112-118
Probiotics and Antimicrobial Proteins - Lactose intolerance is a common condition caused by lactase deficiency and may result in symptoms of lactose malabsorption (bloating, flatulence, abdominal... 相似文献
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Ofir Wolach Yaron Arbel Michael Cohen Uri Goldbourt Uzi Rebhun Itzhak Shapira 《Biomarkers》2013,18(3):296-306
AbstractHigh-sensitivity C-reactive protein (hs-CRP) is a biomarker that correlates with atherothrombotic risk and outcome. hs-CRP is influenced by various modifiable and non-modifiable factors. We studied the relationship between ethnic background and hs-CRP level, among the Jewish population in Israel. A total of 3659 men and 2180 women were divided into two ethnic groups (Ashkenazi and Sephardic Jews), based on the knowledge of Jewish immigration patterns throughout the centuries. Mean hs-CRP levels were calculated for each group and were adjusted for various factors known to influence hs-CRP. Sephardic Jews were found to have higher adjusted mean hs-CRP levels (2.0 mg l?1 for men and 3.9 mg l?1 for women) compared with Ashkenazi Jews (1.5 mg l?1 for men and 2.9 mg l?1 for women). Ethnic background emerged as an independent significant predictor of hs-CRP levels. We demonstrated that ethnicity is an important factor when considering hs-CRP as a marker of atherothrombotic risk. 相似文献