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81.
Kentaro Ito Makoto Yamaguchi Teruyuki Noma Taketo Yamaji Hiroyuki Itoh Munehiro Oda 《Bioscience, biotechnology, and biochemistry》2016,80(8):1587-1593
We evaluated the effect of whey protein hydrolysates (WPH) on the water absorption rate in the small intestine using a rat small intestine perfusion model. The rate was significantly higher with 5 g/L WPH than with 5 g/L soy protein hydrolysates or physiological saline (p?0.05). WPH dose-dependently increased the water absorption rate in the range of 1.25–10.0 g/L. WPH showed a significantly higher rate than an amino acid mixture whose composition was equal to that of WPH (p?0.05). The addition of 4-aminomethylbenzoic acid, an inhibitor of PepT1, significantly suppressed WPH’s enhancement of water absorption (p?0.05). The rate of water absorption was significantly correlated with that of peptides/amino acids absorption in WPH (r?=?0.82, p?0.01). These data suggest that WPH have a high water absorption-promoting effect, to which PepT1 contributes. 相似文献
82.
MM El-Shazly El Elzayat IIA El-Sebeay YA Edmardash MM Soliman 《African Journal of Aquatic Science》2016,41(3):289-296
Manzala Lake, as one of the main Egyptian wetland ecosystems, is facing risks of pollution. An in vitro cytotoxicity test using a mammalian cell line was employed to determine the toxicity of multiple pollutants in the water and Tilapia zillii fish sampled from the lake. The concentrations of seven polychlorinated dibenzo-p-dioxins and ten polychlorinated dibenzofurans were investigated in water and muscle of the fish in 2014. Cytotoxicity testing showed that the percentage inhibition of cell viability in the studied sites ranged between 56.16% and 83.22%. Dioxin analysis indicated that the average concentrations of 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, 1,2,3,4,7,8-hexachlorodibenzofuran, 1,2,3,4,6,7,8-heptachlorodibenzofuran and 1,2,3,4,6,7,8,9-octachlorodibenzofuran were higher than the toxic equivalence quotients (TEQs) set by the World Health Organization (WHO) in all water and fish muscle samples; however, the average concentration of 2,3,7,8-tetrachlorodibenzofuran was higher only in fish muscle samples. The bioaccumulation factor (BAF) ranged dramatically between 2 and 58.5 for the detected dioxins. Adverse human health effects through the consumption of fish are not expected, because dioxin levels in fish muscle are deemed safe for human consumption. Implementation of a strategic multidisciplinary action plan is strongly recommended to sustain this delta wetland ecosystem. 相似文献
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86.
A Taketo 《Molecular & general genetics : MGG》1981,183(1):130-133
Summary The effect of the dnaN mutation on the growth of single-stranded DNA phages was studied by burst experiments. In HC138 dnaN cells exposed to 42.5° C at 5 min before infection, growth of spherical (microvirid or isometric) phages such as 3, Kh-1 and X174 was partially reduced at the nonpermissive temperature. When infection was performed at 30 min after temperature shift-up, viral replication was completely inhibited at 42.5° C in the dnaN strain but not in a dna
+ revertant. At 41° C, multiplication of filamentous (inovirid) phages M13 and fd was restricted specifically in HC138 F+
dnaN bacteria. When dnaN cells lysogenic for i21 were grown at 42.5° C for 60 min and then shifted down to 33° C, a burst of i21 occurred with concomitant cellular lysis, manifesting induction of the prophage development. 相似文献
87.
88.
Sans résuméI. Analyse électrocapillaire des matières colorantes. Rev. gén. Mat. Col. 1926 Vol. 30 pp 34–45II. Phénomènes électrocapillaires et le problème du cancer. Arch. Med. Exper. 1926 Vol. I p 381III. Phénomènes électrocapillaires et l'antagonismes microbiens. Bol. Istituto Sier. Milano 1927 Vol. VI p 313. 相似文献
89.
In the companion paper (Holmquist et al. 1988), we concluded that there is
no agreement on either the correct branching order or differential rates of
evolution among the higher primates, and we examined in depth why this
uncertainty in the evolutionary understanding of our closest living
relatives persists. Recently, Lake developed two novel methods, based on
group properties of transition and transversion operators, that (a) permit,
in principle, objective resolution of problems of the above type and (b)
attach a statistical significance level to the conclusions drawn. In the
present paper, we develop formulas for using these two methods in tandem
and apply them to study transversion differences in (1) nuclear DNA for a
7-kb segment of the psi eta-globin locus and a 3-kb intergenic region
between the psi beta- and delta- globin loci and (2) mitochondrial DNA for
the 896-bp fragment of Brown et al. Although each of these nucleotide
sequence regions has its characteristic tempo and mode of evolution, the
nuclear and mitochondrial data together, comprising a total of 10,939 base
positions, support a Homo/Pan clade at the 97% confidence level. If we
calibrate the divergence point for humans and chimpanzees at 5 Myr,
consideration of the transversion branch lengths for the combined nuclear
data indicates that the gorilla lineage branched off 600,000- 900,000 years
prior to that, although the 2 sigma sampling errors do not preclude either
a temporal trifurcation for the three species or a considerably more
ancient branch point for the gorilla. To resolve the length of this central
branch to a relative accuracy of 25% and 30% will require a factor of 16
and nine times more data, respectively-- i.e., in excess of 100,000
homologous nucleotides for each of the four primates. For the nuclear
genes, heterogeneity in evolutionary rates between different parts of the
genome is mostly restricted to the human lineage for these two segments.
The lineage leading to chimpanzees has evolved 0.4 (3-kb fragment) to 3.5
(7-kb segment) times as rapidly as the lineage leading to humans, and that
leading to the gorilla has evolved approximately one-fifth to one-half as
rapidly as that leading to chimpanzees. Thus, even local molecular clocks
can "tick" badly. As significant is the fact that virtually contiguous
parts of the genome tick at markedly different rates.(ABSTRACT TRUNCATED AT
400 WORDS)
相似文献
90.
It has been found that when the Y chromosome from Mus musculus domesticus (YDOM) is placed onto the C57BL/6J (B6) mouse background, the XY progeny (B6.YDOM) develop ovaries or ovotestes but not normal testes during fetal life. We examined the ontogeny of the abnormal testicular differentiation in the B6.YDOM ovotestis by immunocytochemical staining for Müllerian inhibiting substance (MIS). We found that the B6.YDOM ovotestis initiated testicular differentiation later in development than did the control B6 testis. When the YDOM was transferred onto the SJL J mouse background by crossing B6.YDOM males with SJL/J females, all XY progeny developed normal testes. The onset of testicular differentiation was at the same developmental stage as in the B6 male fetus. These results suggest that the delay of testicular differentiation is not due to the effect of the YDOM chromosome itself, but due to improper interaction of the testis-determining gene on the YDOM chromosome with autosomal genes of B6. In addition, we found a close correlation between the arrest of germ cells at the prespermatogonia stage and MIS production of adjacent somatic cells in the B6.YDOM ovotestis. This result may support the hypothesis that MIS is involved in the regulation of germ cell differentiation. 相似文献