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Sleep and Biological Rhythms - This study aims to clarify the changes in sleep-related cognitions (SRCs) of voluntary participants by a single sleep lecture (SL) using the DBAS-16 (self-recorded... 相似文献
74.
Katsuaki Kobayashi Keizo Sato Yasushi Mizuno Yoshinao Katsumata 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,677(2):275
Using capillary high-performance liquid chromatography (HPLC)-fast atom bombardment (FAB) mass spectrometry (MS), both positive and negative FAB mass spectra of 24 cephem antibiotics with diethanolamine (DEA) and glycerol (GLY) as matrices are presented. In the positive mode, an internal quasi-molecular peak together with relatively abundant fragment peaks were obtained from all 24 drugs with both matrices, though DEA provided more information on molecular mass of a compound than did GLY for some drugs. In the negative mode, the background was generally lower than that in the positive, but neither the quasi-molecular nor molecular peak was detected in several drugs with either matrix. The drugs were isolated from serum samples using an octadecyl reversed-phase cartridge; recoveries were generally over 60%. With this isolation and the capillary HPLC-FAB-MS in the positive mode, ceftriaxone and cefazolin, two of the most popular cephem antibiotics, were successfully identified in 0.5 ml of sera obtained from a clinical or an autopsy case. 相似文献
75.
Ishii A Tanaka M Kurihara R Watanabe-Suzuki K Kumazawa T Seno H Suzuki O Katsumata Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,792(1):117-121
We have presented a simple and sensitive method for determining pethidine, a narcotic analgesic drug in body fluids by gas chromatography-tandem mass spectrometry (GC-MS/MS). Pethidine and 4'-piperidinoacetophenone (internal standard) were extracted from body fluids with Bond Elut C(18) columns; the recoveries were above 85% for both compounds. The calibration curves for blood and urine showed good linearities in the range of 1.25-40 ng/ml. Its detection limits (signal-to-noise ratio=3) were estimated to be approximately 0.5 ng/ml of whole blood and urine. 相似文献
76.
Many chemicals released into the environment exhibit estrogenic activity, having the potential to disrupt development and the functioning of the endocrine system. In order to establish a model system to study the effects of such environmental chemicals on aquatic animals, we examined the effects of a natural estrogen, 17 beta-estradiol (E(2)), on early development of Fundulus heteroclitus. Embryos of F. heteroclitus were reared in seawater containing 10(-10), 10(-8), and 10(-6) M E(2) throughout the experiment. Hatching and survival rates decreased in a dose-dependent manner, and fry treated with 10(-6) M E(2) and 10(-8) M E(2) were dead by two weeks and 12 weeks after hatching, respectively. More than 85% of fry treated with 10(-8) M E(2) showed malformations: i.e., eye extrusion, crooked vertebral column, faded lateral-stripe pattern eight weeks after hatching. Body weight and head and body lengths were significantly reduced in E(2)-treated fry when compared to controls. Ossification was not completed in vertebrae, cranial bones, and other bones in fry treated with 10(-8) M E(2) even 12 weeks after hatching. Sex ratio of control fry was 57% male and 43% female, whereas fry treated with 10(-8) M E(2) were 100% female eight weeks after hatching. The present results demonstrate that exogenous estrogen induced death of embryos and fry, malformations, sex reversal, and incomplete ossification of vertebrae and cranial bones, which would result in shorter body and head lengths and in malformed vertebrae leading to a hunchback condition. 相似文献
77.
Chojnowski JL Franklin J Katsu Y Iguchi T Guillette LJ Kimball RT Braun EL 《Journal of molecular evolution》2007,65(3):259-266
Vertebrate genomes are mosaics of isochores, defined as long (>100 kb) regions with relatively homogeneous within-region base
composition. Birds and mammals have more GC-rich isochores than amphibians and fish, and the GC-rich isochores of birds and
mammals have been suggested to be an adaptation to homeothermy. If this hypothesis is correct, all poikilothermic (cold-blooded)
vertebrates, including the nonavian reptiles, are expected to lack a GC-rich isochore structure. Previous studies using various
methods to examine isochore structure in crocodilians, turtles, and squamates have led to different conclusions. We collected
more than 6000 expressed sequence tags (ESTs) from the American alligator to overcome sample size limitations suggested to
be the fundamental problem in the previous reptilian studies. The alligator ESTs were assembled and aligned with their human,
mouse, chicken, and western clawed frog orthologs, resulting in 366 alignments. Analyses of third-codon-position GC content
provided conclusive evidence that the poikilothermic alligator has GC-rich isochores, like homeothermic birds and mammals.
We placed these results in a theoretical framework able to unify available models of isochore evolution. The data collected
for this study allowed us to reject the models that explain the evolution of GC content using changes in body temperature
associated with the transition from poikilothermy to homeothermy. Falsification of these models places fundamental constraints
upon the plausible pathways for the evolution of isochores.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
Reviewing
Editor: Dr. Nicolas Galtier 相似文献
78.
Mikihiko Kawai Norie Higashiura Kimie Hayasaki Naruhei Okamoto Akiko Takami Hideki Hirakawa Kazunobu Matsushita Yoshinao Azuma 《DNA research》2015,22(5):357-366
Asaia bogorensis, a member of acetic acid bacteria (AAB), is an aerobic bacterium isolated from flowers and fruits, as well as an opportunistic pathogen that causes human peritonitis and bacteraemia. Here, we determined the complete genomic sequence of the As. bogorensis type strain NBRC 16594, and conducted comparative analyses of gene expression under different conditions of co-culture with mammalian cells and standard AAB culture. The genome of As. bogorensis contained 2,758 protein-coding genes within a circular chromosome of 3,198,265 bp. There were two complete operons encoding cytochrome bo3-type ubiquinol terminal oxidases: cyoABCD-1 and cyoABCD-2. The cyoABCD-1 operon was phylogenetically common to AAB genomes, whereas the cyoABCD-2 operon belonged to a lineage distinctive from the cyoABCD-1 operon. Interestingly, cyoABCD-1 was less expressed under co-culture conditions than under the AAB culture conditions, whereas the converse was true for cyoABCD-2. Asaia bogorensis shared pathogenesis-related genes with another pathogenic AAB, Granulibacter bethesdensis, including a gene coding pathogen-specific large bacterial adhesin and additional genes for the inhibition of oxidation and antibiotic resistance. Expression alteration of the respiratory chain and unique hypothetical genes may be key traits that enable the bacterium to survive under the co-culture conditions. 相似文献
79.
Yoshinao Katsumata Keizo Sato Masakazu Oya Osamu Suzuki Masataka Yoshino 《Life sciences》1980,27(16):1509-1512
Blood concentrations of cyanide, lactate, glucose, oxypurines and allantoin were determined in rats sampled at 10 min after the intraperitoneal administration of various concentrations of potassium cyanide. Lactate and oxypurines in plasma increased biquadratically with increase in the cyanide concentration in blood. The concentrations of cyanide for half maximal effect were 1.63 μg/ml for lactate and 2.09 μg/ml for oxypurines. Plasma glucose increased quadratically with increase in the cyanide concentration, and the marked increase was observed where plasma lactate concentration became near maximal. Plasma allantoin concentrations were not significantly changed throughout the experiments. The present results indicate that determination of plasma oxypurines as well as lactate is an excellent parameter for tissue hypoxia. 相似文献
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