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排序方式: 共有681条查询结果,搜索用时 281 毫秒
671.
672.
Ichthyological Research - Larvae and juveniles of three species in the family Gobiidae were described based on reared material; Priolepis borea survived to post-settlement, and Priolepis cincta and... 相似文献
673.
Cells of Escherichia coli mounted on a hydrophobic filter membrane were dried under various vapor pressures. A mutant defective in deoxyribonucleic acid repair (uvrA recA) was more sensitive to drying at a water activity of 0.53 or below than the parent strain but not at a water activity of 0.75 and above. Sucrose gradient studies showed that single- and double-strand breaks of deoxyribonucleic acid occurred at a water activity of 0.53 or below, but no breaks could be observed at a water activity of 0.75 or above. These results were observed in all cells rehydrated with 0.03 M tris (hydroxymethyl) aminomethane-hydrocholoride buffer solution at 0 or 37 degrees C, in the presence or absence of oxygen, with saturated water vapor or with a hypertonic solution followed by a gradual dilution. Freezable water was detected in the cells only at a water activity above 0.75 by differential scanning calorimetry. Removal of unfreezable water of cells in the drying, therfore, might induce deoxyribonucleic acid strand breaks. 相似文献
674.
675.
A representative haploid R-banded karyotype of the domestic pig, and a diagrammatic representation of the banding patterns at the 550 band level are presented. 相似文献
676.
Takahiro Ide Shota Mochiji Noriko Ueki Katsushi Yamaguchi Shuji Shigenobu Masafumi Hirono Ken-ichi Wakabayashi 《Biochemistry and Biophysics Reports》2016
The unicellular green alga Chlamydomonas reinhardtii is a model organism for various studies in biology. CC-124 is a laboratory strain widely used as a wild type. However, this strain is known to carry agg1 mutation, which causes cells to swim away from the light source (negative phototaxis), in contrast to the cells of other wild-type strains, which swim toward the light source (positive phototaxis). Here we identified the causative gene of agg1 (AGG1) using AFLP-based gene mapping and whole genome next-generation sequencing. This gene encodes a 36-kDa protein containing a Fibronectin type III domain and a CHORD-Sgt1 (CS) domain. The gene product is localized to the cell body and not to flagella or basal body. 相似文献
677.
Floyd E. Bloom Elena L.F. Battenberg Tamotsu Shibasaki Robert Benoit Nicholas Ling Roger Guillemin 《Regulatory peptides》1980,1(3):205-222
γ-Melanocyte stimulating hormone (γMSH) is a possibly biologically active material discovered in the cryptic N-terminus of the pro-opiocortin precursor by recombinant DNA analysis of bovine pituitary mRNA. Well-characterized antisera to synthetic bovine γ-3MSH (γ3MSH) were used to localize immunoreactive sites in sections of formaldehyde-fixed rat brain and pituitary by the indirect immunoperoxidase technique. Specificity for staining was established by absorption with the synthetic antigen peptides or their fragments; staining was not blocked by absorption with synthetic replicates of other natural peptides that contain redundant amino acid sequences, with those of γMSH such as corticotropin or β-MSH. The general patterns of staining within adenohypophysis, intermediate lobe, and central nervous system closely followed the previously described patterns of β-endorphin immunoreactivity. Corticotrophs, all intermediate lobe cells and neuronal perikarya in the ventro-basal hypothalamus exhibited immunoreactivity for γ3MSH as they do for β-endorphin. Furthermore, the general distribution of immunoreactive nerve fibers and terminals within the diencephalon and pons was quite similar to endorphin immunoreactivity patterns as well. In series of alternating sections, prepared for either γ3MSH β-endorphin immunoreactivity, the same specific terminal fields were found to exhibit very similarly shaped varicose axons and probable terminal bouton configurations. However, the density of the innervation by fibers exhibiting immunoreactivity for the two peptides varied among the common target areas. Furthermore, the perikarya exhibiting γ3MSH immunoreactivity were fewer in number, smaller in size, and more medially clustered than those exhibiting immunoreactivity for β-endorphin. These results demonstrate that γ3MSH also occurs in rat brain and in pituitary cells which were already known to contain endorphin immunoreactivity. However, γ3MSH-immunoreactive neurones may not be coexistent with all endorphin-immunoreactive neurons, and these cells project with varying intensity to common target fields. Such observations are in agreement with the proposal of different processing of a common precursor in different cells. 相似文献
678.
Immunoreactive (IR)-gamma 3-melanotropin (MSH), -adrenocorticotropin (ACTH) and -beta-endorphin in various areas of bovine brain were measured with their respective radioimmunoassays (RIA). The concentrations of IR-gamma 3-MSH were almost the same as those of IR-ACTH in most areas. Furthermore, in all brain regions, the concentrations of both peptides were lower than those of IR-beta-endorphin. The highest concentration of IR-gamma 3-MSH was found in hypothalamus, followed by thalamus, midbrain and striatum. Gel permeation chromatographic studies showed that the main gamma 3-MSH-like peptide in the hypothalamus, striatum and midbrain was a small form, whose molecular weight is about 4500. These brain gamma 3-MSH-like peptides were also found to be glycosylated. 相似文献
679.
Rena Matsuura Mayumi Kishida Rie Konishi Yuuki Hirata Noriko Adachi Shota Segawa Kenta Imao Tsutomu Tanaka Akihiko Kondo 《Biotechnology and bioengineering》2019,116(10):2640-2651
Microbial production of 1,5-diaminopentane (DAP) from renewable feedstock is a promising and sustainable approach for the production of polyamides. In this study, we constructed a β-glucosidase (BGL)-secreting Corynebacterium glutamicum and successfully used this strain to produce DAP from cellobiose and glucose. First, C. glutamicum was metabolically engineered to produce l -lysine (a direct precursor of DAP), followed by the coexpression of l -lysine decarboxylase and BGL derived from Escherichia coli and Thermobifida fusca YX (Tfu0937), respectively. This new engineered C. glutamicum strain produced 27 g/L of DAP from cellobiose in CGXII minimal medium using fed-batch cultivation. The yield of DAP was 0.43 g/g glucose (1 g of cellobiose corresponds to 1.1 g of glucose), which is the highest yield reported to date. These results demonstrate the feasibility of DAP production from cellobiose or cellooligosaccharides using an engineered C. glutamicum strain. 相似文献
680.
Hideki Tanaka Hirotsugu Hino Shota Moriya Hiromi Kazama Masaya Miyazaki Naoharu Takano Masaki Hiramoto Kiyoaki Tsukahara Keisuke Miyazawa 《Biochemistry and Biophysics Reports》2020
Tyrosine kinase inhibitors (TKIs) induce autophagy in many types of cancer cells. We previously reported that gefitinib (GEF) and imatinib (IMA) induce autophagy in epidermal growth factor receptor (EGFR) knock-out A549 and non-BCR-ABL-expressing leukemia cell lines, respectively. This evidence suggests that TKI-induced autophagy is independent of the original target molecules. The present study compared the autophagy-inducing abilities of various TKIs, regardless of their targets, by quantitative autophagy flux assay. We established stable clones expressing the GFP-LC3-mCherry-LC3ΔG plasmid in A549, PC-9, and CAL 27 cell lines and assessed autophagy inducibility by monitoring the fluorescent ratios of GFP-LC3 to mCherry-LC3ΔG using an IncuCyte live cell imaging system during exposure to TKIs viz; GEF, osimertinib (OSI), lapatinib (LAP), lenvatinib (LEN), sorafenib (SOR), IMA, dasatinib (DAS), and tivantinib (TIV). Among these TKIs, DAS, GEF, and SOR exhibited prominent autophagy induction in A549 and PC-9 cells. In CAL 27 cells, IMA, SOR, and LEN, but not GEF, TIV, or OSI, exhibited autophagy induction. In the presence of azithromycin (AZM), which showed an inhibitory effect on autophagy flux, TKIs with prominent autophagy inducibility exhibited enhanced cytotoxicity via non-apoptotic cell death relative to effects of TKI alone. Therefore, autophagy inducibility of TKIs differed in the context of cancer cells. However, once induced, they appeared to have cytoprotective functions. Thus, blocking TKI-induced autophagy with AZM may improve the therapeutic effect of TKIs in cancer cells. 相似文献