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111.
A polyphenol oxidase (o-diphenol oxidase) [o-diphenol: O2 oxidoreductase E. C. 1.10. 3.1] from sweet potato named component IIb was highly purified. The copper content of this enzyme was measured by neutron activation analysis. Samples were analyzed with or without chemical separation after neutron irradiation. The copper content of the enzyme was determined to be 0.27%, and the minimum molecular weight of this enzyme was caluculated to be 23,500. 相似文献
112.
Yamaguchi Y Shinotsuka N Nonomura K Takemoto K Kuida K Yosida H Miura M 《The Journal of cell biology》2011,195(6):1047-1060
Many cells die during development, tissue homeostasis, and disease. Dysregulation of apoptosis leads to cranial neural tube closure (NTC) defects like exencephaly, although the mechanism is unclear. Observing cells undergoing apoptosis in a living context could help elucidate their origin, behavior, and influence on surrounding tissues, but few tools are available for this purpose, especially in mammals. In this paper, we used insulator sequences to generate a transgenic mouse that stably expressed a genetically encoded fluorescence resonance energy transfer (FRET)-based fluorescent reporter for caspase activation and performed simultaneous time-lapse imaging of apoptosis and morphogenesis in living embryos. Live FRET imaging with a fast-scanning confocal microscope revealed that cells containing activated caspases showed typical and nontypical apoptotic behavior in a region-specific manner during NTC. Inhibiting caspase activation perturbed and delayed the smooth progression of cranial NTC, which might increase the risk of exencephaly. Our results suggest that caspase-mediated cell removal facilitates NTC completion within a limited developmental window. 相似文献
113.
Hirayama J Eda S Mitsui H Minamisawa K 《Applied and environmental microbiology》2011,77(24):8787-8790
In the presence of nitrate, N2O emission increased markedly from soybean roots inoculated with nosZ mutant of Bradyrhizobium japonicum, but not from soybean roots inoculated with a napA nosZ double mutant, indicating that B. japonicum bacteroids in soybean nodules are able to convert the exogenously supplied nitrate into N2O via a denitrification pathway. 相似文献
114.
Brandl R Hyodo F Korff-Schmising Mv Maekawa K Miura T Takematsu Y Matsumoto T Abe T Bagine R Kaib M 《Molecular phylogenetics and evolution》2007,45(1):239-250
The evolution of fungus-growing termites is supposed to have started in the African rain forests with multiple invasions of semi-arid habitats as well as multiple invasions of the Oriental region. We used sequences of the mitochondrial COII gene and Bayesian dating to investigate the time frame of the evolution of Macrotermes, an important genus of fungus-growing termites. We found that the genus Macrotermes consists of at least 6 distantly related clades. Furthermore, the COII sequences suggested some cryptic diversity within the analysed African Macrotermes species. The dates calculated with the COII data using a fossilized termite mound to calibrate the clock were in good agreement with dates calculated with COI sequences using the split between Locusta and Chortippus as calibration point which supports the consistency of the calibration points. The clades from the Oriental region dated back to the early Tertiary. These estimates of divergence times suggested that Macrotermes invaded Asia during periods with humid climates. For Africa, many speciation events predated the Pleistocene and fall in range of 6-23 million years ago. These estimates suggest that savannah-adapted African clades radiated with the spread of the semi-arid ecosystems during the Miocene. Apparently, events during the Pleistocene were of little importance for speciation within the genus Macrotermes. However, further investigations are necessary to increase the number of taxa for phylogenetic analysis. 相似文献
115.
Rahman Md. Lutfur Hyodo Toshinori Hasan Muhammad Nazmul Mihara Yuko Karnan Sivasundaram Ota Akinobu Tsuzuki Shinobu Hosokawa Yoshitaka Konishi Hiroyuki 《Molecular biology reports》2022,49(7):6241-6248
Molecular Biology Reports - Targeted knock-in assisted by the CRISPR/Cas9 system is an advanced technology with promising applications in various research fields including medical and agricultural... 相似文献
116.
Yuko Takahara Masao Maeda Hitoki Hasegawa Satoko Ito Toshinori Hyodo Eri Asano Masahide Takahashi Michinari Hamaguchi Takeshi Senga 《Molecular and cellular biochemistry》2014,389(1-2):9-16
Membrane blebs are round-shaped dynamic membrane protrusions that occur under many physiological conditions. Membrane bleb production is primarily controlled by actin cytoskeletal rearrangements mediated by RhoA. Tre2–Bub2–Cdc16 (TBC) domain-containing proteins are negative regulators of the Rab family of small GTPases and contain a highly conserved TBC domain. In this report, we show that the expression of TBC1D15 is associated with the activity of RhoA and the production of membrane blebs. Depletion of TBC1D15 induced activation of RhoA and membrane blebbing, which was abolished by the addition of an inhibitor for RhoA signaling. In addition, we show that TBC1D15 is required for the accumulation of RhoA at the equatorial cortex for the ingression of the cytokinetic furrow during cytokinesis. Our results demonstrate a novel role for TBC1D15 in the regulation of RhoA during membrane blebbing and cytokinesis. 相似文献
117.
Hirotoshi Matsumura Kiwamu Umezawa Kouta Takeda Naohisa Sugimoto Takuya Ishida Masahiro Samejima Hiroyuki Ohno Makoto Yoshida Kiyohiko Igarashi Nobuhumi Nakamura 《PloS one》2014,9(8)
Pyrroloquinoline quinone (PQQ) is a redox cofactor utilized by a number of prokaryotic dehydrogenases. Not all prokaryotic organisms are capable of synthesizing PQQ, even though it plays important roles in the growth and development of many organisms, including humans. The existence of PQQ-dependent enzymes in eukaryotes has been suggested based on homology studies or the presence of PQQ-binding motifs, but there has been no evidence that such enzymes utilize PQQ as a redox cofactor. However, during our studies of hemoproteins, we fortuitously discovered a novel PQQ-dependent sugar oxidoreductase in a mushroom, the basidiomycete Coprinopsis cinerea. The enzyme protein has a signal peptide for extracellular secretion and a domain for adsorption on cellulose, in addition to the PQQ-dependent sugar dehydrogenase and cytochrome domains. Although this enzyme shows low amino acid sequence homology with known PQQ-dependent enzymes, it strongly binds PQQ and shows PQQ-dependent activity. BLAST search uncovered the existence of many genes encoding homologous proteins in bacteria, archaea, amoebozoa, and fungi, and phylogenetic analysis suggested that these quinoproteins may be members of a new family that is widely distributed not only in prokaryotes, but also in eukaryotes. 相似文献
118.
Takabe S Teranishi K Takaki S Kusakabe M Hirose S Kaneko T Hyodo S 《Cell and tissue research》2012,348(1):141-153
In teleost fishes, it is well-established that the gill serves as an important ionoregulatory organ in addition to its primary
function of respiratory gas exchange. In elasmobranch fish, however, the ionoregulatory function of the gills is still poorly
understood. Although mitochondria-rich (MR) cells have also been found in elasmobranch fish, these cells are considered to
function primarily in acid-base regulation. In this study, we found a novel aggregate structure made up of cells with basolaterally-expressed
Na+/K+-ATPase (NKA), in addition to NKA-immunoreactive MR cells that have already been described in the gill filament and lamella.
The cell aggregates, named follicularly-arranged NKA-rich cells (follicular NRCs), were found exclusively in the epithelial
lining of the venous web in the cavernous region of the filament and the inter-filamental space of the gill septum. The follicular
NRCs form a single-layered follicular structure with a large lumen leading to the external environment. The follicular NRCs
were characterized by: (i) well-developed microvilli on the apical membrane, (ii) less prominent infoldings of the basolateral
membrane and (iii) typical junction structures including deep tight junction between cells. In addition, large numbers of
vesicles were observed in the cytoplasm and some of them were fused to the lateral membrane. The follicular NRCs expressed
Na+/H+ exchanger 3 and Ca2+ transporter 1. The follicular NRCs thus have the characteristics of absorptive ionoregulatory cells and this suggests that
the elasmobranch gill probably contributes more importantly to body fluid homeostasis than previously thought. 相似文献
119.