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991.
Rodent mandibular incisors have a unique anatomical structure that allows teeth to grow throughout the lifetime of the rodent. This report presents a novel transplantation technique for studying the apical bud differentiation of rodent mandibular incisors. Incisal apical end tissue with green fluorescent protein from transgenic mouse was transplanted to wild type mice, and the development of the transplanted cells were immunohistologically observed for 12 weeks after the transplantation. Results indicate that the green fluorescent apical end tissue replaced the original tissue, and cells from the apical bud differentiated and extended toward the incisal edge direction. The immunostaining with podoplanin also showed that the characteristics of the green fluorescent tissue were identical to those of the original. The green fluorescent cells were only found in the labial side of the incisor up to 4 weeks. After 12 weeks, however, they were also found in the lingual side. Here the green fluorescent cementocyte-like cells were only present in the cementum close to the dentin surface. This study suggests that some of the cells that form the cellular cementum come from the apical tissue including the apical bud in rodent incisors. 相似文献
992.
Kazutaka Ikegashira Taku Ikenogami Takayuki Yamasaki Takahiro Oka Yasunori Hase Naoki Miyagawa Koji Inagaki Iichiro Kawahara Yoshihisa Koga Hiromasa Hashimoto 《Bioorganic & medicinal chemistry letters》2019,29(7):873-877
Optimization of novel azetidine compounds, which we had found as colony stimulating factor-1 receptor (CSF-1R) Type II inhibitors, provided JTE-952 as a clinical candidate with high cellular activity (IC50?=?20?nM) and good pharmacokinetics profile. JTE-952 was also effective against a mouse collagen-induced model of arthritis (mouse CIA-model). Additionally, the X-ray co-crystal structure of JTE-952 with CSF-1R protein was shown to be a Type II inhibitor, and the kinase panel assay indicated that JTE-952 had high kinase selectivity. 相似文献
993.
The reproductive modes of the Scorpaenidae are extremely varied: oviparity, viviparity, and even spawning of internally fertilized
eggs or embryos (zygoparity or embryoparity), as in Helicolenus, are known. The ovarian structure of this family is divided into two types by the arrangement of the stroma and the ovarian
cavity. One type is the ovary in which the lamella-like stroma develops from the ovarian hilus located on the dorsal side
and where the ovarian cavity is located on the ventral side of ovary, classified as “cystovarian type II-1” by Takano (1989).
In the other type, the stroma in the ovary develops radially around the blood circulatory system that traverses the center
of the ovary, and then the ovarian cavity surrounds all the ovary, classified as “cystovarian type II-3” by Takano (1989).
In the present analysis, previous reports about ovarian structure and the relationship to the reproductive mode of scorpaenids
were described, and the ovarian structure of eight genera of Scorpaenidae was examined. The ovary of cystovarian type II-1
is seen only in viviparous genera and is not seen in oviparous genera. However, the cystovarian type II-1 is a general structure
in other families of Scorpaeniformes, and this structure could be considered a primitive type of ovary rather than that acquired
by the process of evolution from oviparity to viviparity. The ovary of cystovarian type II-3 is seen in all six oviparous
genera and the one zygoparous genus examined. The ovary of this type is not found in any other family of teleosts, so it could
be a structure originally divided in Scorpaenidae. In the genera having the cystovarian type II-3 ovary, there is a common
feature of spawning: a floating egg mass encompassed by the gelatinous material. We postulate that the evolution of reproductive
mode in the scorpaenid fishes is as follows: Sebastes and Sebastiscus have a primitive ovary in which viviparity has developed, whereas the genera that spawn a floating egg mass evolved the ovarian
structure from primitive type to cystovarian type II-3, and further zygoparity, such as in Helicolenus, evolved from them. 相似文献
994.
995.
Kimura N Ohmori K Miyazaki K Izawa M Matsuzaki Y Yasuda Y Takematsu H Kozutsumi Y Moriyama A Kannagi R 《The Journal of biological chemistry》2007,282(44):32200-32207
CD22/Siglec-2, an important inhibitory co-receptor on B-lymphocytes, is known to recognize alpha2-6-sialylated glycan as a specific ligand. Here we propose that the alpha2-6-sialylated and 6-GlcNAc-sulfated determinant serves as a preferred ligand for CD22 because the binding of a human B-cell line to CD22 was almost completely abrogated after incubating the cells with NaClO3, an inhibitor of cellular sulfate metabolism, and was also significantly inhibited by a newly generated monoclonal antibody specific to the alpha2-6-sialylated 6-sulfo-N-acetyllactosamine (LacNAc) determinant (KN343, murine IgM). The alpha2-6-sialylated 6-sulfo-LacNAc determinant defined by the antibody was significantly expressed on a majority of normal human peripheral B-lymphocytes as well as follicular B-lymphocytes in peripheral lymph nodes. The determinant was also expressed in endothelial cells of high endothelial venules of secondary lymphoid tissues, including lymph nodes, tonsils, and intestine-associated lymphoid tissues, more strongly than on B-lymphocytes, suggesting a role for CD22 in B-cell interaction with blood vessels and trafficking. These results indicate that the alpha2-6-sialylated 6-sulfo-LacNAc determinant serves as an endogenous ligand for human CD22 and suggest the possibility that 6-GlcNAc sulfation as well as alpha2-6-sialylation may regulate CD22/Siglec-2 functions in humans. 相似文献
996.
997.
Yasunori Muraosa Kyoko Morimoto Ayako Sano Kazuko Nishimura Kishio Hatai 《Mycoscience》2009,50(2):106-115
Four strains belonging to the Peronosporomycetes (formerly Oomycetes) were isolated from white nodules found on the mantle
of three species of abalone. In artificial seawater, the four isolates formed fragments such as in the genus Haliphthoros, but the protoplasm constriction was weaker, and fragments were longer, with smaller spaces between them, than those of Haliphthoros. The four strains form one or more discharge tubes from each zoosporangium. The four strains were similar, but not identical,
to the genus Haliphthoros based on morphological characteristics. As a result, the four isolates were classified in a new genus and species, Halioticida noduliformans gen. et sp. nov. Phylogenetic analysis of the D1/D2 region of the large subunit ribosomal RNA gene (LSU rDNA) was performed,
and the four isolates showed 100%–99.8% concordance. In the phylogenetic tree, the four isolates were not classified in the
subclass Peronosporomycetidae, Saprolegniomycetidae, or Rhipidiomycetidae. However, the four isolates formed a new clade with
genera Haliphthoros and Halocrusticida in Peronosporomycetes. Within this new clade, the four isolates, Haliphthoros spp. and Halocrusticida spp., were grouped in their respective independent subclades. These results showed that these were the new genus and species
from the morphological characteristics. 相似文献
998.
999.
Calreticulin (CRT) is a major calcium-sequestering protein in the endoplasmic reticulum and has been implicated in a variety
of cellular functions. To analyze the function of CRT in rice, a yeast two-hybrid protein interaction assay was used for identifying
interacting proteins. Fourteen of 17 interacting cDNA clones found coded for a novel histidine- and alanine-rich protein (OsHARP)
of 342 amino acid residues. The mRNA expression level of OsHARP was up-regulated in rice seedlings treated with gibberellin
(GA), but not ABA and showed a similar pattern as OsCRT mRNA. Rice plants transformed with the OsHARP promoter-GUS construct
showed GUS staining in the basal parts of leaf sheaths, and although GUS activity increased when treated with GA3, it was not as high an increase as when mRNA was analyzed. To elucidate the role of OsHARP in leaf sheath elongation, antisense
OsHARP transgenic rice lines were constructed. The antisense OsHARP transgenic rice plants were consistently shorter than
the vector control under normal conditions. To examine whether OsHARP expression would affect other proteins, basal leaf sheaths
from antisense OsHARP transgenic rice plants were analyzed using proteomic techniques. In antisense transgenic-rice OsHARP
plants, OsCRT was down-regulated and the levels of 20 other proteins were changed compared to the pattern of the vector control.
These results signify an important role of HARP in rice leaf sheath cell division or elongation and suggest that CRT may interact
with HARP during certain stages of development. 相似文献
1000.
Adachi T Sato C Kishi Y Totani K Murata T Usui T Kitajima K 《Glycoconjugate journal》2009,26(3):285-299
Formation of membrane microdomain is critical for cell migration (epiboly) during gastrulation of medaka fish [Adachi et al. (Biochem. Biophys. Res. Commun. 358:848–853, 2007)]. In this study, we characterized membrane microdomain from gastrula embryos to understand its roles in epiboly. A cell
adhesion molecule (E-cadherin), its associated protein (β-catenin), transducer proteins (PLCγ, cSrc), and a cytoskeleton protein
(β-actin) were enriched in the membrane microdomain. LeX-containing glycolipids and glycoproteins (LeX-gp) were exclusively enriched in the membrane microdomain. Interestingly, the isolated membrane microdomain had the ability
to bind to each other in the presence of Ca2+. This membrane microdomain binding was achieved through the E-cadherin homophilic and the LeX-glycan-mediated interactions. E-cadherin and LeX-gp were co-localized on the same membrane microdomain, suggesting that these two interactions are operative at the same time.
Thus, the membrane microdomain functions as a platform of the E-cadherin- and LeX-glycan-mediated cell adhesion and signal transduction.
相似文献
Ken KitajimaEmail: |