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81.
82.
Koizumi M Akahori K Ohmine T Tsutsumi S Sone J Kosaka T Kaneko M Kimura S Shimada K 《Bioorganic & medicinal chemistry letters》2000,10(19):2213-2216
2'-Deoxyguanosine residues of a 3',5'-end-modified hexadeoxyribonucleotide (R-95288) with anti-HIV-1 activity were substituted with N2-methyl-2'-deoxyguanosine (m2dG). These modified oligodeoxyribonucleotides (ODNs) showed a 2-fold higher activity than R-95288. Also, the CD spectra of these ODNs indicated that the m2dG modification stabilized the tertiary structure of the G-quadruplex. 相似文献
83.
Ghosh PK Ventura GJ Gupta S Serrano J Tsutsumi V Ortiz-Ortiz L 《The Journal of eukaryotic microbiology》2000,47(4):395-399
Distribution of immune cell populations was studied in a C3H/HeJ mouse model of intestinal amebiasis from 5 to 60 days post-inoculation with Entamoeba histolytica, using immunoperoxidase techniques. At various time intervals, the ceca from mice were fixed in 10% formalin, dehydrated, embedded and sectioned at 5 microm. Sections were incubated with conjugated peroxidase-labelled antibodies to mouse IgA, IgM, and IgG. Color was developed with 3, 3'-diaminobenzidine tetrahydrochloride (DAB)/H2O2 solution. CD3, CD4, and CD8 cells, as well as neutrophils were detected by reacting with biotin-conjugated anti-mouse CD3, CD4, CD8, and CD11 monoclonal antibodies, followed by their incubation with avidin-peroxidase and color development with DAB/H2O2 solution. Erythrocin B and toluidine blue were used to stain eosinophils and Mast cells, respectively. It was observed that the IgA+ plasma cell was the dominating immune cell present in the mucosa, although eosinophils, neutrophils, CD3+, CD4+, CD8+, IgM+, IgG+ cells and Mast cells were also seen. Results of this study suggest that infiltration of immune cells at the mucosal surface during intestinal amebiasis might be important in the defense against this parasite. 相似文献
84.
Mizunuma M Yanai A Tsutsumi S Yoshida H Seno H Inoue M Nishida M 《Plastic and reconstructive surgery》2000,106(4):845-8; discussion 849-51
Dog-ear formation is often unavoidable with resection and suturing of the skin, including spindle excision. Regarding dog-ear formation after basic spindle skin resection during removal of a round tumor of the skin, we quantitatively analyzed the frequency of dog-ear formation with respect to the following three techniques: previous spindle skin resection, S-shaped skin resection, which has been experientially considered to induce limited deformity, and mosque-shaped skin resection for control. To date, by using paper models or sponges, various techniques of skin resection have been simulated in the field of plastic surgery. In the present study, we performed three-dimensional simulation and analyzed three different techniques of skin resection by using the finite element method. As a result, image simulation demonstrated that the frequency of dog-ear formation was limited by S-shaped, spindle, and mosque-shaped skin resection, in descending order. 相似文献
85.
Lilia Gonzalez-Ceron Mario H Rodriguez Robert A Wirtz Barbara J Sina Olga L Palomeque Jose A Nettel Victor Tsutsumi 《Experimental parasitology》1998,90(3):203-211
Gonzalez-Ceron, L., Rodriguez, M. H., Wirtz, R. A., Sina, B. J., Palomeque, O. L., Nettel, J. A., and Tsutsumi, V. 1998.Plasmodium vivax:A monoclonal antibody recognizes a circumsporozoite protein precursor on the sporozoite surface.Experimental Parasitology90, 203–211. The major surface circumsporozoite (CS) proteins are known to play a role in malaria sporozoite development and invasion of invertebrate and vertebrate host cells.Plasmodium vivaxCS protein processing during mosquito midgut oocyst and salivary gland sporozoite development was studied using monoclonal antibodies which recognize different CS protein epitopes. Monoclonal antibodies which react with the CS amino acid repeat sequences by ELISA recognized a 50-kDa precursor protein in immature oocyst and additional 47- and 42-kDa proteins in older oocysts. A 42-kDa CS protein was detected after initial sporozoite invasion of mosquito salivary glands and an additional 50-kDa precursor CS protein observed later in infected salivary glands. These data confirm previous results with otherPlasmodiumspecies, in which more CS protein precursors were detected in oocysts than in salivary gland sporozoites. A monoclonal antibody (PvPCS) was characterized which reacts with an epitope found only in the 50-kDa precursor CS protein. PvPCS reacted with allP. vivaxsporozoite strains tested by indirect immunofluorescent assay, homogeneously staining the sporozoite periphery with much lower intensity than that produced by anti-CS repeat antibodies. Immunoelectron microscopy using PvPCS showed that the CS protein precursor was associated with peripheral cytoplasmic vacuoles and membranes of sporoblast and budding sporozoites in development oocysts. In salivary gland sporozoites, the CS protein precursor was primarily associated with micronemes and sporozoite membranes. Our results suggest that the 50-kDa CS protein precursor is synthesized intracellularly and secreted on the membrane surface, where it is proteolytically processed to form the 42-kDa mature CS protein. These data indicate that differences in CS protein processing in oocyst and salivary gland sporozoites development may occur. 相似文献
86.
Zhang D Kato Y Zhang L Fujimoto M Tsutsumi N Sodmergen Sakamoto W 《The Plant cell》2010,22(11):3710-3725
FtsH is an ATP-dependent metalloprotease present as a hexameric heterocomplex in thylakoid membranes. Encoded in the Arabidopsis thaliana YELLOW VARIEGATED2 (VAR2) locus, FtsH2 is one isoform among major Type A (FtsH1/5) and Type B (FtsH2/8) isomers. Mutants lacking FtsH2 (var2) and FtsH5 (var1) are characterized by a typical leaf-variegated phenotype. The functional importance of the catalytic center (comprised by the zinc binding domain) in FtsH2 was assessed in this study by generating transgenic plants that ectopically expressed FtsH2(488), a proteolytically inactive version of FtsH2. The resulting amino acid substitution inhibited FtsH protease activity in vivo when introduced into Escherichia coli FtsH. By contrast, expression of FtsH2(488) rescued not only leaf variegation in var2 but also seedling lethality in var2 ftsh8, suggesting that the protease activity of Type B isomers is completely dispensable, which implies that the chloroplastic FtsH complex has protease sites in excess and that they act redundantly rather than coordinately. However, expression of FtsH2(488) did not fully rescue leaf variegation in var1 var2 because the overall FtsH levels were reduced under this background. Applying an inducible promoter to our complementation analysis revealed that rescue of leaf variegation indeed depends on the overall amount of FtsH. Our results elucidate protein activity and its amount as important factors for the function of FtsH heterocomplexes that are composed of multiple isoforms in the thylakoid membrane. 相似文献
87.
Masaki Hizume Atsushi Kobayashi Tetsuyuki Kitamoto 《Biochemical and biophysical research communications》2010,391(4):1681-1686
Prion protein (PrP) is a glycosylphosphatidylinositol (GPI)-anchored protein, and the C-terminal GPI anchor signal sequence (GPI-SS) of PrP is cleaved before GPI anchoring. However, mutations near the GPI anchor attachment site (the ω site) in the GPI-SS have been recognized in human genetic prion diseases. Moreover, the ω site of PrP has not been identified except hamster, though it is known that amino acid restrictions are very severe at the ω and ω + 2 sites in other GPI-anchored proteins. To investigate the effect of mutations near the ω site of PrP on the conversion and the GPI anchoring, and to discover the ω site of murine PrP, we systematically created mutant murine PrP with all possible single amino acid substitutions at every amino acid residue from codon 228 to 240. We transfected them into scrapie-infected mouse neuroblastoma cells and examined the conversion efficiencies and the GPI anchoring of each mutant PrP. Mutations near the ω site altered the conversion efficiencies and the GPI anchoring efficiencies. Especially, amino acid restrictions for the conversion and the GPI anchoring were severe at codons 230 and 232 in murine PrP, though they were less severe than in other GPI-anchored proteins. Only the mutant PrPs presented on a cell surface via a GPI anchor were conversion competent. The present study shows that mutations in the GPI-SS can affect the GPI anchoring and the conversion efficiency of PrP. We clarified for the first time the ω site of murine PrP and the amino acid conditions near the ω site for the conversion as well as GPI anchoring. 相似文献
88.
The composition of the rumen ciliate fauna in 76 Kafue lechwe inhabiting a limited area in Zambia was surveyed and five genera containing 24 species with 16 formae belonging to the family Ophryoscolecidae were identified. Four new species belonging to Diplodiniinae were recognized and described as Diplodinium lochinvarense n. sp., Diplodinium leche n. sp., Diplodinium zambiense n. sp., and Metadinium ossiculi n. sp. In addition, Ostracodinium gracile form fissilaminatum Dogiel, 1932 was found for the second time and described as Metadinium fissilaminatum n. comb. The species composition was fairly unusual. Seven of the species have been found only in African wild antelopes and these species were found more frequently than cosmopolitan species. There was no evidence of isotrichid species. The average density of ciliates per 1 ml of the rumen fluid was 25.7 x 10(4), and the number of ciliate species per head of host was 10.8. 相似文献
89.
N Nakamura Y Tsutsumi S Kimata M Sawada G Hasegawa Y Kitagawa K Nakano M Kondo H Nakao S Makino 《Endocrinologia japonica》1991,38(5):523-526
To determine whether environmental factors could affect the incidence of diabetes in RT6.1+ lymphocytes-depleted diabetes resistant (DR) BB rats, we tested polyinosinic-polycytidylic acid (Poly I:C), as an immune activator, in conjunction with anti-RT6.1 antibody in DR-BB rats which were bred in a specific pathogen free (SPF) condition. Diabetes was induced by the combined administration of poly I:C and anti-RT6.1 antibody. The use of poly I:C or anti-RT6.1 antibody alone did not cause diabetes. These results suggest that RT6.1+ T lymphocytes regulate autoimmune diabetes and that non-specific immune activation caused by environmental factors plays a key role in inducing diabetes in DR-BB rats. 相似文献
90.
Kawaguchi A Asano H Matsushima K Wada T Yoshida S Ichida S 《Neurochemical research》2007,32(9):1469-1475
It is well known that morphological and functional changes during neural differentiation sometimes accompany the expression
of various voltage-gated ion channels. In this work, we investigated whether the enhancement of sodium current in differentiated
neuroblastoma × glioma NG108-15 cells treated with dibutyryl cAMP is related to the expression of voltage-gated sodium channels.
The results were as follows. (1) Sodium current density on peak voltage in differentiated cells was significantly enhanced
compared with that in undifferentiated cells, as detected by the whole-cell patch clamp method. The steady-state inactivation
curve in differentiated cells was similar to that for undifferentiated cells, but a hyperpolarized shift in the activation
curve for differentiated cells was observed. The sodium currents of differentiated and undifferentiated cells were completely
inhibited by 10−7 M tetrodotoxin (TTX). (2) The only NaV mRNA with an increased expression level during neuronal differentiation was that for NaV1.7, as observed by real-time PCR analysis. (3) The increase in the level of NaV1.7 α subunit expression during neuronal differentiation was also observed by immunocytochemistry; in particular, the localization
of NaV1.7 α subunits on the soma, varicosities and growth cone was significant. These results suggest that the enhancement of TTX-sensitive
sodium current density in differentiated NG108-15 cells is mainly due to the increase in the expression of the TTX-sensitive
voltage-gated Na+ channel, NaV1.7. 相似文献