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111.
Bioaugmentation and coexistence of two functionally similar bacterial strains in aerobic granules 总被引:2,自引:0,他引:2
The survival of the inoculated microbial culture is critical for successful bioaugmentation but impossible to predict precisely.
As an alternative strategy, bioaugmentation of a group of microorganisms may improve reliability of bioaugmentation. This
study evaluated simultaneous bioaugmentation of two functionally similar bacterial strains in aerobic granules. The two strains,
Pandoraea sp. PG-01 and Rhodococcus erythropolis PG-03, showed high phenol degradation and growth rates in phenol medium, but they were characterized as having a poor aggregation
activity and weak bioflocculant-producing and biofilm-forming abilities. In the spatially homogeneous batch conditions, strain
PG-01 with higher growth rates outcompeted strain PG-03. However, the two strains could stably coexist in the spatially heterogeneous
conditions. Then the two strains were mixed and bioaugmented into activated sludge in two sequencing batch reactors, which
were operated with the different settling times of 5 and 30 min, respectively. Aerobic granules were developed only in the
reactor with a settling time of 5 min. Fluorescence in situ hybridization and denaturing gradient gel electrophoresis showed
that the two strains could coexist in aerobic granules but not in activated sludge. These findings suggested that the compact
structure of aerobic granules provided spatial isolation for coexistence of competitively superior and inferior strains with
similar functions. 相似文献
112.
Two isoforms of the cold-inducible mRNA-binding protein RBM3 localize to dendrites and promote translation 总被引:1,自引:0,他引:1
Smart F Aschrafi A Atkins A Owens GC Pilotte J Cunningham BA Vanderklish PW 《Journal of neurochemistry》2007,101(5):1367-1379
A diverse set of mRNA-binding proteins (BPs) regulate local translation in neurons. However, little is known about the role(s) played by a family of cold-inducible, glycine-rich mRNA-BPs. Unlike neuronal mRNA-BPs characterized thus far, these proteins are induced by hypothermia and are comprised of one RNA recognition motif and an adjacent arginine- and glycine-rich domain. We studied the expression and function of the RNA-binding motif protein 3 (RBM3), a member of this family, in neurons. RBM3 was expressed in multiple brain regions, with the highest levels in cerebellum and olfactory bulb. In dissociated neurons, RBM3 was observed in nuclei and in a heterogeneous population of granules within dendrites. In sucrose gradient assays, RBM3 cofractionated with heavy mRNA granules and multiple components of the translation machinery. Two alternatively spliced RBM3 isoforms that differed by a single arginine residue were identified in neurons; both were post-translationally modified. The variant lacking the spliced arginine exhibited a higher dendritic localization and was the only isoform present in astrocytes. When overexpressed in neuronal cell lines, RBM3 isoforms-enhanced global translation, the formation of active polysomes, and the activation of initiation factors. These data suggest that RBM3 plays a distinctive role in enhancing translation in neurons. 相似文献
113.
Xue X Yang H Shen W Zhao Q Li J Yang K Chen C Jin Y Bartlam M Rao Z 《Journal of molecular biology》2007,366(3):965-975
The viral proteases have proven to be the most selective and useful for removing the fusion tags in fusion protein expression systems. As a key enzyme in the viral life-cycle, the main protease (M(pro)) is most attractive for drug design targeting the SARS coronavirus (SARS-CoV), the etiological agent responsible for the outbreak of severe acute respiratory syndrome (SARS) in 2003. In this study, SARS-CoV M(pro) was used to specifically remove the GST tag in a new fusion protein expression system. We report a new method to produce wild-type (WT) SARS-CoV M(pro) with authentic N and C termini, and compare the activity of WT protease with those of three different types of SARS-CoV M(pro) with additional residues at the N or C terminus. Our results show that additional residues at the N terminus, but not at the C terminus, of M(pro) are detrimental to enzyme activity. To explain this, the crystal structures of WT SARS-CoV M(pro) and its complex with a Michael acceptor inhibitor were determined to 1.6 Angstroms and 1.95 Angstroms resolution respectively. These crystal structures reveal that the first residue of this protease is important for sustaining the substrate-binding pocket and inhibitor binding. This study suggests that SARS-CoV M(pro) could serve as a new tag-cleavage endopeptidase for protein overproduction, and the WT SARS-CoV M(pro) is more appropriate for mechanistic characterization and inhibitor design. 相似文献
114.
废橡胶颗粒浸提液物质释放及其浸种对草坪植物生长的影响 总被引:3,自引:0,他引:3
纯胶粒浸提液、胶粒与壤土混合的浸提液中重金属含量分析表明,纯胶粒浸提液中Zn含量最高,其次为Pb,而Cd与Cu最少;与纯胶粒浸提液相比,胶粒与壤土混合的浸提液中Zn含量显著降低.紫外吸收光谱图显示,胶粒粒径越小,浸提液中有机物越复杂.用4种不同粒径胶粒的浸提液对2种草坪植物种子浸种处理后进行培养,研究了草坪植物的生长效应.结果表明,胶粒浸提液浸种对2种草坪植物的种子萌发率影响不大,但对株高产生不同的影响.对黑麦草而言,以2~4 mm胶粒浸提液浸种的株高为最高,1~2和4~6 mm胶粒浸提液浸种株高与之差异较大,分别降低1.52和1.32 cm,但均与对照无显著差异.对于高羊茅,以粒径1~2 mm胶粒浸提液浸种的株高为最低,比对照降低了18.76%,其它处理间无明显差异.浸提液浸种对黑麦草地下生物量有明显的抑制作用,但对根长生长有促进作用.胶粒浸提液浸种对2种草坪植物的地上生物量无明显影响.从胶粒浸提液的物质释放及其浸种对草坪植物生长的影响来看,废胶粒可用于运动场草坪的基质组配. 相似文献
115.
In this study, morphological alterations, biomass growth, and secondary metabolite production of genetically transformed hairy
roots ofPanax ginseng C. A. Meyer, were evaluated after administration of plant growth regulators. The addition of benzylamino purine and kinetin
to the culture media increased biomass formation and phenolic compound biosynthesis in the hairy roots. α-Naphthaleneacetic
acid and indole-3-butyric acid inhibited hairy root growth, however, low concentrations of indole-3-acetic acid slightly increased
hairy root growth. Low concentrations of 2,4-Dichlorophenoxyacetic acid profoundly inhibited growth of hairy roots. The addition
of plant growth regulators, such as auxin, did not increase total phenolic compounds in hairy roots that did not contain gibberellic
acid and cytokinins. Callus formation was induced in cultures suspended in liquid medium amended with benzylamino purine and
kinetin. Hairy roots regenerated from these calluses exhibited an active growth pattern with extensive lateral branching in
non-amended medium, similar to the growth pattern of the original hairy roots. 相似文献
116.
The quality of pharmaceutical products such as ginseng is important for ensuring consumer safety and efficacy. Ginseng is
an expensive herb, and adulteration with other cheaper products may occur. Quality assurance of ginseng is needed since many
of its commercial products now come in various formulations such as capsules, powder, softgels and tea. Thus traditional means
of authentication via smell, taste or physical appearance are hardly reliable. Herbs like ginseng tend to exhibit characteristic
infrared fingerprints due to their different chemical constituents. Here we report for the first time a rapid means of distinguishing
American and Asian ginsengs from two morphological fakes – sawdust and Platycodon grandiflorum, via pattern differences and principal component analysis of their infrared spectra. Our results show that ginseng can be
distinguished from both sawdust and Platycodon grandiflorum, hence there is a potential of using infrared spectroscopy as a novel analytical technique in the authentication of ginseng. 相似文献
117.
The purpose of this research was to develop and optimize a controlled-release multiunit floating system of a highly water
soluble drug, ranitidine HCl, using Compritol, Gelucire 50/13, and Gelucire 43/01 as lipid carriers. Ranitidine HCl-lipid
granules were prepared by the melt granulation technique and evaluated for in vitro floating and drug release. ethyl cellulose,
methylcellulose, and hydroxypropyl methylcellulose were evaluated as release rate modifiers. A 32 full factorial design was used for optimization by taking the amounts of Gelucire 43/01 (X
1) and ethyl cellulose (X
2) as independent variables, and the percentage drug released in 1(Q1), 5(Q5), and 10 (Q10) hours as dependent variables. The results revealed that the moderate amount of Gelucire 43/01 and ethyl cellulose provides
desired release of ranitidine hydrochloride from a floating system. Batch F4 was considered optimum since it contained less
Gelucire and was more similar to the theoretically predicted dissolution profile (f2=62.43). The temperature sensitivity studies for the prepared formulations at 40°C/75% relative humidity for 3 months showed
no significant change in in vitro drug release pattern. These studies indicate that the hydrophobic lipid Gelucire 43/01 can
be considered an effective carrier for design of a multiunit floating drug delivery system for highly water soluble drugs
such as ranitidine HCl.
Published: April 13, 2007 相似文献
118.
An increasing number of medically important proteins are challenging drug targets because their binding sites are too shallow or too polar, are cryptic and thus not detectable without a bound ligand or located in a protein–protein interface. While such proteins may not bind druglike small molecules with sufficiently high affinity, they are frequently druggable using novel therapeutic modalities. The need for such modalities can be determined by experimental or computational fragment based methods. Computational mapping by mixed solvent molecular dynamics simulations or the FTMap server can be used to determine binding hot spots. The strength and location of the hot spots provide very useful information for selecting potentially successful approaches to drug discovery. 相似文献
119.
Hiroshi Gomi Satomi Morikawa Naoki Shinmura Hiroaki Moki Tadashi Yasui Azuma Tsukise Seiji Torii Tsuyoshi Watanabe Yoshinori Maeda Masahiro Hosaka 《The journal of histochemistry and cytochemistry》2015,63(5):350-366
The expression of secretogranin III (SgIII) in chicken endocrine cells has not been investigated. There is limited data available for the immunohistochemical localization of SgIII in the brain, pituitary, and pancreatic islets of humans and rodents. In the present study, we used immunoblotting to reveal the similarities between the expression patterns of SgIII in the common endocrine glands of chickens and rats. The protein–protein interactions between SgIII and chromogranin A (CgA) mediate the sorting of CgA/prohormone core aggregates to the secretory granule membrane. We examined these interactions using co-immunoprecipitation in chicken endocrine tissues. Using immunohistochemistry, we also examined the expression of SgIII in a wide range of chicken endocrine glands and gastrointestinal endocrine cells (GECs). SgIII was expressed in the pituitary, pineal, adrenal (medullary parts), parathyroid, and ultimobranchial glands, but not in the thyroid gland. It was also expressed in GECs of the stomach (proventriculus and gizzard), small and large intestines, and pancreatic islet cells. These SgIII-expressing cells co-expressed serotonin, somatostatin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, or insulin. These results suggest that SgIII is expressed in the endocrine cells that secrete peptide hormones, which mature via the intragranular enzymatic processing of prohormones and physiologically active amines in chickens. 相似文献
120.
Subhrojit SenShali Chen Biao FengYuexiu Wu Edmund LuiSubrata Chakrabarti 《Phytomedicine》2011,18(13):1110-1117