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991.
Leuconostoc mesenteroides strain NRRL B-1355 produces the soluble exopolysaccharides alternan and dextran in planktonic cultures. Mutants of this strain
are available that are deficient in the production of alternan, dextran, or both. Another mutant of NRRL B-1355, strain R1510,
produces an insoluble glucan in place of alternan and dextran. To test the effect of exopolysaccharide production on biofilm
formation, these strains were cultured in a biofilm reactor. All strains grew well as biofilms, with comparable cell densities,
including strain NRRL B-21414, which produces neither alternan nor dextran in planktonic cultures. However, the exopolysaccharide
phenotype clearly affected the appearance of the biofilms and the sloughed-off biofilm material produced by these biofilms.
For all strains, soluble glucansucrases and soluble polysaccharides produced by biofilm cultures appeared to be similar to
those produced by planktonic cultures. Biofilms from all strains also contained insoluble polysaccharides. Strain R1510 biofilms
contained an insoluble polysaccharide similar to that produced by planktonic cultures. For most other strains, the insoluble
biofilm polysaccharides resembled a mixture of alternan and dextran.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
992.
Dubsky P Hayden H Sachet M Bachleitner-Hofmann T Hassler M Pfragner R Gnant M Stift A Friedl J 《Cancer immunology, immunotherapy : CII》2008,57(6):859-870
BACKGROUND: Recent preclinical and clinical evidence suggests the use of allogeneic tumor as a source of antigen for DC-based immunotherapy against cancer. We hypothesized that addition of allogeneic tumor lysate to monocyte-derived DC culture could serve a dual purpose: (1) antigen source and (2) protein supplementation of DC culture media. Protein supplementation whether of known origin (human serum/plasma, fetal bovine serum, human serum albumin) or undeclared origin ("serum-free" media) is a source of variability and bias. We addressed the question whether protein supplementation can be omitted in the presence of allogeneic tumor lysate. MATERIALS AND METHODS: Human DC cultured in the presence of lysate from medullary thyroid carcinoma (MTC) cell line SHER-I (TuLy-DC) and DC pulsed with the same lysate but cultured in the presence of FBS (FBS-DC) were assessed for morphology, phenotype, maturation and functional properties. RESULTS: In comparison of FBS-DC/TuLy-DC no significant differences in morphology, phenotype and maturation could be detected. Both culture conditions produced CD1a(high), CD14(low) DC with high expression of costimulatory molecules and CD83 upon stimulation. TuLy-DC gave significantly better yields and produced more IL12p70. DC showed high (allo)stimulatory capacity toward T-cells. TuLy-DC induced more intracellular IFNgamma in CD8+T-cells of vaccinated MTC patients. Both types of DC induced killing of SHER-I after short in vitro restimulation. Tumor lysate from SHER-I can substitute for further protein supplementation in DC culture. Allogeneic tumor lysates should be taken into consideration as both source of antigen and protein supplementation in monocyte-derived DC culture. 相似文献
993.
994.
Kim MH Kim MO Heo JS Kim JS Han HJ 《Apoptosis : an international journal on programmed cell death》2008,13(2):295-304
This study examined the effect of acetylcholine (ACh) on the hypoxia-induced apoptosis of mouse embryonic stem (ES) cells.
Hypoxia (60 h) decreased both the cell viability and level of [3H] thymidine incorporation, which were prevented by a pretreatment with ACh. However, the atropine (ACh receptor [AChR] inhibitor)
treatment blocked the protective effect of ACh. Hypoxia (90 min) increased the intracellular level of reactive oxygen species
(ROS). On the other hand, ACh inhibited the hypoxia-induced increase in ROS, which was blocked by an atropine treatment. Subsequently,
the hypoxia-induced ROS increased the level of p38 mitogen activated protein kinase (MAPK) and Jun-N-terminal kinase (JNK)
phosphorylation, which were inhibited by the ACh pretreatment. Moreover, hypoxic exposure (90 min) increased the level of
nuclear factor-κB (NF-κB) phosphorylation, which was blocked by a pretreatment with SB 203580 (p38 MAPK inhibitor) or SP 600125
(JNK inhibitor). However, hypoxia (60 h) decreased the protein levels of Bcl-2 and c-IAPs (cellular inhibitor of apoptosis
proteins) but increased the level of caspase-3 activation. All these effects were inhibited by a pretreatment with ACh. In
conclusion, ACh prevented the hypoxia-induced apoptosis of mouse ES cells by inhibiting the ROS-mediated p38 MAPK and JNK
activation as well as the regulation of Bcl-2, c-IAPs, and caspase-3.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
995.
Because highly invasive species can rapidly assimilate rare taxa, we questioned whether two Florida endangered Lantana depressa varieties existed 21 years after Sanders documented their widespread hybridization with exotic Lantana strigocamara, and whether morphological traits could accurately discriminate genetic individuals. Stepwise discriminant analysis of morphological
characters discriminated the three taxa, correctly classifying 98, 91, 89% of L. strigocamara, L. depressa var. depressa, and var. floridana. Hybrids blurred taxonomic distinctions of varieties and reduced classification accuracy by 7–17%. Species-specific Random
Fragment Length Polymorphism (RFLP-PCR) confirmed hybridization has occurred. Intersimple Sequence Repeat (ISSR) fingerprints
analyzed with STRUCTURE identified three groups indicating introgression. Morphological traits significantly, but weakly correlated
with q ratios (P = 0.0001; r
2 = 0.45). Although L. strigocamara introgression is widespread and ongoing, wild populations contain individuals that are predominantly L. depressa genome, supporting actions to remove adventive L. strigocamara, prevent its sale, and promote sales of genetically confirmed natives. 相似文献
996.
997.
Rubinstein-Taybi syndrome (RSTS), a developmental disorder comprising abnormalities that include mental retardation, an unusual
facial appearance, broad thumbs and big toes is frequently associated with molecular lesions in the CREB-binding protein gene,
CREBBP. The objective of the present study was to identify and analyse CREBBP mutations in Indian RSTS patients on which there are no data. Direct sequencing of CREBBP performed in 13 RSTS patients identified the three zinc fingers (CH1, CH2, CH3) and HAT domain as mutational hotspots in
which ten novel pathogenic mutations were localized. Functional analysis revealed that three of these mutations affecting
amino acids Glu1459, Leu1668 and Glu1724 were critical for histone acetyltransferase activity. Twenty-eight novel CREBBP single-nucleotide polymorphisms (SNPs) were also identified in the Indian population. Linkage disequilibrium studies revealed
associations between (i) SNP (rs129974/c.3836-206G>C) and mutation (p.Asp1340Ala); (ii) (rs130002) with mutation (p.Asn435Lys) and (iii) SNPs rs129974, rs130002 and SNP (c.3836-206G>C) signifying a disease affection status. In conclusion, the present study reports the highest detection rate of CREBBP mutations (76.9%) in RSTS patients to date, of which ten are predicted to be pathogenic and three critical for histone acetyltransferase
activity. Moreover, identification of the association of CREBBP polymorphisms with disease susceptibility could be an important risk factor for the pathogenesis of RSTS. 相似文献
998.
Recently, the gene coding for a new beta-glucuronidase enzyme has been identified and cloned from Streptococcus equi subsp. zooepidemicus. This is another report of a beta-glucuronidase gene cloned from bacterial species. The ORF Finder analysis of a sequenced
DNA (EMBL, AJ890474) revealed a presence of 1,785 bp large ORF potentially coding for a 594 aa protein. Three protein families
in (Pfam) domains were identified using the Conserved Domain Database (CDD) analysis: Pfam 02836, glycosyl hydrolases family
2, triose phosphate isomerase (TIM) barrel domain; Pfam 02837, glycosyl hydrolases family 2, sugar binding domain; and Pfam
00703, glycosyl hydrolases family 2, immunoglobulin-like beta-sandwich domain. To gain more insight into the enzymatic activity,
the domains were used to generate a bootstrapped unrooted distance tree using ClustalX. The calculated distances for two domains,
TIM barrel domain, and sugar-binding domain were comparable and exhibited similarity pattern based on function and thus being
in accordance with recently published works confirming beta-glucuronidase activity of the enzyme. The calculated distances
and the tree arrangement in the case of centrally positioned immonoglobulin-like beta-sandwich domain were somewhat higher
when compared to other two domains but clustering with other beta-glucuronidases was rather clear. Nine proteins, including
beta-glucuronidases, beta-galactosidase, and mannosidase were selected for multiple alignment and subsequent distance tree
creation. 相似文献
999.
This article comprises a literature analysis of 41 river rehabilitation projects to assess the short-term (5 years) ability
of indicator groups to demonstrate progress towards river rehabilitation goals. Positive indications were compared to land-use,
river size, rehabilitation intervention and time. A questionnaire was developed to investigate river manager’s interpretation
of rehabilitation success and to assess their level of adherence to recommendations in the literature with regard to rehabilitation
assessment on a conceptual level. A total of 54 responses were received from respondents based in Germany, The Netherlands
and the United Kingdom. The results indicate that macroinvertebrate indicators, while widely used in assessing river rehabilitation
efforts, exhibited a lower frequency of positive responses than most other indicator types in the short term. Conversely,
terrestrial floodplain indicators exhibited the most frequent level of positive response for all ecological type indicators
leading to recommendations for further investigations into their use for short-term monitoring. Assessment procedures recommended
in literature are largely followed, illustrating the advances that have been made with regard to assessment planning. Indicator
responses are influenced by scale factors, for example, land-use and river size, that are often not considered by rehabilitation
managers. While an emphasis is placed on ecological, hydrological and morphological indicators in monitoring schemes, the
socioeconomic perspective (emphasized in the literature as forming an integral part of the river system) is neglected. 相似文献
1000.