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91.
STAT3 regulates the growth and immunoglobulin production of BCL(1) B cell lymphoma through control of cell cycle progression 总被引:3,自引:0,他引:3
Karras JG McKay RA Lu T Pych J Frank DA Rothstein TL Monia BP 《Cellular immunology》2000,202(2):124-135
STAT3 is constitutively phosphorylated on tyrosine(705) in self-renewing, CD5(+) murine B-1 lymphocytes. Nuclear extracts from untreated primary B-1 or CD5(+) BCL(1) B lymphoma cells were found to contain immunoreactive STAT3 protein that binds to a sis-inducible element present in the promoter of the p21(waf1/cip1) tumor suppressor gene and is constitutively phosphorylated on serine(727). To determine the functional significance of constitutive STAT3 activation in B lymphoma cells, a specific STAT3 antisense oligonucleotide was developed and used to examine basal BCL(1) cell growth and IgM production. Abrogating STAT3 expression in BCL(1) cells inhibited their proliferative capacity and induced a corresponding decrease in secretion of IgM. Cell cycle analysis showed a block in progression through G1 in BCL(1) cells treated with the STAT3 antisense oligonucleotide. These results indicate that STAT3 controls cell growth and immunoglobulin secretion by enhancing progression through the G1 phase of the cell cycle in BCL(1) B cell lymphoma. 相似文献
92.
Conspicuous differences in floral morphology are partly responsible for reproductive isolation between two sympatric species of monkeyflower because of their effect on visitation of the flowers by different pollinators. Mimulus lewisii flowers are visited primarily by bumblebees, whereas M. cardinalis flowers are visited mostly by hummingbirds. The genetic control of 12 morphological differences between the flowers of M. lewisii and M. cardinalis was explored in a large linkage mapping population of F2 plants n = 465 to provide an accurate estimate of the number and magnitude of effect of quantitative trait loci (QTLs) governing each character. Between one and six QTLs were identified for each trait. Most (9/12) traits appear to be controlled in part by at least one major QTL explaining >/=25% of the total phenotypic variance. This implies that either single genes of individually large effect or linked clusters of genes with a large cumulative effect can play a role in the evolution of reproductive isolation and speciation. 相似文献
93.
Neumer John F. Gordon Michael D. McEwen Charles N. Peacock Patricia M. Hill Steven A. McKay Richard G. Lazar Joseph Valentine James R. Van Lenten Frank J. Foris Aanthony 《Origins of life and evolution of the biosphere》1998,28(1):27-45
Molecular orbital spectral predictions suggest that 2,5,7,10,12,15,17,20-octaaza-21H, 23H-porphine has a visible spectral range closely matching that of chlorophyll-a. Since the octaazaporphine is, in its core, a simple derivative of an (HCN)12 oligomer, this fact, together with its spectral properties, would suggest that it occupies a high rank as a primordial porphinic solar energy transducer for photochemistry essential to life's formation. The demonstration that the mass 324 hexahydrooctaazaporphine is formed in protic media by the cyclotetramerization of imidazol-4-aminohydroxonium ion or the derived nitrenium ion, and that a mass 318 species consonant with that of the Hückel aromatic octaazaporphine is observed in the course of these studies, strongly supports the proposed octaazaporphine synthesis in a prebiotic hydrocyanic acid milieu. 相似文献
94.
Aqueous solutions of highly esterified propylene glycol alginate and gelatin interact rapidly in mildly alkaline conditions to form a gel with a very high melting point. The interaction involves the formation of amide bonds between the ester and uncharged amino groups on the protein.Neither high-methoxyl pectin nor highly esterified propylene glycol pectate formed thermostable gels with gelatin, and the lack of reactivity was not due to differences between pectate and alginate in viscosity, rate of depolymerisation or rate of saponification. Pectate esters will react, however, with low molecular weight diamines in anhydrous conditions.It is suggested that the different reactivity of the uronides in water reflects differences in the geometries of their glycosidic links between monomers, and that in alginate it is the mannuronic residues that are involved in these reactions. 相似文献
95.
96.
T.J. Fiedler A. Hudder S.J. McKay S. Shivkumar T.R. Capo M.C. Schmale P.J. Walsh 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2010,5(2):165-170
Aplysia californica is a marine opisthobranch mollusc used as a model organism in neurobiology for cellular analyses of learning and behavior because it possesses a comparatively small number of neurons of large size. The mollusca comprise the second largest animal phylum, yet detailed genetic and genomic information is only recently beginning to accrue. Thus developmental and comparative evolutionary biology as well as biomedical research would benefit from additional information on DNA sequences of Aplysia. Therefore, we have constructed a series of unidirectional cDNA libraries from different life stages of Aplysia. These include whole organisms from the egg, veliger, metamorphic, and juvenile stages as well as adult neural tissue for reference. Individual clones were randomly picked, and high-throughput, single pass sequence analysis was performed to generate 7971 sequences. Of these, there were 5507 quality-filtered ESTs that clustered into 1988 unigenes, which are annotated and deposited into GenBank. A significant number (497) of ESTs did not match existing Aplysia ESTs and are thus potentially novel sequences for Aplysia. GO and KEGG analyses of these novel sequences indicated that a large number were involved in protein binding and translation, consistent with the predominant biosynthetic role in development and the presence of stage-specific protein isoforms. 相似文献
97.
M. Settles R. Zanella S. D. McKay R. D. Schnabel J. F. Taylor R. Whitlock Y. Schukken J. S. Van Kessel J. M. Smith H. Neibergs 《Animal genetics》2009,40(5):655-662
The purpose of this study was to identify loci associated with Mycobacterium avium subspecies paratuberculosis ( Map ) infection status in US Holsteins using the Illumina BovineSNP50 BeadChip whole genome single nucleotide polymorphism (SNP) assay. Two hundred forty-five cows from dairies in New York, Pennsylvania and Vermont enrolled in longitudinal herd studies between January 1999 and November 2007 were assessed for the presence of Map in both faecal and tissue samples. An animal was considered tissue infected if any sample contained at least one colony forming unit of Map per gram of tissue (CFU/g) and the same definition was employed for faecal samples. Each animal was genotyped with the Illumina BovineSNP50 BeadChip and after quality assurance filtering, 218 animals and 45 683 SNPs remained. We sought to identify loci associated with four different case/control classifications: presence of Map in the tissue, presence of Map in faeces, presence of Map in both tissue and faeces and presence of Map in tissue but not faeces. A case–control genome wide association study was conducted to test the four different classifications of Map infection status (cases) when compared with a Map -negative control group (control). Regions on chromosomes 1, 5, 7, 8, 16, 21 and 23 were identified with moderate significance ( P < 5 × 10−5 ). Two regions, one on chromosome 3 (near EDN2 ) and another on chromosome 9 (no positional gene candidates), were identified with a high level of association to the presence of Map in tissue and both tissue and faeces respectively ( P < 5 × 10−7 , genome-wide Bonferonni P < 0.05). 相似文献
98.
99.
Metabolic syndrome is common and persistent in youth‐onset type 2 diabetes: Results from the TODAY clinical trial 下载免费PDF全文
100.
Error management theory is a theory of considerable scope and emerging influence. The theory claims that cognitive biases do not necessarily reflect flaws in evolutionary design, but that they may be best conceived as design features. Unfortunately, existing accounts are vague with respect to the key concept of bias. The result is that it is unclear that the cognitive biases that the theory seeks to defend are not simply a form of behavioral bias, in which case the theory reduces to a version of expected utility theory. We propose some clarifications and refinements of error management theory by emphasizing important distinctions between different forms of behavioral and cognitive bias. We also highlight a key assumption, that the capacity for Bayesian beliefs is subject to constraints. This assumption is necessary for what we see as error management theory's genuinely novel claim: that behavioral tendencies to avoid costly errors can rest on systematic departures from Bayesian beliefs and that the latter can be adaptive insofar as they generate the former. 相似文献