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1.
Three Approaches to the Study of Language and Gender 总被引:1,自引:0,他引:1
Bonnie McElhinny 《American anthropologist》2003,105(4):848-852
Gender across Languages: The Linguistic Representation of Women and Men. Vol. 2. Marlis Hellinger and Hadumod Bußmann eds. Amsterdam: John Benjamins, 2002. 348 pp.
Gender Identity and Discourse Analysis. Lia Litosseliti and Jane Sunderland eds. Amsterdam: John Benjamins, 2002. 335 pp.
Talking Gender and Sexuality. Paul McIlvenny. ed. Amsterdam: John Benjamins, 2002. 327 pp. 相似文献
Gender Identity and Discourse Analysis. Lia Litosseliti and Jane Sunderland eds. Amsterdam: John Benjamins, 2002. 335 pp.
Talking Gender and Sexuality. Paul McIlvenny. ed. Amsterdam: John Benjamins, 2002. 327 pp. 相似文献
2.
Melinda Bonnie Fagan 《Biology & philosophy》2012,27(2):179-213
Stem cell biology and systems biology are two prominent new approaches to studying cell development. In stem cell biology,
the predominant method is experimental manipulation of concrete cells and tissues. Systems biology, in contrast, emphasizes
mathematical modeling of cellular systems. For scientists and philosophers interested in development, an important question
arises: how should the two approaches relate? This essay proposes an answer, using the model of Waddington’s landscape to
triangulate between stem cell and systems approaches. This simple abstract model represents development as an undulating surface
of hills and valleys. Originally constructed by C. H. Waddington to visually explicate an integrated theory of genetics, development
and evolution, the landscape model can play an updated unificatory role. I examine this model’s structure, representational
assumptions, and uses in all three contexts, and argue that explanations of cell development require both mathematical models
and concrete experiments. On this view, the two approaches are interdependent, with mathematical models playing a crucial
but circumscribed role in explanations of cell development. 相似文献
3.
Human λ light chain locus: Organization and DNA sequences of three genomicJ regions 总被引:14,自引:0,他引:14
Evidence for the genomic organization of human lambda light chain joining (J) region gene segments is presented. A mouse J probe was used in Southern hybridizations to localize joining region sequences in a cosmid clone containing the genomic cluster of six human lambda constant (C) region gene segments. The results of these hybridizations suggest the presence of at least one J gene segment upstream from each constant region gene segment. The DNA sequences indicate that the human JI, J2, and J3 gene segments have consensus nonamer and heptamer sequences, proposed to be involved in V-J joining, are capable of encoding the known amino acid sequences for the respective J peptides, and have a sequence which could give functional RNA splice site at the end of their coding regions. Our data show that a single functional J is located 1.3 or 1.6 kb upstream of each of the C gene segments known to encode the Mcg, Kern– Oz–, and Kern–Oz+ isotypes. Therefore, the gene organization of this region of the human lambda locus is J1 CI -J2C2-J3C3. The DNA sequences ofJ
1,J
2, andJ
3 presented in this paper establish that a singleJ
gene segment precedes each expressed C gene segment, and support a model for the evolution of the human JC clusters where JICI andJ2C2-J3C3. arose from different ancestral JC units. 相似文献
4.
The response of a bumblebee goby,Brachygobius sabanus,to chemical stimuli from injured conspecifics 总被引:1,自引:0,他引:1
Synopsis
Brachygobius sabanus move less often and spend less time swimming when they detect chemicals released from injured conspecifics. This resembles the alarm response found in ostariophysan fishes, darters, and at least one other gobiid. Chemicals from injured Poecilia reticulata do not induce an alarm response in B. sabanus. 相似文献
5.
Patsy M. Brannon Bonnie M. Orrison Norman Kretchmer 《In vitro cellular & developmental biology. Plant》1985,21(1):6-14
Summary Rat pancreatic acinar cells were isolated and cultured in Ham's F12 medium with 15% bovine calf serum. Caerulein, insulin,
somatostatin, and dexamethasone (DEX) had no effect on intracellular or secreted amylase in these cultured cells. A serum-free
medium, using Waymouth's MB 752/1 supplemented with albumin, epidermal growth factor (EGF), DEX, and HEPES, was then developed
to avoid serum factors that might mask hormonal effects. In this SF medium, pancreatic acinar, cells maintained the morphological
and ultrastructural characteristics of freshly isolated cells and secreted amylase in response to the secretagogue, carbamyl
choline. Insulin, at a concentration of 1 μg/ml, significantly increased intracellular and secreted amylase activity after
3 d. This model cell system can be used to study the regulation of the synthesis of amylase and other pancreatic enzymes in
vitro. 相似文献
6.
Bonnie J. Reger Maurice S.B. Ku Jeffrey W. Pottert John J. Evans 《Phytochemistry》1983,22(5):1127-1132
The ribulose-1,5-bisphosphate carboxylase/oxygenase purified from maize (a C4 monocot) to homogeneity has a MW of532 000 and sedimentation coeffici 相似文献
7.
Alcohol dehydrogenase thermostability variants in Drosophila melanogaster: Comparison of activity ratios and enzyme levels 总被引:2,自引:0,他引:2
Representatives of five allozymic classes of Drosophila alcohol dehydrogenase have been compared with respect to their activity levels on two alcohol substrates, quantities of ADH protein, and stability in crude extracts. Within each allozymic class, strains from widely diverse geographic locations differ in their enzyme activity levels but are identical for a measure known as "activity ratio," which is obtained by dividing the average activity reading on isopropanol by that obtained with ethanol. They are also similar in the rate at which ADH activity declines in crude extracts held at 25 degrees C. For several of the fast-resistant and fast-moderate strains, differences in ADH activity are associated with differences in the amount of enzyme present. The catalytic efficiencies of the fast-resistant forms are considerably lower than those of the fast-moderate allozymes. The origin and persistence of the rare but ubiquitous fast-resistant allozyme is discussed. 相似文献
8.
Transport of Biosynthetic Intermediates: Regulation of Homoserine and Threonine Uptake in Escherichia coli 总被引:8,自引:6,他引:2 下载免费PDF全文
Homoserine is transported by a single system that it shares with alanine, isoleucine, leucine, phenylalanine, threonine, valine and perhaps cysteine, methionine, serine, and tyrosine. We investigated the regulation of this transport system and found that alanine, isoleucine, leucine, methionine, and valine each repress the homoserine-transporting system. From the concentration resulting in 50% repression of this transport system and the maximal amount of repression, we ranked the amino acids according to their effectiveness in repressing homoserine transport (in decreasing order): leucine>methionine>alanine>valine>isoleucine. The exponential rate of decrease in transport capacity after leucine addition equals the exponential growth rate of the culture, and protein synthesis is necessary for the derepression seen when leucine is removed. Threonine, in addition to using the above system, is transported by a second system shared with serine. We present further evidence for this serine-threonine transport system and show that it is not regulated like the homoserine-transporting system. 相似文献
9.
Substrate Effect on 2,3-Butylene Glycol Production by Rhizopus nigricans and Penicillium expansum 总被引:1,自引:1,他引:0 下载免费PDF全文
Rhizopus nigricans and Penicillium expansum produced 2,3-butylene glycol which accumulated in natural and artificial media with time. Mycelial mats of P. expansum decreased the quantity of a diacetyl substrate and converted part of this substrate into acetylmethylcarbinol (AMC) and 2,3-butylene glycol. Mycelial mats of P. expansum also decreased AMC substrate with the formation of 2,3-butylene glycol. 2,3-Butylene glycol decreased slightly during incubation with the fungal mat. The formation of AMC was suppressed significantly by cysteine and ascorbic acid. 相似文献
10.
Clare M. O'Connor Bonnie J. Germain Kathleen M. Guthrie Dana W. Aswad Clarke F. Millette 《Molecular reproduction and development》1989,22(3):307-319
An antiserum prepared against the purified protein carboxyl methltransferase (PCMT) from bovine brain has been used to compare testicular and ovarian levels of the enzyme and to study the regulation of PCMT concentrations during spermatogenesis. The PCMT, which specifically modifies age-damaged aspartyl residues, is present at a significantly higher concentration in mature mouse testis than in ovary. However, the PCMT is present at nearly equal concentrations in extracts of germ cell-deficient ovaries and testes obtained from mutant atrichosislatrichosis mice. In normal testis, the concentration of the PCMT increases severalfold during the first 4–5 weeks after birth, paralleling the appearance and maturation of testicular germ cells. Both immunochemical and enzymatic measurements of PCMT specific activities in purified spermatogenic cell preparations indicate that PCMT levels are twofold and 3.5-fold higher in round spermatids and residual bodies, respectively, than in pachytene spermatocytes. The results are consistent with the enhanced synthesis and/or stability of the PCMT in spermatogenic cells and with the continued translation of the PCMT during the haploid portion of spermatogenesis. The relatively high levels of PCMT in spermatogenic cells may be important for the extensive metabolism of proteins accompanying spermatid condensation or for the repair of damaged proteins in translationally inactive spermatozoa. 相似文献