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121.
122.
TLRs detect several classes of virus-associated molecules, such as ssRNA, CpG-DNA and dsRNA, and transduce signals leading to the production of IFN. Recently discovered cytoplasmic RNA helicases, RIG-I and MDA5, selectively sense viral RNA species. Gene disruption studies revealed the critical but non-redundant function of RIG-I and MDA5 in host antiviral responses. 相似文献
123.
Unlike humans, which are the sole remaining representatives of a once larger group of bipedal apes (hominins), the “lesser
apes” (hylobatids) are a diverse radiation with numerous extant species. Consequently, the lesser apes can provide a valuable
evolutionary window onto the possible interactions (e.g., interbreeding) of hominin lineages coexisting in the same time and
place. In the present work, we employ chromosomal analyses to verify the hybrid ancestry of an individual (Larcon) produced
by two of the most distant genera of lesser apes, Hylobates (lar-group gibbons) and Nomascus (concolor-group gibbons). In addition to a mixed pelage pattern, the hybrid animal carries a 48-chromosome karyotype that consists
of the haploid complements of each parental species: Hylobates lar (n = 22) and Nomascus leucogenys leucogenys (n = 26). Studies of this animal’s karyotype shed light onto the processes of speciation and genus-level divergence in the lesser
apes and, by extension, across the Hominoidea. 相似文献
124.
Identification of a free radical is performed for the reaction mixture of rat brain homogenate with a ferrous ion/ascorbic acid system using EPR, high performance liquid chromatography-electron paramagnetic resonance spectrometry (HPLC-EPR) and high performance liquid chromatography-electron paramagnetic resonance-mass spectrometry (HPLC-EPR-MS). EPR measurements of the reaction mixtures showed prominent signals with hyperfine coupling constants (alpha(N) = 1.58 mT and alpha(H)beta = 0.26 mT). No EPR spectrum was detectable without rat brain homogenate, suggesting that the radical is derived from rat brain homogenate. An HPLC-EPR analysis of the reaction mixture showed a peak with retention time of 33.7 min. An HPLC-EPR-MS analysis of the peak gave two ions at m/z 224 and 137, suggesting that alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN)/ethyl radical adduct forms in the reaction mixture. 相似文献
125.
RNA interference (RNAi) has been used to suppress gene expression in various eukaryotic organisms. In plants, RNAi can be
induced by introduction of an RNAi vector that transcribes a self-complementary hairpin RNA. Most basic RNAi constructs have
an inverted repeat interrupted with a spacer sequence. To test silencing capability of RNAi constructs, we developed an in
vivo assay that is based on the RNAi-mediated changes of the α-linolenic acid content in hairy roots. A tobacco endoplasmic
reticulum ω-3 fatty acid desaturase (NtFAD3) is the main enzyme for production of α-linolenic acid of root membrane lipids.
Tobacco hairy roots transformed with the RNAi vectors against the NtFAD3 gene showed a decrease in α-linolenic acid content. The frequency of RNA silencing was more affected by spacer sequence than
by spacer length, at least between 100 and 1800 bp. Since significant amounts of hairpin RNA against the NtFAD3 gene remained in the transgenic plants displaying a weak silencing phenotype, low degree of silencing was attributed to low
efficiency of hairpin RNA processing mediated by Dicer-like proteins. Our results show the possibility of producing a broad
range of the RNAi-induced silencing phenotypes by replacing the spacer sequence of RNAi construct. 相似文献
126.
The mesoderm-derived segmental somite differentiates into dermomyotome and sclerotome, the latter of which undergoes vertebrogenesis
to spinal cartilage and ultimately to vertebral bones. However, analysis and manipulation of the developing mammalian vertebrae
in the same embryo has been infeasible because of their placental-dependent embryogenesis. Here, we report a novel culture
system of the mouse embryonic tailbud, by which the developmental processes of mammalian vertebral cartilage are traceable
and manipulatable in the same sample. The anaplastic segmental somites/sclerotomes in the tailbud of 13 gestational day (g.d.)
embryo that are structurally continuous to the vertebral column underwent progressive vertebrogenesis when (1) the ectoderm-derived
nascent epidermis was microsurgically removed prior to cultivation, and (2) the sample was incubated at the air-medium interface.
After cultivation for 5 days, the size and shape of the instructed vertebral cartilage showed features comparable to well-differentiated
body vertebra along with the expression of the cartilage marker collagen type II, suggesting that aggressive differentiation
of the sclerotomal cell lineage was achieved. In the presence of recombinant bone morphogenic protein (BMP) and Noggin, or
adenoviral particles for extracellular epimorphin, dramatic alteration of the vertebral morphology ensued in the explants.
Thus, this model system provides an approach to study the detailed molecular mechanisms of mammalian vertebrogenesis and enables
pretreatment strategies of precartilagious fragments for improving the efficacy of subsequent transplantation. 相似文献
127.
Fujimoto T Kunitomo J Tomata Y Nishiyama K Nakashima M Hirozane M Yoshikubo S Hirai K Marui S 《Bioorganic & medicinal chemistry letters》2011,21(21):6414-6416
During our efforts to identify a series of potent, selective, orally active human Orexin-2 Receptor (OX2R) antagonists, we elucidated structure-activity relationship (SAR) on the 7-position of a benzoxazepine scaffold by utilizing Hammett σ(p) and Hansch-Fujita π value as aromatic substituent constants. The attempts led to the discovery of compound 1m, possessing good in vitro potency with over 100-fold selectivity against OX1R, good metabolic stability in human and rat liver microsome, good oral bioavailability in rats, and in vivo antagonistic activity in rats by oral administration. 相似文献
128.
Okazaki M Nimitkeatkai H Muramatsu T Aoyama H Ueno K Mizutani M Hirai N Kondo S Ohnishi T Todoroki Y 《Bioorganic & medicinal chemistry》2011,19(1):406-413
We developed abscinazole-E1 (Abz-E1), a specific inhibitor of abscisic acid (ABA) 8′-hydroxylase (CYP707A). This inhibitor was designed and synthesized as an enlarged analogue of uniconazole (UNI), a well-known plant growth retardant, which inhibits a gibberellin biosynthetic enzyme (ent-kaurene oxidase, CYP701A) as well as CYP707A. Our results showed that Abz-E1 functions as a potent inhibitor of CYP707A and a poor inhibitor of CYP701A both in vitro and in vivo. Abz-E1 application to plants resulted in improved desiccation tolerance and an increase in endogenous ABA. 相似文献
129.
Kazuhisa Kato Shinichi Maruyama Tadayoshi Hirai Kyoko Hiwasa-Tanase Tsuyoshi Mizoguchi Eiji Goto Hiroshi Ezura 《Plant signaling & behavior》2011,6(8):1172-1179
One of the ultimate goals of plant science is to test a hypothesis obtained by basic science and to apply it to agriculture and industry. A plant factory is one of the ideal systems for this trial. Environmental factors affect both plant yield and the accumulation of recombinant proteins for industrial applications within transgenic plants. However, there have been few reports studying plant productivity for recombinant protein in closed cultivation systems called plant factories.To investigate the effects of photosynthetic photon flux (PPF) on tomato fruit yield and the accumulation of recombinant miraculin, a taste-modifying glycoprotein, in transgenic tomato fruits, plants were cultivated at various PPFs from 100 to 400 (µmol m−2 s−1) in a plant factory. Miraculin production per unit of energy used was highest at PPF100, although miraculin production per unit area was highest at PPF300. The commercial productivity of recombinant miraculin in transgenic tomato fruits largely depended on light conditions in the plant factory. Our trial will be useful to consider the trade-offs between the profits from production of high-value materials in plants and the costs of electricity.Key words: light, molecular farming, recombinant miraculin, taste-modifying protein, transgenic tomato 相似文献
130.