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61.
Sashio H Tamura K Ito R Yamamoto Y Bamba H Kosaka T Fukui S Sawada K Fukuda Y Tamura K Satomi M Shimoyama T Furuyama J 《Immunogenetics》2002,53(12):1020-1027
The importance of tumor necrosis factor (TNF)-alpha and the TNF receptor gene polymorphisms in the etipathogenesis of inflammatory bowel disease (IBD) has not been elucidated. DNA from peripheral blood samples was obtained from 124 patients with Crohn's disease (CD), 106 patients with ulcerative colitis (UC), and 111 unrelated healthy controls. We examined two single nucleotide polymorphisms (SNPs) of the TNF-alpha gene, TNF (-308 G/A and -238 G/A), an SNP of the TNF receptor superfamily member 1A gene, TNFRSF1A(also known as TNFR1), at codon 12 in exon 1 (CCA/CCG), and two SNPs of the 1B gene, TNFRSF1B (also known as TNFR2), (1466 A/G and 1493 C/T). There was a difference in the carrier frequency for haplotype AG (-308 A, -238 G) between UC patients and the controls (OR=4.76, 95% CI=1.53-14.74, P<0.01). We found a significant difference in carrier frequency for haplotype AT (1466 A, 1493 T) of the TNFRSF1B gene between CD patients and the controls (OR=2.13, 95% CI=1.08-4.21, P<0.05). The significance proved to be greater in CD patients with both internal and external fistula (OR=4.8, 95% CI=1.73-13.33, P<0.01), and in those who were poor responders ( n=22) to our treatments, which consisted of nutritional therapy, medical therapy and surgical therapy (OR=9.24, 95% CI=3.37-25.36, P<0.001). This study suggests that one of the genes responsible for UC may be the TNF gene, or an adjacent gene, and that TNFRSF1B gene polymorphisms contribute greatly to the increased onset risk of CD and to the disease behavior. 相似文献
62.
Involvement of FKHR-dependent TRADD expression in chemotherapeutic drug-induced apoptosis 总被引:5,自引:0,他引:5 下载免费PDF全文
Rokudai S Fujita N Kitahara O Nakamura Y Tsuruo T 《Molecular and cellular biology》2002,22(24):8695-8708
63.
Shikazono N Tanaka A Kitayama S Watanabe H Tano S 《Radiation and environmental biophysics》2002,41(2):159-162
To clarify the effect of heavy ions in plants, dry seeds of Arabidopsis were irradiated with carbon, neon, and argon ions with various linear energy transfer (LET) values. The relative biological effectiveness (RBE) for lethality peaked at LET values over 350 keV/microns for neon and argon ions. This LET giving the peak RBE was higher than the LET of 100-200 keV/microns which was reported to have a maximum RBE for other types of cells, such as mammalian cells. Furthermore, sterility showed a higher RBE at an LET of 354 keV/microns with neon ions than that at an LET of 113 keV/microns with carbon ions. Lethality and sterility are both considered to be caused by damage to DNA. The results indicate that the LET having a maximum of RBE for lethality is higher in Arabidopsis seeds than in other unicellular systems. The most likely explanation for this shift of LET is that the DNA in dry seeds has a different chemical environment and/or hydration state than the DNA in cells in culture. 相似文献
64.
Sakurai H Nishi A Sato N Mizukami J Miyoshi H Sugita T 《Biochemical and biophysical research communications》2002,297(5):1277-1281
TAK1 mitogen-activated protein kinase kinase kinase (MAP3K) is activated by its specific activator, TAK1-binding protein 1 (TAB1). A constitutively active TAK1 mutant has not yet been generated due to the indispensable requirement of TAB1 for TAK1 kinase activity. In this study, we generated a novel constitutively active TAK1 by fusing its kinase domain to the minimal TAK1-activation domain of TAB1. Co-immunoprecipitation assay demonstrated that these domains interacted intra-molecularly. The TAK1-TAB1 fusion protein showed a significant MAP3K activity in vitro and activated c-Jun N-terminal kinase/p38 MAPKs and IkappaB kinase in vivo, which was followed by increased production of interleukin-6. These results indicate that the fusion protein is useful for characterizing the physiological roles of the TAK1-TAB1 complex. 相似文献
65.
66.
Determination of polycyclic aromatic hydrocarbons in milk samples by high-performance liquid chromatography with fluorescence detection 总被引:1,自引:0,他引:1
Kishikawa N Wada M Kuroda N Akiyama S Nakashima K 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,789(2):257-264
This paper describes a high-performance liquid chromatographic (HPLC) method for the determination of polycyclic aromatic hydrocarbons (PAHs) in milk samples. The method involves a liquid-liquid extraction procedure after saponification of milk samples with sodium hydroxide. Reproducible determination with highly sensitive detection was attained by HPLC with fluorescence detection using 1,2-bis(9-anthryl)ethane as an internal standard. The detection limits of 12 kinds of PAHs ranged from 1.3 to 76 ng/kg milk at a signal/noise ratio of 3. By the proposed method, the presence of 12 and 11 kinds of PAHs could be confirmed in commercial milk and human milk samples, respectively. The average concentrations of total PAHs (mean+/-SD, micro g/kg) were found to be 0.99+/-0.37 for commercial milk (n=14), 2.01+/-0.30 for infant formula (n=3) and 0.75+/-0.47 for human milk (n=51). High correlation coefficients between the concentrations of total PAHs and triglyceride were observed for commercial milk (r=0.659) and human milk (r=0.645). 相似文献
67.
Basal euteleostean relationships: a mitogenomic perspective on the phylogenetic reality of the "Protacanthopterygii" 总被引:9,自引:0,他引:9
Higher-level relationships of the basal Euteleostei (=Protacanthopterygii) are so complex and controversial that at least nine different morphology-based phylogenetic hypotheses have been proposed during the last 30 years. Relationships of the Protacanthopterygii were investigated using mitochondrial genomic (mitogenomic) data from 34 purposefully chosen species (data for 12 species being newly determined during the study) that fully represented major basal euteleostean lineages and some basal teleosts plus neoteleosts as outgroups. Unweighted and weighted maximum parsimony (MP) and maximum likelihood (ML) analyses were conducted with the data set that comprised concatenated nucleotide sequences from 12 protein-coding genes (excluding the ND6 gene and 3rd codon positions) and 22 transfer RNA (tRNA) genes (stem regions only) from the 34 species. The resultant trees were well resolved and largely congruent, with most internal branches being supported by high statistical values. Monophyly of the protacanthopterygians was confidently rejected by the mitogenomic data. Of the five major monophyletic groups that received high statistical support within the protacanthopterygians, a clade comprising members of the alepocephaloids was unexpectedly nested within the Otocephala, sister-group of the euteleosts. The remaining four major monophyletic groups, on the other hand, occupied phylogenetic positions intermediate between the otocephalans and neoteleosts, with a clade comprising esociforms + salmoniforms being more basal to the argentinoids and osmeroids. Although interrelationships of the latter two clades (argentinoids and osmeroids) with the neoteleosts remained ambiguous, the present results indicated explicitly that the protacanthopterygians as currently defined merely represent a collective, polyphyletic group of the basal euteleosts, located between the basal teleosts (elopomorphs and below) and neoteleosts (stomiiforms and above). 相似文献
68.
A homeobox gene, HB9, has been isolated from the tarsometatarsal skin of 13-day-old chick embryos using a degenerate RT-PCR-based screening method. In situ hybridization analysis revealed that, during development of chick embryonic skin, the HB9 gene was expressed in epidermal basal cells of the placodes, but not in those of interplacodes, and in the dermal cells under the placodes at 9 days before addition of an intermediate layer by proliferation of the basal cells in the placodes. With the onset of epidermal stratification, the direction of the basal cell mitosis changed, with the axis becoming vertical to the epidermal surface. Placodes and interplacodes form outer and inner scales, respectively, after they have elongated distally (Tanaka S, Kato Y (1983b) J Exp Zool
225: 271–283). During scale ridge elongation at 12–15 days, HB9 was strongly expressed in the epidermis of the outer scale face, where the cell proliferation is more active than in the epidermis of the inner scale face; hence, stratification of the outer scale face is more prominent than that of the inner scale face. After 16 days, when mitotic activity in the epidermal basal cells decreases and the thickness of the epidermis is maintained at a constant level, the HB9 expression decreases with the onset of epidermal keratinization. These results suggest that HB9 may be involved in the proliferation of the epidermal basal cells that accompanies epidermal stratification. 相似文献
69.
Eguchi A Kondoh T Kosaka H Suzuki T Momota H Masago A Yoshida T Taira H Ishii-Watabe A Okabe J Hu J Miura N Ueda S Suzuki Y Taki T Hayakawa T Nakanishi M 《The Journal of biological chemistry》2000,275(23):17549-17555
In the early stage of infection, Sendai virus delivers its genome into the cytoplasm by fusing the viral envelope with the cell membrane. Although the adsorption of virus particles to cell surface receptors has been characterized in detail, the ensuing complex process that leads to the fusion between the lipid bilayers remains mostly obscure. In the present study, we identified and characterized cell lines with a defect in the Sendai virus-mediated membrane fusion, using fusion-mediated delivery of fragment A of diphtheria toxin as an index. These cells, persistently infected with the temperature-sensitive variant Sendai virus, had primary viral receptors indistinguishable in number and affinity from those of parental susceptible cells. However, they proved to be thoroughly defective in the Sendai virus-mediated membrane fusion. We also found that viral HN protein expressed in the defective cells was responsible for the interference with membrane fusion. These results suggested the presence of a previously uncharacterized, HN-dependent intermediate stage in the Sendai virus-mediated membrane fusion. 相似文献
70.
Koizumi M Akahori K Ohmine T Tsutsumi S Sone J Kosaka T Kaneko M Kimura S Shimada K 《Bioorganic & medicinal chemistry letters》2000,10(19):2213-2216
2'-Deoxyguanosine residues of a 3',5'-end-modified hexadeoxyribonucleotide (R-95288) with anti-HIV-1 activity were substituted with N2-methyl-2'-deoxyguanosine (m2dG). These modified oligodeoxyribonucleotides (ODNs) showed a 2-fold higher activity than R-95288. Also, the CD spectra of these ODNs indicated that the m2dG modification stabilized the tertiary structure of the G-quadruplex. 相似文献