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81.
Steindler L Schuster S Ilan M Avni A Cerrano C Beer S 《Marine biotechnology (New York, N.Y.)》2007,9(5):543-549
The molecular mechanisms involved in the establishment and maintenance of sponge photosymbiosis, and in particular the association
with cyanobacteria, are unknown. In the present study we analyzed gene expression in a common Mediterranean sponge (Petrosia ficiformis) in relation to its symbiotic (with cyanobacteria) or aposymbiotic status. A screening approach was applied to identify genes
expressed differentially in symbiotic specimens growing in the light and aposymbiotic specimens growing in a dark cave at
a short distance from the illuminated specimens. Out of the various differentially expressed sequences, we isolated two novel
genes (here named PfSym1 and PfSym2) that were up-regulated when cyanobacterial symbionts were harbored inside the sponge cells. The sequence of one of these
genes (PfSym2) was found to contain a conserved domain: the scavenger receptor cysteine rich (SRCR) domain. This is the first report on
the expression of sponge genes in relation to symbiosis and, according to the presence of an SRCR domain, we suggest possible
functions for one of the genes found in the sponge-cyanobacteria symbiosis. 相似文献
82.
Bainbridge J Madden L Essex D Binks M Malhotra R Paleolog EM 《Arthritis research & therapy》2007,9(6):R127
The enzyme methionine aminopeptidase-2 (MetAP-2) is thought to play an important function in human endothelial cell proliferation,
and as such provides a valuable target in both inflammation and cancer. Rheumatoid arthritis (RA) is a chronic inflammatory
disease associated with increased synovial vascularity, and hence is a potential therapeutic target for angiogenesis inhibitors.
We examined the use of PPI-2458, a selective non-reversible inhibitor of MetAP-2, in disease models of RA, namely acute and
chronic collagen-induced arthritis (CIA) in mice. Whilst acute CIA is a monophasic disease, CIA induced with murine collagen
type II manifests as a chronic relapsing arthritis and mimics more closely the disease course of RA. Our study showed PPI-2458
was able to reduce clinical signs of arthritis in both acute and chronic CIA models. This reduction in arthritis was paralleled
by decreased joint inflammation and destruction. Detailed mechanism of action studies demonstrated that PPI-2458 inhibited
human endothelial cell proliferation and angiogenesis in vitro, without affecting production of inflammatory cytokines. Furthermore, we also investigated release of inflammatory cytokines
and chemokines from human RA synovial cell cultures, and observed no effect of PPI-2458 on spontaneous expression of cytokines
and chemokines, or indeed on the angiogenic molecule vascular endothelial growth factor (VEGF). These results highlight MetAP-2
as a good candidate for therapeutic intervention in RA. 相似文献
83.
84.
Emma Tham Anna Lindstrand Avni Santani Helena Malmgren Addie Nesbitt Holly?A. Dubbs Elaine?H. Zackai Michael?J. Parker Francisca Millan Kenneth Rosenbaum Golder?N. Wilson Ann Nordgren 《American journal of human genetics》2015,96(3):507-513
Through a multi-center collaboration study, we here report six individuals from five unrelated families, with mutations in KAT6A/MOZ detected by whole-exome sequencing. All five different de novo heterozygous truncating mutations were located in the C-terminal transactivation domain of KAT6A: : c.3116_3117 delCT, p.(Ser1039∗); c.3830_3831insTT, p.(Arg1278Serfs∗17); c.3879 dupA, p.(Glu1294Argfs∗19); c.4108G>T p.(Glu1370∗) and c.4292 dupT, p.(Leu1431Phefs∗8). An additional subject with a 0.23 MB microdeletion including the entire KAT6A reading frame was identified with genome-wide array comparative genomic hybridization. Finally, by detailed clinical characterization we provide evidence that heterozygous mutations in KAT6A cause a distinct intellectual disability syndrome. The common phenotype includes hypotonia, intellectual disability, early feeding and oromotor difficulties, microcephaly and/or craniosynostosis, and cardiac defects in combination with subtle facial features such as bitemporal narrowing, broad nasal tip, thin upper lip, posteriorly rotated or low-set ears, and microretrognathia. The identification of human subjects complements previous work from mice and zebrafish where knockouts of Kat6a/kat6a lead to developmental defects. NM_001099412.1相似文献
85.
86.
We report results of the studies relating to the fabrication and characterization of novel biosensing electrode by covalent immobilization of DNA onto microstructural cystine (Cys) prepared by acoustic cavitation method. The TEM investigations of these structures reveal transformation of microstructured Cys from nanorods to dendritic structure under optimum conditions. The Cys dendrites (denCys) have been investigated by XRD, FT-IR, and SEM studies. These biosensing electrodes have been fabricated by immobilization of Escherichia coli (E. coli)-specific DNA probe onto the dendritic cystine. The results of the electrochemical impedance spectroscopy studies reveal that this nucleic acid sensor exhibits linear response to cDNA in the concentration range of 10(-6) to 10(-14) M with response time of 30 min. The biosensing characteristics show that the fabricated E. coli sensor can be reused about 4 times and is stable for ~4 weeks. The studies on cross-reactivity of the sensor for other water-borne pathogens like Salmonella typhimurium, Neisseria meningitides, and Klebsiella pneumonia reveal specificity of the bioelectrode for E. coli detection. 相似文献
87.
Identification of haptoglobin and apolipoprotein A-I as biomarkers for high altitude pulmonary edema
Ahmad Y Shukla D Garg I Sharma NK Saxena S Malhotra VK Bhargava K 《Functional & integrative genomics》2011,11(3):407-417
We have investigated the plasma proteome using 2D gel electrophoresis and matrix-assisted laser desorption/ionization tandem
time of flight from patients with high altitude pulmonary edema (HAPE). A complete proteomic analysis was performed on 20
patients with HAPE and ten healthy sea level controls. In total, we have identified 25 protein spots in human plasma and found
that 14 of them showed altered changes in HAPE patients, which mainly were acute phase proteins (APPs), compliment components,
and apolipoproteins among others. Among the APPs, haptoglobin α2 chain, haptoglobin β chain, transthyretin, and plasma retinol
binding precursor showed overexpression in HAPE patients as compared to controls. To validate the result of proteomic analysis,
two proteins were selected for enzyme-linked immunosorbent assay and Western blotting analysis. Our data conclusively shows
that two proteins, haptoglobin and apolipoprotein A-I are upregulated in plasma of HAPE patients. These proteins may provide
a fast and effective control of inflammatory damage until the subsequent mechanisms can begin to operate. Taken together,
our findings further support the hypothesis that inflammatory response system is linked to the pathophysiology of HAPE. 相似文献
88.
89.
90.
Om P. Malhotra W.B. Rippon D.D. Solomon A.G. Walton 《International journal of biological macromolecules》1979,1(3):137-143
Structural aspects of the behaviour of prothrombin and its fragments have been examined by circulae dichroism spectroscopy. It has been noted that a correlation exists between the ellipticity of the aromatic bands and the physiological activity of partially denatured and abnormal prothrombins. The origin of these bands appears to be predominantly based in the region of one or more tyrosine residues. It is shown that whereas complexation of calcium with prothrombin causes little change in the dromatic c.d. spectrum, the effect on prothrombin fragment 1 is quite dramatic. It is concluded that the binding of calcium to the dicarboxyglutamate residues in fragment 1 causes a concomitant ionization of one or more tyrosine residues. The behaviour of fragment 1 is indicative of an intact protein with a tertiary structure which supports our previous trimodular model of prothrombin, which is activated in part by the unlocking of an ‘ionic’ lock. This lock consists of the highly negatively charged dicarboxyglutamyl patch at or near the N terminus of prothrombin and a positively charged basic patch near the C terminus. 相似文献