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Described here is a three-day protocol that directly yields DNA sequence after isolating and PCR amplifying genomic DNA from a small sample of frozen nasopharyngeal carcinoma tissue embedded in optimal cutting temperature (OCT) compound. The method is consistently successful, reproducible and will facilitate the rapid analysis of DNA sequence from very small samples. 相似文献
3.
Elizabeth A. Colburn 《Hydrobiologia》1988,158(1):215-226
Salinity is a major factor influencing the distributions and abundances of aquatic macroinvertebrates of saline waters in Death Valley, California, USA. A general pattern of declining numbers of species with increasing salinity is seen in Death Valley waters. Some species are restricted to low salinities, others are found only in highly saline pools, and still others are widely distributed over a broad range of salinities.Salinity alone cannot explain distributions seen in the field. Distributions and abundances of species such as the caddisfly Limnephilus assimilis Banks are broader than would be predicted on the basis of laboratory studies of salinity and temperature. I present evidence that for such species, biotic factors such as reduced predation at high salinities may compensate for increased physiological stress. 相似文献
4.
The interaction of sulfated mucopolysaccharides and lectins has been studied by determining the amount of precipitate formed when mucopolysaccharides are added to a solution of concanavalin A or a partially purified lectin preparation from red kidney bean (Phaseolus vulgaris). The amount of insoluble complex obtained when a given mucopolysaccharide is added to a solution of partially purified red kidney bean preparation is pH dependent. The reaction of concanavalin A and heparin has also been studied by adding increasing amounts of mucopolysaccharide to a fixed amount of lectin. This interaction results in the development of a precipitin-like curve and leads to the isolation of a heparin fraction which has been found to be more reactive with respect to formation of a precipitate than the original heparin preparation. Monosaccharides such as α-methyl-d-mannopyranoside and N-acetyl-d-glucosamine which are known to bind specifically to the lectin, greatly inhibit precipitate formation. The interactions between sulfated mucopolysaccharides and lectins have been used to isolate various sulfated mucopolysaccharides. 相似文献
5.
Listeria species and L. monocytogenes were found in 81 and 62%, respectively, of fresh or low-salinity waters (37 samples) in tributaries draining into Humboldt-Arcata Bay, Calif., during a winter (January-February) sampling period. The incidence of Listeria species and L. monocytogenes in sediment (46 samples) from the same sites where water was sampled was 30.4 and 17.4%, respectively. One of three bay water samples contained Listeria species (including L. monocytogenes), while of 35 samples of oysters examined, only 1 was found positive for Listeria species (L. innocua). A given species or L. monocytogenes serogroup appeared to predominate in fresh water when domesticated animals (cows, horses) were nearby, whereas greater variety with no species predominance was observed in areas with no direct animal influence. 相似文献
6.
W A Colburn 《Steroids》1974,24(1):95-106
A radioimmunoassay for the measurement of prednisone in serum has been developed. The method is accurate, precise, specific, and very sensitive. Using a primary antibody elicited against prednisone 21-hemisuccinate-bovine serum albumin and a chemical precipitation step, the assay is capable of detecting 6.25 picograms of prednisone in 0.1 ml of unextracted diluted serum or plasma.The specificity of the assay is influenced by the carbonyl groups at position 11 and 20, and the double bond at the 1-position of the steroid nucleus. Physiological levels of endogenous steroid interfered only slightly with the primary antibody.Measurement of serum concentrations of prednisone in man and dog were accomplished following the administration of prednisone (Deltasone®). This assay, used in conjunction with a published radioimmunoassay for prednisolone (1), can be used to determine the interconversion of these two drug products following prednisone or prednisolone administration. 相似文献
7.
Panizo María Mercedes Ferrara Giuseppe García Nataly Moreno Xiomara Navas Trina Calderón Enrique 《Current fungal infection reports》2020,14(1):29-39
Current Fungal Infection Reports - The aim of this work is to contribute to the knowledge of diagnosis, burden, and mortality of pneumocystosis or Pneumocystis jirovecii pneumonia (PCP) in... 相似文献
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Ruth Muchekehu Dingguo Liu Mark Horn Lioudmila Campbell Joselyn Del Rosario Michael Bacica Haim Moskowitz Trina Osothprarop Anouk Dirksen Venkata Doppalapudi Allan Kaspar Steven R. Pirie-Shepherd Julia Coronella 《Translational oncology》2013,6(5):562-IN6
Poor drug delivery and penetration of antibody-mediated therapies pose significant obstacles to effective treatment of solid tumors. This study explored the role of pharmacokinetics, valency, and molecular weight in maximizing drug delivery. Biodistribution of a fibroblast growth factor receptor 4 (FGFR4) targeting CovX-body (an FGFR4-binding peptide covalently linked to a nontargeting IgG scaffold; 150 kDa) and enzymatically generated FGFR4 targeting F(ab)2 (100 kDa) and Fab (50 kDa) fragments was measured. Peak tumor levels were achieved in 1 to 2 hours for Fab and F(ab)2versus 8 hours for IgG, and the percentage injected dose in tumors was 0.45%, 0.5%, and 2.5%, respectively, compared to 0.3%, 2%, and 6% of their nontargeting controls. To explore the contribution of multivalent binding, homodimeric peptides were conjugated to the different sized scaffolds, creating FGFR4 targeting IgG and F(ab)2 with four peptides and Fab with two peptides. Increased valency resulted in an increase in cell surface binding of the bivalent constructs. There was an inverse relationship between valency and intratumoral drug concentration, consistent with targeted consumption. Immunohistochemical analysis demonstrated increased size and increased cell binding decreased tumor penetration. The binding site barrier hypothesis suggests that limited tumor penetration, as a result of high-affinity binding, could result in decreased efficacy. In our studies, increased target binding translated into superior efficacy of the IgG instead, because of superior inhibition of FGFR4 proliferation pathways and dosing through the binding site barrier. Increasing valency is therefore an effective way to increase the efficacy of antibody-based drugs. 相似文献
10.
Hannah A. DeBerg Benjamin H. Blehm Janet Sheung Andrew R. Thompson Carol S. Bookwalter Seyed F. Torabi Trina A. Schroer Christopher L. Berger Yi Lu Kathleen M. Trybus Paul R. Selvin 《The Journal of biological chemistry》2013,288(45):32612-32621
Disruptions in microtubule motor transport are associated with a variety of neurodegenerative diseases. Post-translational modification of the cargo-binding domain of the light and heavy chains of kinesin has been shown to regulate transport, but less is known about how modifications of the motor domain affect transport. Here we report on the effects of phosphorylation of a mammalian kinesin motor domain by the kinase JNK3 at a conserved serine residue (Ser-175 in the B isoform and Ser-176 in the A and C isoforms). Phosphorylation of this residue has been implicated in Huntington disease, but the mechanism by which Ser-175 phosphorylation affects transport is unclear. The ATPase, microtubule-binding affinity, and processivity are unchanged between a phosphomimetic S175D and a nonphosphorylatable S175A construct. However, we find that application of force differentiates between the two. Placement of negative charge at Ser-175, through phosphorylation or mutation, leads to a lower stall force and decreased velocity under a load of 1 piconewton or greater. Sedimentation velocity experiments also show that addition of a negative charge at Ser-175 favors the autoinhibited conformation of kinesin. These observations imply that when cargo is transported by both dynein and phosphorylated kinesin, a common occurrence in the cell, there may be a bias that favors motion toward the minus-end of microtubules. Such bias could be used to tune transport in healthy cells when properly regulated but contribute to a disease state when misregulated. 相似文献