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271.
Fujimori A Hashimoto H Araki R Saito T Sato S Kasama Y Tsutsumi Y Mori M Fukumura R Ohhata T Tatsumi K Abe M 《Radiation research》2002,157(3):298-305
The catalytic subunit of DNA-dependent protein kinase plays critical roles in nonhomologous end joining in repair of DNA double-strand breaks and V(D)J recombination. In addition to the SCID phenotype, it has been suggested that the molecule contributes to the polymorphic variations in radiosensitivity and susceptibility to cancer in mouse strains. Here we show the nucleotide sequence of approximately 193-kbp and 84-kbp genomic regions encoding the entire Prkdc gene (also known as DNA-PKcs) in the mouse and chicken, respectively. A large retroposon was found in intron 51 in the mouse but not in the human or chicken. Comparative analyses of the genome strongly suggested that the region contains only two genes for Prkdc and Mcm4; however, several conserved sequences and cis elements were also predicted. 相似文献
272.
Norihide Hinomoto Masahiko Muraji Takashi Noda Toru Shimizu Kenjiro Kawasaki 《Biological Control》2004,31(3):642
We developed multiplex polymerase chain reaction methods to identify five Orius (Heteroptera: Anthocoridae) species that occur commonly in Japan: Orius sauteri, Orius minutus, Orius strigicollis, Orius nagaii, and Orius tantillus. The method amplified internal transcribed spacer 1 of the nuclear ribosomal DNA by using five primers simultaneously and produced species-specific banding patterns upon agarose gel electrophoresis. Reliability of the method was tested for 350 individuals of 23 strains, and consistent results were obtained. Dichotomous keys are also provided for easy and quick species identification. 相似文献
273.
Imura T Ito S Azumi R Yanagishita H Sakai H Abe M Kitamoto D 《Biotechnology letters》2007,29(6):865-870
A carbohydrate ligand system has been developed which is composed of self-assembled monolayers (SAMs) of mannosylerythritol
lipid-A (MEL-A) from Pseudozyma antarctica, serving for human immunoglobulin G and M (HIgG and HIgM). The estimated binding constants from surface plasmon resonance
(SPR) measurement were K
a = 9.4 × 106 M−1 for HIgG and 5.4 × 106 M−1 for HIgM, respectively. The binding site was not in the Fc region of immunoglobulin but in the Fab region. Large amounts
of HIgG and HIgM bound to MEL-A SAMs were directly observed by atomic force microscopy. 相似文献
274.
Nakazawa T Takahashi H Nishijima K Shimura M Fuse N Tamai M Hafezi-Moghadam A Nishida K 《Journal of neurochemistry》2007,100(4):1018-1031
Excitotoxicity is a major cause of retinal ganglion cell (RGC) death during ischemic diseases such as vessel occlusion and diabetic retinopathy. However, the underlying mechanisms are not well understood. Statins, inhibitors of the HMG-CoA reductase, have neuroprotective effects in addition to their original role in lowering cholesterol. We hypothesize that pitavastatin, a recently introduced potent statin, is protective against N-methyl-d-aspartic acid (NMDA)-induced RGC death. Pitavastatin, administered by gavage, abolished NMDA-induced loss of RGCs. To elucidate the mechanisms underlying the neuroprotective effect of pitavastatin, we investigated its impact on inflammation. NMDA increased the expression of interleukin-1beta and TNF-alpha, and endothelial adhesion molecules, including ICAM-1, and induced leukocyte accumulation in the retinal vessels. Pitavastatin significantly reduced NMDA-induced leukocyte accumulation and up-regulation of endothelial adhesion molecules, whereas cytokine expression was unaffected. Systemic blockade of ICAM-1 in wild-type mice or absence of CD18 in gene-deficient (CD18(-/-)) mice significantly suppressed NMDA-induced leukocyte accumulation and RGC death. These findings suggest a novel and causative role for inflammatory leukocyte recruitment in NMDA-induced excitotoxicity. Furthermore, we show the novel neuroprotective effect of statins against excitotoxicity-induced RGC death. Statins or other anti-inflammatory agents may thus have therapeutic benefits in excitotoxicity-associated neuronal diseases through blockade of leukocyte recruitment. 相似文献
275.
Bessho M Ohnishi I Matsuyama J Matsumoto T Imai K Nakamura K 《Journal of biomechanics》2007,40(8):1745-1753
Hip fractures are the most serious complication of osteoporosis and have been recognized as a major public health problem. In elderly persons, hip fractures occur as a result of increased fragility of the proximal femur due to osteoporosis. It is essential to precisely quantify the strength of the proximal femur in order to estimate the fracture risk and plan preventive interventions. CT-based finite element analysis could possibly achieve precise assessment of the strength of the proximal femur. The purpose of this study was to create a simulation model that could accurately predict the strength and surface strains of the proximal femur using a CT-based finite element method and to verify the accuracy of our model by load testing using fresh frozen cadaver specimens. Eleven right femora were collected. The axial CT scans of the proximal femora were obtained with a calibration phantom, from which the 3D finite element models were constructed. Materially nonlinear finite element analyses were performed. The yield and fracture loads were calculated, while the sites where elements failed and the distributions of the principal strains were determined. The strain gauges were attached to the proximal femoral surfaces. A quasi-static compression test of each femur was conducted. The yield loads, fracture loads and principal strains of the prediction significantly correlated with those measured (r=0.941, 0.979, 0.963). Finite element analysis showed that the solid elements and shell elements in undergoing compressive failure were at the same subcapital region as the experimental fracture site. 相似文献
276.
Loss of anthocyanins in red-wine grape under high temperature 总被引:10,自引:0,他引:10
277.
Comuzzie AG Tejero ME Funahashi T Martin LJ Kissebah A Takahashi M Kihara S Tanaka S Rainwater DL Matsuzawa Y MacCluer JW Blangero J 《Human biology; an international record of research》2007,79(2):191-200
Results from previous studies suggest that adiponectin levels are associated with risk factors for cardiovascular disease and type 2 diabetes mellitus; however, the genetic and/or environmental components of this relationship have not been characterized. The aims of this study were (1) to assess the presence of pleiotropy between adiponectin levels and risk factors for cardiovascular disease and (2) to study the association of circulating levels of adiponectin with risk factors for cardiovascular disease in the absence and presence of obesity in Mexican American adults from the San Antonio Family Heart Study. Body composition and circulating levels of adiponectin, leptin, and lipid subfractions and measurements of glucose metabolism were measured in 898 subjects. The mean and standard error of the circulating levels of adiponectin was 8.7 +/- 3.2 microg/ml. Bivariate quantitative analyses between adiponectin levels and phenotypes related to cardiovascular disease and type 2 diabetes mellitus were conducted using the variance decomposition approach implemented in SOLAR. A second analysis in unrelated subjects compared these risk factors between sex- and age-matched lean and obese subjects with high and low adiponectin levels. We found significant evidence of pleiotropy (i.e., shared genetic effects) between plasma levels of adiponectin and well-established risk factors for cardiovascular disease and type 2 diabetes mellitus. Individuals with low adiponectin levels per body weight had more adverse risk profiles. These findings offer new insights into the genetic connection between increasing adiposity and risk for cardiovascular disease and type 2 diabetes mellitus, and they suggest that adiponectin may be an important risk factor for the development of these conditions. 相似文献
278.
Kenichi Fujisawa Masakazu Takahata 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(1):127-140
We investigated how the physiological characteristics and synaptic activities of nonspiking giant interneurons (NGIs), which
integrate sensory inputs in the brain and send synaptic outputs to oculomotor neurons innervating eyestalk muscles, changed
after unilateral ablation of the statocyst in order to clarify neuronal mechanisms underlying the central compensation process
in crayfish. The input resistance and membrane time constant in recovered animals that restored the original symmetrical eyestalk
posture 2 weeks after operation were significantly greater than those immediately after operation on the operated side whereas
in non-recovered animals only the membrane time constant showed a significant increase. On the intact side, both recovered
and non-recovered animals showed no difference. The frequency of synaptic activity showed a complex pattern of change on both
sides depending on the polarity of the synaptic potential. The synaptic activity returned to the bilaterally symmetrical level
in recovered animals while bilateral asymmetry remained in non-recovered ones. These results suggest that the central compensation
of eyestalk posture following unilateral impairment of the statocyst is subserved by not only changes in the physiological
characteristics of the NGI membrane but also the activity of neuronal circuits presynaptic to NGIs. 相似文献
279.
Shiina I Sano Y Nakata K Suzuki M Yokoyama T Sasaki A Orikasa T Miyamoto T Ikekita M Nagahara Y Hasome Y 《Bioorganic & medicinal chemistry》2007,15(24):7599-7617
Two new synthetic pathways to the anti-cancer agent tamoxifen and its derivatives were developed. The first route involved the aldol reaction of benzyl phenyl ketone with acetaldehyde followed by Friedel–Crafts substitution with anisole in the presence of Cl2Si(OTf)2 to produce 1,1,2-triaryl-3-acetoxybutane, a precursor of the tamoxifen derivatives. The second one utilized the novel three-component coupling reaction among aromatic aldehydes, cinnamyltrimethylsilane, and aromatic nucleophiles using HfCl4 as a Lewis acid catalyst to produce 3,4,4-triarylbutene, that is also a valuable intermediate of the tamoxifen derivatives. The former strategy requires a total of 10 steps from the aldol formation to the final conversion to tamoxifen, whereas the latter needs only three or four steps to produce tamoxifen and droloxifene including the installation of the side-chain moiety and the base-induced double-bond migration to form the tetra-substituted olefin structure. This synthetic strategy seems to serve as a new and practical pathway to prepare not only the tamoxifen derivatives but also the other SERMs (selective estrogen receptor modulators) including estrogen-dependent breast cancer and osteoporosis agents. 相似文献
280.
Yan H Saika H Maekawa M Takamure I Tsutsumi N Kyozuka J Nakazono M 《Genes & genetic systems》2007,82(4):361-366
Senescence or cell death in plant leaves is known to be inducible by darkness or H(2)O(2). When the Arabidopsis gene MAX2/ORE9 is disrupted, leaf senescence or cell death in response to the above stimuli is delayed. Because the rice (Oryza sativa L.) gene DWARF3 (D3) is orthologous to MAX2/ORE9, we wished to know whether disruption of D3 also results in increased longevity in leaves. We found that darkness-induced senescence or H(2)O(2)-induced cell death in the third leaf [as measured by chlorophyll degradation, membrane ion leakage and expression of senescence-associated genes (SAGs)] in a d3 rice mutant was delayed by 1-3 d compared to that in its reference line Shiokari. Moreover, the mRNA levels of D3, HTD1 and D10, which are orthologs of Arabidopsis MAX2/ORE9, MAX3 and MAX4, respectively, increased during cell death. These results suggest that D3 protein in rice, like MAX2/ORE9 in Arabidopsis, is involved in leaf senescence or cell death. 相似文献