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151.
152.
Selfing and inbreeding depression in seeds and seedlings of Neobalanocarpus heimii (Dipterocarpaceae) 总被引:1,自引:0,他引:1
Naito Y Konuma A Iwata H Suyama Y Seiwa K Okuda T Lee SL Muhammad N Tsumura Y 《Journal of plant research》2005,118(6):423-430
We evaluated the degree of selfing and inbreeding depression at the seed and seedling stages of a threatened tropical canopy tree, Neobalanocarpus heimii, using microsatellite markers. Selection resulted in an overall decrease in the level of surviving selfed progeny from seeds to established seedlings, indicating inbreeding depression during seedling establishment. Mean seed mass of selfed progeny was lower than that of outcrossed progeny. Since the smaller seeds suffered a fitness disadvantage at germination in N. heimii, the reduced seed mass of selfed progeny would be one of the determinants of the observed inbreeding depression during seedling establishment. High selfing rates in some mother trees could be attributed to low local densities of reproductive individuals, thus maintenance of a sufficiently high density of mature N. heimii should facilitate regeneration and conservation of the species. 相似文献
153.
Kaisho Y Watanabe T Nakata M Yano T Yasuhara Y Shimakawa K Mori I Sakura Y Terao Y Matsui H Taketomi S 《Biochemical and biophysical research communications》2005,330(3):653-657
The human MrgX3 gene, belonging to the mrgs/SNSRs (mas related genes/sensory neuron specific receptors) family, was overexpressed in transgenic rats using the actin promoter. Two animal lines showed cataracts with liquification/degeneration and swelling of the lens fiber cells. The transient epidermal desquamation was observed in line with higher gene expression. Histopathology of the transgenic rats showed acanthosis and focal parakeratosis. In the epidermis, there was an increase in cellular keratin 14, keratin 10, and loricrin, as well as PGP 9.5 in innervating nerve fibers. These phenotypes accompanied an increase in the number of proliferating cells. These results suggest that overexpression of the human MrgX3 gene causes a disturbance of the normal cell-differentiation process. 相似文献
154.
Yoshihiko Chiba Ayako Ueno Koji Shinozaki Hisao Takeyama Shuji Nakazawa Hiroyasu Sakai Miwa Misawa 《Respiratory research》2005,6(1):4
Background
It has recently been suggested that RhoA plays an important role in the enhancement of the Ca2+ sensitization of smooth muscle contraction. In the present study, a participation of RhoA-mediated Ca2+ sensitization in the augmented bronchial smooth muscle (BSM) contraction in a murine model of allergic asthma was examined.Methods
Ovalbumin (OA)-sensitized BALB/c mice were repeatedly challenged with aerosolized OA and sacrificed 24 hours after the last antigen challenge. The contractility and RhoA protein expression of BSMs were measured by organ-bath technique and immunoblotting, respectively.Results
Repeated OA challenge to sensitized mice caused a BSM hyperresponsiveness to acetylcholine (ACh), but not to high K+-depolarization. In α-toxin-permeabilized BSMs, ACh induced a Ca2+ sensitization of contraction, which is sensitive to Clostridium botulinum C3 exoenzyme, indicating that RhoA is implicated in this Ca2+ sensitization. Interestingly, the ACh-induced, RhoA-mediated Ca2+ sensitization was significantly augmented in permeabilized BSMs of OA-challenged mice. Moreover, protein expression of RhoA was significantly increased in the hyperresponsive BSMs.Conclusion
These findings suggest that the augmentation of Ca2+ sensitizing effect, probably via an up-regulation of RhoA protein, might be involved in the enhanced BSM contraction in antigen-induced airway hyperresponsiveness. 相似文献155.
Shimokawa Y Akiyama H Kashiyama E Koga T Miyamoto G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,821(1):8-14
High performance liquid chromatographic (HPLC) methods were validated for the determination of aripiprazole (OPC-14597, Abilify) in rat plasma and brain. Separation was by Nova-pak phenyl column; flow rate, 1.0 ml/min; mobile phase, acetonitrile-methanol-20 mM sodium sulfate-acetic acid (27:25:48:1, v/v/v/v); UV detection at 254 nm. Reproducibility in plasma and brain showed excellent precision (within 7.8 and 10.6%) and accuracy (96.0-102.4% and 99.0-108.7%) with calibration curve ranges 10.0-2000 ng/ml and 30.0-6000 ng/g, respectively. Validated HPLC methods were successfully applied to pharmacokinetic study of aripiprazole in rats, demonstrating brain concentrations after oral administration five times higher than plasma concentrations. 相似文献
156.
Wheat cultivar-specific proteins in grain revealed by 2-DE and their application to cultivar identification of flour 总被引:4,自引:0,他引:4
Yahata E Maruyama-Funatsuki W Nishio Z Tabiki T Takata K Yamamoto Y Tanida M Saruyama H 《Proteomics》2005,5(15):3942-3953
Wheat flour proteins were studied to identify the cultivar-specific proteins and use them to identify cultivars in flours. Proteins extracted from flours of Japanese wheat (cultivars Hokushin, Horoshirikomugi, Kitanokaori and Kachikei 33) and Canadian wheat (Canada Western Red Spring Wheat No. 1; 1CW) were analyzed by 2-DE with IEF gels over three pH ranges: pH 4-7, pH 5-8, and pH 6-11. This system enabled detection of more than 1600 protein spots. We recognized that among 50 protein spots showing cultivar-dependent qualitative changes, 25 proteins were wheat cultivar specific. These 50 protein spots were analyzed by N-terminal Edman degradation microsequencing and MALDI-TOF-MS; 21 protein spots were storage proteins, such as gliadin and low-molecular mass glutenin subunit. Five protein spots were identified as dehydroascorbate reductase (Triticum aestivum), triticin precursor (T. aestivum), alpha-amylase inhibitor (Oryza sativa), DNA-binding with one finger (Dof) zinc family protein (O. sativa), and nonphototropic hypocotyl 1 (NPH1) protein (Avena sativa). The other protein spots appeared to be hypothetical proteins (O. sativa or Arabidopsis thaliana) or functional unknown proteins. These specific proteins can be used as markers to identify wheat cultivars in blended flour composed of two or three flours. 相似文献
157.
Shimazu M Sekito T Akiyama K Ohsumi Y Kakinuma Y 《The Journal of biological chemistry》2005,280(6):4851-4857
Among the members of the major facilitator superfamily of Saccharomyces cerevisiae, we identified genes involved in the transport into vacuoles of the basic amino acids histidine, lysine, and arginine. ATP-dependent uptake of histidine and lysine by isolated vacuolar membrane vesicles was impaired in YMR088c, a vacuolar basic amino acid transporter 1 (VBA1)-deleted strain, whereas uptake of tyrosine or calcium was little affected. This defect in histidine and lysine uptake was complemented fully by introducing the VBA1 gene and partially by a gene encoding Vba1p fused with green fluorescent protein, which was determined to localize exclusively to the vacuolar membrane. A defect in the uptake of histidine, lysine, or arginine was also observed in the vacuolar membrane vesicles of mutants YBR293w (VBA2) and YCL069w (VBA3). These three VBA genes are closely related phylogenetically and constitute a new family of basic amino acid transporters in the yeast vacuole. 相似文献
158.
Sequential conversion of molecular oxygen into peroxo- and hydroperoxo-metal species involved in an effective O2-activation is verified for the TpiPr2Rh system by isolation and characterization of the intermediates. O2-treatment of the Rh(I) precursor, TpiPr2Rh(dppe) (1), in the presence of 3,5-diisopropylpyrazole (H-pziPr2) gives the κ2-peroxometal complex, TpiPr2(H-pziPr2)Rh(κ2-O2) (2), which is subsequently converted to the hydroperoxo complex, TpiPr2(H-pzH2)(pzH2)Rh-OOH (4), upon treatment with pyrazole (H-pzH2). The peroxo species 2 and 4 have been characterized by spectroscopic and crystallographic methods and it is revealed that, in the present N-rich coordination system, the basic peroxo ligands (O2, OOH) form hydrogen-bonding interactions with the proximal N- and NH-functional groups. 相似文献
159.
Zhou Z Yamamoto Y Sugai F Yoshida K Kishima Y Sumi H Nakamura H Sakoda S 《The Journal of biological chemistry》2004,279(26):27320-27326
Hepatoma-derived growth factor (HDGF) is a heparin-binding proliferating factor originally isolated from conditioned medium of the hepatoma-derived cell line HuH-7. HDGF has greatest homology in an amino acid sequence with high mobility group 1 (HMG1), which has been characterized as a DNA-binding, inflammatory, and potent neurite outgrowth molecule. HDGF is reported to be widely expressed and act as a growth factor in many kinds of cells. However, it has not been investigated in the nervous system. Here, we show by Western blot analysis that HDGF is present in the mouse brain from the embryonic period until adulthood. In situ hybridization and immunohistochemical analyses revealed that HDGF was expressed mainly in neurons, and HDGF protein was localized to the nucleus. HDGF and high mobility group 1 were secreted under physiological conditions and released extracellularly in necrotic conditions. Furthermore, we showed that exogenously supplied HDGF had a neurotrophic effect and was able to partially prevent the cell death of neurons in which endogenous HDGF was suppressed. Therefore, we propose that HDGF is a novel type of neurotrophic factor, on account of its localization in the nucleus and its potential to function in an autocrine manner under both physiological and pathological conditions throughout life. 相似文献
160.
Tashima Y Oe R Lee S Sugihara G Chambers EJ Takahashi M Yamada T 《The Journal of biological chemistry》2004,279(17):17587-17595
In order to investigate the influence of cholesterol (Ch) and monosialoganglioside (GM1) on the release and subsequent deposition/aggregation of amyloid beta peptide (Abeta)-(1-40) and Abeta-(1-42), we have examined Abeta peptide model membrane interactions by circular dichroism, turbidity measurements, and transmission electron microscopy (TEM). Model liposomes containing Abeta peptide and a lipid mixture composition similar to that found in the cerebral cortex membranes (CCM-lipid) have been prepared. In all, four Abeta-containing liposomes were investigated: CCM-lipid; liposomes with no GM1 (GM1-free lipid); those with no cholesterol (Ch-free lipid); liposomes with neither cholesterol nor GM1 (Ch-GM1-free lipid). In CCM liposomes, Abeta was rapidly released from membranes to form a well defined fibril structure. However, for the GM1-free lipid, Abeta was first released to yield a fibril structure about the membrane surface, then the membrane became disrupted resulting in the formation of small vesicles. In Ch-free lipid, a fibril structure with a phospholipid membrane-like shadow formed, but this differed from the well defined fibril structure seen for CCM-lipid. In Ch-GM1-free lipid, no fibril structure formed, possibly because of membrane solubilization by Abeta. The absence of fibril structure was noted at physiological extracellular pH (7.4) and also at liposomal/endosomal pH (5.5). Our results suggest a possible role for both Ch and GM1 in the membrane release of Abeta from brain lipid bilayers. 相似文献