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141.
Khajehdehi Mina Khalaj-Kondori Mohammad Hosseinpour Feizi Mohammad Ali 《Molecular biology reports》2022,49(7):6075-6084
Molecular Biology Reports - Aberrant expressions of long non-coding RNAs promote cancer development including colorectal cancer. Expression profiling of cancer-related lncRNAs may introduce new... 相似文献
142.
Tadros MI 《AAPS PharmSciTech》2008,9(1):243-249
The purpose of this research was to evaluate the variables that are suggested to influence the adsorption of the hydrophilic
hyaluronic acid (HA) onto the surface of the hydrophobic betamethasone-17-valerate (BV) particles in order to formulate a
nebulizable suspension. The adsorption of HA from aqueous solutions (0.04% to 0.16%, w/v) to a fixed BV concentration (0.04%, w/v) under different experimental conditions, was investigated. The method of preparation of HA-BV suspensions involved suspending
BV particles either in the hydrated HA solution (method 1) or in water followed by addition of solid HA (method 2). Other
variables like the time required for the adsorption to complete and temperature at which adsorption is carried out were studied.
The nebulization of the suspensions was tested via an air jet nebulizer connected to a twin stage impinger. In order to improve
the nebulization behavior of the optimized suspension, l-leucine or sodium taurocholate was incorporated in increasing concentrations (0.01–0.04%, w/v). The optimized suspension, having a nebulization efficiency of 33.75%, was achieved following the adsorption of HA (0.1%,
w/v) onto BV particles adopting method 2 of preparation and extending for three days at 4 °C. Incorporation of either l-leucine
or sodium taurocholate significantly decreased the aggregate size of the optimized suspension and consequently caused significant
increases in the nebulization efficiency to reach 46.87% and 56.25%, respectively.
An erratum to this article is available at . 相似文献
143.
Despite the widespread use of hCG to advance ovulation in the mare there is little information on efficacy of dose rates and any contraindications of its use. This study aims to investigate the effect of dose of hCG on ovulation within 48h and the effect of hCG on: ovulation, multiple ovulation (MO), pregnancy, multiple pregnancy (MP) rates and synchrony of MO; additionally whether any seasonal effect is evident. Sequential ultrasonic scanning was used to monitor the occurrence of ovulation, within 48h of treatment, in 1291 Thoroughbred mares treated with either 750iu hCG or 1500iu hCG s.c. Ovulation rate, type (single ovulations (SO), MO, synchronous, asynchronous) and subsequent pregnancy were then monitored in 1239 Thoroughbred mares on a commercial stud over 3 years, 536 of which were treated with 750iu hCG at mating, all mares were also allocated into groups according to month of mating. No significant difference existed between the two dose levels of hCG and no significant difference existed between treated and untreated mares in overall ovulations (1.32 and 1.28 respectively), MO (31.7% and 27.7%), pregnancy (65.1% and 65.6%) or MP rates (10.8% and 11.8%). There was no significant association between month of year and pregnancy or MP rates for either treated or control mares, nor for MO for untreated mares. A significant (p<0.05) association was evident between month and MO in treated mares, MO being lowest in April (22.3%). 95.9% of treated mares multiple ovulated within 48h compared with 90.7% controls, a near significant difference. In conclusion this study demonstrates that: (i) hCG dose of 750iu s.c. is just as effective in inducing ovulation within 48h as 1500iu, (ii) 750iu hCG has no significant effect on ovulation, MO, pregnancy or MP rates; (iii) a significant (p<0.05) association exists between season and MO in hCG treated mares; (iv) a tighter synchrony (ovulation within 48h) of MO is evident in hCG treated compared with control mares (p=0.052). 相似文献
144.
We developed a method of effective peptide screening that combines experiments and computational analysis. The method is based on the concept that screening efficiency can be enhanced from even limited data by use of a model derived from computational analysis that serves as a guide to screening and combining the model with subsequent repeated experiments. Here we focus on cell-adhesion peptides as a model application of this peptide-screening strategy. Cell-adhesion peptides were screened by use of a cell-based assay of a peptide array. Starting with the screening data obtained from a limited, random 5-mer library (643 sequences), a rule regarding structural characteristics of cell-adhesion peptides was extracted by fuzzy neural network (FNN) analysis. According to this rule, peptides with unfavored residues in certain positions that led to inefficient binding were eliminated from the random sequences. In the restricted, second random library (273 sequences), the yield of cell-adhesion peptides having an adhesion rate more than 1.5-fold to that of the basal array support was significantly high (31%) compared with the unrestricted random library (20%). In the restricted third library (50 sequences), the yield of cell-adhesion peptides increased to 84%. We conclude that a repeated cycle of experiments screening limited numbers of peptides can be assisted by the rule-extracting feature of FNN. 相似文献
145.
To investigate the effects of cell-cell interactions on cellular function, the microenvironment surrounding cells should be precisely controlled. Here, we describe a cell patterning technique, which utilizes magnetic force and magnetite nanoparticles. This method was used to develop cell culture arrays for investigation of cell behaviors in angiogenesis. Pin holder devices that contain more than 6,000 pillars on the surface are used for fabricating the cell culture arrays by setting it on a magnet. The magnetically labeled cells were arranged by magnetic distribution. When the human umbilical vein endothelial cells are arranged at 250 microm intervals (5.9 cells/spot), the cells spread toward other cell cluster on adjacent spots in 4.5 h, and formed cord-like structures in 8.5 h. It was shown that cell-cell interactions were successfully investigated using magnetic cell arrangement. 相似文献
146.
147.
Mina Song Jae Eun Park Sung Goo Park Hyung-Kyoon Choi Seong Eon Ryu Sayeon Cho 《Biochemical and biophysical research communications》2009,381(4):491-6837
Protein phosphorylation plays critical roles in many regulatory mechanisms controlling cell activities and thus involved in various diseases. The cellular equilibrium of phosphorylation is regulated through the actions of protein kinases and phosphatases. Therefore, these regulatory proteins have emerged as promising targets for drug development. In this study, we screened protein tyrosine phosphatases (PTPs) by in vitro phosphatase assays to identify PTPs that are inhibited by 8-hydroxy-7-(6-sulfonaphthalen-2-yl)diazenyl-quinoline-5-sulfonic acid (NSC-87877), a potent inhibitor of SHP-1 and SHP-2 PTPs. Phosphatase activity of dual-specificity protein phosphatase 26 (DUSP26) was decreased by the inhibitor in a dose-dependent manner. Kinetic studies with NSC-87877 and DUSP26 revealed a competitive inhibition. NSC-87877 effectively inhibited DUSP26-mediated dephosphorylation of p38, a member of mitogen-activated protein kinase (MAPK) family. Since DUSP26 is involved in survival of anaplastic thyroid cancer (ATC) cells, NSC-87877 could be a therapeutic reagent for treating ATC. 相似文献
148.
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150.
Andersen K Mori H Fata J Bascom J Oyjord T Mælandsmo GM Bissell M 《Developmental biology》2011,352(2):581-190
High levels of the S100 calcium binding protein S100A4 also called fibroblast specific protein 1 (FSP1) have been established as an inducer of metastasis and indicator of poor prognosis in breast cancer. The mechanism by which S100A4 leads to increased cancer aggressiveness has yet to be established; moreover, the function of this protein in normal mammary gland biology has not been investigated. To address the role of S100A4 in normal mammary gland, its spatial and temporal expression patterns and possible function in branching morphogenesis were investigated. We show that the protein is expressed mainly in cells of the stromal compartment of adult humans, and during active ductal development, in pregnancy and in involution of mouse mammary gland. In 3D culture models, topical addition of S100A4 induced a significant increase in the TGFα mediated branching phenotype and a concomitant increase in expression of a previously identified branching morphogen, metalloproteinase-3 (MMP-3). These events were found to be dependent on MEK activation. Downregulation of S100A4 using shRNA significantly reduced TGFα induced branching and altered E-cadherin localization. These findings provide evidence that S100A4 is developmentally regulated and that it plays a functional role in mammary gland development, in concert with TGFα by activating MMP-3, and increasing invasion into the fat pad during branching. We suggest that S100A4-mediated effects during branching morphogenesis provide a plausible mechanism for how it may function in breast cancer progression. 相似文献