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81.
82.
Kaidong Ma Hong Jin Rong Hu Yu Xiong Shufeng Zhou Peng Ting Yan Cheng Yan Yang Pengyuan Yang Xiaotian Li 《Cell biochemistry and biophysics》2014,69(2):247-258
To explore the proteomic changes of placental trophoblastic cells in preeclampsia–eclampsia (PE), placental trophoblastic cells from normally pregnant women and women with hypertension during gestational period were prepared by laser capture microdissection (LCM), and proteins isolated from these cells were subjected to labeling and proteolysis with isotope-coded affinity tag reagent. A qualitative and quantitative analysis of the proteome expression of placental trophoblastic cells was made using two-dimensional liquid chromatography tandem mass spectrometry (2D LC–MS/MS). A total of 831 proteins in placental trophoblastic cells were identified by combined use of LCM technique and 2D LC–MS/MS. The result was superior to that of conventional two-dimensional electrophoresis method. There were marked differences in 169 proteins of placental trophoblastic cells between normally pregnant women and women with PE. Of 70 (41.4 %) proteins with more than twofold differences, 31 proteins were down-regulated, and 39 were up-regulated in placental trophoblastic cells of the woman with PE. Laminin expression in placenta trophoblastic cells of women with PE was significantly down-regulated as confirmed by Western blot analysis. These findings provide insights into the proteomic changes in placental trophoblastic cells in response to PE and may identify novel protein targets associated with the pathogenesis of PE. 相似文献
83.
84.
Rongzhong Huang Hongchang Gao Lihua Ma Xiao Wang Jianmin Jia Mingju Wang Liang Zhang Xia Liu Peng Zheng Liu Yang Lei Yang Li Dan Xie Peng 《Metabolomics : Official journal of the Metabolomic Society》2014,10(1):33-41
Herpes simplex virus type 1 (HSV-1) is a large, neurotropic, double-stranded DNA virus that establishes a lifelong latent infection in neurons and glial cells. Previous studies reveal that several metabolic perturbations are associated with HSV-1 infection. However, the extracellular metabolic alterations associated with HSV-1 infection have not been systematically profiled in human cells. Here, a proton nuclear magnetic resonance-based metabonomic approach was applied to differentiate the extracellular metabonomic profiles of HSV-1 infected human oligodendroglia cells (n = 18) and matched control cells (n = 18) at three time points (12, 24, and 36 h post-infection). Resulting spectra were analyzed by chemometric and statistical methods. Metabonomic profiling revealed perturbations in 21 extracellular metabolites. Partial least squares discriminant analysis demonstrated that the whole metabolic patterns enabled statistical discrimination between HSV-1 infected human oligodendroglia cells and control cells. Eight extracellular metabolites, seven of which were amino acids, were primarily responsible for score plot discrimination between HSV-1 infected human oligodendroglia cells and control cells at 36 h post-infection: alanine, glycine, isoleucine, leucine, glutamate, glutamine, histidine, and lactate. HSV-1 infection alters amino acid metabolism in human oligodendroglia cells cultured in vitro. HSV-1 infection may disturb these host cellular pathways to support viral replication. Through elucidating the extracellular metabolic changes incident to HSV-1 infection, this study also provides future directions for investigation into the pathogenic mechanism of HSV-1. 相似文献
85.
The moose (Alces alces cameloides) population in northeastern China is on the southernmost edge of its distribution in Asia. A survey was conducted to determine
moose resource selection and the effects of human disturbance on moose in a study area of 20,661 ha located on the northwestern
slope of the Lesser Khingan Mountains, located in northeastern China. Predictive models of resource selection were developed
using logistic and autologistic regression. All models considered resource variable selection at two spatial scales, patch
and landscape. At the patch scale, moose preferred larger birch (Betula platyphylla) patches, but avoided larger tamarack (Larix gmelinii) patches. At the landscape scale, moose preferred higher densities of tamarack patches, i.e., heterogeneity of tamarack stands,
selected areas with more abundant annual shoots, terrain conducive to better concealment, higher altitudes and areas saturated
with soil moisture. Roads and forest harvest intervals were identified as important human disturbance factors. This is the
first time that moose have been reported to avoid roads, and the avoidance distance was nearly 3 km. We believe that in this
region moose under the influence of roads are behaviorally plastic, compared with the indifference of moose to the presence
of roads in other regions. Moose avoided forest areas logged more than 3 years previously and preferred areas logged 1–2 years
previously. In addition, it may be necessary to monitor the effect of the dynamic of density of roe deer on the spatial distribution
of the moose population. 相似文献
86.
Belén Román Ana Ma Torres Diego Rubiales Jose Ignacio Cubero Zlatko Satovic 《Génome》2002,45(6):1057-1063
Orobanche crenata Forsk. is a root parasite that produces devastating effects on many crop legumes and has become a limiting factor for faba bean production in the Mediterranean region. The efficacy of available control methods is minimal and breeding for broomrape resistance remains the most promising method of control. Resistance seems to be scarce and complex in nature, being a quantitative characteristic difficult to manage in breeding programmes. To identify and map the QTLs (quantitative trait loci) controlling the trait, 196 F2 plants derived from the cross between a susceptible and a resistant parent were analysed using isozymes, RAPD, seed protein genes, and microsatellites. F2-derived F3 lines were studied for broomrape resistance under field conditions. Of the 130 marker loci segregating in the F2 population, 121 could be mapped into 16 linkage groups. Simple interval mapping (SIM) and composite interval mapping (CIM) were performed using QTL Cartographer. Composite interval mapping using the maximum number of markers as cofactors was clearly the most efficient way to locate putative QTLs. Three QTLs for broomrape resistance were detected. One of the three QTLs explained more than 35% of the phenotypic variance, whereas the others accounted for 11.2 and 25.5%, respectively. This result suggests that broomrape resistance in faba bean can be considered a polygenic trait with major effects of a few single genes. 相似文献
87.
Milena Sedliaková Viera Slezáriková Jela Brozmanová František Mašek Viktória Bayerová 《Mutation research》1980,71(1):15-23
3 wild-type strains of E. coli, namely K12 AB2497, B/r WP2 and 15 555-7v proficient in excision and post-replication repair, differ markedly in their UV resistance. To elucidate this difference, the influence was investigated of induction by application of inducing fluence (IF) before lethal fluence (LF) on repair processes after LF. In cells distinguished by low UV resistance (E. coli 15 555-7; E. coli B/r WP2), dimer excision was less complete in cultures irradiated with IF + LF than in cultures irradiated with LF only. The highly resistant E. coli K12 AB2497 performed complete excision both after IF + LF or after LF alone. All 3 types of cell survived better after IF + LF than after LF only. Because, in most strains so far investigated, the application of IF reduced dimer excision and increased survival, dimer excision per se does not appear important for survival.We conclude that the rate and completeness of dimer excision can serve as a measure of efficiency of the excision system whose action is necessary for repair of another lesion. Cells of all investigated strains could not resume DNA replication and died progressively when irradiated with LF and post-incubated with chloramphenicol (LF CAP+). Thus, it appears that inducible proteins are necessary for repair in all wild-type E. coli cells give with potentially lethal doses of UV irradiation. 相似文献
88.
89.
Ying Zhang Jing Hu Hong-Jun Lu Jian-Ping Li Ning Wang Wei-Wei Li Yong-Chun Zhou Jun-Yue Liu Sheng-Jun Wang Jing Wang Xia Li Wan-Ling Ma Li-Chun Wei Mei Shi 《PloS one》2013,8(11)
Purpose
To determine the optimal standardized uptake value (SUV) of 18F-fluorodeoxyglucose (18F-FDG) for positron emission tomography (PET) imaging, at which the PET-defined gross tumor volume (GTVPET) best matches with the pathological volume (GTVPATH) in the cervical cancer.Materials and Methods
Ten patients with the cervical cancer who underwent surgery were enrolled in this study. The excised specimens were processed for whole-mount serial sections and H-E staining. The tumor borders were outlined in sections under a microscope, histopathological images were scanned and the GTVPATH calculated. The GTVPET was delineated automatically by using various percentages relative to the maximal SUV and absolute SUV. The optimal threshold SUV was further obtained as the value at which the GTVPET best matched with the GTVPATH.Results
An average of 85±10% shrinkage of tissue was observed after the formalin fixation. The GTVPATH was 13.38±2.80 cm3 on average. The optimal threshold on percentile SUV and absolute SUV were 40.50%±3.16% and 7.45±1.10, respectively. The correlation analysis showed that the optimal percentile SUV threshold was inversely correlated with GTVPATH (p<0.05) and tumor diameter (p<0.05). The absolute SUV was also positively correlated with SUVmax (p<0.05).Conclusion
The pathological volume could provide the more accurate tumor volume. The optimal SUV of FDG for PET imaging by use of GTVPATH as standard for cervical cancer target volume delineation was thus determined in this study, and more cases are being evaluated to substantiate this conclusion. 相似文献90.
Jiayi Tong Jiandong Ding Xiangbo Shen Long Chen Yeping Bian Genshan Ma Yuyu Yao Fang Yang 《PloS one》2013,8(11)