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101.
Yin Chun-yu Lu Hong-zhou Jiang Wei-ming Maria Pia De Pasquale Hu Yue-kai Pan Xiao-zhang Weng Xin-hua Richard T. D’Aquila Tang Yi-Wei 《中国病毒学》2007,22(3):212-217
Illegally paid blood donation was a risk factor for HIV acquisition exclusively in Henan and Hubei Provinces of China, and
not in Shanghai. Nucleotide sequences in the gag and env genes of HIV-1 were compared between isolates from Henan and Shanghai regions of China to test whether an expected higher
degree of a common source of infections from this unique blood donation transmission risk would be evident as decreased variation
among Henan isolates in an exploratory cross-sectional analysis. Among 38 isolates studied, 23 of 23 (100%) from Henan and
8 of 15 (54%) from Shanghai were subtype B. In addition, fewer sequence differences were found in gp41 of subtype B isolates
from Henan than from Shanghai isolates. Further studies with additional controls are therefore warranted to confirm the role
of the degree of a common source of infections in differences in HIV variation across populations.
Fundation items: The Vanderbilt-Meharry Center for AIDS Research (P30 AI 54999); R.T.D (R01 AI 29193); Start Fund of Ministry
of Education of China (for Hong-zhou LU, 2004BA719A10). 相似文献
102.
Stem cell aging is controlled both intrinsically and extrinsically in the Drosophila ovary 总被引:2,自引:0,他引:2
It is widely postulated that tissue aging could be, at least partially, caused by reduction of stem cell number, activity, or both. However, the mechanisms of controlling stem cell aging remain largely a mystery. Here, we use Drosophila ovarian germline stem cells (GSCs) as a model to demonstrate that age-dependent decline in the functions of stem cells and their niche contributes to overall stem cell aging. BMP signaling activity from the niche significantly decreases with age, and increasing BMP signaling can prolong GSC life span and promote their proliferation. In addition, the age-dependent E-cadherin decline in the stem cell-niche junction also contributes to stem cell aging. Finally, overexpression of SOD, an enzyme that helps eliminate free oxygen species, in either GSCs or their niche alone can prolong GSC life span and increase GSC proliferation. Therefore, this study demonstrates that stem cell aging is controlled extrinsically and intrinsically in the Drosophila ovary. 相似文献
103.
Bo Sun Yiming Li Yiming Zhou Tien Khee Ng Chao Zhao Qiaoqiang Gan Xiaodong Gu Jianbin Xiang 《Journal of cellular physiology》2019,234(2):1416-1425
Exosomal proteins are emerging as relevant diagnostic and prognostic biomarkers for cancer. This study was aimed at illustrating the clinical significance of exosomal Copine III (CPNE3) purified from the plasma of colorectal cancer (CRC) patients. The CPNE3 expression levels in CRC tissues were analyzed by real-time PCR, western blot, and immunohistochemistry. Plasma exosomes were isolated to examine the CPNE3 level using ELISA. Pearson’s correlation analysis was performed to investigate the CPNE3 levels between CRC tissues and matched plasma samples. Receiver operating characteristic curve analysis was developed to measure the diagnostic performance of exosomal CPNE3. The Kaplan–Meier method and Cox's proportional hazards model were utilized to determine statistical differences in survival times. CPNE3 showed increased expressions in the CRC tissues. A moderately significant correlation was found between CPNE3 expression in CRC tissues by immunohistochemistry and matched serum exosomal CPNE3 expression by ELISA (r = 0.645,(r = 0.645, p < 0.001). < 0.001). Exosomal CPNE3 yielded a sensitivity of 67.5% and a specificity of 84.4% in CRC at the cutoff value of 0.143 pg per 1ug1 ug exosome. Combined data from carcinoembryonic antigen and exosomal CPNE3 achieved 84.8% sensitivity and 81.2% specificity as a diagnostic tool. CRC patients with lower exosomal CPNE3 levels had substantially better disease-free survival (hazard ratio [HR], 2.9; 95% confidence interval [CI]: 1.3–6.4; p = 0.009) = 0.009) and overall survival (HR, 3.4; 95% CI: 1.2–9.9; p = 0.026) = 0.026) compared with those with higher exosomal CPNE3 levels. Exosomal CPNE3 show potential implications in CRC diagnosis and prognosis. 相似文献
104.
Guan Wang Zong-Jian Liu Xuan Liu Feng-Ge Liu Yan Li Yi-Bing Weng Jian-Xin Zhou 《Journal of cellular physiology》2019,234(11):20118-20127
This study aims to determine the feasibility of using oligodeoxynucleotides with unmethylated cytosine-guanine dinucleotide sequences (CpG ODN) as an immunity protection strategy for a mouse model of acute respiratory distress syndrome (ARDS). This is a prospective laboratory animal investigation. Twenty-week-old BALB/c mice in Animal research laboratory were randomized into groups. An ARDS model was induced in mice using lipopolysaccharides (LPSs). CpG ODN was intranasally and transrectally immunized before or after the 3rd and 7th days of establishing the ARDS model. Mice were euthanized on Day 7 after the second immunization. Then, retroorbital bleeding was carried out and the chest was rapidly opened to collect the trachea and tissues from both lungs for testing. CpG ODN significantly improved the pathologic impairment in mice lung, especially after the intranasal administration of 50 μg. This resulted in the least severe lung tissue injury. Furthermore, interleukin-6 (IL-6) and IL-8 concentrations were lower, which was second to mice treated with the rectal administration of 20 µg CpG ODN. In contrast, the nasal and rectal administration of CpG ODN in BALB/c mice before LPS immunization did not appear to exhibit any significant protective effects. The intranasal administration of CpG ODN may be a potential treatment approach to ARDS. More studies are needed to further determine the protective mechanism of CpG ODN. 相似文献
105.
Claassens Anders Rose Michael T. Van Zwieten Lukas Weng Zhe Rose Terry J. 《Plant and Soil》2019,439(1-2):393-404
Plant and Soil - Some studies have shown that an increasing atmospheric CO2 concentration reduces plant transpiration while others have demonstrated that it interacts with nutrients in soil to... 相似文献
106.
107.
Journal of Insect Behavior - Honey bees have three castes, drones, workers, and queens, that accomplish different tasks. In this research, we revealed the divergence in feeding behavior of drones... 相似文献
108.
109.
110.
Hong Liu Jiahui Liu Lei Si Cunju Guo Wei Liu Yiming Liu 《Journal of cellular biochemistry》2019,120(6):10530-10547
The neuronal cell line HT22 is an excellent model for studying Parkinson's disease. Growth differentiation factor 15 (GDF15) plays a critical role in Parkinson's disease, but the molecular mechanism involved are not well understood. We constructed the GDF15 overexpression HT22 cells and detected the effects of overexpression of GDF15 on the viability, oxygen consumption, mitochondrial membrane potential of oligomycin-treated HT22 cells. In addition, we used a high-throughput RNA-sequencing to study the lncRNA and mRNA expression profiling and obtained key lncRNAs, mRNA, gene ontology (GO), and Kyoto encyclopedia of genes and genomes (KEGG) pathway. The expression of selected DElncRNAs was validated by quantitative real-time PCR (qRT-PCR). Our results showed that overexpression of GDF15 significantly reversed the cells viability, oxygen consumption, and mitochondrial membrane potential effect caused by oligomycin in HT22 cells. The 1093 DEmRNAs and 395 DElncRNAs in HT22 cells between GDF15-oligomycin non-intervention group and a normal control-oligomycin un-intervention group were obtained, and 394 DEmRNAs and 271 DElncRNAs in HT22 cells between GDF15-oligomycin intervention group and normal control-oligomycin intervention group were identified. Base on the GO and KEGG enrichment analysis of between GDF15-oligomycin intervention group and normal control-oligomycin intervention group, positive regulation of cell proliferation was most significantly enriched GO terms, and Cav1 was enriched in positive regulation of cell proliferation pathway. PI3K-Akt signaling pathway was one significantly enriched pathway in GDF15-oligomycin intervention group. The qRT-PCR results were consistent with RNA-sequencing, generally. GDF15 might promote mitochondrial function and proliferation of HT22 cells by regulating PI3K/Akt signaling pathway. Our study may be helpful in understanding the potential molecular mechanism of GDF15 in Parkinson's disease. 相似文献