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91.
Díaz-Gil JJ García-Monzón C Rúa C Martín-Sanz P Cereceda RM Miquilena-Colina ME Machín C Fernández-Martínez A García-Cañero R 《Histology and histopathology》2008,23(5):583-591
Liver growth factor (LGF), a mitogen for liver cells, behaves as an anti-fibrotic agent even in extrahepatic sites, but its mechanistic basis is unknown. We aimed to determine the intrahepatic expression pattern of key modulators of liver fibrosis in bile duct-ligated rats (BDL) after injection of LGF. BDL rats received either LGF (4.5 microg/ratXdose, two doses/week, at time 0 or 2 or 5w after operation, depending on the group (BDL+LGF groups, n=20) or saline (BDL+S groups, n=20). Groups were compared in terms of fibrosis (histomorphometry), liver function (aminopyrine breath test), matrix metalloproteinases MMP-2 and MMP-9, transforming growth factor beta 1 (TGF-beta1) and liver endoglin content (Western blotting), and serum tissue inhibitor of metalloproteinases 1 (TIMP-1) levels (ELISA). In BDL+LGF rats, the fibrotic index was significantly lower at 5w, p=0.006, and at 8w, p=0.04, than in BDL+S rats. Liver function values in BDL+LGF rats were higher than those obtained in BDL+S rats (80% at 5w and 79% at 8w, versus 38% and 29%, p<0.01, taking healthy controls as 100%). Notably, in BDL+LGF rats the intrahepatic expression levels of both MMPs were lower at 2w (MMP-2, p=0.03; MMP-9, p=0.05) and 5w (MMP-2, p=0.05, MMP-9, p=0.04). In addition, the hepatic TGF-beta1 level in BDL+LGF rats was lower at 2w (36%, p=0.008), 5w (50%) and 8wk (37%), whereas intrahepatic endoglin expression remained constant in all BDL rats studied. LGF ameliorates liver fibrosis and improves liver function in BDL rats. The LGF-induced anti-fibrotic effect is associated with a decreased hepatic level of MMP-2, MMP-9 and TGF-beta1 in fibrotic rats. 相似文献
92.
93.
Bleomycin (BLM) induces DNA damage in living cells. In this report we analyzed the role of chromatin compactness in the differential response of mosquito (ATC-15) and mammalian (CHO) cells to DNA strand breaks induced by BLM. We used cells unexposed and exposed to sodium butyrate (NaB), which induces chromatin decondensation. By nucleoid sedimentation assay and digestions of nuclei with DNAse I, untreated mosquito cells (no BLM; no NaB) were shown to have more chromatin condensation than untreated CHO cells. By alkaline unwinding ATC-15 cells treated with NaB showed more BLM-induced DNA strand breaks than NaB-untreated CHO cells. The time-course of BLM-induced DNA damage to nuclear DNA was similar for NaB-untreated mammalian and insect cells, but with mosquito cells showing less DNA strand breaks, both at physiological temperatures and at 4 °C. However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells. 相似文献
94.
Peatlands, with organic soils, are usually dominated by one or a few species. Above and belowground ecological processes are regulated by the characteristics of the dominant species in the peat. Understanding how these species relate to climatic or water chemistry gradients will help to predict the fate of those ecosystems under current climate change. The patterns of abundance and occurrence of 12 major peat-forming species from different structural plant groups were quantified along gradients of elevation, precipitation, and water chemistry. The species were distributed in four major structural groups: cushion plants, true mosses, sedges, and Sphagnum mosses. A response curve for each species was built with Generalized Additive Models. Niche breadths, species tolerances, and species optima were estimated using bootstrap resampling. Our results showed that species were limited in their elevational ranges; Sphagnum species were biased toward low to intermediate elevations, sedges, and true mosses to intermediate elevations and cushion plants to very high elevations. Sphagnum species were more likely to occur in sites with low precipitation, while sedges preferred wet sites. Sphagnum species preferred habitats with acidic pH. The species tolerances and optimum distributions are an indication to the vulnerability of the species to changes in their environment. Species with limited tolerances are more vulnerable, such as the narrow elevational distribution of cushion plants or the low pH and narrow tolerances observed for Sphagnum species. Climate and hydrological changes will very possibly affect the distribution of those species forcing changes on ecosystem functioning. 相似文献
95.
Yao Shi Juan Yuan Vilma Rraklli Eva Maxymovitz Miriam Cipullo Mingzhi Liu Shuijie Li Isabelle Westerlund Oscar C Bedoya-Reina Petra Bullova Joanna Rorbach C Christofer Juhlin Adam Stenman Catharina Larsson Per Kogner Maureen J OSullivan Susanne Schlisio Johan Holmberg 《Nucleic acids research》2021,49(5):2509
96.
Wenjuan Dong Heather Mead Lei Tian Jun-Gyu Park Juan I. Garcia Sierra Jaramillo Tasha Barr Daniel S. Kollath Vanessa K. Coyne Nathan E. Stone Ashley Jones Jianying Zhang Aimin Li Li-Shu Wang Martha Milanes-Yearsley Jordi B. Torrelles Luis Martinez-Sobrido Paul S. Keim Bridget Marie Barker Michael A. Caligiuri Jianhua Yu 《Journal of virology》2022,96(1)
97.
Treatment of Biogas Produced in Anaerobic Reactors for Domestic Wastewater: Odor Control and Energy/Resource Recovery 总被引:1,自引:0,他引:1
Adalberto Noyola Juan Manuel Morgan-Sagastume Jorge E. López-Hernández 《Reviews in Environmental Science and Biotechnology》2006,5(1):93-114
Anaerobic municipal wastewater treatment in developing countries has important potential applications considering their huge
lack of sanitation infrastructure and their advantageous climatic conditions. At present, among the obstacles that this technology
encounters, odor control and biogas utilization or disposal should be properly addressed. In fact, in most of small and medium
size anaerobic municipal treatment plants, biogas is just vented, transferring pollution from water to the atmosphere, contributing
to the greenhouse gas inventory. Anaerobic municipal sewage treatment should not be considered as an energy producer, unless
a significant wastewater flow is treated. In these cases, more than half of the methane produced is dissolved and lost in
the effluent so yield values will be between 0.08 and 0.18 N m3 CH4/kg COD removed. Diverse technologies for odor control and biogas cleaning are currently available. High pollutant concentrations
may be treated with physical-chemical methods, while biological processes are used mainly for odor control to prevent negative
impacts on the treatment facilities or nearby areas. In general terms, biogas treatment is accomplished by physico-chemical
methods, scrubbing being extensively used for H2S and CO2 removal. However, dilution (venting) has been an extensive disposal method in some small- and medium-size anaerobic plants
treating municipal wastewaters. Simple technologies, such as biofilters, should be developed in order to avoid this practice,
matching with the simplicity of anaerobic wastewater treatment processes. In any case, design and specification of biogas
handling system should consider safety standards. Resource recovery can be added to anaerobic sewage treatment if methane
is used as electron donor for denitrification and nitrogen control purposes. This would result in a reduction of operational
cost and in an additional advantage for the application of anaerobic sewage treatment. In developing countries, biogas conversion
to energy may apply for the clean development mechanism (CDM) of the Kyoto Protocol. This would increase the economic feasibility
of the project through the marketing of certified emission reductions (CERs). 相似文献
98.
1-羟基-2-甲基-2-E-丁烯基-4-焦磷酸还原酶(HDR)是甲基-D-赤藓醇-4-磷酸(MEP)途径中的最后一个酶,在植物萜类生物合成中起主控作用。该研究根据思茅松(Pinus kesiya var.langbianensis)树皮转录组数据分析结果,首先获得了思茅松HDR基因片段,然后根据所获得的基因片段设计特异引物,提取受伤后的思茅松树皮的RNA,并运用RT-PCR和RACE技术从思茅松树皮中克隆得到完整的HDR基因(Pk HDR)。生物信息学分析表明:克隆获得的Pk HDR1基因c DNA全长序列为1 876 bp,含有1个1 464 bp的开放阅读框(ORF),编码487个氨基酸。同源性分析结果表明:思茅松HDR蛋白与赤松(Pinus densiflora)HDR蛋白的相似性高达99%。亚细胞定位及结构域分析结果表明:思茅松Pk HDR氨基酸序列中包含转运肽序列(A1-A61)及植物HDR蛋白多个保守的功能位点(A143,A234,A288,A371)。系统进化分析结果表明:Pk HDR蛋白与赤松HDR蛋白的亲缘关系最为接近。半定量PCR检测结果表明:树皮的创伤促进思茅松HDR基因的表达。该研究成功克隆获得HDR基因,并确定其与松脂代谢密切相关,为阐明思茅松松脂生物合成机制和分子育种提供了参考。 相似文献
99.
Tao Tan Jun Wu Chenyang Si Shaoxing Dai Youyue Zhang Nianqin Sun E Zhang Honglian Shao Wei Si Pengpeng Yang Hong Wang Zhenzhen Chen Ran Zhu Yu Kang Reyna Hernandez-Benitez Llanos Martinez Martinez Estrella Nuñez Delicado W. Travis Berggren Juan Carlos Izpisua Belmonte 《Cell》2021,184(8):2020-2032.e14
100.
A Garcia-Muñoz MA Rodriguez R Bologna-Molina FE Cazares-Raga FC Hernandez-Hernandez JE Farfan-Morales JJ Trujillo C Liceaga-Escalera G Mendoza-Hernandez 《Proteome science》2012,10(1):49
ABSTRACT: BACKGROUND: Odontogenic myxoma (OM) is a benign, but locally invasive, neoplasm occurring in the jaws. However, the molecules implicated in its development are unknown. OM as well as Dental Follicle (DF), an odontogenic tissue surrounding the enamel organ, is derived from ectomesenchymal/mesencyhmal elements. To identify some protein that could participate in the development of this neoplasm, total proteins from OM were separated by two-dimensional electrophoresis and the profiles were compared with those obtained from DF, used as a control. RESULTS: We identified eight proteins with differential expression; two of them were downregulated and six upregulated in OM. A spot consistently overexpressed in odontogenic myxoma, with a molecular weight of 44-kDa and a pI of 3.5 was identified as the orosomucoid 1 protein. Western blot experiments confirmed the overexpression of this protein in odontogenic myxoma and immunohistochemical assays showed that this protein was mainly located in the cytoplasm of stellate and spindle-shaped cells of this neoplasm. CONCLUSION: Orosomucoid 1, which belongs to a group of acute-phase proteins, may play a role in the modulation of the immune system and possibly it influences the development of OM. 相似文献