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81.
Development of transportation infrastructure that extends roads and railways in Bangkok has overlooked the negative environmental impact of construction material accumulation. To analyze the extent of this impact, we originally established road and railway's material intensity coefficients and investigated spatially explicit roadway and railway material stock (MS) for the years of 2004, 2009, 2014, 2019, and 2037, based upon the master plans’ target year. We further analyzed how MS evolution relates to the city's socio-economic indicators and CO2 emission. Significant growth is found in transportation MS during 2004–2019, and roadways particularly increased from 122 to 164 million metric tons (Mt). The master plans would require 43 and 6.55 Mt construction materials for roadway and railway extension, respectively, by 2037. More material-intensive roads (cross-provincial highways and major local roads) built to the suburbs of the cities and underground/elevated structures of the mass rapid transit system in dense urban areas will require three times the annual cement and steel consumption of that in the 2004–2019 period. Furthermore, a 2–3 fold increase in the number of registered vehicles and associated CO2 emissions during the study period have brought questions to the transportation infrastructure MS efficiency. The findings of this study will enable informed decision-making regarding the concern of resource consumption and for considering environmentally friendly approaches in urban transportation planning for Bangkok and other developing cities.  相似文献   
82.
China is the largest producer and consumer of cement worldwide, and cement production entails the release of substantial carbon dioxide (CO2) emissions. As the cement sector is a crucial sector of the Chinese economy, understanding the role of supply‐ and demand‐side factors may help accelerate efforts to mitigate CO2 emissions. However, few studies have analyzed the critical factors affecting CO2 emissions in the sector based on a combined supply‐ and demand‐side perspective. In this study, we developed an integrated framework that included eleven indicators covering both the supply and demand sides. Results revealed that improving cement production technology cannot offset CO2 emissions from the growth in demand for cement. Improving technology on the supply side would considerably reduce CO2 emissions from Chinese cement production; nevertheless, the combination of rapid urbanization, GDP growth, and an ultra‐high fixed capital formation ratio on the demand side increased CO2 emissions nearly 25‐fold from 1990 to 2015. Notably, some demand‐side factors also had an effect that reduced CO2 emissions. The in‐use stock per unit of fixed capital formation and output per in‐use stock reduced CO2 emissions by 332 million metric tons, which is comparable to the contribution of technological progress. Based on these results, we examine why these demand‐side factors substantially influence CO2 emissions in the Chinese cement sector, and we provide recommendations for policy‐makers on carbon‐reduction measures in this CO2‐intensive sector.  相似文献   
83.
Tanikawa  Toko  Ikeno  Hidetoshi  Yamase  Keitaro  Dannoura  Masako  Aono  Kenji  Hirano  Yasuhiro 《Plant and Soil》2021,466(1-2):239-256
Plant and Soil - Root hemiparasite infection is considered a potential biotic stress that affects the growth of cool-season grasses, and the damage caused by a hemiparasitic plant to host grasses...  相似文献   
84.
Peptic ulcer is one of the most common gastrointestinal disorders with complex etiology. Recently we conducted the genome wide association study for duodenal ulcer and identified disease susceptibility variations at two genetic loci corresponding to the Prostate stem cell antigen (PSCA) gene and the ABO blood group (ABO) gene. Here we investigated the association of these variations with gastric ulcer in two Japanese case-control sample sets, a total of 4,291 gastric ulcer cases and 22,665 controls. As a result, a C-allele of rs2294008 at PSCA increased the risk of gastric ulcer with odds ratio (OR) of 1.13 (P value of 5.85×10−7) in an additive model. On the other hand, SNP rs505922 on ABO exhibited inconsistent result between two cohorts. Our finding implies presence of the common genetic variant in the pathogenesis of gastric and duodenal ulcers.  相似文献   
85.
We collected 24 brown rats, Rattus norvegicus, in Kanagawa Prefecture in Japan and found one rat harboring a dioctophymatid nematode. A single male and a female worm were recovered from the abdominal cavity and were identified as Dioctophyme renale based on morphologic features and a BLAST DNA sequence analysis. We describe the morphological features of the adult worms and eggs from this extremely rare case of D. renale infection in a brown rat.  相似文献   
86.
Ye R  Wang W  Iki T  Liu C  Wu Y  Ishikawa M  Zhou X  Qi Y 《Molecular cell》2012,46(6):859-870
In plants, DNA methylation can be mediated by a class of Argonaute4 (AGO4)-associated heterochromatic siRNAs (hc-siRNAs), through a pathway termed RNA-directed DNA methylation (RdDM). It has been thought that RdDM is solely a nuclear process, as both the biogenesis and functioning of hc-siRNAs take place in the nucleus. In this study, we unexpectedly found that hc-siRNAs are predominantly present in the cytoplasm. We demonstrated that AGO4 is loaded with hc-siRNAs in the cytoplasm and the formation of mature AGO4/siRNA complexes requires HSP90 and the cleavage activity of AGO4. Intriguingly, siRNA binding facilitates the redistribution of AGO4 into the nucleus, likely through inducing conformational change that leads to the exposure of the nuclear localization signal (NLS). Our findings reveal an unsuspected cytoplasmic step in the RdDM pathway. We propose that selective nuclear import of mature AGO4/siRNA complexes is a key regulatory point prior to the effector stage of RdDM.  相似文献   
87.
The authors recorded cerebral-evoked responses elicited by direct stimulation of the human lateral spinothalamic tract (LST) during percutaneous cordotomy to investigate central conduction of noxious stimuli. These responses consisted of four negative potentials, peak latency being 3.8 (N1), 8.4 (N2), 12.2 (N3) and 21.9 (N4) ms respectively. N1 showed wide distribution over the scalp and was considered to be of subcortical origin. N2-N4 were distributed in both the temporal and central area. The different distribution pattern of N2-N4 from conventional somatosensory-evoked potential suggested a different projection of LST from the medial lemniscus system.  相似文献   
88.
Serum amyloid A-induced IL-6 production by rheumatoid synoviocytes   总被引:1,自引:0,他引:1  
In this study, we investigated the role of serum amyloid A protein (SAA) in the production of interleukin-6 (IL-6) using rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS). Recombinant SAA stimulation induced the production of pro-inflammatory cytokine, IL-6, from RA-FLS. The signaling events induced by SAA included the activation of the mitogen-activated protein kineases, p38 and JNK1/2 and the activation of nuclear factor-kappa B (NF-kappaB). Inhibitor studies have shown SAA-induced IL-6 production to be down-regulated by NF-kappaB inhibition and partially inhibited by p38 or JNK inhibitors. Our findings demonstrate that SAA is a significant inducer of IL-6, which is critically involved in RA pathogenesis.  相似文献   
89.
Three ethylene receptor genes, DC-ERS1, DC-ERS2 and DC-ETR1, were previously identified in carnation (Dianthus caryophyllus L.). Here, the presence of mRNAs for respective genes in flower tissues and their changes during flower senescence are investigated by Northern blot analysis. DC-ERS2 and DC-ETR1 mRNAs were present in considerable amounts in petals, ovaries and styles of the flower at the full-opening stage. In the petals the level of DC-ERS2 mRNA showed a decreasing trend toward the late stage of flower senescence, whereas it increased slightly in ovaries and was unchanged in styles throughout the senescence period. However, DC-ETR1 mRNA showed no or little changes in any of the tissues during senescence. Exogenously applied ethylene did not affect the levels of DC-ERS2 and DC-ETR1 mRNAs in petals. Ethylene production in the flowers was blocked by treatment with 1,1-dimethyl-4-(phenylsulphonyl)semicarbazide (DPSS), but the mRNA levels for DC-ERS2 and DC-ETR1 decreased in the petals. DC-ERS1 mRNA was not detected in any cases. These results indicate that DC-ERS2 and DC-ETR1 are ethylene receptor genes responsible for ethylene perception and that their expression is regulated in a tissue-specific manner and independently of ethylene in carnation flowers during senescence.  相似文献   
90.
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