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Reactive oxygen species have various effects on the expression of cell adhesion molecules induced by pro-inflammatory cytokines, such as tumor necrosis factor f (TNF- f ). We studied the effects of monochloramine (NH 2 Cl), a physiological oxidant derived from activated neutrophils, on the TNF- f -induced expression of e-selectin and intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVEC). HUVEC were pretreated with or without NH 2 Cl (20-90 w M for 20 min), then stimulated with TNF- f (10 ng/ml), and the expression of e-selectin and ICAM-1 was measured. Without NH 2 Cl, TNF- f induced marked expression of e-selectin and ICAM-1. Pretreatment with NH 2 Cl resulted in a significant, but transient inhibition of the expression of adhesion molecules. Higher dose of NH 2 Cl showed more pronounced inhibition, and the inhibitory effect lasted for 8 h when 70 w M of NH 2 Cl was added. TNF- f stimulation also induced marked activation of nuclear factor s B (NF- s B). Notably, NH 2 Cl also inhibited this NF- s B activation in a dose- and time-dependent manner, which was similar to the inhibition of e-selectin and ICAM-1 expression. In addition, I s B- f phosphorylation and degradation were also inhibited by NH 2 Cl pretreatment. These observations indicated that NH 2 Cl inhibited TNF- f -induced expression of e-selectin and ICAM-1 through the inhibition of NF- s B activation. We speculate that neutrophil-derived chloramines may have a regulatory role in the recruitment of leukocytes. 相似文献
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Muhammad Shahid Iqbal Aung Tin Abdul Mian Akram Ali James OHara Josef Kovarik Rahul Patil Eleanor Aynsley Charles Kelly 《Reports of Practical Oncology and Radiotherapy》2022,27(3):401
BackgroundNasopharyngeal carcinoma (NPC) is rare in the UK. The aim of the current study was to investigate survival outcomes for patients with NPC treated with (chemo)radiotherapy using 65 Gy in 30 fractions in a non-endemic region.Materials and methodsAll consecutive 62 patients with histology proven non-metastatic nasopharyngeal carcinoma diagnosed between January 2009 to June 2019 were included in this retrospective analysis.ResultsMedian age was 59 years (range:19–81). The majority of patients had stage III disease (66.1%). Induction chemotherapy was given in 21% of patients and 82.3% of patients received concomitant systemic therapy. All patients were treated with 65 Gy in 30 fractions. There was disease recurrence in 17.4% patients. The 5-year disease-free, disease-specific and overall survival were 81.9%, 79.2% and 76.4%, respectively. On univariate analysis, disease recurrence was associated with N-stage (p = 0.047) and overall stage group (p = 0.023).ConclusionTo the best of authors’ knowledge, this is the first report of the use of 65 Gy in 30 fractions of radiotherapy ± weekly cisplatin chemotherapy in NPC in a real-world setting. Our results are comparable to that from other non-endemic regions of the world using different dose fractionation of (chemo)radiotherapy. Future randomised control trials are warranted to compare various dose fractionations in these settings. 相似文献
64.
Win S Than TA Han D Petrovic LM Kaplowitz N 《The Journal of biological chemistry》2011,286(40):35071-35078
Sustained JNK activation plays a critical role in hepatotoxicity by acetaminophen or GalN/TNF-α. To address the importance of JNK translocation to mitochondria that accompanies sustained activation in these models, we assessed the importance of the expression of a potential initial target of JNK in the outer membrane of mitochondria, namely Sab (SH3 domain-binding protein that preferentially associates with Btk), also known as Sh3bp5 (SH3 domain-binding protein 5). Silencing the expression of Sab in the liver using adenoviral shRNA inhibited sustained JNK activation and mitochondrial targeting of JNK and the upstream MKK4 (MAPK kinase 4), accompanied by striking protection against liver injury in vivo and in cultured hepatocytes in both toxicity models. We conclude that mitochondrial Sab may serve as a platform for the MAPK pathway enzymes and that the interaction of stress-activated JNK with Sab is required for sustained JNK activation and toxicity. 相似文献
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Shiau CY Pong YP Chiou TK Tin YY 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,128(3):501-506
Milkfish (Chanos chanos) decreased their body weight from 47 to 28 g over the 60-day period of starvation. Starvation also resulted in the reduction of muscle lipid and protein, and hepatosomatic index. The predominant free amino acid (FAA) in white muscle of milkfish was histidine, followed by taurine and glycine. In the first 25 days of starvation, no significant change in histidine was found. After 40 days of starvation, however, the histidine concentration was significantly decreased by 46%, and remained unchanged thereafter. As compared to control group fish, the 60-day-starved fish possessed only half the amount of histidine. Taurine and glycine, on the other hand, showed no significant changes throughout starvation. Taurine became the most predominant in the FAA pool after 40 days of starvation, and the concentration of 60-day-starved fish was two times higher than that of control group fish without starvation. The ratios of histidine, taurine, and glycine to total FAAs remained approximately the same although the individual contributions varied considerably to the total FAAs during starvation. The results of this study suggested that a good strategy would be to keep taurine and glycine in milkfish muscle at relatively high levels for physiological function as histidine decreased drastically for energy source under conditions of food deprivation. 相似文献
67.
The comparative leaf anatomy of Goniothamus andersonii, G. macrophyllus, G. malayanus and G. velutinus 总被引:2,自引:0,他引:2
G. BLUNDEN AYE KYI K. JEWERS 《Botanical journal of the Linnean Society. Linnean Society of London》1973,67(4):361-376
The leaf anatomy of Goniothalamus andersonii, G. macrophyllus, G. malayanus and G. velutinus from the peat swamps of Sarawak is compared. Sufficient anatomical differences exist to differentiate the four species. G. velutinus has many points of difference from the other three species and G. macrophyllus is readily identified by the presence of fibre-sclereids in the lamina mesophyll. G. andersonii and G. malayanus are similar to each other, but G. andersonii can be distinguished, in particular by the more pronounced multiple projections of the outer periclinal walls of the epidermal cells and the presence of thick and cutinised outer ends of the anticlinal walls of the epidermal cells. 相似文献
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Holowaty MN Sheng Y Nguyen T Arrowsmith C Frappier L 《The Journal of biological chemistry》2003,278(48):47753-47761
USP7 or HAUSP is a ubiquitin-specific protease in human cells that regulates the turnover of p53 and is bound by at least two viral proteins, the ICP0 protein of herpes simplex type 1 and the EBNA1 protein of Epstein-Barr virus. We have overexpressed and purified USP7 and shown that the purified protein is monomeric and is active for cleaving both a linear ubiquitin substrate and conjugated ubiquitin on EBNA1. Using partial proteolysis of USP7 coupled with matrix-assisted laser desorption ionization time-of-flight mass spectrometry, we showed that USP7 comprises four structural domains; an N-terminal domain known to bind p53, a catalytic domain, and two C-terminal domains. By passing a mixture of USP7 domains over EBNA1 and ICP0 affinity columns, we showed that the N-terminal p53 binding domain was also responsible for the EBNA1 interaction, while the ICP0 binding domain mapped to a C-terminal domain between amino acids 599-801. Tryptophan fluorescence assays showed that an EBNA1 peptide mapping to residues 395-450 was sufficient to bind the USP7 N-terminal domain and did so with a dissociation constant of 0.9-2 microM, whereas p53 peptides spanning the USP7-binding region gave dissociation constants of 9-17 microM in the same assay. In keeping with these relative affinities, gel filtration analyses of the complexes showed that the EBNA1 peptide efficiently competed with the p53 peptide for USP7 binding, suggesting that EBNA1 could affect p53 function in vivo by competing for USP7. 相似文献
70.