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101.
摘要 目的:探讨血清淀粉样蛋白A(SAA)、C反应蛋白(CRP)、外周血血小板分布宽度(PDW)及中性粒细胞/淋巴细胞比值(NLR)对新生儿坏死性小肠结肠炎(NEC)手术时机的预测价值。方法:选取2019年1月~2022年1月佛山市妇幼保健院收治的70例NEC患儿,根据治疗方式分为手术组35例和非手术组35例。收集NEC患儿临床资料,并检测两组患儿血清SAA、CRP、外周血PDW及NLR水平。采用单因素、多因素Logistic回归分析新生儿NEC手术的影响因素,受试者工作特征(ROC)曲线分析血清SAA、CRP、外周血PDW及NLR对新生儿NEC手术时机的预测价值。结果:手术组胎龄≥37周、诊断时体重>2500 g比例低于非手术组,诊断时体重1500~2500 g、精神反应差、腹胀、肠鸣音微弱比例和血清SAA、CRP、外周血PDW及NLR水平高于非手术组(均P<0.05)。多因素Logistic回归分析显示,诊断时体重>2500 g为新生儿NEC手术的独立保护因素,精神反应差、腹胀、肠鸣音微弱和血清SAA、CRP、外周血PDW及NLR水平升高为新生儿NEC手术的独立危险因素(均P<0.05)。ROC曲线分析显示,血清SAA、CRP、外周血PDW及NLR联合预测新生儿NEC手术时机的曲线下面积(AUC)大于各项指标单独预测。结论:血清SAA、CRP、外周血PDW及NLR水平升高与新生儿NEC手术密切相关,四项指标联合预测新生儿NEC手术时机的价值较高。 相似文献
102.
Marcin Wasylewski Jedrzej Ma?ecki Zygmunt Wasylewski 《Journal of Protein Chemistry》1995,14(5):299-308
Time-resolved, steady-state fluorescence and fluorescence-detected circular dichroism (FDCD) have been used to resolve the fluorescence contributions of the two tryptophan residues, Trp-13 and Trp-85, in the cyclic AMP receptor protein (CRP). The iodide and acrylamide quenching data show that in CRP one tryptophan residue, Trp-85, is buried within the protein matrix and the other, Trp-13, is moderately exposed on the surface of the protein. Fluorescence-quenching-resolved spectra show that Trp-13 has emission at about 350 nm and contributes 76–83% to the total fluorescence emission. The Trp-85, unquenchable by iodide and acrylamide, has the fluorescence emission at about 337 nm. The time-resolved fluorescence measurements show that Trp-13 has a longer fluorescence decay time. The Trp-85 exhibits a shorter fluorescence decay time. In the CRP-cAMP complex the Trp-85, previously buried in the apoprotein becomes totally exposed to the iodide and acrylamide quenchers. The FDCD spectra indicate that in the CRP-cAMP complex Trp-85 remains in the same environment as in the protein alone. It has been proposed that the binding of cAMP to CRP is accompanied by a hinge reorientation of two protein domains. This allows for penetration of the quencher molecules into the Trp-85 residue previously buried in the protein matrix.Abbreviations CRP
cyclic AMP receptor protein
- NATA
N-acetyltryptophanamide
- FQRS
fluorescence-quenching-resolved spectra
- FDCD
fluorescence-detected circular dichroism
- EDTA
ethylenediaminetetraacetic acid
- SDS
sodium dodecyl sulfate
- FPLC
fast protein liquid chromatography 相似文献
103.
Genetic and physical analysis of the thioredoxin (trxA) gene of Escherichia coli K-12 总被引:8,自引:0,他引:8
The trxA gene of Escherichia coli K-12 has been cloned into multicopy plasmids on DNA fragments of varying sizes. The smallest of these was a 1-kb fragment resulting from partial digestion with Sau3A (pBHK10). The complete nucleotide sequence of the trxA gene and its promoter was determined. Comparison of the DNA sequence with the published amino acid sequence revealed the inversion of two amino acid pairs and the possibility of a leader peptide 18 amino acids in length. Three-factor P1 transductional crosses and physical mapping experiments have determined a map order of ilv-trxA-uvrD-corA-metE. 相似文献
104.
105.
《Biomarkers》2013,18(6):530-535
Context: In management of community-acquired pneumonia (CAP), excellent biomarkers for inflammation would be helpful in our practice.Objectives: Kinetics of c-reactive protein (CRP) and serum amyloid A (SAA) was characterized, using their biologic half-life times.Materials and methods: Time course of CRP and SAA levels in the successfully treated 36 CAP patients were investigated and their half-life times were determined and compared.Results & Discussions: SAA and CRP declined in an exponential mean and the biologic half-life times of SAA levels was 34.9?±?28.7?h, significantly shorter than that of CRP, 46.4?±?21.7?h (p?=?0.0014). Conclusion: The kinetic evidence, presented as biologic half-life times of CRP and SAA, helps us make a clinical assessment of CAP patients. 相似文献
106.
107.
Songwen Zhang Qiangyuan Liu Juan Wang Douglas C. Harnish 《Biochemical and biophysical research communications》2009,379(2):476-479
C-reactive protein (CRP), a human acute-phase protein, is a risk factor for future cardiovascular events and exerts direct pro-inflammatory and pro-atherogenic properties. The farnesoid X receptor (FXR), a member of the nuclear hormone receptor superfamily, plays an essential role in the regulation of enterohepatic circulation and lipid homeostasis. In this study, we report that two synthetic FXR agonists, WAY-362450 and GW4064, suppressed interleukin-6-induced CRP expression in human Hep3B hepatoma cells. Knockdown of FXR by short interfering RNA attenuated the inhibitory effect of the FXR agonists and also increased the ability of interleukin-6 to induce CRP production. Furthermore, treatment of wild type C57BL/6 mice with the FXR agonist, WAY-362450, attenuated lipopolysaccharide-induced serum amyloid P component and serum amyloid A3 mRNA levels in the liver, whereas no effect was observed in FXR knockout mice. These data provide new evidence for direct anti-inflammatory properties of FXR. 相似文献
108.
Tony Christopeit 《Analytical biochemistry》2009,391(1):39-22
The interactions between Ca2+ and C-reactive protein (CRP) have been characterized using a surface plasmon resonance (SPR) biosensor. The protein was immobilized on a sensor chip, and increasing concentrations of Ca2+ or phosphocholine were injected. Binding of Ca2+ induced a 10-fold higher signal than expected from the molecular weight of Ca2+. It was interpreted to result from the conformational change that occurs on binding of Ca2+. Two sites with different characteristics were distinguished: a high-affinity site with KD = 0.03 mM and a low-affinity site with KD = 5.45 mM. The pH dependencies of the two Ca2+ interactions were different and enabled the assignment of the different sites in the three-dimensional structure of CRP. There was no evidence for cooperativity in the phosphocholine interaction, which had KD = 5 μM at 10 mM Ca2+. SPR biosensors can clearly detect and quantify the binding of very small molecules or ions to immobilized proteins despite the theoretically very low signals expected on binding, provided that significant conformational changes are involved. Both the interactions and the conformational changes can be characterized. The data have important implications for the understanding of the function of CRP and suggest that Ca2+ is an efficient regulator under physiological conditions. 相似文献
109.
C-reactive protein (CRP) is elevated in cardiovascular disease and binds to oxidized phosphatidylcholine (oxPtC) in the low-density lipoprotein (LDL) surface. In the present study, we tested if CRP influences the susceptibility of LDL to oxidation. At physiological concentrations of 1-7mug/ml, CRP strongly inhibited copper-mediated oxidation of LDL and phospholipid liposomes in a concentration-dependent manner. Similar concentrations of different monoclonal antibodies or albumin did not influence LDL oxidation. Antioxidant activity of CRP was inhibited by phosphocholine (PC), indicating that the observed activity involves binding of CRP to oxPtC. These results suggest that CRP may limit atherogenic oxidation of LDL in vivo. 相似文献
110.