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991.
Bangwei Luo Zhishang Wang Zhiyuan Zhang Zigang Shen Zhiren Zhang 《生物化学与生物物理学报:疾病的分子基础》2019,1865(2):339-349
Obesity has been linked with altered acute inflammation resolution which contributes to obesity-related clinical complications; however, the mechanisms that contribute to obesity-related unresolved inflammation are not fully known. Here we demonstrated that the deficiency of macrophage erythropoietin (EPO) signaling contributed to delayed acute inflammation resolution in diet-induced obese mice. In zymosan-induced acute peritonitis, in line with the delayed resolution of inflammation, the induction of macrophage EPO signaling was significantly reduced in obese mice relative to normal mice. Exogenous EPO induced macrophage EPO signaling and promoted acute inflammation resolution in obese mice. Efferocytosis of apoptotic cells by macrophages which is central in inflammation resolution was impaired in obese mice and restored by exogenous EPO. Mechanistically, macrophage peroxisome proliferator-activated receptor-γ (PPARγ) was greatly reduced in obese mice and EPO increased macrophage PPARγ to promote efferocytosis in obese mice. Together, our results identify an important mechanism underlying aberrant acute inflammation resolution in obesity, with important implications for regulating unresolved acute inflammation and normalizing macrophage defects in obese and diabetic individuals. 相似文献
992.
Tetsuo Takemura Go Emoto Jun Satoh Yoshitaka Kobayashi Chihiro Yaginuma Yuta Takahashi Takamitsu Utsukihara C. Akira Horiuchi 《Journal of Molecular Catalysis .B, Enzymatic》2008,55(3-4):104-109
Both enantiomers of 2,2′-dihydroxy-4,4′,5,5′,6,6′-hexamethybiphenyl (2), a potentially useful chiral synthon, were obtained with >99% ee in high enantioselectivity by cholesterol esterase or porcine pancreas lipase (PPL)-mediated hydrolysis of the corresponding (±)-dipentanoate or (±)-dihexanoate, respectively. Absolute configuration of (S)-3-bromo-2,6′-dimethoxy-4,5,6,2′,3′,4′-hexamethyl-biphenyl (2h) was determined by X-ray analysis. 相似文献
993.
Single particle tracking (SPT) techniques were developed to explore bio‐molecules dynamics in live cells at single molecule sensitivity and nanometer spatial resolution. Recent developments in quantum dots (Qdots) surface coating and bio‐conjugation schemes have made them most suitable probes for live cell applications. Here we review recent advancements in using quantum dots as SPT probes for live cell experiments. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
Scheltema RA Kamleh A Wildridge D Ebikeme C Watson DG Barrett MP Jansen RC Breitling R 《Proteomics》2008,8(22):4647-4656
With the advent of a new generation of high-resolution mass spectrometers, the fields of proteomics and metabolomics have gained powerful new tools. In this paper, we demonstrate a novel computational method that improves the mass accuracy of the LTQ-Orbitrap mass spectrometer from an initial +/- 1-2 ppm, obtained by the standard software, to an absolute median of 0.21 ppm (SD 0.21 ppm). With the increased mass accuracy it becomes much easier to match mass chromatograms in replicates and different sample types, even if compounds are detected at very low intensities. The proposed method exploits the ubiquitous presence of background ions in LC-MS profiles for accurate alignment and internal mass calibration, making it applicable for all types of MS equipment. The accuracy of this approach will facilitate many downstream systems biology applications, including mass-based molecule identification, ab initio metabolic network reconstruction, and untargeted metabolomics in general. 相似文献
995.
996.
酶法拆分手性化合物HPBE 总被引:5,自引:0,他引:5
R-HPBE(2-羟基4苯基丁酸乙酯)是一种重要的医药中间体,可以通过脂肪酶催化水解外消旋体得到。介绍了此催化过程的机理、工艺、产物检测等,并通过酶在疏水载体上的界面吸附对酶进行固定化,以提高酶活及对映选择性。 相似文献
997.
The distributions of ATP and reducing equivalents were estimated with the aid of a pre-constructed bionetwork describing the growth characteristics of Corynebacterium glutamicum cultivated in a pH-auxostat. Results showed that the specific growth rate (μ) imposed different degrees of influences on both ATP and reducing equivalents. The ATP generated from the TCA cycle increased about 33% as μ was raised from 0.23 to 0.45 h−1, while the ATP obtained from the EMP pathway decreased from 32.90 to 2.12% over the same growth span. In contrast, the reducing equivalents contributed from both the TCA cycle and the EMP pathway varied slightly. The ATP obtained through glucose utilization was insufficient to balance the microbial demands. As a result, the transformation among amino acids to compensate the ATP requirement was noticed. To enhance product resolution from an amino acid mix, metabolic nodes at AKG, PYR, PEP, and RU5P have been identified and could be considered concurrently as the potential nodes for manipulating metabolic flows in C. glutamicum. 相似文献
998.
999.
Predicting the three-dimensional structure of proteins is still one of the most challenging problems in molecular biology. Despite its difficulty, several investigators have started to produce consistently low-resolution predictions for small proteins. However, in most of these cases, the prediction accuracy is still too low to make them useful. In the present article, we address the problem of obtaining better-quality predictions, starting from low-resolution models. To this end, we have devised a new procedure that uses these models, together with structure comparison methods, to identify the structural family of the target protein. This would allow, in a second step not described in the present work, to refine the predictions using conserved features of the identified family. In our approach, the structure database is investigated using predictions, at different accuracy levels, for a given protein. As query structures, we used both low-resolution versions of the native structures, as well as different sets of low accuracy predictions. In general, we found that for predictions with a resolution of > or =5-7 A, structure comparison methods were able to identify the fold of a protein in the top positions. 相似文献
1000.
An assessment of potential contamination risk associated with devices routinely used in hospitals and clinical laboratories for sampling and storage of whole blood and serum was made by analysis of leachates from the devices. The devices checked were disposable stainless steel needles, different types of blood collection tubes; serum separation tubes, disposable plastic pipettes and plastic vials used for serum storage. Concentrations of about 70 elements in solution after leaching with 0.05 mol l(-1) HNO3 were determined by double focusing sector field inductively coupled plasma mass spectrometry (sector field ICP-MS). For the elements present in blood/serum at concentrations higher than 10 ng ml(-1) (Na, Ca, Mg, P, Fe, Br, Si, Zn, Cu, Rb, Se and I) contribution from devices was as a rule negligible (less than 1% of expected concentrations in the body fluids), but for the majority of trace and ultra-trace elements it may significantly affect or even prevent accurate determination. The highest trace element contribution was found to derive from commercially available blood collection and serum separation tubes. Apparent concentrations of Al, Ba, Th, rare earth, and some other elements resulting from contamination were higher than normal serum concentrations all types of tubes tested for. 相似文献