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41.
Sara M Mohamed Emam A Abdel-Rahim Tahany AA Aly AbdelMoneim M Naguib Marwa S Khattab 《Experimental biology and medicine (Maywood, N.J.)》2022,247(5):385
Increased environmental pollution and unhealthy lifestyle are blamed for escalated chronic diseases. Exposure to aflatoxins was recently suggested to have a role in the increased incidence of type 2 diabetes mellitus. Diet modification and consumption of different functional food are now gaining attention, especially in diabetes management. This study investigates the effect of a diet containing barley microgreen against diabetes induced by streptozotocin with or without aflatoxin administration in rats. Barley microgreen was rich in 3′-Benzyloxy-5,6,7,4′-tetramethoxyflavone (48.8% of total) followed by 5β,7βH,10α-Eudesm-11-en-1α-ol (18.46%). Streptozotocin injection and/or aflatoxin administration significantly elevated glucose level, decreased insulin level, decreased β-cell function, deteriorated liver and kidney function parameters, and induced oxidative stress in the liver. Histopathology revealed irregular small-sized islets and decreased area % of insulin-positive beta cells in the pancreas, hepatic degeneration, nephropathy, and neuropathy in diabetic and/or aflatoxin administered rats compared to control. Barley microgreen diet fed to diabetic rats with or without aflatoxin alleviated all evaluated parameters. Barley microgreen diet also ameliorated the toxic effect of aflatoxin. In conclusion, exposure to aflatoxin aggravated diabetes and its complication. The incorporation of barley microgreen in the diet was able to control type 2 diabetes mellitus and the improved outcomes observed with barley microgreen treatments involved or occurred in conjunction with improved biomarkers of oxidative stress. 相似文献
42.
Tymen H Rateau G Guillet K Gall B Ramounet-Le Gérasimo P Fritsch P 《Canadian journal of physiology and pharmacology》2002,80(7):733-741
Although skin contamination by radionuclides is the most common cause of nuclear workers accidents, few studies dealing with the penetration of radioactive contamination through the skin are available. This work is a review of experimental methods that allow to assess transfer of radionuclides through the skin in occupational conditions, with or without skin trauma. The first section describes the different methods applied for skin transfer assessment of chemicals used in pharmacology. Major radionuclide contamination accidents can be associated with skin traumas. Thus, the second section describes the adaptation of these methods to radiotoxicology. Finally, the third section is an in vivo investigation of cobalt transfer (57CoCl2) through undamaged and damaged skin which simulates different industrial accident conditions (excoriation, acid or alcalin burn, scalding, branding). 相似文献
43.
Effect of high pressure on the photochemical reaction center from Rhodobacter sphaeroides R26.1 下载免费PDF全文
High-pressure studies on the photochemical reaction center from the photosynthetic bacterium Rhodobacter sphaeroides, strain R26.1, shows that, up to 0.6 GPa, this carotenoid-less membrane protein does not loose its three-dimensional structure at room temperature. However, as evidenced by Fourier-transform preresonance Raman and electronic absorption spectra, between the atmospheric pressure and 0.2 GPa, the structure of the bacterial reaction center experiences a number of local reorganizations in the binding site of the primary electron donor. Above that value, the apparent compressibility of this membrane protein is inhomogeneous, being most noticeable in proximity to the bacteriopheophytin molecules. In this elevated pressure range, no more structural reorganization of the primary electron donor binding site can be observed. However, its electronic structure becomes dramatically perturbed, and the oscillator strength of its Q(y) electronic transition drops by nearly one order of magnitude. This effect is likely due to very small, pressure-induced changes in its dimeric structure. 相似文献
44.
In this work we have selectively released the 800 nm absorbing bacteriochlorophyll a molecules of the LH2 protein from the photosynthetic bacterium Rhodopseudomonas acidophila, strain 10050, and replaced them with chlorophyll a (Chla). A combination of low-temperature electronic absorption, resonance Raman and site-selection fluorescence spectroscopies revealed that the Chla pigments are indeed bound in the B800 binding site; this is the first work that formally proves that such non-native chlorins can be inserted correctly into LH2. 相似文献
45.
Richard B. Forward Jr Elizabeth Freeman Kristen Gall Katie Saba 《Marine and Freshwater Behaviour and Physiology》2013,45(5):305-319
The supratidal amphipod Talorchestia longicornis Say has a circadian rhythm in activity, in which it is active on the substrate surface at night and inactive in burrows during the day. The present study determined: (1) the circadian rhythms in individual versus groups of amphipods; (2) the range of temperature cycles that entrain the circadian rhythm; (3) entrainment by high-temperature cycles versus light?:?dark cycles, and (4) seasonal substrate temperature cycles. The circadian rhythm was determined by monitoring temporal changes in surface activity using a video system. Individual and groups of amphipods have similar circadian rhythms. Entrainment occurred only to temperature cycles that included temperatures below 20°C (10–20, 15–20, 17–19, 15–25°C) but not to temperatures above 20°C (20–25, 20–30°C), and required only a 2°C temperature cycle (17–19°C). Diel substrate temperatures were above 20°C in the summer and below 20°C during the winter. Upon simultaneous exposure to a diel high-temperature cycle (20–30°C) and a light?:?dark cycle phased differently, amphipods entrained to the light?:?dark cycle. Past studies found that a temperature cycle below 20°C overrode the light?:?dark cycle for entrainment. The functional significance of this change in entrainment cues may be that while buried during the winter, the activity rhythm remains in phase with the day?:?night cycle by the substrate temperature cycles. During the summer, T. longicornis switches to the light?:?dark cycle for entrainment, perhaps as a mechanism to phase activity precisely to the short summer nights. 相似文献
46.
47.
AA Smith 《Biotechnic & histochemistry》2016,91(6):396-400
One can determine the best dilution of a primary antibody for immunohistochemistry that uses horseradish peroxidase conjugated to a secondary antibody by testing increasing concentrations sequentially on the same tissue section. When the same tissue section is incubated repeatedly with increasing concentrations of primary antibodies to epithelial membrane antigen, smooth muscle α-actin, or vimentin using alkaline phosphatase conjugated to a secondary antibody as the reporter, the best staining was obtained with a less concentrated primary antibody than was optimal for a single staining test. The best concentration of primary antibody for single run staining using an alkaline phosphatase reporting system is usually four times the best concentration for staining with multiple runs. The optimal concentration can be determined by denaturing the residual alkaline phosphatase and extracting residual stain by incubating the section in 4:1 diglyme:phosphate buffered saline for 20 min at 80o C between tests of primary antibody concentrations. I tested the method for four chromogens from one supplier and one chromogen from a different supplier. 相似文献
48.
Andrew Gall Justin P. Ridge Bruno Robert Richard J. Cogdell Michael R. Jones Paul K. Fyfe 《Photosynthesis research》1999,59(2-3):223-230
The effect of mutagenesis on the detailed conformation of the carotenoid cofactor of the bacterial reaction centre has been examined using resonance Raman spectroscopy. Four single site mutations were made, removing polar residues that line the binding pocket for spheroidenone in the reaction centre from Rhodobacter sphaeroides. All of the mutations caused changes in the relative intensity of bands in the 2 frequency region of the carotenoid resonance Raman spectrum, suggesting a change in the geometry of the central 15,15-cis bond of the spheroidenone. In addition, increased splitting of the 1 vibrational modes in two of the mutant RCs indicated a reduction of the effective conjugation length of the spheroidenone, possibly due to an increased distortion from a planar geometry along the C=C backbone of the spheroidenone. These changes in the detailed conformation of the reaction centre carotenoid do not affect the optical properties o f the cofactor, and are beyond the limits of detection of X-ray crystallography as currently applied to the bacterial reaction centre. 相似文献
49.
土壤中棉花黄萎病菌SYBR Green Ⅰ荧光RT-PCR定量检测技术研究 总被引:3,自引:0,他引:3
为实现田间土壤棉花黄萎病菌的早期检测,建立了土壤中棉花黄萎病菌的SYBR Green I荧光定量PCR检测方法。以含342bp PCR扩增产物的阳性质粒为参考,构建了标准曲线,并对该曲线的特异性、敏感性、可重复性进行了评价。结果表明,该方法具有快速、特异性强、敏感度高等特点。检测范围在3.8×103-3.8×108copies/μL之间有良好的线性关系,相关系数R2为0.996,扩增效率为101.5%,灵敏度比常规PCR方法高102倍。 相似文献
50.