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991.

Food proteins from different sources can provide beneficial effects on human health by releasing the bioactive peptides that are integral part of their native structure. In this study, we tested the biological potential of hempseed protein hydrolysates (HPHs) obtained from hempseed cake protein isolate. The HPHs were prepared by enzyme hydrolysis using three different proteases of microbial origin: Alcalase®, Neutrase® and Protamex®. The antioxidant activity of the obtained hydrolysates was determined by oxygen radical absorbance capacity (ORAC) assay, while the proliferative effects on normal (HaCaT) and cancer (HeLa) cells were determined by the CellTiter 96® AQueous One Solution Reagent (MTS) assay. HPHs showed dose-dependent antiproliferative effects on HeLa cells and stimulatory effects on the proliferation of HaCaT cells. HPH obtained by Neutrase® (HPH-N) showed the highest antioxidant activity expressed as an ORAC value. The protective effect of HPH-N on H2O2-induced oxidative stress in normal and cancer cells was evaluated and 1 mg/mL of HPH-N significantly reduced the formation of intracellular reactive oxygen species (ROS) in both cell lines. The obtained results indicate the benefits of HPHs as potential natural antioxidants for the food industry and contribute to the growing trend of utilizing hempseed by-products.

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992.
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994.
The reaction of OCO chelated organolithium compound LLi (1) (L = 2,6-(t-BuOCH2)2C6H3) with SbCl3 in 2:1 molar ratio gave diorganoantimony compound L2SbCl (2). The reactions of the compound 2 with selected lithium acetylides resulted to the Sb←O coordinated antimony acetylides L2Sb(CCR) (R = Ph, (3), t-Bu (4), Me3Si (5)). All studied compounds were characterized by the help of elemental analysis, 1H and 13C NMR spectroscopy and IR spectroscopy. Molecular structures of the compounds 2-4 were determined using the X-ray diffraction technique in the solid state.  相似文献   
995.
In this paper synthesis of macrolones 118 starting from azithromycin is reported. Two key steps in the construction of the linker between macrolide and quinolone moiety, are formation of central ether bond by alkylation of unactivated OH group, and formation of terminal C–C bond at 6-position of the quinolone unit. Due to the difficulty in formation of these two bonds the study of alternative synthetic methodologies and optimization of the conditions for the selected routes was required. Formation of C-4″-O-ether bond was completed by modified Michael addition, whereas O-alkylation via diazonium cation proved to be the most effective in formation of the central allylic or propargylic ether bond. Comparison of Heck and Sonogashira reaction revealed the former as preferred route to the C–C bond formation at C(6) position of the quinolone unit. Most of the target compounds exhibited highly favorable antibacterial activity against common respiratory pathogens, without significant cytotoxicity profile when tested in vitro on eukaryotic cell lines.  相似文献   
996.
There are several methods for presbyopia treatment. Refractive lens exchange (RLE) followed by multifocal intraocular lens (MFIOL) implantation enables high rate of spectacle independence but have some visual disturbances. Laser in Situ Keratomileusis (LASIK) monovision gives patient ability to have good distant vision with dominant eye and good near vision with nondominant eye. In this prospective randomized study we wanted to compare clinical outcomes in patients who underwent either of the mentioned procedures. The first group included 50 patients (N = 100 eyes) who underwent RLE with MFIOL implantation and the second group included 50 patients (N = 100 eyes) who underwent LASIK monovision as presbyopia treatment. Uncorrected distant, near and intermediate visual acuity, patient's subjective satisfaction and visual disturbances were measured. Follow up was 6 months. Patients in RLE group had better near uncorrected visual acuity (UCVA) and patients in LASIK monovision group had better distant and intermediate vision. Patients in RLE group reported visual disturbances (halo, glare). Patients satisfaction and spectacle independence was high in both groups. Refractive lens exchange with multifocal intraocular lens implantation and LASIK monovision are effective methods for presbyopia treatment. LASIK monovision with -0.50D - 1.25D of residual dioptry at nondominant eye in patients under 50 years enables good vision at all distances without affecting stereovision. Patient selection and preoperative counseling are key to success.  相似文献   
997.
Mouth dryness (MD) is usually followed by inadequate mechanical cleaning of the mouth and decrease in the levels of salivary antimicrobial proteins (including secretory immunoglobulin A (sIgA)). It is accompanied by difficulties during speaking and food swallowing, with an unpleasant taste, burning sensations in the mouth and higher susceptibility to oral diseases. Low-level laser treatment (LLLT) can intensify cell metabolism and its application on salivary glands could improve salivation. The purpose of this study was to evaluate the effects of LLLT on salivation of patients suffering from MD. The study included 17 patients with MD. Their major salivary glands were treated with low intensity laser BTL2000 on 10 occasions. The whole unstimulated and stimulated saliva quantities were measured just before the 1st, after the 10th and thirty days following the last (10th) treatment. In the samples of unstimulated saliva concentrations of sIgA were estimated by using ELISA method and its quantity in the time unit was calculated. The visual analogue scale (VAS) score was used to assess burning and/or pain intensity at these three time points. Statistical tests revealed significant salivation improvement quantitatively and qualitatively, i.e. increase in the quantity of saliva and sIgA. VAS score was also significantly improved and no side effects were observed. Conclusions: According to the results of this study, application of LLLT to xerostomic patients' major salivary glands stimulates them to produce more saliva with better antimicrobial characteristics and improves the difficulties that are associated with MD. This simple non-invasive method could be used in everyday clinical practice for the treatment of MD.  相似文献   
998.
Availability of irrigation water of appropriate quality is becoming critical in many regions. Excess salt in irrigation water represents a risk for crop yield, crop quality, and soil properties. During the short vegetation period, field peas require high amounts of water, and irrigation is often indispensable for successful production. Steady presence of NaCl (0.1, 0.2, 0.6 or 1.2 g NaCl L−1 in 1/2 strength Hoagland nutrient solution) under semi-controlled conditions reduced growth and resulted in shorter vegetation. Disturbances in the peas’ water regime were provoked by NaCl, as water content in pea tissues was reduced and stomatal density and stomatal diffusive resistance increased in the presence of higher NaCl concentrations. Concentration of Na+ increased in all pea tissues with increased NaCl concentration in the nutrient medium. In the presence of NaCl, concentrations of K+, Ca2+ and Pi increased in roots, stems and leaves, and decreased and in pods and grains. Concentration ratios Na+/K+, Na+/Ca2+, K+/Ca2+ and (Na++K+)/Ca2+ in various plant parts were affected as well, but magnitudes of changes were variable. Continuous presence of NaCl in concentrations frequently met in irrigation waters significantly reduced pea growth, impaired the water regime, and altered plant chemical composition.  相似文献   
999.
Estrela S  Gudelj I 《PloS one》2010,5(11):e14121
The act of cross-feeding whereby unrelated species exchange nutrients is a common feature of microbial interactions and could be considered a form of reciprocal altruism or reciprocal cooperation. Past theoretical work suggests that the evolution of cooperative cross-feeding in nature may be more challenging than for other types of cooperation. Here we re-evaluate a mathematical model used previously to study persistence of cross-feeding and conclude that the maintenance of cross-feeding interactions could be favoured for a larger parameter ranges than formerly observed. Strikingly, we also find that large populations of cross-feeders are not necessarily vulnerable to extinction from an initially small number of cheats who receive the benefit of cross-feeding but do not reciprocate in this cooperative interaction. This could explain the widespread cooperative cross-feeding observed in natural populations.  相似文献   
1000.
The cell cycle inhibitor p21CDKN1A has been shown to participate in nucleotide excision repair by interacting with PCNA. Here we have investigated whether p21 plays a role in base excision repair (BER), by analyzing p21 interactions with BER factors, and by assessing the response of p21?/? human fibroblasts to DNA damage induced by alkylating agents. Absence of p21 protein resulted in a higher sensitivity to alkylation-induced DNA damage, as indicated by reduced clonogenic efficiency, defective DNA repair (assessed by the comet test), and by persistence of histone H2AX phosphorylation. To elucidate the mechanisms at the basis of the function of p21 in BER, we focused on its interaction with poly(ADP-ribose) polymerase-1 (PARP-1), an important player in this repair process. p21 was found to bind the automodification/DNA binding domain of PARP-1, although some interaction occurred also with the catalytic domain after DNA damage. This association was necessary to regulate PARP-1 activity since poly(ADP-ribosylation) induced by DNA damage was higher in p21?/? human fibroblasts than in parental p21+/+ cells, and in primary fibroblasts after p21 knock-down by RNA interference. Concomitantly, recruitment of PARP-1 and PCNA to damaged DNA was greater in p21?/? than in p21+/+ fibroblasts. This accumulation resulted in persistent interaction of PARP-1 with BER factors, such as XRCC1 and DNA polymerase β, suggesting that prolonged association reduced the DNA repair efficiency. These results indicate that p21 regulates the interaction between PARP-1 and BER factors, to promote efficient DNA repair.  相似文献   
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