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The effects of feeding two levels of rice bran oil (RBO) on the growth, lipid parameters, and fatty acid composition of the plasma and liver of rats (Wistar strain) were compared with those produced on animals which had been fed the same levels of peanut oil (PNO). The control animals were fed synthetic diets containing 5 and 20% peanut oil (PNO) and the experimental groups were fed similar diets, containing the same level of rice bran oil (RBO). There was no significant difference with respect to the organ weights between the control and the experimental groups. In general, groups fed 20% oil gained more weight than groups fed 5% oil. The animals which received rice bran oil in their diet had, in general, comparatively lower levels of cholesterol, triglycerides and phospholipids. On the other hand, animals receiving 20% rice bran oil in their diet, showed an increase of 20% in high density lipoproteins (HDL-C), within 18 weeks (p<0.05), when compared to the animals fed with peanut oil. Similarly, low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) were lower in RBO-fed groups, than in the PNO-fed groups. There was, however, no significant differences in the cholesterol/phospholipid (C/P) ratio of the two groups. Analysis of plasma and of liver fatty acids indicated, in a general way, the type of fat consumed. There were no significant difference in the P/S ratio, nor any in the oleic/linoleic, oleic/stearic, palmitoleic/palmitic, oleic/palmitic, and oleic/palmitoleic ratios. Furthermore, levels of saturated (SAFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids were identical in both the groups. Thus, our results suggest that feeding a high level of rice bran oil (RBO) has no deleterious effect on the growth and blood lipid profile of rats.Abbreviations PNO peanut oil - RBO rice bran oil - HDL-C high density lipoprotein cholesterol - LDL-C low density lipoprotein cholesterol - VLDL-C very low density lipoprotein cholesterol - SAFA saturated fatty acids - MUFA mono-unsaturated fatty acids  相似文献   
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A lysogenic Streptomyces sp., strain NS.A4, which was isolated from the nodule surface of black gram (Vigna mungo (L.) Hepper), was found to inhibit rhizobia of fast-and slow-growing strains of cowpeas and soybeans. It exhibited plaques when there was a change in cultural conditions. Repeated culturing of the organism in nutrient agar and broth confirmed the infection of Streptomyces sp. strain NS.A4 by an actinophage. Addition of the culture filtrate of Streptomyces sp. strain NS.A4 to shaken broth cultures of three other Streptomyces spp. resulted in phage infection.  相似文献   
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Plasmonics - This study shows development of highly sensitive and stable localized surface plasmon resonance (LSPR)-active U-bent glass and polymeric optical fiber (GOF and POF) sensor probes by a...  相似文献   
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The discovery of broadly neutralizing antibodies that can neutralize multiple strains or subtypes of a pathogen has renewed interest in the development of broadly protective vaccines. To that end, there has been an interest in designing immunofocusing strategies to direct the immune response to specific, conserved regions on antigenic proteins. Modulation of glycosylation is one such immunofocusing strategy; extensive glycosylation is often exploited by pathogens for immune evasion. Masking epitopes on protein immunogens with “self” glycans can also shield the underlying protein surface from humoral immune surveillance. We review recent advances in applying glycosylation as an immunofocusing tool. We also highlight recent interesting work in the HIV-1 field involving the identification and elicitation of broadly neutralizing antibodies that incorporate glycans into their binding epitopes.  相似文献   
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While there has been considerable progress in designing protein–protein interactions, the design of proteins that bind polar surfaces is an unmet challenge. We describe the computational design of a protein that binds the acidic active site of hen egg lysozyme and inhibits the enzyme. The design process starts with two polar amino acids that fit deep into the enzyme active site, identifies a protein scaffold that supports these residues and is complementary in shape to the lysozyme active-site region, and finally optimizes the surrounding contact surface for high-affinity binding. Following affinity maturation, a protein designed using this method bound lysozyme with low nanomolar affinity, and a combination of NMR studies, crystallography, and knockout mutagenesis confirmed the designed binding surface and orientation. Saturation mutagenesis with selection and deep sequencing demonstrated that specific designed interactions extending well beyond the centrally grafted polar residues are critical for high-affinity binding.  相似文献   
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Parkinson disease (PD) is a chronic neurodegenerative disease characterized by a slow and progressive degeneration of dopaminergic neurons in substantia nigra. The pathophysiological mechanisms underlying PD remain unclear. Pin1, a major peptidyl-prolyl isomerase, has recently been associated with certain diseases. Notably, Ryo et al. (Ryo, A., Togo, T., Nakai, T., Hirai, A., Nishi, M., Yamaguchi, A., Suzuki, K., Hirayasu, Y., Kobayashi, H., Perrem, K., Liou, Y. C., and Aoki, I. (2006) J. Biol. Chem. 281, 4117–4125) implicated Pin1 in PD pathology. Therefore, we sought to systematically characterize the role of Pin1 in PD using cell culture and animal models. To our surprise we observed a dramatic up-regulation of Pin1 mRNA and protein levels in dopaminergic MN9D neuronal cells treated with the parkinsonian toxicant 1-methyl-4-phenylpyridinium (MPP+) as well as in the substantia nigra of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Notably, a marked expression of Pin1 was also observed in the substantia nigra of human PD brains along with a high co-localization of Pin1 within dopaminergic neurons. In functional studies, siRNA-mediated knockdown of Pin1 almost completely prevented MPP+-induced caspase-3 activation and DNA fragmentation, indicating that Pin1 plays a proapoptotic role. Interestingly, multiple pharmacological Pin1 inhibitors, including juglone, attenuated MPP+-induced Pin1 up-regulation, α-synuclein aggregation, caspase-3 activation, and cell death. Furthermore, juglone treatment in the MPTP mouse model of PD suppressed Pin1 levels and improved locomotor deficits, dopamine depletion, and nigral dopaminergic neuronal loss. Collectively, our findings demonstrate for the first time that Pin1 is up-regulated in PD and has a pathophysiological role in the nigrostriatal dopaminergic system and suggest that modulation of Pin1 levels may be a useful translational therapeutic strategy in PD.  相似文献   
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An effort has been made for the first time in Asia's largest brackish water lagoon, Chilika, to investigate the spatio-temporal variability in primary productivity (PP), bacterial productivity (BP), bacterial abundance (BA), bacterial respiration (BR) and bacterial growth efficiency (BGE) in relation to partial pressure of CO2 (pCO2) and CO2 air–water flux and the resultant trophic switchover. Annually, PP ranged between 24 and 376 µg C L?1 d?1 with significantly low values throughout the monsoon (MN), caused by light limitation due to inputs of riverine suspended matter. On the contrary, BP and BR ranged from 11.5 to 186.3 µg C L?1 d?1 and from 14.1 to 389.4 µg C L?1 d?1, respectively, with exceptionally higher values during MN. A wide spatial and temporal variation in the lagoon trophic status was apparent from BP/PP (0.05–6.4) and PP/BR (0.10–18.2) ratios. The seasonal shift in net pelagic production from autotrophy to heterotrophy due to terrestrial organic matter inputs via rivers, enhanced the bacterial metabolism during the MN, as evident from the high pCO2 (10,134 µatm) and CO2 air–water flux (714 mm m?2 d?1). Large variability in BGE and BP/PP ratios especially during MN led to high bacteria-mediated carbon fluxes which was evident from significantly high bacterial carbon demand (BCD >100% of PP) during this season. This suggested that the net amount of organic carbon (either dissolved or particulate form) synthesized by primary producers in the lagoon was not sufficient to satisfy the bacterial carbon requirements. Lagoon sustained low to moderate autotrophic–heterotrophic coupling with annual mean BCD of 231% relative to the primary production, which depicted that bacterioplankton are the mainstay of the lagoon biogeochemical cycles and principal players that bring changes in trophic status. Study disclosed that the high CO2 supersaturation and oxygen undersaturation during MN was attributed to the increased heterotrophic respiration (in excess of PP) fuelled by allochthonous organic matter. On a spatial scale, lagoon sectors such as south sector, central sector and outer channel recorded “net autotrophic,” while the northern sector showed “net heterotrophic” throughout the study period.  相似文献   
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