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71.
Proteomics methodologies hold great promise in basic renal research and clinical nephrology. The classical approach for proteomic analysis couples two-dimensional gel electrophoresis (2-DE) with protein identification by mass spectrometry, to produce more global information regarding normal protein expression and alterations in different physiological and pathological states. In this report we have expanded the identification of proteins in the renal cortex, improving the previously published map to facilitate the study of different diseases affecting the human kidney. About 250 spots were analyzed by peptide mass fingerprinting, 89 proteins and 74 isoforms for some of them were identified and implemented in the normal human renal cortex 2-DE reference map. This more comprehensive view of the proteome of the human renal cortex could be of invaluable help to the differential proteomic display of urological diseases.  相似文献   
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The hypothesis that phosphorylation of the minor photosystem II antenna complex CP29 (CP34 formation) in Zea mays (cv. Dekalb DK300), under conditions of illumination and low temperature stress, may constitute a protective mechanism against photoinhibition, has been investigated. It is demonstrated that illumination at low temperature induces a marked increase in reversible non‐photochemical quenching yield of chlorophyll fluorescence, together with CP34 formation. These two parameters, however, are not related as CP34 dephosphorylates to CP29 in the dark, with a half‐time of about 10 min, while the enhanced non‐photochemical quenching yield is stable for many hours. The enhanced non‐photochemical quenching yield seems to correlate with zeaxanthin formation. The influence of CP34 formation on photoinhibition was also directly investigated. No measurable effect on this parameter could be observed after treatment with high light. It is concluded that CP34 is probably not directly involved in photoprotective processes.  相似文献   
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In this study, a large-scale field survey was conducted to describe the biogeography of sulfate-reducing prokaryotes (SRPs) in river floodplains. Fingerprints obtained with three methods, i.e. 16S rRNA gene-based oligonucleotide microarray, dsrB-based denaturing gradient gel electrophoresis (DGGE) and polar lipid-derived fatty acid (PLFA) analyses, were used as a proxy to describe the SRPs community diversity. Each set of profiles was subjected to a combined multivariate/correlation analysis in order to compare SRP community profiles and to highlight the environmental variables influencing the SRPs distribution along environmental gradients. Floodplain soils harbored distinct SRP communities displaying biogeographic patterns. Nearly all profiles from the tidal sites consistently separated from the nontidal sites, independently from the screening method and the multivariate statistics used. The distribution of the microarray/DGGE/PLFA-based fingerprints in the principal component plots could be correlated to eight soil variables, i.e. soil organic matter, total nitrogen, total phosphorous and total potassium, and extractable ammonium, nitrate, phosphate and sulfate, as well as seven pore water variables, i.e. phosphate, sulfate, sulfide, chloride, sodium, potassium and magnesium ions. Indication of a salinity- and plant nutrient-dependent distribution of SRPs related to Desulfosarcina, Desulfomonile and Desulfobacter was suggested by microarray, DGGE and PLFA analyses.  相似文献   
76.
Dopamine (DA) receptor and NMDA receptor (NMDAR) activation in the lateral (LA) nucleus of the amygdala plays a critical role in emotional processing. Several distinct mechanisms regulate the molecular cross-talk between DA receptors and NMDARs in different brain regions; however, the cellular mechanism through which DA modulates NMDARs in LA projection neurons has not been studied. Here, we investigated the effect of DA receptor activation on NMDAR currents in LA projection neurons recorded in amygdala slices obtained from young rats. We found that DA reduces NMDAR current amplitudes in an additive manner through the activation of both D1-like and D2-like receptors. The reduction of NMDAR current amplitudes by D1-like receptor activation is mediated by a protein-protein interaction between the D1R and the NMDAR, while the regulation of NMDAR activity by D2-like receptors is elicited through a G protein-dependent pathway controlled by D4R. The results of our investigation show for the first time a functional interplay between D1R and D4R that mediates coincident G protein-independent and dependent regulation of NMDARs.  相似文献   
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The aim of this study is to provide new syntaxa for the Italian vegetation checklist. For the class Rhamno–Prunetea which includes the class Paliuretea the new alliance Rhamno saxatilis–Paliurion spinae-christi is described, that is included in the order Paliuretalia spinae-christi with a central-western Mediterranean and sub-Mediterranean distribution. Otherwise, the more thermophilous Paliurus spina-christi vegetation is included in the new suballiance named as Oleo sylvestris–Paliurenion spinae-christi within the alliance Oleo–Ceratonion of the class Quercetea ilicis. For the class Trifolio–Geranietea medii, a new alliance named Hyperico calabricae–Asphodelion macrocarpi is proposed here.  相似文献   
79.
Plastocyanin is a soluble copper-containing protein present in the thylakoid lumen, which transfers electrons to photosystem I. In the chloroplast of the flowering plant Arabidopsis thaliana, a cytochrome c6-like protein is present, which was recently suggested to function as an alternative electron carrier to plastocyanin. We show that Arabidopsis plants mutated in both of the two plastocyanin-coding genes and with a functional cytochrome c6 cannot grow photoautotrophically because of a complete block in light-driven electron transport. Even increased dosage of the gene encoding the cytochrome c6-like protein cannot complement the double mutant phenotype. This demonstrates that in Arabidopsis only plastocyanin can donate electrons to photosystem I in vivo.  相似文献   
80.

Background

Although the mouse is the animal model most widely used to study the pathogenesis and treatment of human diseases, reference values for biochemical parameters are scanty or lacking for the most frequently used strains. We therefore evaluated these parameters in the C57BL/6J, 129SV/EV and C3H/HeJ mice.

Methodology/Principal Findings

We measured by dry chemistry 26 analytes relative to electrolyte balance, lipoprotein metabolism, and muscle/heart, liver, kidney and pancreas functions, and by automated blood counter 5 hematological parameters in 30 animals (15 male and 15 female) of each mouse strain at three age ranges: 1–2 months, 3–8 months and 9–12 months. Whole blood was collected from the retro-orbital sinus. We used quality control procedures to investigate analytical imprecision and inaccuracy. Reference values were calculated by non parametric methods (median and 2.5th and 97.5th percentiles). The Mann-Whitney and Kruskal-Wallis tests were used for between-group comparisons. Median levels of GLU, LDH, Chol and BUN were higher, and LPS, AST, ALP and CHE were lower in males than in females (p range: 0.05–0.001). Inter-strain differences were observed for: (1) GLU, t-Bil, K+, Ca++, PO4 (p<0.05) and for TAG, Chol, AST, Fe++ (p<0.001) in 4–8 month-old animals; (2) for CK, Crea, Mg++, Na++, K+, Cl (p<0.05) and BUN (p<0.001) in 2- and in 10–12 month-old mice; and (3) for WBC, RBC, HGB, HCT and PLT (p<0.05) during the 1 year life span.

Conclusion/Significance

Our results indicate that metabolic variations in C57BL/6J, 129SV/EV and C3H/HeJ mice after therapeutic intervention should be evaluated against gender- and age-dependent reference intervals.  相似文献   
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