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71.
Urine is a clinical specimen often used in medical diagnostics for monitoring of elements concentrations and kidneys function. We determined the contents of magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe), lead (Pb), and cadmium (Cd) in 74 samples of 24-h urine (from 46 women and 28 men). The measurements were realized by the atomic absorption spectrometry (AAS) with atomization in the flame (FAAS) and in the graphite furnace (GFAAS). The received results were the subject of statistical analysis including the sex and age of volunteers. Moreover, correlations between the elements and the relationships between age and amounts of excreted elements with urine were tested. We found the statistically significant higher content of Zn in men’s urine than in womens one. Moreover, both adult women and men (>18 years) excreted much more Ca in urine in comparison to young subjects. Only in case of Pb the significant positive correlation between its amount in 24-h urine of all donors and age was stated. The correlation analysis has shown the significant positive relationships between Ca–Mg, Ca–Fe, Mg–Fe, Cu–Fe, Cu–Cd, Fe–Cd, and Pb–Cd in total samples of urine. Basing on our results, we concluded that the gender and age of donors may impact on the elemental status of 24-h urine.  相似文献   
72.
The purpose of the presented paper was to study the effect of high concentrations of tributyltin (TBT) on the potassium retention and fatty acid (FA) composition of the fungus Cunninghamella elegans recognized as a very efficient TBT degrader. An increase in TBT had a strong influence on the potassium concentration in the fungus. In growth medium without TBT, the potassium content of the fungal cells was 5.8 mg K+ g dry weight−1. The maximum concentration of K+ was 15.06 mg g−1 dry weight at 30 mg l−1 of TBT. The major FAs that characterized the tested strain were C16:0, C18:1, C18:2, C18:3 and C18:0. TBT in the concentration range 5–30 mg l−1 strongly influenced the FA composition. In the presence of the organotin, the degree of saturation increased. It suggests that the observed changes promote an increase in the lipid ordering of the membrane by reducing its permeability and inhibiting potassium ion efflux.  相似文献   
73.

Introduction

The purpose of this study was to analyze the data of patients with T-cell large granular lymphocyte (T-LGL) lymphocytosis associated with inflammatory arthropathy or with no arthritis symptoms.

Methods

Clinical, serological as well as histopathological, immuhistochemical, and flow cytometric evaluations of blood/bone marrow of 21 patients with T-LGL lymphocytosis were performed. The bone marrow samples were also investigated for T-cell receptor (TCR) and immunoglobulin (IG) gene rearrangements by polymerase chain reaction with heteroduplex analysis.

Results

Neutropenia was observed in 21 patients, splenomegaly in 10, autoimmune diseases such as rheumatoid arthritis (RA) in 9, unclassified arthritis resembling RA in 2, and autoimmune thyroiditis in 5 patients. T-LGL leukemia was recognized in 19 cases. Features of Felty syndrome were observed in all RA patients, representing a spectrum of T-LGL proliferations from reactive polyclonal through transitional between reactive and monoclonal to T-LGL leukemia. Bone marrow trephines from T-LGL leukemia patients showed interstitial clusters and intrasinusoidal linear infiltrations of CD3+/CD8+/CD57+/granzyme B+ lymphocytes, reactive lymphoid nodules, and decreased or normal granulocyte precursor count with left-shifted maturation. In three-color flow cytometry (FCM), T-LGL leukemia cells demonstrated CD2, CD3, and CD8 expression as well as a combination of CD16, CD56, or CD57. Abnormalities of other T-cell antigen expressions (especially CD5, CD7, and CD43) were also detected. In patients with polyclonal T-LGL lymphocytosis, T cells were dispersed in the bone marrow and the expression of pan-T-cell antigens in FCM was normal. Molecular studies revealed TCRB and TCRG gene rearrangements in 13 patients and TCRB, TCRG, and TCRD in 4 patients. The most frequently rearranged regions of variable genes were Vβ-Jβ1, Jβ2 and Vγ If Vγ10-Jγ. Moreover, in 4 patients, additional rearrangements of IG kappa and lambda variable genes of B cells were also observed.

Conclusion

RA and neutropenia patients represented a continuous spectrum of T-LGL proliferations, although monoclonal expansions were most frequently observed. The histopathological pattern and immunophenotype of bone marrow infiltration as well as molecular characteristics were similar in T-LGL leukemia patients with and without arthritis.  相似文献   
74.
HtrA2 belongs to the HtrA (high temperature requirement A) family of ATP-independent serine proteases. The primary function of HtrA2 includes maintaining the mitochondria homeostasis, cell death (by apoptosis, necrosis, or anoikis), and contribution to the cell signaling. Several recent reports have shown involvement of HtrA2 in development of cancer and neurodegenerative disorders. Here, we describe the profiling of HtrA2 protease substrate specificity via the combinatorial chemistry approach that led to the selection of novel intramolecularly quenched substrates. For all synthesized compounds, the highest HtrA2-mediated hydrolysis efficiency and selectivity among tested HtrA family members was observed for ABZ-Ile-Met-Thr-Abu-Tyr-Met-Phe-Tyr(3-NO2)-NH2, which displayed a specificity constant kcat/KM value of 14,535 M−1 s−1.  相似文献   
75.
We have elaborated a method which has allowed us to estimate the direction of translocation of orthologs which have changed, during the phylogeny, their positions on chromosome in respect to the leading or lagging role of DNA strands. We have shown that the relative number of translocations which have switched positions of genes from the leading to the lagging DNA strand is lower than the number of translocations which have transferred genes from the lagging strand to the leading strand of prokaryotic genomes. This paradox could be explained by assuming that the stronger mutation pressure and selection after inversion preferentially eliminate genes transferred from the leading to the lagging DNA strand. Received: 12 December 2000 / Accepted: 20 April 2001  相似文献   
76.
Variation in the growth patterns of roach, Rutilus rutilus (L.), pike, Esox lucius L., and chub, Leuciscus cephalus (L.) was examined along the upper Warta River, where human impact (mostly pollution) has influenced the longitudinal zonation on the fish assemblage. Significant differences were found in the exponent of weight-length relationships for roach and chub populations occupying different zones of the river, but no such variation was observed in pike. Moreover, pike growth was isometric, whereas roach and chub grew allometrically, with regression coefficients (slope) above 3. Although the length-at-age data were similar for each zone, the von Bertalanffy parameters (L inf, K and t 0) suggest that there may exist some inter-zone variation in the overall growth patterns of these species. All the species grew better in the zone where the index of relative abundance (relating dominance of a particular species to its maximum abundance in river system) achieved its highest value. The results suggest that a relative abundance index expressed in this way can be a good index of habitat quality.  相似文献   
77.
 Double-labelling immunofluorescence was used to investigate the coexistence of the catecholamine-synthesising enzymes, tyrosine hydroxylase and dopamine-β-hydroxylase and several neuropeptides including neuropeptide Y, vasoactive intestinal polypeptide, Leu5-enkephalin, somatostatin, calcitonin gene-related peptide and substance P in nerve fibres supplying the vas deferens in juvenile and adult pigs. The study has revealed three major populations of nerve terminals innervating the organ: (1) noradrenergic fibres; (2) non-noradrenergic (putative cholinergic) fibres containing vasoactive intestinal polypeptide, neuropeptide Y and somatostatin, supplying almost exclusively the lamina propria; and (3) non-noradrenergic, presumably sensory fibres, containing calcitonin gene-related peptide and substance P. The population of noradrenergic nerves can be divided into three subpopulations: a somatostatin-containing, a Leu5-enkephalin-containing and a subpopulation immunonegative to the peptides investigated, in descending order of magnitude. Coexistence patterns of the substances existing within nerve fibres supplying the vas deferens blood vessels are clearly different from those found in nerve fibres innervating the organ wall. The majority of the noradrenergic fibres associated with blood vessels contain neuropeptide Y only, while non-noradrenergic perivascular nerves contain predominantly vasoactive intestinal polypeptide. The possibility of different sources of origin of the particular nerve fibre subpopulations supplying the porcine vas deferens and its blood vessels is discussed. Accepted: 23 October 1996  相似文献   
78.
79.
The MICs and MBCs of quinupristin/dalfopristin were determined for 22 clinical strains MRSA with inducible type of resistance to MLS-B and for 15 of their derivatives with constitutive resistance to MLS-B. For MRSA strains with inducible resistance to MLS-B the obtained results for quinupristin/ dalfopristin were: MIC50 = 0.25, MIC90 = 0.5, MBC50 = 1.0 and MBC90 = 1.0. Mutants of the same strains characterized with the following values for quinopristin/dalfopristin: MIC50 = 0.5, MIC90 = 1.5, MBC50 = 4.0 and MTC90 = 8.0.  相似文献   
80.

Background

Arginine-specific (RgpB and RgpA) and lysine-specific (Kgp) gingipains are secretory cysteine proteinases of Porphyromonas gingivalis that act as important virulence factors for the organism. They are translated as zymogens with both N- and C-terminal extensions, which are proteolytically cleaved during secretion. In this report, we describe and characterize inhibition of the gingipains by their N-terminal prodomains to maintain latency during their export through the cellular compartments.

Methods

Recombinant forms of various prodomains (PD) were analyzed for their interaction with mature gingipains. The kinetics of their inhibition of proteolytic activity along with the formation of stable inhibitory complexes with native gingipains was studied by gel filtration, native PAGE and substrate hydrolysis.

Results

PDRgpB and PDRgpA formed tight complexes with arginine-specific gingipains (Ki in the range from 6.2 nM to 0.85 nM). In contrast, PDKgp showed no inhibitory activity. A conserved Arg-102 residue in PDRgpB and PDRgpA was recognized as the P1 residue. Mutation of Arg-102 to Lys reduced inhibitory potency of PDRgpB by one order of magnitude while its substitutions with Ala, Gln or Gly totally abolished the PD inhibitory activity. Covalent modification of the catalytic cysteine with tosyl-l-Lys-chloromethylketone (TLCK) or H-D-Phe-Arg-chloromethylketone did not affect formation of the stable complex.

Conclusion

Latency of arginine-specific progingipains is efficiently exerted by N-terminal prodomains thus protecting the periplasm from potentially damaging effect of prematurely activated gingipains.

General significance

Blocking progingipain activation may offer an attractive strategy to attenuate P. gingivalis pathogenicity.  相似文献   
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