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71.

Background

Calcium oxalate (CaOx) is the major constituent of about 75% of all urinary stone and the secondary hyperoxaluria is a primary risk factor. Current treatment options for the patients with hyperoxaluria and CaOx stone diseases are limited. Oxalate degrading bacteria might have beneficial effects on urinary oxalate excretion resulting from decreased intestinal oxalate concentration and absorption. Thus, the aim of the present study is to examine the in vivo oxalate degrading ability of genetically engineered Lactobacillus plantarum (L. plantarum) that constitutively expressing and secreting heterologous oxalate decarboxylase (OxdC) for prevention of CaOx stone formation in rats. The recombinants strain of L. plantarum that constitutively secreting (WCFS1OxdC) and non-secreting (NC8OxdC) OxdC has been developed by using expression vector pSIP401. The in vivo oxalate degradation ability for this recombinants strain was carried out in a male wistar albino rats. The group I control; groups II, III, IV and V rats were fed with 5% potassium oxalate diet and 14th day onwards group II, III, IV and V were received esophageal gavage of L. plantarum WCFS1, WCFS1OxdC and NC8OxdC respectively for 2-week period. The urinary and serum biochemistry and histopathology of the kidney were carried out. The experimental data were analyzed using one-way ANOVA followed by Duncan’s multiple-range test.

Results

Recombinants L. plantarum constitutively express and secretes the functional OxdC and could degrade the oxalate up to 70–77% under in vitro. The recombinant bacterial treated rats in groups IV and V showed significant reduction of urinary oxalate, calcium, uric acid, creatinine and serum uric acid, BUN/creatinine ratio compared to group II and III rats (P < 0.05). Oxalate levels in kidney homogenate of groups IV and V were showed significant reduction than group II and III rats (P < 0.05). Microscopic observations revealed a high score (4+) of CaOx crystal in kidneys of groups II and III, whereas no crystal in group IV and a lower score (1+) in group V.

Conclusion

The present results indicate that artificial colonization of recombinant strain, WCFS1OxdC and NC8OxdC, capable of reduce urinary oxalate excretion and CaOx crystal deposition by increased intestinal oxalate degradation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-014-0086-y) contains supplementary material, which is available to authorized users.  相似文献   
72.
73.
International Journal of Peptide Research and Therapeutics - The methicillin-resistant Staphylococcus aureus (MRSA) causes serious health problems such as community-acquired infections and...  相似文献   
74.
We report the creation of a new low-estrogen murine model of concurrent oral and vaginal C. albicans colonization that resembles human candidal carriage at both mucosal sites. Weekly estrogen administration of 5 microg intramuscular and subcutaneously was optimal for enhancement of oral colonization and was essential for vaginal colonization. In BALB/c mice, a number of C. albicans clinical isolates (n=3) colonized both oral and/or vaginal sites, but only strain 529L colonized 100% of mice persistently for over 5 weeks. Laboratory strains SC5314 and NCPF 3153 did not colonize the model; however, NCPF 3156 showed vaginal colonization up to week 5. Prior passaging through mice enhanced subsequent colonization of SC5314. Intranasal immunization with a C. albicans virulence antigen (secreted aspartyl proteinase 2) significantly reduced or abolished the fungal burden orally and vaginally by week 2 and 7. Our concurrent model of mucosal colonization reduces the numbers of experimental mice by half, can be used to assess potential vaccine candidates, and permits the detailed analysis of host-fungal interactions during the natural state of Candida colonization.  相似文献   
75.
Athletic performance is an important criteria used for the selection of superior horses. However, little is known about exercise-related epigenetic processes in the horse. DNA methylation is a key mechanism for regulating gene expression in response to environmental changes. We carried out comparative genomic analysis of genome-wide DNA methylation profiles in the blood samples of two different thoroughbred horses before and after exercise by methylated-DNA immunoprecipitation sequencing (MeDIP-Seq). Differentially methylated regions (DMRs) in the pre-and post-exercise blood samples of superior and inferior horses were identified. Exercise altered the methylation patterns. After 30 min of exercise, 596 genes were hypomethylated and 715 genes were hypermethylated in the superior horse, whereas in the inferior horse, 868 genes were hypomethylated and 794 genes were hypermethylated. These genes were analyzed based on gene ontology (GO) annotations and the exercise-related pathway patterns in the two horses were compared. After exercise, gene regions related to cell division and adhesion were hypermethylated in the superior horse, whereas regions related to cell signaling and transport were hypermethylated in the inferior horse. Analysis of the distribution of methylated CpG islands confirmed the hypomethylation in the gene-body methylation regions after exercise. The methylation patterns of transposable elements also changed after exercise. Long interspersed nuclear elements (LINEs) showed abundance of DMRs. Collectively, our results serve as a basis to study exercise-based reprogramming of epigenetic traits.  相似文献   
76.

The decolourization of the azo dye (acid yellow) by laccase from Bacillus sp. strain TR under submerged fermentation (SmF) was optimized by response surface methodology (RSM). The laccase maximum yield was achieved at 96 h of SmF with pH 7.0, 1.0 g/L of maltose and 3.0 g/L of ammonium acetate at 37 °C. The enzyme yield was estimated that 570 U/mL. About 76.4% of acid yellow decolourization efficiency was observed by the laccase enzyme within 96 h. The substrate surface changes were observed before and after the laccase treatment was analyzed with the scanning electron microscope (SEM) and N?=?N transformation either nitrogen or ammonia was showed by Fourier transform infrared spectroscopy (FT-IR) analysis. The HPLC analysis explained the formation of various intermediates in the conversion of acid yellow to final products. Further, in silico studies proved the enzyme–substrate interactions and showed a better score of ??27.435 kJ/mol.

  相似文献   
77.
New thiazolothiazole‐dithienosilole copolymer semiconductors bearing side chains of different type, size, and topology were synthesized and used to demonstrate the influence of side chains on morphology, charge transport and photovoltaic properties. The field effect mobility of holes varied from 0.01‐0.03 cm2V?1s?1 in PSOTT and PSEHTT to 0.12 cm2V?1s?1 in PSOxTT. The average power conversion efficiency of solar cells under 1.0 sun illumination could be varied from 2.1% in PSOxTT and 4.1% in PSOTT to 5.0% in PSEHTT. The highest photovoltaic efficiency achieved in PSEHTT, that has all‐branched alkyl side chains and face‐on π‐stacking orientation, was corroborated by its enhanced charge photogeneration observed by transient absorption spectroscopy.  相似文献   
78.
This study was aimed to investigate the effect of Cyclosporin A administration on renal calcium oxalate binding under hyperoxaluric condition.Cyclosporin A administration or ammonium oxalate treatment increased calcium oxalate binding, which was further increased in kidney treated with cyclosporin A and ammonium oxalate together. The increase of calcium oxalate binding was associated with lipid peroxidation as well as with a concomitant decrease in total thiol in both rat and human kdiney homogenate.Cyclosporin A administration to hyperoxaluric rats resulted with increased calcium oxalate binding protein. However there was no change with specific activity of the protein.In conclusion, Cyclosporin A administration either to normal or hyperoxaluric rats is resulted with increased concentration of calcium oxalate binding protein as well as enhanced activity due to membrane lipid peroxidation.  相似文献   
79.
The function of lipid peroxidation and the anti-peroxidative enzymes of rat liver and kidney were investigated under hyperoxaluric and stone forming conditions. The experimental animals showed higher malondialdehyde content in liver and kidney than that of control. A significant increase in malondialdehyde release was observed in the experimental liver or kidney when incubated with either ferrous sulphate or hydrogen peroxide compared to that of control liver or kidney. Superoxide dismutase activity was not affected in the hyperoxaluric rats while there was a moderate increase in the stone forming rats when compared to control. Highly significant decrease in catalase activity was observed in both conditions in liver and kidney compared to control.  相似文献   
80.
Diurnal variation in hydrological variables and dissolved inorganic nutrients such as PO inf4 sup3– -P, N O inf2 sup– -N, NO inf3 sup– -N and NH inf4 sup+ -N were studied in three interconnected biotopes including freshwater, marine and mangrove brackish water of the Kakinada coastal zone, Andhra Pradesh. Samples were collected at intervals of 3 hours, for a period of 24 hours. In the marine environment salinity varied from 26 to 32 whereas in the mangrove waters it fluctuated from 12 to 20 and in both biotopes salinity showed bimodal type of oscillation. Dissolved oxygen content was high in the mangrove waters during day time but decreased rapidly during the night hours. In the marine environment POf4 p3–-P concentration varied from 0.345 to 1.195 g at l–1, NO inf3 sup– -N from 1.03 to 6.62 g at l–1 and NO inf2 sup– -N from 0.086 to 0.506 g at l–1. The highest and the lowest concentrations of PO inf4 sup3– -P, NO inf3 sup– -N, NO inf2 sup– -N recorded in the mangrove waters were 0.790 and 0.325 g at l–1, 7.10 and 1.60 g at l–1 and 0.278 and 0.060 g at l–1, respectively. The concentration of PO inf4 sup3– -P, NO inf3 sup– -N and NO inf2 sup– -N were high in the freshwater canal, the maximum and minimum values being 1.110 and 0.730 g at l–1, 26.40 and 9.98 g at l–1 and 0.520 and 0.252 g at l–1 respectively. The concentration of ammonia was relatively high in the mangrove water. Gross and net primary production in the mangrove water was 4 times higher than in the marine biotope. There was no export of dissolved nutrients from the mangrove environment to the adjacent marine waters.  相似文献   
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