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排序方式: 共有1399条查询结果,搜索用时 9 毫秒
101.
Hegab AE Sakamoto T Saitoh W Nomura A Ishii Y Morishima Y Iizuka T Kiwamoto T Matsuno Y Massoud HH Massoud HM Hassanein KM Sekizawa K 《Biochemical and biophysical research communications》2005,329(4):1246-1252
It is recognized that genetic factors play a role in the susceptibility to COPD. COPD is characterized by airflow limitation. Chronic inflammation causes small airway disease and parenchymal destruction, leading to the airflow limitation. Polymorphisms in pro-inflammatory cytokine genes may confer a risk for the development of COPD. A case-control association study was performed in Japanese population (88 COPD patients and 61 controls) and Egyptian population (106 patients and 72 controls). Genotype and allele frequencies of the TNFalpha -308 G/A and +489 G/A polymorphisms, the IL1beta -511 C/T, -31 T/C, and +3954 C/T polymorphisms, and a VNTR polymorphism in intron 2 of the IL1RN gene were investigated. In addition, pairwise haplotype frequencies were analyzed. When studied independently, none of the polymorphisms were associated with the development of COPD in both populations. However, in the Egyptian population, the distributions of the haplotype (IL1beta -31 T/C : IL1beta +3954 C/T) were significantly different between the COPD patients and the controls (p(corr)=0.0037). Our findings suggest that this haplotype within the IL1beta gene may be involved in the pathogenesis of COPD and that the genetic factors of COPD susceptibility might be different between different populations. 相似文献
102.
Hasan A Khan KM Sher M Maharvi GM Nawaz SA Choudhary MI Atta-ur-Rahman Supuran CT 《Journal of enzyme inhibition and medicinal chemistry》2005,20(1):41-47
A series of variably substituted chalcones were synthesized by condensation of substituted acetophenones with mono-, di- or trisubstituded benzaldehydes. It was observed that some of these compounds have the potential to inhibit acetylcholinesterase, whereas others show activity against butyrylcholinesterase, depending on the substitution pattern at the two aromatic rings of these chalcones. Similarly, lipoxygenase was inhibited by two of these compounds. It has been observed that inhibition of the three enzymes was concentration dependent with the IC50 values ranging from 28.2-134.5 microM against acetylcholinesterase, 16.0-23.1 microM against butyrylcholinesterase and 57.6-71.7 microM against lipoxygenase, respectively. 相似文献
103.
Alkharfy KM Khan RM Al-Hadiya BM Abou-Auda HS Abou-Shaaban RR 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,817(2):183-186
Abouthiouzine is a newly synthesized antithyroid agent with a proposed less adverse effects profile than other currently used drugs. A simple and rapid reversed phase high performance liquid chromatography assay was developed to determine the concentration of abouthiouzine in human plasma. The procedure involved extraction of the drug and propranolol (internal standard) from the plasma using ethylacetate. The extract was evaporated under nitrogen and the residue was constituted with the mobile phase and injected onto micro-Bondapack phenyl column (10 microm, 3.9 mm x 150 mm). The mobile phase consisted of 10 mM potassium dihydrogen phosphate buffer, acetonitrile, and methanol in the ratio of 60:25:15 (v/v/v, pH=3.0), which was delivered at a rate of 1.5 ml/min. Abouthiouzine and the internal standard were monitored using UV detection at 240 nm; the run time was less than 5 min. The detection limit of abouthiouzine is 0.5 microg/ml. The within- and between-day coefficients of variation were less than 7%. Our method has been successfully used to measure abouthiouzine plasma concentrations in a rabbit model following an intravenous administration of the drug. 相似文献
104.
Szemraj J Al-Nedawi KN Chabielska E Buczko W Pawlowska Z 《Acta biochimica Polonica》2005,52(4):849-855
The inhibitory effect of numerous analogues of PO-16, an hexadecadeoxyribonucleotide antisense to sequences -22 to -17 of PAI-1 mRNA coding for a fragment of the signal peptide, on the expression of PAI-1 in endothelial cells, and physiological consequences of the subsequently reduced PAI-1 activity tested in vitro and in vivo, were described in our previous studies. Of particular interest was PO-16 5'-O-conjugated with menthyl phosphorothioate (MPO-16R). In this work, tissue localisation of MPO-16R labelled with [(35)S] phosphorothioate at the 3'-end, was determined. [(35)S]MPO-16R and control [(35)S]MPO-16R-SENSE oligonucleotides were administered intravenously into 22 rats and organ distribution of the labelled bioconjugates was assessed after 24 and 48 h. For this purpose, tissue sections were subjected to autoradiography, and quantitated by liquid scintillation after solubilisation. Overall clearance of radioactivity was already seen after 24 h, with the radioactivity recovered mainly in the kidney and liver. A smaller fraction of radioactivity was also retained in the spleen and heart. The kidney concentration of the labelled probe was higher than that of liver by 50%. The distribution of PAI-1 mRNA in untreated rat kidney, liver, spleen and heart established by two independent techniques: Ribonuclease Protection Assay and Real-Time PCR, shows the same pattern as that observed for [(35)S]MPO-16R antisense. 相似文献
105.
Gong CX Liu F Wu G Rossie S Wegiel J Li L Grundke-Iqbal I Iqbal K 《Journal of neurochemistry》2004,88(2):298-310
Protein phosphatase 5 (PP5) is a 58-kDa novel phosphoseryl/phosphothreonyl protein phosphatase. It is ubiquitously expressed in all mammalian tissues examined, with a high level in the brain, but little is known about its physiological substrates. We found that this phosphatase dephosphorylated recombinant tau phosphorylated with cAMP-dependent protein kinase and glycogen synthase kinase-3beta, as well as abnormally hyperphosphorylated tau isolated from brains of patients with Alzheimer's disease. The specific activity of PP5 toward tau was comparable to those reported with other protein substrates examined to date. The PP5 activity toward tau was stimulated by arachidonic acid by 30- to 45-fold. Immunostaining demonstrated that PP5 was primarily cytoplasmic in PC12 cells and in neurons of postmortem human brain tissue. A small pool of PP5 associated with microtubules. Expression of active PP5 in PC12 cells resulted in reduced phosphorylation of tau, suggesting that PP5 can also dephosphorylate tau in cells. These results suggest that PP5 plays a role in the dephosphorylation of tau and might be involved in the molecular pathogenesis of Alzheimer's disease. 相似文献
106.
107.
Effect of post-mating GnRH analogue (buserelin) treatment on PGF2alpha release in ewes and ewe lambs
The objectives of this study were to determine the effects of buserelin or saline treatment on ovarian function (Experiment 1), plasma PGFM concentrations and oxytocin stimulated prostaglandin F(2alpha) (PGF(2alpha)) release (Experiment 2) in ewe lambs and ewes. Welsh Halfbred ewes (n=26) and ewe lambs (n=24) were mated to vasectomised rams at synchronised oestrus and on Day 12 post-mating each animal was injected intramuscularly either normal saline or 4 microg buserelin. In Experiment 1, plasma progesterone and oestradiol concentrations were determined in samples collected by jugular venepuncture 1h before and at 0, 2, 4, 6, 8, 24, 48 and 72 h after treatment (n=7 per treatment group). Progesterone concentrations increased (P<0.05) from 2 to 8h after buserelin treatment and returned to basal levels after 72 h, whereas oestradiol concentrations were maximal at 2h post-treatment and returned to basal levels after 24h (P<0.05). Oestradiol concentrations were lower (P<0.05) in buserelin-treated animals than controls at 72 h post-treatment. Basal and post-treatment progesterone concentrations were greater (P<0.05) in ewes than in ewe lambs but oestradiol levels were similar for both age groups. Ovulation rate, determined by laparoscopy on Day 14, was similar for both age groups (ewes 1.1; ewe lambs 1.0). Buserelin treatment induced accessory corpora lutea in ewes (4/7; 57%) but not in ewe lambs (0/7; 0%). In the Experiment 2, plasma PGFM concentrations were determined in samples collected at 20-min intervals for 6h on Day 14 and at 20-min intervals for 1h before and at 10-min intervals for 1h and then at 20-min intervals for a further 3h period after an intravenous injection of oxytocin (1IU/kg body weight) on Day 15 post-oestrus. In this experiment there were five ewe lambs and six ewes per treatment group. There was no effect of buserelin treatment or age on basal PGFM concentrations on either Day 14 or 15. Although peak PGFM concentrations tended to be lower in buserelin-treated animals, the difference was not significant (P>0.05). However, peak duration following oxytocin challenge on Day 15 post-mating was shorter (P<0.05) in control ewes compared with control ewe lambs. In conclusion, buserelin treatment given on Day 12 post-oestrus enhances luteal function more in ewes than ewe lambs and after a transitory increase, reduces oestradiol concentrations in both ewes and ewe lambs. However, buserelin treatment does not significantly attenuate the luteolytic signal. 相似文献
108.
Raza ZA Khan MS Khalid ZM Rehman A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(1-2):87-94
The present investigation dealt with the use of previously isolated and studied gamma-ray mutant strain Pseudomonas aeruginosa EBN-8 for the production of biosurfactant by using different hydrocarbon substrates viz. n-hexadecane, paraffin oil and kerosene oil, provided in minimal medium, as the sole carbon and energy sources. The batch experiments were conducted in 250 mL Erlenmeyer flasks, containing 50 mL minimal salt media supplemented with 1% (w/v) hydrocarbon substrate, inoculated by EBN-8 and incubated at 37 degrees C and 100 rpm in an orbital shaker. The sampling was done on 24 h basis for 10 d. The surface tension of cell-free culture broth decreased from 53 to 29 mN/m after 3 and 4 d of incubation when the carbon sources were paraffin oil and n-hexadecane, respectively. The largest reduction in interfacial tension from 26 to 0.4 mN/m was observed with n-hexadecane, while critical micelle dilution was obtained as 50 x CMC for paraffin oil as carbon source. When grown on n-hexadecane and paraffin oil, the EBN-8 mutant strain gave 4.1 and 6.3 g of the rhamnolipids/L, respectively. These surface-active substances subsequently allowed the hydrocarbon substrates to disperse readily as emulsion in aqueous phase. 相似文献
109.
Survival of the ectomycorrhizal fungal strain Suillus collinitus Sc-32 on Pinus halepensis after inoculation and outplanting was monitored in a Mediterranean plantation. Three molecular fingerprints were developed: RFLP of the internal transcribed spacer ribosomal DNA, intersimple sequence repeat, and a specific sequence-characterized amplified region marker. The inoculant was demonstrated to survive on inoculated seedlings 4 years after outplanting (56 months after inoculation), although S. collinitus was not fruiting. The designed markers set allows reliable and inexpensive monitoring of inoculated seedlings and suggests that S. collinitus is suitable for inoculation of Mediterranean Pinus. These data are discussed in the framework of suilloid population ecology. 相似文献
110.
Environmental samples were collected from high-pH sites in Pakistan, including a uranium heap set up for carbonate leaching,
the lime unit of a tannery, and the Khewra salt mine. Another sample was collected from a hot spring on the shore of the soda
lake, Magadi, in Kenya. Microbial cultures were enriched from Pakistani samples. Phylogenetic analysis of isolates was carried
out by sequencing 16S rRNA genes. Genomic DNA was amplified by polymerase chain reaction using integron gene-cassette–specific
primers. Different gene-cassette–linked genes were recovered from the cultured strains related to Halomonas magadiensis, Virgibacillus halodenitrificans, and Yania flava and from the uncultured environmental DNA sample. The usefulness of this technique as a tool for gene mining is indicated. 相似文献