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排序方式: 共有448条查询结果,搜索用时 15 毫秒
51.
Immune and autoimmune disorders in HCV chronic liver disease: personal experience and commentary on literature 总被引:3,自引:0,他引:3
Giordano N Amendola A Papakostas P Cipolli F Agate VM Battisti E Marchi B Nuti R 《The new microbiologica》2005,28(4):311-317
HCV chronic liver disease can be associated with a plethora of immune and autoimmune perturbations and many authors claim that HCV chronic infection can play an important role in the pathogenesis of these disorders. To compare our experience with literature reports, we performed a retrospective study on the case histories of 265 patients with HCV chronic liver disease, evaluating the type and prevalence of the associated immune and autoimmune manifestations. We found that the patients with HCV chronic liver disease can present arthromyalgias (7.1% of the patients), Sj?rgen's syndrome (5.2%), thyroiditis (4.1%), rheumatoid arthritis (2.2%), autoimmune thrombocytopenia (2.6%), mixed cryoglobulinemia (1.5%), autoimmune anemia (0.3%) and oral lichen planus (0.3%). We claim that HCV liver infection is able to induce immune and autoimmune perturbations, without playing a significant role in the pathogenesis of a well-defined disorder. 相似文献
52.
Vita M Skansen P Hassan M Abdel-Rehim M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,817(2):303-307
Roscovitine, a purine analogue that selectively inhibits cyclin-dependent kinases, has been considered as a potential anti-tumor drug. The determination of roscovitine in plasma and urine was performed using microextraction in packed syringe as on-line sample preparation method with liquid chromatography and tandem mass spectrometry. The sampling sorbent utilized was polystyrene polymer. 2H3-lidocaine was used as internal standard. The limit of detection for roscovitine was as low as 0.5 ng/mL and the lower limit of quantification was 1.0 ng/mL. The accuracy and precision values of quality control samples were between +/-15% and < or =11%, respectively. The calibration curve was obtained within the concentration range 0.5-2000 ng/mL in both plasma and urine. The regression correlation coefficients for plasma and urine samples were > or =0.999 for all runs. The present method is miniaturized and fully automated and can be used for pharmacokinetic and pharmacodynamic studies. 相似文献
53.
Vita M Abdel-Rehim M Nilsson C Hassan Z Skansen P Wan H Meurling L Hassan M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,821(1):75-80
In the present investigation, the binding of roscovitine (100, 500 and 1500 ng/mL) to plasma proteins was studied at 25 and 37 degrees C by ultrafiltration and equilibrium dialysis methods. Drug stability in plasma was assessed during a 48 h at 4, 25 and 37 degrees C. The effect of thawing and freezing on drug stability was studied. The pKa of roscovitine was measured using capillary electrophoresis coupled with mass spectrometry. Roscovitine was quantified utilizing liquid chromatography and tandem mass spectrometry. Roscovitine is highly bound to plasma proteins (90%). Binding of roscovitine to human serum albumin was constant (about 90%) within concentration range studied while the binding to alpha1-acid glycoprotein decreased with increasing drug concentration indicating that albumin is more important in clinical settings. However, alpha1-acid glycoprotein might be important when plasma proteins change with disease. Protein binding was higher at 25 degrees C compared to 37 degrees C. The results obtained by equilibrium dialysis were in good agreement with those obtained by ultrafiltration. Roscovitine was stable at all temperatures studied during 48 h. Roscovitine has a pKa of 4.4 showing that the drug mainly acts like a weak mono-base. The results obtained in our studies are important prior to clinical trials and to perform pharmacokinetic studies. 相似文献
54.
Sterol 14-demethylase (CYP51) is a member of the cytochrome P450 superfamily, widely found in animals, fungi, and plants but present in few prokaryotic groups. CYP51 is currently believed to be the ancestral cytochrome P450 that has been transferred from prokaryotes to eukaryotic kingdoms. We propose an alternate view of CYP51 evolution that has an impact on understanding the evolution of the entire CYP superfamily. Two hundred forty-nine bacterial and four archaeal CYP sequences have been aligned and a bacterial CYP tree designed, showing a separation of two branches. Prokaryotic CYP51s cluster to the minor branch, together with other eukaryote-like CYPs. Mycobacterial and methylococcal CYP51s cluster together (100% bootstrap probability), while Streptomyces CYP51 remains on a distant branch. A CYP51 phylogenetic tree has been constructed from 44 sequences resulting in a ((plant, bacteria),(animal, fungi)) topology (100% bootstrap probability). This is in accordance with the lanosterol/cycloartenol diversification of sterol biosynthesis. The lanosterol branch (nonphotosynthetic lineage) follows the previously proposed topology of animal and fungal orthologues (100% bootstrap probability), while plant and D. discoideum CYP51s belong to the cycloartenol branch (photosynthetic lineage), all in accordance with biochemical data. Bacterial CYP51s cluster within the cycloartenol branch (69% bootstrap probability), which is indicative of a lateral gene transfer of a plant CYP51 to the methylococcal/mycobacterial progenitor, suggesting further that bacterial CYP51s are not the oldest CYP genes. Lateral gene transfer is likely far more important than hitherto thought in the development of the diversified CYP superfamily. Consequently, bacterial CYPs may represent a mixture of genes with prokaryotic and eukaryotic origin. 相似文献
55.
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57.
The goal of this study was to determine the acute effects of permanent denervation on the length density of the capillary
network in rat slow soleus (SOL) and fast extensor digitorum longus (EDL) muscles and the effect of short-lasting reinnervation
in slow muscle only. Denervation was performed by cutting the sciatic nerve. Both muscles were excised 2 weeks later. Reinnervation
was studied 4 weeks after nerve crush in SOL muscle only. Capillaries and muscle fibres were visualised by triple immunofluorescent
staining with antibodies against CD31 and laminin and with fluorescein-labelled Griffonia (Bandeira) simplicifolia lectin. A recently developed stereological approach allowing the estimation of the length of capillaries adjacent to each
individual fibre (Lcap/Lfib) was employed. Three-dimensional virtual test grids were applied to stacks of optical images captured with a confocal microscope
and their intersections with capillaries and muscle fibres were counted. Interrelationships among capillaries and muscle fibres
were demonstrated with maximum intensity projection of the acquired stacks of optical images. The course of capillaries in
EDL seemed to be parallel to the fibre axes, whereas in SOL, their preferential direction deviated from the fibre axes and
formed more cross-connections among neighbouring capillaries. Lcap/Lfib was clearly reduced in denervated SOL but remained unchanged in EDL, although the muscle fibres significantly atrophied in
both muscle types. When soleus muscle was reinnervated, capillary length per unit fibre length was completely restored. The
physiological background for the different responses of the capillary network in slow and fast muscle is discussed.
This study was supported by the Slovenian Research Agency and the Ministry of Education, Youth and Sport of the Czech Republic
(KONTAKT grant no. 19/2005). 相似文献
58.
59.
A high-density consensus map of A and B wheat genomes 总被引:1,自引:0,他引:1
Daniela Marone Giovanni Laidò Agata Gadaleta Pasqualina Colasuonno Donatella B. M. Ficco Angelica Giancaspro Stefania Giove Giosué Panio Maria A. Russo Pasquale De Vita Luigi Cattivelli Roberto Papa Antonio Blanco Anna M. Mastrangelo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,125(8):1619-1638
A durum wheat consensus linkage map was developed by combining segregation data from six mapping populations. All of the crosses were derived from durum wheat cultivars, except for one accession of T. ssp. dicoccoides. The consensus map was composed of 1,898 loci arranged into 27 linkage groups covering all 14 chromosomes. The length of the integrated map and the average marker distance were 3,058.6 and 1.6?cM, respectively. The order of the loci was generally in agreement with respect to the individual maps and with previously published maps. When the consensus map was aligned to the deletion bin map, 493 markers were assigned to specific bins. Segregation distortion was found across many durum wheat chromosomes, with a higher frequency for the B genome. This high-density consensus map allowed the scanning of the genome for chromosomal rearrangements occurring during the wheat evolution. Translocations and inversions that were already known in literature were confirmed, and new putative rearrangements are proposed. The consensus map herein described provides a more complete coverage of the durum wheat genome compared with previously developed maps. It also represents a step forward in durum wheat genomics and an essential tool for further research and studies on evolution of the wheat genome. 相似文献
60.
Iaffaldano P Viterbo RG Paolicelli D Lucchese G Portaccio E Goretti B Direnzo V D'Onghia M Zoccolella S Amato MP Trojano M 《PloS one》2012,7(4):e35843