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101.
Fraga C Blanco M Vigo E Segura C García-Caballero T Pérez-Fernández R 《Histochemistry and cell biology》2002,117(6):547-550
1,25-Dihydroxyvitamin D(3) through its receptor (vitamin D receptor; VDR) has important physiological effects such as calcium transport and cell growth and differentiation. Although the VDR is present in a variety of cell lines as well as in numerous tissues, including rat and human heart, no data are available about the presence of VDR in heart at different steps of rat life. In this study we evaluated the VDR expression using RT-PCR and immunohistochemical techniques in fetal (17, 18 and 20 gestational days), neonatal (4 and 8 days) and adult rat heart. Immunohistochemical techniques showed the VDR protein localisation in the nuclei of cardiac muscle fibres. Also, we demonstrated that VDR mRNA expression is changing over these different periods of development, showing significant differences in 20 days versus 18 days of fetal age. These changes in VDR expression may be related to other parameters associated with the development of the cardiac muscle and/or intracellular cardiac cell calcium homeostasis. 相似文献
102.
103.
Velasco A Román C Aragüés M Noguera X Ventura C Lerís E 《Revista iberoamericana de micología》2002,19(3):169-172
Different clinical studies have demonstrated flutrimazole's efficacy in the treatment of superficial dermatomycoses when administered either twice daily or once daily for four weeks. The aim of the present study was to compare both dosing schedules for the treatment of superficial dermatomycoses. In this randomized, controlled, double blind study, we included 84 patients suffering superficial dermatophytosis (confirmed by microscopic examination (KOH) and culture) susceptible for topical monotherapy. Forty-one patients received flutrimazole 1% twice daily (TD) and forty-three once daily (OD) for four weeks. The efficacy of treatment was evaluated by clinical and mycological criteria at the end of treatment (D28) and after four weeks without treatment (D58). Clinical and mycological cure rates on D28 were 50% with TD and 65% with OD treatment. Only considering clinical evaluation, clinical cure rates on D28 were 63% (TD) and 70% (OD). Also, clinical and mycological cure rates on D56 were 65% with TD and 72% with OD treatment. Only considering clinical evaluation, clinical cure rates on D56 were of 68% (TD) and 72% (OD). The overall tolerability was similar in both treatment groups. The efficacy assessment at the end of treatment (D28) and four weeks after treatment discontinuation (D56) showed that the OD treatment is not inferior to the TD treatment, with similar clinical and mycological cure rates and clinical cure rates in both cases. The OD administration of flutrimazole cream 1% is the most appropriate dosing schedule as it provides the same efficacy, it improves patient's compliance and the cost per day of treatment. 相似文献
104.
Raaijmakers H Macieira S Dias JM Teixeira S Bursakov S Huber R Moura JJ Moura I Romão MJ 《Structure (London, England : 1993)》2002,10(9):1261-1272
Desulfovibrio gigas formate dehydrogenase is the first representative of a tungsten-containing enzyme from a mesophile that has been structurally characterized. It is a heterodimer of 110 and 24 kDa subunits. The large subunit, homologous to E. coli FDH-H and to D. desulfuricans nitrate reductase, harbors the W site and one [4Fe-4S] center. No small subunit ortholog containing three [4Fe-4S] clusters has been reported. The structural homology with E. coli FDH-H shows that the essential residues (SeCys158, His159, and Arg407) at the active site are conserved. The active site is accessible via a positively charged tunnel, while product release may be facilitated, for H(+) by buried waters and protonable amino acids and for CO(2) through a hydrophobic channel. 相似文献
105.
Nociceptin-immunoreactive cellbodies were detected in the human trigeminal ganglion, while no such fibers were identified in the temporal artery or in dermal tissue from the neck region. In four healthy subjects receiving nociceptin into the temporal muscle in an open labeled design no pain was detected. In 10 healthy subjects who received 200pmol of nociceptin into tender non-dominant trapezius muscles in a placebo-controlled, randomized, balanced, and double-blinded design local tenderness increased (P=0.025) while no pain was noted. Thus, the action of nociceptin should be searched for in the trigeminal ganglion and/or in the central nervous system (CNS). 相似文献
106.
Haidari M Leung N Mahbub F Uffelman KD Kohen-Avramoglu R Lewis GF Adeli K 《The Journal of biological chemistry》2002,277(35):31646-31655
Insulin-resistant states are characterized by hypertriglyceridemia, predominantly because of overproduction of hepatic very low density lipoprotein particles. The additional contribution of intestinal lipoprotein overproduction to the dyslipidemia of insulin-resistant states has not been previously appreciated. Here, we have investigated intestinal lipoprotein production in a fructose-fed hamster model of insulin resistance previously documented to have whole body and hepatic insulin resistance, and hepatic very low density lipoprotein overproduction. Chronic fructose feeding for 3 weeks induced significant oversecretion of apolipoprotein B48 (apoB48)-containing lipoproteins in the fasting state and during steady state fat feeding, based on (a) in vivo Triton WR1339 studies of apoB48 production as well as (b) ex vivo pulse-chase labeling of intestinal enterocytes from fasted and fed hamsters. ApoB48 particle overproduction was accompanied by increased intracellular apoB48 stability, enhanced lipid synthesis, higher abundance of microsomal triglyceride transfer protein mass, and a significant shift toward the secretion of larger chylomicron-like particles. ApoB48 particle overproduction was not observed with short-term fructose feeding or in vitro incubation of enterocytes with fructose. Secretion of intestinal apoB48 and triglyceride was closely linked to intestinal enterocyte de novo lipogenesis, which was up-regulated in fructose-fed hamsters. Inhibition of fatty acid synthesis by cerulenin, a fatty acid synthase inhibitor, resulted in a dose-dependent decrease in intestinal apoB48 secretion. Overall, these findings further suggest that intestinal overproduction of apoB48 lipoproteins should also be considered as a major contributor to the fasting and postprandial dyslipidemia observed in response to chronic fructose feeding and development of an insulin-resistant state. 相似文献
107.
108.
Linares Sicilia MJ Santos Lacomba M Solís Cuesta F SánchezPedraza R Nievas Gómez T Casal Román M 《Revista iberoamericana de micología》2003,20(2):68-70
A case of Scedosporium apiospermum keratitis is reported in a 65-year-old farmer referred for treatment of an extensive corneal ulcer in the left eye. Direct examination of scrapes revealed abundant filamentous septate hyphae; all cultures were consistently positive for the same fungus, identified later as Scedosporium apiospermum. The patient successfully responded to treatment with amphotericin B. 相似文献
109.
Neo-clerodane diterpenoids from Croton schiedeanus 总被引:2,自引:0,他引:2
Puebla P López JL Guerrero M Carrón R Martín ML San Román L San Feliciano A 《Phytochemistry》2003,62(4):551-555
Two new neo-clerodane type furano diterpenoids were isolated from the aerial part of Croton schiedeanus, besides the clerodane diterpenes cis- and trans-dehydrocrotonin, previously isolated from other species of Croton. Structural elucidation was achieved on basis of extensive NMR experiments, including X-ray diffraction analysis and molecular mechanics calculations. The previously known flavonoids ayanin and quercetin-3,7-dimethyl ether were also obtained from the extract of this plant. 相似文献
110.
BACKGROUND: The incretin hormones GIP and GLP-1 are thought to be produced in separate endocrine cells located in the proximal and distal ends of the mammalian small intestine, respectively. METHODS AND RESULTS: Using double immunohistochemistry and in situ hybridization, we found that GLP-1 was colocalized with either GIP or PYY in endocrine cells of the porcine, rat, and human small intestines, whereas GIP and PYY were rarely colocalized. Thus, of all the cells staining positively for either GLP-1, GIP, or both, 55-75% were GLP-1 and GIP double-stained in the mid-small intestine. Concentrations of extractable GIP and PYY were highest in the midjejunum [154 (95-167) and 141 (67-158) pmol/g, median and range, respectively], whereas GLP-1 concentrations were highest in the ileum [92 (80-207) pmol/l], but GLP-1, GIP, and PYY immunoreactive cells were found throughout the porcine small intestine. CONCLUSIONS: Our results provide a morphological basis to suggest simultaneous, rather than sequential, secretion of these hormones by postprandial luminal stimulation. 相似文献