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排序方式: 共有707条查询结果,搜索用时 15 毫秒
701.
Fabiola E. Villanova Enrico Andrade lcio Leal Priscila M. Andrade Ricardo C. Borra Lanfranco R.P. Troncone Leandro Magalhes Katia R.M. Leite Mario Paranhos Joaquim Claro Miguel Srougi 《Toxicon》2009,54(6):793-801
The peptides Tx2-5 and Tx2-6, isolated from the whole venom of “armed-spider” Phoneutria nigriventer venom, are directly linked with the induction of persistent and painful erection in the penis of mammals. The erection induced by Tx2-6 has been associated with the activation of nitric oxide synthases. There is a scarcity of studies focusing on the outcome of Tx2-6 at the molecular level, by this reason we evaluated the gene profile activity of this toxin at the nitric oxide (NO) pathway. After microarray analyses on cavernous tissue of mice inoculated with Tx2-6 we found that only 10.4% (10/96) of these genes were differentially expressed, showing a limited effect of the toxin on the NO pathway. We found the genes sparc, ednrb, junb, cdkn1a, bcl2, ccl5, abcc1 over-expressed and the genes sod1, s100a10 and fth1 under-expressed after inoculation of Tx2-6. The differential expressions of sparc and ednrb genes were further confirmed using real-time PCR. Interestingly, ednrb activates the l-arginine/NO/cGMP pathway that is involved in the relaxation of the cavernous body. Therefore the priapism induced by Tx2-6 is a consequence of a highly specific interference of this neurotoxin with the NO pathway. 相似文献
702.
G Merino R Real MF Baro L Gonzalez-Lobato JG Prieto AI Alvarez MM Marques 《Drug metabolism and disposition》2009,37(1):5-9
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates. 相似文献
703.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献704.
Gai M Motta D Giunti S Maddalena E Messina M Lasaponara F Lanfranco G Segoloni GP 《Journal of nephrology》2007,20(1):94-98
Microscopic sediment analysis of urine from a 56-year-old woman who underwent renal transplantation showed many uncommon clusters of rounded and translucent cells containing globular mucous cytoplasmic inclusions (HPF, x400). These cells were bigger than leukocytes and, compared with uroepithelial cells, showed a smaller nucleus to cytoplasm ratio and appeared eosinophilic, being pink rather than azurophilic with Sternheimer-Malbin stain. They were also unlikely to be tubular cells, which are usually smaller, singly distributed and associated with dysmorphic erythrocytes and/or casts and/or a worsening in renal function. A review of the patient's history showed that a pretransplantation urologic surgical treatment, including ileal bladder reconstruction, had been performed. Intestinal epithelial cells should be remembered when examining urinary sediment. 相似文献
705.
Andreani A Burnelli S Granaiola M Leoni A Locatelli A Morigi R Rambaldi M Varoli L Calonghi N Cappadone C Farruggia G Zini M Stefanelli C Masotti L 《Journal of medicinal chemistry》2007,50(14):3167-3172
The synthesis and antitumor activity of new E-3-(2-chloro-3-indolylmethylene)1,3-dihydroindol-2-ones is described. They were studied at the National Cancer Institute, taking into consideration the 50% growth inhibitory power (pGI50), the cytostatic effect (pTGI = total growth inhibition), and the cytotoxic effect (pLC50). All the compounds were potent growth inhibitors, with mean pGI50 ranging from 5.26 to 7.72. They were also analyzed with NCI COMPARE algorithm. Further studies were dedicated to the effects on the cell cycle and apoptosis. 相似文献
706.
707.
E. Baldini C. Tibaldi A. Ardizzoni F. Salvati A. Antilli L. Portalone S. Barbera F. Romano F. De Marinis M. R. Migliorino M. A. Noseda U. Borghini M. Crippa G. Ferrara M. Raimondi M. Fioretti M. Bandera M. C. Pennucci G. Galeasso G. C. Cacciani G. Lepidini G. Sunseri C. Lanfranco M. Rinaldi R. Rosso et al. 《British journal of cancer》1998,77(12):2367-2370
In the present multicentre randomized phase II trial, the activity and toxicity of three platinum-based combination regimens for the treatment of advanced non-small-cell lung cancer (NSCLC) were evaluated. The three regimens were: MVP (mitomycin-C 6 mg m(-2) on day 1, vindesine 3 mg m(-2) on days 1 and 15, and cisplatin 80 mg m(-2) on day 1 every 28 days), PIN (cisplatin 80 mg m(-2) day 1, ifosfamide 3 g m(-2) day 1 and vinorelbine 25 mg m(-2) day 1 and 8 every 21 days) and CaN (carboplatin 350 mg m(-2) day 1 and vinorelbine 25 mg m(-2) days 1 and 8 every 28 days). A total of 140 chemotherapy-naive patients entered the study; 49 patients were treated with MVP, 48 with PIN and 43 with CaN. Sixty-seven per cent of the patients had stage IV disease. Response rates, calculated on an ''intention to treat'' basis, were as follows: MVP, 14.3% (95% CI 5.94-27.2%); PIN, 16.7% (95% CI 7.4-30.2%); and CaN, 14% (95% CI 5.3-27.9%). The overall median survivals were 256, 269 and 243 days for patients treated with MVP, PIN and CaN respectively. Myelosuppression was the most frequent toxicity: grade 3-4 leucopenia was observed in 14.3%, 25% and 18.6% of patients treated with MVP, PIN and CaN respectively. This multicentre phase II randomized trial shows that MVP, PIN and CaN can be administered on an outpatient basis with acceptable toxicities. Unfortunately, the three regimens showed an activity significantly lower than that reported in previous single-institution phase II trials. 相似文献