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排序方式: 共有9813条查询结果,搜索用时 15 毫秒
51.
Claudia Fumarola Mara A. Bonelli Pier Giorgio Petronini Roberta R. Alfieri 《Biochemical pharmacology》2014
While PI3K/AKT/mTOR pathway is altered in a variety of cancers including non small cell lung cancer, abnormalities in this pathway are more common in squamous cell lung carcinoma than in adenocarcinoma of the lung. Moreover, aberrant activation of PI3K/AKT/mTOR pathway is one of the mechanisms of acquired resistance to EGFR-TK inhibitors in patients with adenocarcinoma carrying EGFR activating mutations. 相似文献
52.
Roberta Cassano Teresa Ferrarelli Maria Vittoria Mauro Paolina Cavalcanti Nevio Picci 《Drug delivery》2016,23(3):1037-1046
The present article reports the preparation, characterization and performance evaluation of solid lipid nanoparticles (SLNs) based on polyoxyethylene-40 stearate (PEG-40 stearate) for the administration of antifungal agents such as ketoconazole and clotrimazole. These nanoparticles could be useful in the treatment of vaginal infections sustained by Candida albicans. In particular, PEG-40 stearate was made to react with acryloyl chloride in order to introduce an easily polymerizable moiety for the creation of a second shell and to ensure a slow drug release. In addition, the differences on the release profiles between PEG-40 stearate-based nanoparticles, PEG-40 stearate acrylate based and polymerized ones, were analyzed under conditions, simulating the typical environment of Candida albicans infection. Then, the antifungal activity of nanoparticles was also evaluated in terms of minimal inhibitory concentration. Moreover, the nanoparticles were submitted to in vitro studies for evaluating the drug permeability at the site of action. Results indicated that the obtained particles are potentially useful for the treatment of vaginal infections sustained by Candida albicans. 相似文献
53.
Lambertini E Piva R Khan MT Lampronti I Bianchi N Borgatti M Gambari R 《International journal of oncology》2004,24(2):419-423
54.
Roberto Orecchia Umberto Veronesi Patrick Maisonneuve Viviana Enrica Galimberti Roberta Lazzari Paolo Veronesi Barbara Alicja Jereczek-Fossa Federica Cattani Claudia Sangalli Alberto Luini Pietro Caldarella Marco Venturino Daniele Sances Stefano Zurrida Giuseppe Viale Maria Cristina Leonardi Mattia Intra 《The lancet oncology》2021,22(5):597-608
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Lee TK Wang W O'Brien KF Johnke RM Wang T Allison RR Diaz AL 《Phytotherapy research : PTR》2008,22(12):1614-1622
To explore the radioprotective effect of a standardized North American ginseng extract (NAGE) on human peripheral blood lymphocytes (PBL), a micronuclei (MN) assay was conducted in PBL obtained from 12 volunteers. NAGE (50-1000 microg/mL) and WR-1065 (1 mM and 3 mM) were applied to PBL cultures at 0 h and 90 min post-irradiation. It was found that (1) the baseline MN yield of PBL ranged from 14.4 +/- 1.5 to 15.9 +/- 1.5 per 1000 binucleated cells (p > 0.05); after irradiation (1 Gy and 2 Gy), the MN yield increased sharply; (2) MN yields declined with increasing concentrations of NAGE and WR-1065. Even at 90 min post-irradiation of 1 Gy, the maximum level of MN reduction rate caused by NAGE and WR-1065 was 53.8% and 59.2%, respectively; after 2 Gy irradiation, it was 37.3% and 42%, respectively; (3) the MN distribution in PBL followed a non-Poisson distribution in all cases; and (4) both NAGE and WR-1065 showed no significant effect on the proliferation index of lymphocytes. The results indicate that NAGE is a relatively non-toxic natural product, which can be administered as a dietary supplement and has the potential to be a radiation countermeasure. 相似文献
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OBJECTIVE: To assess the diagnostic test characteristics of placental weight as a clinical predictor of small-for-gestational-age (SGA) neonates. STUDY DESIGN: Placentas were weighed at 45,846 deliveries. Predictive values and likelihood ratios (LRs) were calculated assessing placental weight (lowest tertile vs. top 2 or mid/high tertiles) as a predictor of SGA both overall and by maternal age, gestational age, maternal weight, reported early pregnancy smoking, race, neonatal sex and parity. RESULTS: Although the positive predictive value (PPV) of low placental weight was poor (0.19), the negative predictive value (NPV) was high (0.97). Both NPV and LR- were powerfully predictive in women at earlier gestational ages. At gestational ages <32 weeks, LR-was 0.11, showing that among women with mid/high placental weight, the proportion with SGA (false negative) was about 1/10 that without SGA (true negative). CONCLUSION: Placental weight in the mid or upper tertile has strong NPV and LR- for delivery of an SGA neonate. Further study of the value of placental size in prediction of SGA is warranted. 相似文献
60.
The effect of various sulfonamide drugs on the electrocardiogram was studied in thirty-nine dogs.Sulfonamide administration had no effect upon the cardiac muscle and conducting system which could be demonstrated by the electrocardiogram in thirty-two dogs (82 per cent of the number studied), even though eleven of these dogs showed conduction defects before treatment.Electrocardiographic abnormalities consisting of slight S-T segment deviation and change in direction of T wave occurred in seven dogs during medication and indicated some myocardial involvement. These changes were transient and disappeared after drug administration was stopped in all except three cases. The possibility that these electrocardiographic changes were the result of morphologic changes in cardiac muscle caused by sulfonamide sensitization is discussed. 相似文献