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排序方式: 共有2195条查询结果,搜索用时 312 毫秒
1.
Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
2.
A. Farina 《Journal of pharmaceutical and biomedical analysis》1989,7(12):1579-1583
A simple and rapid fluorimetric method for the determination of 9-fluoro-10-[N-(4′-methyl)piperazinyl]-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-d,e][1–4]benzothyazin-6-carboxylic acid hydrochloride (MF 934), in serum and in pharmaceutical formulations, has been developed based on its strong fluorescence, in 0.1 N H2SO4, at 526 nm (excitation wavelength at 340 nm). The procedure which involves the direct dilution of the sample requires only a few minutes and the sample volume is only 20–100 μl of serum, depending on the drug concentration. Tedious sample preparation procedures such as extraction, deproteinization, or centrifugation are not necessary. The minimum concentration that can be detected is 0.3 ng ml−1, the standard curve in 0.1 N H2SO4 was found to be linear from 0.005 to 1.5 μg ml−1 and from 0.01 to 0.07 g in plasma after dilution with 0.1 N H2SO4. 相似文献
3.
Roberto Farina M.D. 《Aesthetic plastic surgery》1987,11(1):249-253
Keratodermia is an incurable genetic and regional disease located in the palmar and plantar regions. The author reports his experience with five cases of palmoplantar keratodermia that were treated by grafting onto the soles and the palms skin taken from the calves and the thighs. 相似文献
4.
E Benfenati R Fanelli E Bosone R Caponi P Farina 《European journal of drug metabolism and pharmacokinetics》1992,17(2):93-101
The compound IBI-P-05006, 2-(6'-carboxyhexyl)-3-n-hexylcyclohexylamine, is an antiaggregating agent under development. IBI-P-05006 is an in vitro inhibitor of platelet aggregation. The biotransformation of this compound has been studied in the dog and rat. We present here a study on the metabolites of IBI-P-05006 found in dog and rat urine, and in dog plasma. Analyses were done by gas chromatography-mass spectrometry. In dog urine 15 metabolites were identified. Some of them were also found in dog plasma and in rat urine. The unmetabolized drug was found only in plasma. 10 different hydroxylated metabolites were characterized. The hydroxyl groups were introduced in the hexyl chain in positions omega-4, omega-3, omega-2, omega-1 and omega. 相似文献
5.
J Hasegawa R Matsuoka K Ichizuka A Sekizawa A Farina T Okai 《Ultrasound in obstetrics & gynecology》2006,27(4):425-429
OBJECTIVES: To evaluate the accuracy of sonographic identification of the site of umbilical cord insertion (CI) at 18-20 weeks of gestation, to compare the sensitivities for detection of a velamentous cord insertion (VCI) secondary to a CI into the anterior, posterior or fundal wall, and to compare the intrapartum complications secondary to VCI into the upper, middle or lower third of the uterus. METHODS: As part of the routine ultrasound scan at 18-20 weeks' gestation we evaluated abnormal CI (VCI and marginal CI) and the location of the CI in the uterus in 3446 pregnancies. In cases of abnormal CI, the location of the CI was further classified as being in the upper, middle or lower third of the uterus. After delivery, the placenta and the umbilical cord were examined and intrapartum complications were compared with the location of the CI. RESULTS: The values for antenatal detection of VCI were: sensitivity, 25 of 40 (62.5%); positive predictive value, 25 of 25 (100%); and negative predictive value, 3406 of 3421 (99.6%). The sensitivity for cases in which the CI was located on the anterior wall was 12 of 13 (92.3%); when it was located on the posterior wall, the sensitivity was 11 of 22 (50.0%); and when it was fundal the sensitivity was 2 of 5 (40.0%). Variable decelerations were frequently observed with a VCI. In lower VCI cases, non-reassuring fetal heart rate patterns and emergency Cesarean sections occurred with a higher frequency than in cases with upper or middle VCI (P < 0.01). After delivery, the length of the aberrant vessels in cases of VCI by pathologic examination was 3.9 +/- 3.3 cm in the upper third, 4.7 +/- 4.6 cm in the middle third, and 10.6 +/- 6.8 cm in the lower third; thus, the aberrant vessel length was significantly greater when the CI was in the lower third of the uterus (P = 0.024). CONCLUSION: We have demonstrated that VCI with a lower CI site and with longer aberrant vessels is associated with various intrapartum complications. This finding has the potential for improving perinatal outcome. 相似文献
6.
Toxic pustuloderma associated with azithromycin 总被引:1,自引:0,他引:1
7.
Naz M. Aghatabay A. Ba A. Kircali G. en M.B. Yaziciolu F. Gücin B. Dülger 《European journal of medicinal chemistry》2009,44(11):4681-4689
Series of new mixed aza-oxo-thia macrocyclic ligands 1,9(2,6)-ditriazina-2,8,10,16-tetraaza-3,7,11,15-tetraoxo-5,13-dithia-cyclohexadecaphan-14,94-diphenyl (L1); 1,10(2,6)-ditri azina-2,9,11,18-tetraaza-3,8,12,17-tetraoxo-5,6,14,15-tetrathia-cyclooctadecaphan-14,104-diphenyl (L2); 1,11(2,6)-ditriazina-2,10,12,20-tetraaza-3,9,13,19-tetraoxo-6,16-dithia-cyclocosa-phan-14,114-diphenyl (L3); 1,12(2,6)-ditriazina-2,11,13,22-tetraaza-3,10,14,21-tetraoxo-6,7,17,18-tetrathia-cyclodocosaphan-14,124-diphenyl (L4) were synthesised. The structural features of the compounds have been studied by elemental analyses, Mass, FT-Raman, FT-IR, 1H and 13C NMR spectroscopy. The antimicrobial activities of the ligands were evaluated using disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimal inhibitory concentration (MIC) dilution method, against several bacteria and yeast cultures. The obtained results from both methods were assessed in side-by-side comparison with commercial antibacterial and antifungal agents. In most cases, the compounds show strong antifungal activity in the comparison tests. Cytotoxic activities of the ligands against two different human cancer cell lines, stomach (23132/87) and lung (A549) were determined by MTT assay. DNA fragmentation assay tested cell lines were used to analyze the DNA ladder formation which is a characteristic of apoptotic cell death. The binding of the ligands with calf thymus DNA (CT-DNA) has also been investigated by absorption spectroscopy. 相似文献
8.
Emilio Benfenati Pierluigi Farina Tina Colombo Gianluca De Bellis Mauro Valerio Capodiferro Maurizio D'Incalci 《Cancer chemotherapy and pharmacology》1989,24(6):354-358
Summary The pharmacokinetics of the anticancer agent p-(3,3-dimethyl-1-triazeno) benzoic acid (pCOOH-DMT), a drug now in phase I clinical trial in Europe, was investigated in C57 Bl female mice with M5076 reticulum-cell sarcoma that were treated i.v. with 200 mg/kg pCOOH-DMT. The drug disappeared from plasma with a terminal half-life of about 2.5 h. Plasma clearance was approximately 6 ml/min per kg. Distribution studies showed some differences in drug levels in different tissues. The highest levels were found in the tumor, liver, kidney and lung; lower levels were found in the spleen and gut, and the lowest, in the brain. The N-desmethyl derivative of pCOOH-DMT was not detectable in plasma or tissues of mice treated with the drug. Therefore, the previous evidence of low N-demethylation of pCOOH-DMT was confirmed. pCOOH-DMT glucuronide was identified by mass spectrometry and quantified by high-performance liquid chromatography (HPLC) in plasma, tissues and urine samples. pCOOH-DMT glucuronide appears to be the major urinary metabolite of pCOOH-DMT in mice. Another metabolite identified by mass spectrometry and quantified by HPLC in some tissues and urine was pCOOH-DMT glycinate.Abbreviations DTIlC
5-(3,3-dimethyl-l-triazeno)imidazole-4-carboxamide
- pCOOH-DMT
p-(3,3-dimethyl-l-triazeno)benzoic acid
- pCOOH-MMT
p-(3-methyl-l-triazeno)benzoic acid
- pCONH2-DMT
p-(3,3-dimethyl-l-triazeno)carboxamide
- BSTFA
N,O-bis(trimethylsilyl)trifluoroacetamide
- TMCS
trimethylchlorosilane
- TLC
thin-layer chromatography
- FAB
fast atom bombardment
- EI
electron impact
- M5
M5076 reticulum-cell sarcoma
- t1/2
beta-half-life
- C0
concentration time 0
- AUC
area under the concentration vs time curve
- Cl
total clearance
- V
volume of distribution 相似文献
9.
CD1a and antitumour immune response 总被引:3,自引:0,他引:3
Primary immune response is based on the capacity of local professional antigen-presenting cells (whose prototype is represented by dendritic cells, DCs) to take up and present antigens to selected clones of T cells, but also to non-specific effector cells such as macrophages or natural killer cells. The four CD1 proteins, all of which share a limited homology to class I MHC proteins, are differently expressed in various cell types, of both mesenchymal and, as recently described, epithelial lineage. Regarding the role of CD1 molecules in the anti-tumour response, it has been reported that CD1+ dendritic cells are involved in the first steps of the primary immune response in a number of malignancies. Moreover, the presence of a high number of DCs in the tumoral or peritumoral area, as well as in the draining lymph nodes, has been shown to correlate with a better prognosis. A recent report on the presence of CD1a in metaplastic epithelial cells of Barrett esophagus introduced new questions about CD1a expression patterns. Moreover, the strong correlation between the lack of CD1a+ cells and the malignant evolution of the lesion may indicate a possible role of non-professional APCs in mediating and/or potentiating immune responses to tumours. 相似文献
10.
Maitrot A Lucas MF Doncarli C Farina D 《Medical & biological engineering & computing》2005,43(4):487-492
In the study, an efficient method to perform supervised classification of surface electromyogram (EMG) signals is proposed.
The method is based on the choice of a relevant representation space and its optimisation with respect to a training set.
As EMG signals are the summation of compact-support waveforms (the motor unit action potentials), a natural tool for their
representation is the discrete dyadic wavelet transform. The feature space was thus built from the marginals of a discrete
wavelet decomposition. The mother wavelet was designed to minimise the probability of classification error estimated on the
learning set (supervised classification). As a representative example, the method was applied to simulate surface EMG signals
generated by motor units with different degrees of short-term synchronisation. The proposed approach was able to distinguish
surface EMG signals with degrees of synchronisation that differed by 10%, with a misclassification rate of 8%. The performance
of a spectral-based classification (error rate approximately 33%) and of the classification with Daubechies wavelet (21%)
was significantly poorer than with the proposed wavelet optimisation. The method can be used for a number of different application
fields of surface EMG classification, as the feature space is adapted to the characteristics of the signal that discriminate
between classes.
An erratum to this article is available at . 相似文献