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131.
M T Maya A R Farinha A M Lucas J A Morais 《Journal of pharmaceutical and biomedical analysis》1992,10(10-12):1001-1006
An isocratic high-performance liquid chromatographic method is described for the quantitative analysis of phenytoin (PHT) in plasma and both phenytoin and its main metabolite, 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) in urine. Following ethyl acetate (plasma) and Extrelut-1 (urine) extraction, samples are analysed by means of a reversed-phase column (Nova-Pak C18), using a mobile phase consisting of methanol-water-tetrahydrofuran (40:60:4, v/v/v) with UV detection at 230 nm. The chromatography is complete in 10 min and the results show good precision (RSD 1.23-4.49%) and sensitivity for a linear range of 0.4-4.0 micrograms ml-1 for PHT in plasma, 0.1-1.0 microgram ml-1 for PHT in urine and 0.1-1.2 microgram ml-1 for p-HPPH in urine. The results indicate the method to be suitable for pharmacokinetic studies. 相似文献
132.
Summary Avoidance conditioning of inbred strains of mice was used to analyse the effects exerted by genetic factors on the action of nicotine. The experiments were carried out through an automatic programming and recording shuttle box device. The results indicate that the effects of nicotine are strain dependent. A facilitating effect on avoidance conditioning was observed in 6 of the 9 inbred strains, the strains characterized by a low performance showing generally the highest degree of facilitation. In two strains with a very high level of performance there was an impairing effect of nicotine on avoidance performance. 相似文献
133.
Conforti F Loizzo MR Statti GA Menichini F 《Biological & pharmaceutical bulletin》2005,28(9):1791-1794
The yield of methanolic extract and total phenol and non polar content of flowered parts from Achillea ligustica ALL. are reported. GC-MS analysis of the non polar fraction showed that the triterpene moretenol was the major constituent (17.228%) followed by stigmast-6-en-3beta-ol, veridiflorol and beta-amyrin (7.524%, 5.078% 4.470%, respectively). The antioxidant activities of the methanolic extract and its fractions from A. ligustica were carried out using two different in vitro assays, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and lipid peroxidation of liposomes assay. Methanolic extract showed higher radical scavenging activity on DPPH (IC50 of 50 microg/ml). This activity is probably due to the phenolic fraction which shown an IC50 value of 22 microg/ml. A different result was obtained from the methanolic extract on the lipid peroxidation of liposomes (IC50 of 416 microg/ml). The alpha-amylase inhibition assay was applied to evaluate antidiabetic activity. The methanolic extract showed weak activity (28.18% at 1 mg/ml) while the n-hexane fraction showed 74.96% inhibition at 250 microg/ml. 相似文献
134.
Emilio Franzoni Valentina Gentile Maria Chiara Colonnelli Daniela Brunetto Ilaria Cecconi Luisa Iero Filomena C Moscano Duccio M Cordelli Valentina Marchiani 《Italian journal of pediatrics》2010,36(1):30
Background
In 1997 Vagus Nerve Stimulation (VNS) received approval from the US Food and Drug Administration (FDA) as an adjunctive therapy in the treatment of medically intractable partial epilepsy in people aged 12 years and older who are ineligible for resective epilepsy surgery. Although the exact mechanisms of action are unknown, the use of VNS with children has increased, including those younger than 12 years of age, or those with generalized epilepsy.Methods
We describe the outcome for the first group of nine patients, aged 8-28 years, who had pharmaco-resistant epilepsy and were treated with VNS. During the follow up, we gradually and slowly increased the parameters of the stimulation in order to assess the efficacy of VNS even at parameters which would usually be considered "non-therapeutic", along with possible side effects and changes in quality of life.Results
At the last follow, up 1 patient was "seizures free", 3 were "very good responders", 3 were "good responders" and 2 were "non responders". We obtained an initial seizure reduction with low stimulation parameters, the highest current reached being 2.00 mA. This observation supports the possibility that, for younger patients, lower stimulation intensities than those commonly used in clinical practice for adults can be therapeutic. We also wanted to underline the reduction in seizure frequency (~91,7%) and the reduction in seizure duration (> 50%) in the patients affected by drug-resistant absence epilepsy. Adverse effects were mild, tolerable and, in most of cases, easily resolved by adjusting the stimulation parameters. Hoarseness of voice was the most frequent side effect. The improvements in the quality of life are relevant and seem to be independent of the VNS effect in controlling seizures.Conclusions
Our small experience seems to confirm the efficacy and safety of VNS in drug resistant partial and generalized epilepsy in developing age groups.135.
136.
Cetani F Pardi E Ambrogini E Lemmi M Borsari S Cianferotti L Vignali E Viacava P Berti P Mariotti S Pinchera A Marcocci C 《Clinical endocrinology》2006,64(2):146-152
OBJECTIVE: Familial isolated primary hyperparathyroidism (FIPH) can result from either incomplete expression of a syndromic form of familial primary hyperparathyroidism [multiple endocrine neoplasia type 1 (MEN 1), hyperparathyroidism-jaw tumour syndrome (HPT-JT) or familial hypocalciuric hypercalcaemia (FHH)] or still unrecognized causes. Design Genetic analyses of MEN1, HRPT2 and CASR genes in FIHP. PATIENTS: Seven well-characterized Italian kindreds with FIHP, with negative clinical features for MEN 1, HPT-JT and FHH. The mean age (+/- SD) at diagnosis was 45 +/- 17 years (range 18-70 years) in the probands and 42 +/- 18 years (range 15-69 years) in the other affected subjects. MEASUREMENTS: Direct sequencing of germline DNA of the MEN1, HRPT2 and CASR genes from probands. The region of interest was amplified in some family members. RESULTS: Germline MEN1 mutations were detected in three kindreds. Multiglandular involvement was found in all but one affected subject belonging to the three kindreds with MEN1 mutations. In these patients persistence/relapse of the disease was observed unless an extensive parathyroidectomy (excision of 3(1)/(2) glands) had been performed, with the exception of one patient, who is currently normocalcaemic 168 months after excision of two glands. No mutations of MEN1, HRPT2 and CASR genes were identified in the remaining four families. CONCLUSIONS: MEN1 genotyping appears worthwhile in FIHP families, as the finding of mutation(s) may predict multiglandular involvement and therefore have practical surgical implications, and prompt further investigation in the family, with the possibility of identifying new cases and beginning a programme of periodic surveillance for emergence of tumours in all carriers. 相似文献
137.
Tanamati C Suguimoto RL Atik E Copolla SG Galles FR Aiello VD Barbero-Marcial ML 《Arquivos brasileiros de cardiologia》2006,87(3):e1-e3
Atrioventricular septal defects account for 4% of congenital cardiac malformations and over 50% of cardiac defects seen in Down syndrome. Clinical presentation is marked by congestive heart failure early in infancy. Cyanosis is rarely found in infants and suggests irreversible pulmonary hypertension or associated cardiac defects as tetralogy of Fallot, double outlet right ventricle, Ebstein anomaly, persistent left superior vena cava draining in the left atrium (Barbero Marcial, personal communication). Children with Down's syndrome is particularly difficult to assess because they often suffer from upper airways obstruction, which may contribute to the increased pulmonary vascular resistance determined at cardiac catheterization. This association of factors becomes a challenge for operability and, we will report one such case. 相似文献
138.
Chen SC Cummings OW Hartley MP Filomena CA Cho WK 《Digestive diseases and sciences》2006,51(5):952-955
Hepatocellular carcinoma is known to be associated with underlying liver diseases, such as cirrhosis, hemochromatosis, and chronic viral hepatitis. All reported cases of hepatocellular carcinoma in association with Crohn’s disease involve patients treated previously with azathioprine or both azathioprine and steroids. However, hepatocellular carcinoma associated with the use of azathioprine and infliximab has not been reported. In this report, we describe an unusual case of hepatocellular carcinoma and focal hepatic glycogenosis (FHG) occurring in a non-cirrhotic Crohn’s disease patient who has been treated with both azathioprine and infliximab. 相似文献
139.
140.
D'Amato F Cocco C Noli B Cabras T Messana I Ferri GL 《Journal of chemical neuroanatomy》2012,44(2):57-65
VGF or VGF nerve growth factor inducible is a protein that has been found to play a role in regulating energy homeostasis and metabolism. From VGF precursor derive two neuroendocrine regulatory peptides NERP-1 and NERP-2 that, intracerebroventricular (icv) injected, modulate the antidiuretic hormone (ADH) release. Thus, we investigated possible modulations of the NERPs and other VGF peptides (namely VGF C-terminus, TLQP and PGH) in the hypothalamic-pituitary-axis, adrenal gland and plasma upon osmotic stimuli. The latter tissues were studied using water deprived (WD), salt loaded (SL), rehydrated after salt cargo and control rats by immunohistochemistry and immunoenzymatic assays. The high-performance liquid chromatography ensured the endogenous presence of the two NERPs in both plasma and hypothalamus. Upon dehydration, NERP-1 levels increased in the median eminence (M.E.) only, while using SL rats, the values of both NERPs increased in the M.E. and even in the hypothalamus. Conversely, in the blood of WD and SL rats, the levels of NERP-1 and NERP-2 decreased while, using pituitary from both rat groups, levels of NERP-2 increased and those of NERP-1 decreased. Reduction in the VGF C-terminus peptide levels was observed exclusively in the M.E. (using WD rats) and pituitary (using WD and SL rats), while PGH and TLQP peptide levels never changed in all tissues tested. By immunohistochemistry, the VGF peptides studied (apart from the TLQP peptides) were present in the hypothalamic and pituitary ADH containing neurons of the control rats, while using WD and SL rats, an immunostaining increase was selectively revealed for VGF C-terminus peptides in the hypothalamic neurons that produce ADH. All VGF changes found using SL rats disappeared after only 1h of rehydration. In conclusion, we hypothesize that NERPs may be involved in both autocrine and endocrine mechanisms important for the fluid balance. 相似文献