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21.
The effects of clozapine on dopamine neurons projecting to the medial-prefrontal cortex, nuclei accumbens and caudatus were compared. Clozapine (1.25 mg/kg i.v.) maximally stimulated the firing rate and burst activity of dopamine neurons projecting to the medialprefrontal cortex. Much higher doses (5 and 10 mg/kg i.v.) were needed to stimulate mesoaccumbens and nigrostriatal dopamine neurons. The results suggest that the activation of mesocortical dopamine neurons is responsible for clozapine-induced dopamine release in the prefrontal cortex. 相似文献
22.
Orlandi MC Melis GB Rossini D Macchia A Fioretti P 《Journal of chemotherapy (Florence, Italy)》1991,3(Z1):237-239
Problems concerning antimicrobial prophylaxis in obstetric surgery are reviewed from the first experiences with multiple-dose treatments to the new short-term prophylaxis. With the purpose to evaluate the effectiveness of a short-term scheme, a controlled population of 134 obstetric patients was treated with a double dose of 2 g i.m. of cefotetan. Clinically important infectious complications were not observed. 相似文献
23.
Changes in conjugated linoleic acid and its metabolites in patients with chronic renal failure 总被引:2,自引:0,他引:2
Lucchi L Banni S Melis MP Angioni E Carta G Casu V Rapanà R Ciuffreda A Corongiu FP Albertazzi A 《Kidney international》2000,58(4):1695-1702
BACKGROUND: Conjugated linoleic acid (CLA) is a mixture of isomers of linoleic acid with conjugated double bonds that constitutes the most abundant fatty acid with conjugated dienes (CDs) in humans. CLA, erroneously considered in the past as a product of lipoperoxidation, has a dietary origin and has shown to possess anticarcinogenic and anti-atherogenic activity, mainly in animal studies. CLA can be metabolized to conjugated linolenic acid (CD18:3) and to conjugated eicosatrienoic acid (CD20:3) and these metabolites may be implicated in CLA activity. Because of the presence of dyslipidemia and the high incidence of cardiovascular and neoplastic diseases in uremic patients, we evaluated CLA and its metabolites in these patients in order to evaluate their metabolism and site distribution. METHODS: We measured CLA, CD18:3, CD20:3, CD fatty acid hydroperoxides (lipoperoxidation products), and linoleic acid in the plasma, adipose tissue, and red blood cell (RBC) membranes by using high-pressure liquid chromatography in the following groups: (1) 23 chronic renal failure (CRF) patients with creatine clearance (CCr)> 10 mL/min (26.2 +/- 16.7); (2) 21 end-stage CRF patients in conservative treatment with CCr <10 mL/min (6.8 +/- 1.8); (3) 30 hemodialysis (HD) patients; and (4) 30 healthy controls. RESULTS: The incorporation of CLA, CD18:3, and CD20:3 in RBC membranes was significantly reduced in group 1 and was even more reduced in groups 2 and 3. CLA significantly increased both in the plasma and adipose tissue of end-stage CRF patients only. CD18:3 and CD20:3 did not change in the plasma and adipose tissue of any group. No significant changes in linoleic acid and CD fatty acid hydroperoxides were found. CONCLUSIONS: The alterations of CD in CRF patients are not due to lipoperoxidation. The increased levels of CLA in plasma and adipose tissue of end-stage CRF patients may be due either to a reduced metabolization of CLA to CD18:3 and CD20:3, or to an altered site distribution with reduced incorporation in cellular membranes and accumulation in the plasma and adipose tissue. The clinical significance of these changes remains to be investigated. 相似文献
24.
Antonio Macciò M.D. Paola Lai M.D. Maria Cristina Santona M.D. Loredana Pagliara M.D. Gian Benedetto Melis M.D. Giovanni Mantovani M.D. 《Gynecologic oncology》1998,69(3):248-252
The serum levels of interleukin-(IL-)1α, IL-1β, IL-2, IL-6, TNFα, and sIL-2R and the proliferative response of peripheral blood mononuclear cells (PBMC) to phytohemagglutinin (PHA), anti-CD3 monoclonal antibody (mAb), recombinant IL-2 (rIL-2), and the combination of PHA or anti-CD3 mAb with rIL-2 were studied and correlated with serum levels of C-reactive protein (CRP) in women with advanced epithelial ovarian cancer. The expression of CD25 and CD122 subunities of membrane-bound IL-2R on PHA- or anti-CD3 mAb-stimulated PBMC was also studied. In comparisons with the controls, PBMC response to PHA, anti-CD3 mAb, and rIL-2 was significantly lower in the cancer patients. The addition of exogenous rIL-2 to the PBMC cultures increased response in both controls and patients but did not modify the significance of the differences. After stimulation with PHA or anti-CD3 mAb, the percentage of PBMC CD25+or CD122+was significantly lower in patients. The serum levels of IL-1α, IL-1β, IL-6, TNFα, sIL-2R, and CRP were significantly increased in patients compared to the controls. Instead, no differences were observed for serum levels of IL-2. A strong association was found between high serum levels of the above-mentioned cytokines, sIL-2R, and CRP. The results of our study on advanced stage (IIIb–IV) ovarian cancer patients are consistent with the previously reported hypothesis that high IL-6 and/or CRP serum levels may represent an important and independent prognostic factor of the likely outcome in cancer patients. 相似文献
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26.
Validation of a Frailty Index from The Older Persons and Informal Caregivers Survey Minimum Data Set
Jennifer E. Lutomski MS Maria A.E. Baars PhD Janneke A. van Kempen MD Bianca M. Buurman PhD Wendy P.J. den Elzen PhD Aaltje P.D. Jansen PhD Gertrudis I.J.M. Kempen PhD Paul F.M. Krabbe PhD Bas Steunenberg PhD Ewout W. Steyerberg PhD Marcel G.M. Olde‐Rikkert PhD René J.F. Melis PhD 《Journal of the American Geriatrics Society》2013,61(9):1625-1627
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Cancer is a major worldwide health problem and one of the leading causes of death either in developed or developing countries. Plant extracts and derivatives have always been used for various disease treatments and many anticancer agents issued from plants and vegetables are clinically recognized and used all over the world. Lycium europaeum (Solanaceae) also called “wolfberry” was known since ancient times in the Mediterranean area as a medicinal plant and used in several traditional remedies. The Lycium species capacity of reducing the incidence of cancer and also of halting or reserving the growth of cancer was reported by traditional healers. In this study, the antiproliferative capacity, protective properties, and antioxidant activity of the hydro-alcoholic fruit extract of Lycium europaeum were investigated. Results showed that Lycium extract exhibits the ability to reduce cancer cell viability, inhibits proliferation, and induces apoptosis in A549 human lung cancer cells and PC12 rat adrenal medulla cancer cells, in a concentration- and time-dependent manner. Cytotoxic effect on normal rat cerebellum granule cells was assessed to be nonsignificant. Results also showed that Lycium fruit extract protected lipids, proteins, and DNA against oxidative stress damages induced by H2O2 via scavenging reactive oxygen species. 相似文献
29.
Composite binary endpoints are increasingly used as primary endpoints in clinical trials. When designing a trial, it is crucial to determine the appropriate sample size for testing the statistical differences between treatment groups for the primary endpoint. As shown in this work, when using a composite binary endpoint to size a trial, one needs to specify the event rates and the effect sizes of the composite components as well as the correlation between them. In practice, the marginal parameters of the components can be obtained from previous studies or pilot trials; however, the correlation is often not previously reported and thus usually unknown. We first show that the sample size for composite binary endpoints is strongly dependent on the correlation and, second, that slight deviations in the prior information on the marginal parameters may result in underpowered trials for achieving the study objectives at a pre-specified significance level. We propose a general strategy for calculating the required sample size when the correlation is not specified and accounting for uncertainty in the marginal parameter values. We present the web platform CompARE to characterize composite endpoints and to calculate the sample size just as we propose in this paper. We evaluate the performance of the proposal with a simulation study and illustrate it by means of a real case study using CompARE. 相似文献
30.
Occlusal dysesthesia (OD) is a disorder characterised by the sensation of uncomfortable bite with no obvious occlusal discrepancy. It is usually associated with emotional distress and is elicited by dental occlusal procedures. Multiple dental treatments are often provided to try to resolve the symptoms, but the outcome is usually dissatisfying for the dentist and disappointing for the patient. To summarise the specific features of OD, a PubMed search was carried out looking for all papers related to the topic. The references from the studies selected and from review articles were also examined for further relevant papers. A total of 138 articles were first identified, of which 18 of them were considered relevant to the topic. This article reviews the epidemiology, taxonomy and etio‐pathophysiology, symptomatology, diagnosis and treatment of OD, with special relevance to issues of clinical importance and dental therapy. Any dental treatment must be avoided in patients with OD, because the results could be inadequate and it usually worsens the symptoms. 相似文献