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排序方式: 共有8157条查询结果,搜索用时 22 毫秒
991.
Paola Sarchielli Luigi Alberto Pini Francesca Coppola Cristiana Rossi Antonio Baldi Maria Luisa Mancini Paolo Calabresi 《Neuropsychopharmacology》2007,32(6):1384-1390
Based on experimental evidence of the antinociceptive action of endocannabinoids and their role in the modulation of trigeminovascular system activation, we hypothesized that the endocannabinoid system may be dysfunctional in chronic migraine (CM). We examined whether the concentrations of N-arachidonoylethanolamide (anandamide, AEA), palmitoylethanolamide (PEA), and 2-arachidonoylglycerol (2-AG) in the CSF of patients with CM and with probable CM and probable analgesic-overuse headache (PCM+PAOH) are altered compared with control subjects. The above endocannabinoids were measured by high-performance liquid chromatography (HPLC), and quantified by isotope dilution gas-chromatography/mass-spectrometry. Calcitonin gene-related peptide (CGRP) levels were also determined by RIA method and the end products of nitric oxide (NO), the nitrites, by HPLC. CSF concentrations of AEA were significantly lower and those of PEA slightly but significantly higher both in patients with CM and PCM+PAOH than in nonmigraineur controls (p<0.01 and p<0.02, respectively). A negative correlation was found between AEA and CGRP levels in CM and PCM+PAOH patients (r=0.59, p<0.01 and r=-0.65, p<0.007; respectively). A similar trend was observed between this endocannabinoid and nitrite levels. Reduced levels of AEA in the CSF of CM and PCM+PAOH patients may reflect an impairment of the endocannabinoid system in these patients, which may contribute to chronic head pain and seem to be related to increased CGRP and NO production. These findings support the potential role of the cannabinoid (CB)1 receptor as a possible therapeutic target in CM. 相似文献
992.
Luisa Businco Paola Falconieri Barbara Bellioni-Businco Sami L. Bahna 《Pediatric allergy and immunology》2002,13(1):68-71
Food-induced vasculitis seems to be rare and is considered by some as controversial. The reported cases in the literature are few and mostly on adult patients. Described in this report are two children with severe vasculitis caused by specific foods. They were diagnosed at two separate allergy centers that have a special interest in food allergies. Case 1 was an 8-year-old girl with a 9-month history of cutaneous vasculitis with large joints involvement. Case 2 was a 23-month-old girl with an 8-month history of multiple hospitalizations for recurrent acute severe cutaneous and mucous membrane vasculitis with large joints involvement. In both patients, skin biopsy showed leucocytoclastic vasculitis. In neither of the patients could the symptoms be attributed to drug intake, infection, autoimmunity, or other systemic disease. Case 1 had a moderately elevated serum total immunoglobulin E (IgE) level and strongly positive skin test and radioallergosorbent test (RAST) to cow's milk and hen's egg, both of which were proven to be the cause by elimination-challenge tests. Case 2 had a slightly elevated serum total IgE level, but negative skin tests to foods, including chocolate that was suspected by the mother. Avoidance of chocolate resulted in remission, except following accidental ingestion of cocoa-containing products. These findings support the few previous reports on food-induced vasculitis, an entity that seems rare but may be more common than currently realized. 相似文献
993.
Luisa Benvegnu Attilio Cecchetto Franco Noventa Federico Tremolada Arturo Ruol Alfredo Alberti 《Liver international》1992,12(2):80-83
Abstract: Fifty-four patients with cirrhosis, found to have a space-occupying lesion in the liver by ultrasound (US), underwent US-assisted biopsy of the lesion and were then followed prospectively to define outcome and survival. Histologic examination revealed hepatocellular carcinoma in 26 patients, while five had liver cell dysplasia without hepatocellular carcinoma and 23 had no evidence of tumor or of dysplasia. All five patients with an initial diagnosis of dysplasia developed hepatocellular carcinoma during follow-up and their survival curve was similar to that of patients with liver cancer and significantly worse than that of patients without dysplasia or tumor. There were five false-negative cases of hepatocellular carcinoma among the patients with negative histology. Overall, US-assisted liver biopsy diagnosed malignancy with a sensitivity of 72%, which increased to 86% when dysplasia was considered a pre-neoplastic lesion. 相似文献
994.
Paolo Coruzzi Almerina Biggi Luisa Musiari Carlo Ravanetti Almerico Novarini 《Pflügers Archiv : European journal of physiology》1986,407(6):638-642
The renal vascular and functional responses to acute central hypervolemia by water immersion to the neck were determined in six normal subjects. During isotonic-isooncotic expansion by water immersion there was a significant increase in urine flow from 1.1±0.1 to 6.9±1.0 ml/min (p<0.05) and sodium excretion from 99.1±8.8 to 300±28 Eq/min (p<0.05). Glomerular filtration rate did not change while renal blood flow significantly increased during water immersion. Deep intrarenal venous pressure (IRVP) increased from 18.2±1.4 to 32±1.7 mmHg (p<0.05) while mean arterial pressure was unchanged. This marked natriuresis seen during water immersion was associated with reduced renal vascular resistance and increased deep intrarenal venous pressure demonstrating that continued natriuresis could relate to increased capillary hydrostatic pressure. 相似文献
995.
996.
Tagliabue E Agresti R Casalini P Mariani L Carcangiu ML Balsari A Veronesi U Ménard S 《European journal of cancer (Oxford, England : 1990)》2006,42(8):1057-1061
The early peak of relapse in patients with breast carcinomas that overexpress HER2 oncoprotein and dissemination to the axillary lymph nodes might be related to proliferation of micrometastatic lesions induced by EGF family growth factors released at the time of surgery. If the levels of these growth factors have an impact on relapse, the survival of patients with positive nodes and HER2-positive tumours should be dependent on surgery wideness. To test this hypothesis, HER2 status of primary tumours from patients included in a randomized clinical trial addressing conservative quadrantectomy versus radical mastectomy was retrospectively analyzed. In HER2-negative patients, independently of node infiltration, and in HER2-positive patients without node infiltration, no differences in survival according to the type of surgery were observed. In patients with positive nodes and HER2-positive tumours the estimation of the time-dependent log-hazard ratios showed that radical mastectomy significantly increased early death rates (P=0.037). 相似文献
997.
Balestrieri C Felice F Piacente S Pizza C Montoro P Oleszek W Visciano V Balestrieri ML 《Biochemical pharmacology》2006,71(10):1479-1487
Yuccaols (A, B, C) are phenolic constituents isolated from Yucca schidigera bark characterized by unusual spirostructures made up of a C15 unit and a stilbenic portion closely related to resveratrol. These novel compounds are of particular interest for their antioxidant and anti-inflammatory properties. However, their effects on cell proliferation, migration, and platelet-activating factor (PAF) biosynthesis remain unknown. PAF, a potent mediator of inflammation, is known to promote angiogenesis and in vitro migration of endothelial cells and Kaposi's sarcoma (KS) cells. The objective of our study was to determine the effect of Yuccaols and resveratrol on the vascular endothelial growth factor (VEGF)-induced proliferation, migration, and PAF biosynthesis in KS cells. The results indicated that Yuccaols (25 microM) were more effective than resveratrol (25 microM) in inhibiting the VEGF-induced KS cell proliferation. Western blot analysis revealed that Yuccaols reduced the VEGF-induced phosphorylation of p38 and p42/44, thus indicating a possible interference with the mechanism underlying the VEGF-stimulated cell proliferation. Furthermore, Yuccaols completely inhibited the VEGF-stimulated PAF biosynthesis catalyzed by the acetyl-CoA:lyso-PAF acetyltransferase and enhanced its degradation through the PAF-dependent CoA-independent transacetylase (250% of control). In addition, Yuccaol C abrogated the PAF-induced cell motility whereas Yuccaol A and Yuccaol B reduced the cell migration from 7.6 microm/h to 6.1 microm/h and 5.6 microm/h, respectively. These results indicate that the anti-inflammatory properties attributed to Yucca schidigera can be ascribed to both resveratrol and Yuccaols and provide the first evidences of the anti-tumor and anti-invasive properties of these novel phenolic compounds. 相似文献
998.
Phosphodiesterase PDE3 blunts the positive inotropic and cyclic AMP enhancing effects of CGP12177 but not of noradrenaline in rat ventricle
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1.--The cardiostimulant effects of CGP12177, mediated through a beta(1)-adrenoceptor site with low affinity for (-)-propranolol, are potentiated by the nonselective PDE inhibitor IBMX but the role of PDE isoenzymes is unknown. We studied the effects of the PDE3-selective inhibitor cilostamide (300 nM) and PDE4-selective inhibitor rolipram (1 microM) on the positive inotropic and cyclic AMP-enhancing effects of CGP12177 and noradrenaline in right ventricular strips of rat. 2.--CGP12177 (under (-)-propranolol 200 nM) only increased contractile force in the presence of either cilostamide or rolipram with -logEC(50)M 6.7 (E(max)=23% over basal) and 7.1 (E(max)=50%) respectively. The combination of cilostamide and rolipram caused CGP12177 to enhance contractile force with -logEC(50)M=7.7 and E(max)=178%. 3.--The positive inotropic effects of noradrenaline (-logEC(50)M=6.9) were potentiated by rolipram (-logEC(50)M=7.4) but not by cilostamide (-logEC(50)M=7.0). 4.--In the presence of rolipram and (-)-propranolol, noradrenaline (2 microM) and CGP12177 (10 microM) produced matching inotropic effects but failed to increase cyclic AMP levels. 20 microM (-)-noradrenaline increased cyclic AMP levels, a response further enhanced by rolipram. 5.--Both PDE3 and PDE4 of rat ventricle appear to hydrolyse cyclic AMP generated through the low-affinity beta(1)-adrenoceptor site, thereby preventing inotropic responses of CGP12177. When (-)-noradrenaline interacts with the beta(1)-adrenoceptor, the generated cyclic AMP is hydrolysed only by PDE4, thereby reducing cardiostimulation. 相似文献
999.
Maestrelli F González-Rodríguez ML Rabasco AM Mura P 《International journal of pharmaceutics》2006,312(1-2):53-60
The combined approach of cyclodextrin complexation and entrapment in liposomes was investigated in order to develop an effective topical formulation of ketoprofen. Equimolar complex of drug and hydroxypropyl-beta-cyclodextrin (HPbetaCyd) was added at different concentrations to the aqueous phase of liposomes consisting of phosphatidylcholine and cholesterol (60%/40%, w/w). Liposomes were prepared with different techniques, such as thin layer evaporation, freezing and thawing, extrusion through microporous membrane, and reverse phase evaporation method, obtaining, respectively, multi-lamellar vesicles (MLV), frozen and thawed MLV (FATMLV), small uni-lamellar vesicles (SUV) and large uni-lamellar vesicles (LUV). Size and morphology of the different types of liposomes were investigated by light scattering analysis, transmission electron microscopy, and confocal laser scanning microscopy, whereas drug entrapment efficiency was determined by dialysis experiments. Cyclodextrin complexation improved drug solubilization and allowed a strong improvement of its entrapment into the aqueous liposomal phase. Liposome preparation method and operating conditions clearly affected both liposome size and drug loading capacity. Encapsulation efficiency increased with increasing the complex concentration up to 10 mM, and was in the order MLV>LUV>SUV. An opposite behaviour was observed for FATMLV, probably due to the freezing phase required by such a preparation method, which reduced the complex solubility. Moreover, it was not possible to use higher complex concentrations, due to the destabilizing effect of cyclodextrins toward the liposomal membrane. Permeability studies of drug-HPbetaCyd complexes, directly in solution or incorporated in liposomes, performed across artificial membranes simulating the skin behaviour, highlighted, as expected, a prolonged release effect of liposomal formulations. Furthermore, the drug permeation rate depended on the vesicle characteristics and varied in the order: SUV>MLV=FATMLV>LUV. Therefore, the most suitable liposome preparation method can be suitably selected on the basis of drug encapsulation efficiency and/or desired drug release rate. 相似文献
1000.
Fornasini M Brotons C Sellarès J Martinez M Galán ML Sáenz I da Pena JM 《Family practice》2006,23(1):28-33
BACKGROUND: There are two promising methods to assess cardiovascular risk: the Adult Treatment Panel III (ATPIII) and the Systematic Coronary Risk Evaluation (SCORE). The ATPIII calculates the 10-year risk of coronary events based on an adaptation of the original Framingham function. The SCORE chart is based on European studies and measures the absolute risk of cardiovascular mortality in the next 10 years. OBJECTIVE: To evaluate the clinical consequences of using different methods to calculate cardiovascular risk and different primary prevention guidelines. METHODS: A cross sectional study of 914 dyslipidemic patients from three primary health centres from Catalonia, Spain, was conducted. Outcome variables were the risk level according to the different equations (classical Framingham table by Anderson, ATPIII adapted Framingham table, and SCORE system), and candidates for lipid lowering treatment according to European and ATPIII guidelines. RESULTS: The proportion of high-risk patients according to the three equations and excluding diabetic patients was 13.5%, 11.4% and 7.1%, respectively, and 20.2%, 25.7% and 29.2%, respectively when including diabetic patients. The prevalence of candidates for lipid lowering treatment according to European guidelines and ATPIII guidelines were 28.8% and 39.3%, respectively. A 49% disagreement with a Kappa of -0.1, and a 37% disagreement with a Kappa of 0.08 were observed when comparing candidates identified for lipid lowering treatment and patients actually receiving that treatment, according to ATPIII and SCORE guidelines, respectively. CONCLUSION: Our results suggest important clinical and economic consequences when comparing European guidelines or ATPIII guidelines for the treatment of dyslipidemic patients in general practice. 相似文献