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排序方式: 共有1933条查询结果,搜索用时 15 毫秒
41.
Napoli C Ackah E De Nigris F Del Soldato P D'Armiento FP Crimi E Condorelli M Sessa WC 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(19):12467-12470
The effects of chronic treatment with nitric oxide-containing aspirin (NO-aspirin, NCX-4016) in comparison with regular aspirin or placebo on the development of a chronic disease such as atherosclerosis were investigated in hypercholesterolemic low-density lipoprotein (LDL)-receptor-deficient mice. Male mice were assigned randomly to receive in a volume of 10 ml/kg either placebo (n = 10), 30 mg/kg/day NO-aspirin (n = 10), or 18 mg/kg/day of regular aspirin (n = 10). After 12 weeks of treatment, the computer-assisted imaging analysis revealed that NO-aspirin reduced the aortic cumulative lesion area by 39.8 +/- 12.3% compared with that of the placebo (P < 0.001). Regular aspirin did not reduce significantly aortic lesions (-5.1 +/- 2.3%) compared with the placebo [P = 0.867, not significant (NS)]. Furthermore, NO-aspirin reduced significantly plasma LDL oxidation compared with aspirin and placebo, as shown by the significant reduction of malondialdehyde content (P < 0.001) as well as by the prolongation of lag-time (P < 0.01). Similarly, systemic oxidative stress, measured by plasma isoprostanes, was significantly reduced by treatment with NCX-4016 (P < 0.05). More importantly, mice treated with NO-aspirin revealed by immunohistochemical analysis of aortic serial sections a significant decrease in the intimal presence of oxidation-specific epitopes of oxLDL (E06 monoclonal antibody, P < 0.01), and macrophages-derived foam cells (F4/80 monoclonal antibody, P < 0.05), compared with placebo or aspirin. These data indicate that enhanced NO release by chronic treatment with the NO-containing aspirin has antiatherosclerotic and antioxidant effects in the arterial wall of hypercholesterolemic mice. 相似文献
42.
Sebastiano Bruno Solerte Marisa Fioravanti Nicola Schifino Anna Linda Patti Gabriella Gamba Ettore Ferrari 《Acta diabetologica》1988,25(3):235-242
Summary Diabetic microangiopathy may be associated with the pathogenesis and progression of autonomic and peripheral neuropathy. In
17 long-standing type I diabetic patients with peripheral and autonomic cardiovascular neuropathy, several hemorheological
and hemostatic alterations were found compared to 13 matched type I patients without neuropathy. In particular, increased
plasma von Willebrand factor antigen (p<0.001), fibronectin (p<0.001) and fibrinogen (p<0.001) levels were demonstrated in
neuropathic in comparison with non-neuropathic diabetic patients. Moreover negative correlations between these parameters
and both motor and sensitive conduction velocity of median, sural and peroneal nerves were observed in diabetic patients with
neuropathy. Higher blood viscosity (p<0.05 at shear-rate of 450 and 225 s−1; p<0.01 at 90 s−1; p<0.001 at 4.5 and 2.25 s−1), plasma viscosity (p<0.001) and lower erythrocyte filtrability (p<0.001) were also found in neuropathic compared to non-neuropathic
diabetics. Increased prevalence of retinopathy (p<0.01) and nephropathy (p<0.001) was finally reported in patients with autonomic
and peripheral neuropathy. Microvascular disease may be involved in the development of neuropathy in long-term type I diabetes
mellitus.
This study was presented in part at the 23rd Annual Meeting of the European Association for the Study of Diabetes, Leipzig
(GDR), 15–19 September 1987. 相似文献
43.
44.
Placental expression of soluble fms-like tyrosine kinase 1 is increased in singletons and twin pregnancies with intrauterine growth restriction 总被引:1,自引:0,他引:1
Nevo O Many A Xu J Kingdom J Piccoli E Zamudio S Post M Bocking A Todros T Caniggia I 《The Journal of clinical endocrinology and metabolism》2008,93(1):285-292
OBJECTIVE: Intrauterine growth restriction (IUGR) is characterized by decreased placental perfusion. Low oxygen has been shown to increase soluble fms-like tyrosine kinase 1 (sFlt-1) expression in the human placenta. The objective of this study was to examine sFlt-1 expression in different types of IUGR pregnancies, including early-onset severe cases characterized by abnormal umbilical and uterine artery Doppler and discordant IUGR twins in which the normal cotwin represents the optimal control because both placentas share the same uterine environment. PATIENTS: Placentas from four subgroups were collected: early severe IUGR with umbilical artery absent end diastolic flow (n = 19), small for gestational age with normal uterine and umbilical artery Doppler (n = 11), severely growth-restricted dichorionic and monochorionic twins with abnormal umbilical artery Doppler (n = 9), preeclamptic twins (n = 3), and age-matched normal singletons (n = 19) and twin controls (n = 8). RESULTS: Expression of sFlt-1 mRNA and protein was significantly increased in IUGR placentas compared with small for gestational age and normal control placentas. sFlt-1 expression levels were also significantly greater in the small IUGR twin placentas from discordant twin pregnancies compared with the normal cotwin. In preeclamptic twins, sFlt-1 expression was increased in only one of the two placentas. CONCLUSIONS: Our results demonstrate that sFlt-1 expression is increased in severe IUGR placentas with abnormal umbilical artery Doppler of singletons and also in discordant IUGR twins. Reduced placental perfusion may contribute to the increased expression of sFlt-1 in IUGR pregnancies. Our data are compatible with differential sFlt-1 expression in placentas from discordant twins. 相似文献
45.
Mario Santagata Umberto Tozzi Ettore Lamart Gianpaolo Tartaro 《Journal of maxillofacial and oral surgery》2015,14(3):682-686
Introduction
Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient’s life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions.Materials and methods
This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery.Conclusion
The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only. 相似文献46.
Concolino P Mello E Patrosso MC Penco S Zuppi C Capoluongo E 《Metabolism: clinical and experimental》2012,61(4):519-524
More than 90% of all cases of congenital adrenal hyperplasia (CAH) result from steroid 21-hydroxylase gene (CYP21A2) mutations. The CYP21A2 gene is located in the human leukocyte antigen (HLA) class III region on the short arm of chromosome 6p21.3, along with an inactive pseudogene, CYP21A1P, that is 98% homologous in its coding sequence with CYP21A2. Most CYP21A2 mutations result from intergenic recombinations between CYP21A2 and the closely linked CYP21A1P pseudogene. Rare mutations not generated by gene conversion account for only 5% to 10% of 21-hydroxylase deficiency alleles. However, detection of these rare and spontaneous mutations has continued to expand worldwide. We identified 2 novel CYP21A2 missense mutations (p.H282N and p.Y191H) in 2 Italian patients with simple-virilizing and nonclassic CAH forms. Functional analysis of these CYP21A2 mutations was performed. Functional in vitro assay for mutagenized CYP21A2 enzymes was performed in transiently transfected mammalian cells to test the residual enzyme activity and the apparent kinetic values. The residual activities obtained allowed us to classify the p.H282N and p.Y191H variants as simple-virilizing and nonclassic CAH associated mutations, respectively. These results correlate with the rate of severity of the patients' disease. This finding provides a further contribution for assisting in the diagnosis of CAH patients. 相似文献
47.
One-hundred patients were included to evaluate the role of cerebral computed tomography (CT) to improve patient selection in asymptomatic internal carotid stenosis. Symptomatic patients were assigned to group A, asymptomatic patients to group B. A cerebral CT pattern A was observed in groups A and B in 60% and 20%, respectively (P < .0001). Between A and B groups, type 6 plaques were found, respectively, in 26.7% and 7.5% of patients (P = .01); a type 5 in 51.7% and 45% (P = .32) of patients; and a type 4 in 21.7% and 47.5% of patients, respectively (P = .006). Within B group, the association of CT pattern A and histological plaque level 4, 5, and 6 was, respectively, 25% (P = .15), 50% (P = .53), and 25% (P = .16). In group B, a 7-fold risk increase in CT pattern A was found in patients with level 6 plaque. In asymptomatic patients with high-risk plaque, a basal cerebral CT scan can be used as diagnostic tool to improve patient selection for intervention. 相似文献
48.
49.
Ettore Salsano Laura Farina Costanza Lamperti Giuseppe Piscosquito Franco Salerno Lucia Morandi Franco Carrara Eleonora Lamantea Massimo Zeviani Graziella Uziel Mario Savoiardo Davide Pareyson 《Journal of neurology》2013,260(6):1617-1623
Respiratory chain disorders (RCDs) have been included in the differential diagnosis of adult-onset leukodystrophies. Here, we first report a 32-year-old female with an atypical, adult-onset, non-syndromic RCD due to a mitochondrial DNA deletion and manifesting as complicated ataxia. A ‘leukodystrophic’ pattern was found on brain MRI, but it was neither isolated nor predominant because of the presence of overt basal ganglia and infratentorial lesions, which led us to the proper diagnosis. Subsequently, we evaluated our series of patients with RCDs in order to verify whether a ‘leukodystrophic’ pattern with little or no involvement of deep grey structures and brainstem may be found in adult-onset RCDs, as reported in children. Among 52 patients with adult-onset RCDs, no case with a ‘leukodystrophic’ pattern was found, apart from three cases with a classical phenotype of mitochondrial neurogastrointestinal encephalopathy. In addition, no case of RCDs was found among six cases of adult-onset leukodystrophy of unknown origin and at least one feature suggestive of mitochondrial disease. The review of the literature was in agreement with these findings. Thus, we provide evidence that, unlike in children, RCDs should not be included in the differential diagnosis of adult-onset leukodystrophies, except when there are additional MRI findings or clinical features which unequivocally point towards a mitochondrial disorder. 相似文献
50.
De Michele Giovanna Galatolo Daniele Galosi Serena Mignarri Andrea Silvestri Gabriella Casali Carlo Leuzzi Vincenzo Ricca Ivana Barghigiani Melissa Tessa Alessandra Cioffi Ettore Caputi Caterina Riso Vittorio Dotti Maria Teresa Saccà Francesco De Michele Giuseppe Cocozza Sirio Filla Alessandro Santorelli Filippo M. 《Journal of neurology》2022,269(3):1476-1484
Journal of Neurology - Spinocerebellar ataxia type 14 (SCA14) is a dominantly inherited neurological disorder characterized by slowly progressive cerebellar ataxia. SCA14 is caused by mutations in... 相似文献