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排序方式: 共有1497条查询结果,搜索用时 15 毫秒
991.
Marra MP Cacciavillani L Corbetti F Tarantini G Ramondo AB Napodano M Basso C Lacognata C Marzari A Maddalena F Iliceto S 《Echocardiography (Mount Kisco, N.Y.)》2010,27(9):1120-1129
Background: Percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) is sometimes complicated by microvascular damage and hemorrhage. Hemoglobin degradation products have magnetic susceptibility effects which help in detecting hemorrhagic AMI by T2‐weighted cardiac magnetic resonance (CMR) images. Objectives: To investigate the possibility to detect intramyocardial hemorrhage after AMI and to assess its contribution to the delayed hypoenhanced core on late gadolinium enhancement (LGE) CMR, a feature traditionally referred to as microvascular obstruction. Methods: Consecutive patients with AMI who underwent PCI and CMR were investigated. Hypointense zones T2‐weighted images were labelled as “hemorrhagic” AMI. Areas of late hypoenhancement on LGE CMR were considered as regions of persistent microvascular damage (PMD). Only transmural AMI were considered. Results: A total number of 108 transmural AMI patients were eventually enrolled and divided into two groups according to the presence of hypoenhancement on T2 images. Thirty‐two patients showed an hypointense stria within the high signal intensity zone on T2‐weighted images; all these patients showed midmural PMD on LGE. Among the remaining 76 patients, only 14 (18.4%) showed PMD in the subendocardial region. The angiographic outcome was worse in patients with hemorrhagic AMI, with a lower prevalence of TIMI 3 (65.6% vs. 96.1%, P = 0.017) and higher prevalence of myocardial blush grade 0 (84.4% vs. 13.2%, P < 0.001) post‐PCI. Conclusions: T2‐weighted CMR in reperfused AMI allows identification of hemorrhage, related to PMD areas on LGE images and to a worse reperfusion profile on angiography. These features open new avenues of investigation for prognostic assessment of reperfused AMI. (Echocardiography 2010;27:1120‐1129) 相似文献
992.
Filippo Pieralli Maddalena Grazzini Vieri Vannucchi Antonio Mancini Daniele Cammelli Carlo Nozzoli 《Clinical rheumatology》2014,33(3):429-433
Catastrophic antiphospholipid syndrome (CAPS) is a rare variant of antiphospholipid syndrome characterized by widespread thrombotic microangiopathy and multiorgan failure. Clinically, CAPS signs and symptoms can mimic vasculitis of systemic lupus erythematosus, disseminated intravascular coagulation, and thrombotic thrombocytopenic purpura. CAPS is burdened by high mortality, nearly 50 % in most series. However, patients surviving the acute phase rarely suffer of CAPS relapses. Moreover, concomitant pulmonary hemorrhagic alveolitis is a very rare complication warranting an ominous prognosis. Only few reports of relapsing CAPS are described in literature, and pathogenetic mechanisms are poorly understood and the optimal treatment is yet unknown. We report a case of a young man suffering from multiple relapses of CAPS and recurrent hemorrhagic pulmonary alveolitis refractory to aggressive combination treatment. 相似文献
993.
Piccirillo G Germanò G Vitarelli A Ragazzo M di Carlo S De Laurentis T Torrini A Matera S Magnanti M Marchitto N Bonanni L Magrì D 《International journal of cardiology》2006,110(2):160-166
BACKGROUND: Early hypertension is associated with left ventricular diastolic dysfunction due to increased end-diastolic pressure. This increase, through the cardiopulmonary reflexes, can influence autonomic cardiovascular control. METHODS: We assessed autonomic nervous system modulation of cardiovascular signals by power spectral analysis of RR interval and systolic arterial pressure variabilities in subjects with recently diagnosed hypertension with or without diastolic dysfunction and in normotensive control subjects. RESULTS: Both hypertensive groups had higher low-frequency (LF) power expressed in normalized units (NUs) than normotensive controls (p < 0.05; p < 0.001) during controlled breathing at rest. The LF spectral index measured after tilt was greater in hypertensive subjects with diastolic dysfunction than in those without (p < 0.05). LF NUs measured at rest correlated significantly with the E/A wave ratio and after tilt with the E-wave deceleration time. CONCLUSIONS: These results seem to indicate that in subjects with recently diagnosed hypertension sympathetic modulation of the sinus node prevails. During tilt, a maneuver designed to stimulate systemic arterial and cardiopulmonary baroreceptor reflexes, hypertensive subjects with diastolic dysfunction, who presumably also have higher end-diastolic pressures, seem to have greater sympathetic modulation of the sinus node than hypertensive subjects without diastolic dysfunction. 相似文献
994.
Savino F Petrucci E Lupica MM Nanni GE Oggero R 《World journal of gastroenterology : WJG》2011,17(15):1971-1975
AIM: To test if total ghrelin is present in infant formulas. METHODS: Using a radioimmunoassay, we measured total ghrelin concentrations in 19 samples of commercial infant formulas and in 20 samples of human milk. We also determined ghrelin concentration in the serum of infants and lactating mothers. RESULTS: Ghrelin concentrations were significantly higher in artificial milk (2007.1 ± 1725.36 pg/mL) than in human milk (828.17 ± 323.32 pg/mL) (P = 0.005). The mean ghrelin concentration in infant serum (n = ... 相似文献
995.
de Tommaso M Ceci E Pica C Trojano M Delussi M Franco G Livrea P Ruggieri M 《The journal of headache and pain》2012,13(5):389-394
Serum levels of N-acetyl-aspartate (NAA) may be considered a useful marker of neuronal functioning. We aimed to measure serum NAA in cohorts of migraine and tension-type headache patients versus controls, performing correlations with main clinical features. A total of 147 migraine patients (including migraine without aura, with aura and chronic migraine), 65 tension-type headache (including chronic and frequent episodic tension-type headache) and 34 sex- and age-matched controls were selected. Serum was stored at −80 °C. Quantification of NAA was achieved by the standard addition approach and analysis was performed with liquid-chromatography–mass-spectrometry (LC/MS) technique. The NAA levels were significantly decreased in migraine group (0.065 ± 0.019 mol/L), compared with both tension-type headache patients (0.078 ± 0.016 mol/L) and controls (0.085 ± 0.013 mol/L). Control subjects were significantly different from migraine with and without aura and chronic migraine, who differed significantly from episodic and chronic tension-type headache. Migraine with aura patients showed lower NAA levels when compared to all the other headache subtypes, including migraine without aura and chronic migraine. In the migraine group, no significant correlation was found between NAA serum levels, and headache frequency, allodynia and interval from the last and the next attack. The low NAA in the serum may be a sign of neuronal dysfunction predisposing to migraine, probably based on reduced mitochondria function. 相似文献
996.
Oral lichen planus pathogenesis: A role for the HCV-specific cellular immune response 总被引:15,自引:0,他引:15
Pilli M Penna A Zerbini A Vescovi P Manfredi M Negro F Carrozzo M Mori C Giuberti T Ferrari C Missale G 《Hepatology (Baltimore, Md.)》2002,36(6):1446-1452
Hepatitis C virus infection can be associated with different extrahepatic manifestations, including lichen planus; however, no clear role for HCV in their pathogenesis has been established. T cells were isolated from lichen biopsy specimens of 7 HCV positive patients with oral lichen planus. HCV-specific CD4(+) T-cell lines were obtained in 4 patients from lichen lesions but only in 2 of them from the peripheral blood. Different clonal populations were found in oral tissue and peripheral blood of individual patients, as shown by TCR-Vbeta analysis of antigen-specific T cells. Frequency of HCV-specific CD8(+) cells tested with 4 different HCV tetramers was significantly higher in the lichen tissue than in the circulation; moreover, lichen-derived HCV-specific CD8(+) T cells showed the phenotype of recently activated T cells because most of them were CD69(+) and produced interferon gamma (IFN-gamma) but expanded poorly in vitro upon antigen stimulation. The specificity of HCV-reactive T-cell recruitment into the lichen tissue was further confirmed by the absence of HBV-specific T cells within lichen lesions in 3 additional patients with lichen planus associated with HBV infection. Our study shows HCV-specific T-cell responses at the site of the lesions of an HCV-associated dermatologic disease, sustained by HCV-specific T cells with phenotypic and functional characteristics of terminally differentiated effector cells. In conclusion, this finding and the detection of HCV RNA strands in the lichen tissue strongly suggest a role for HCV-specific T-cell responses in the pathogenesis of oral lichen planus associated with HCV infection. 相似文献
997.
Illario M Cavallo AL Monaco S Di Vito E Mueller F Marzano LA Troncone G Fenzi G Rossi G Vitale M 《The Journal of clinical endocrinology and metabolism》2005,90(5):2865-2873
We recently demonstrated in an immortalized thyroid cell line that integrin stimulation by fibronectin (FN) simultaneously activates two signaling pathways: Ras/Raf/MAPK kinase (Mek)/Erk and calcium Ca2+/calcium calmodulin-dependent kinase II (CaMKII). Both signals are necessary to stimulate Erk phosphorylation because CaMKII modulates Ras-induced Raf-1 activity. In this study we present evidence that extends these findings to normal human thyroid cells in primary culture, demonstrating its biological significance in a more physiological cell model. In normal thyroid cells, immobilized FN-induced activation of p21Ras and Erk phosphorylation. This pathway was responsible for FN-induced cell proliferation. Concurrent increase of intracellular Ca2+ concentration and CaMKII activation was observed. Both induction of p21Ras activity and increase of intracellular Ca2+ concentration were mediated by FN binding to alphavbeta3 integrin. Inhibition of the Ca2+/CaMKII signal pathway by calmodulin or CaMKII inhibitors completely abolished the FN-induced Erk phosphorylation. Binding to FN induced Raf-1 and CaMKII to form a protein complex, indicating that intersection between Ras/Raf/Mek/Erk and Ca2+/CaMKII signaling pathways occurred at Raf-1 level. Interruption of the Ca2+/CaMKII signal pathway arrested cell proliferation induced by FN. We also analyzed thyroid tumor cell lines that displayed concomitant aberrant integrin expression and signal transduction. These data confirm that integrin activation by FN in normal thyroid cells generates Ras/Raf/Mek/Erk and Ca2+/CaMKII signaling pathways and that both are necessary to stimulate cell proliferation, whereas in thyroid tumors integrin signaling is altered. 相似文献
998.
Prisco M Marina P Valiante S Salvatore V Maddalena Di Fiore M Maria MD Raucci F Franca R Del Giudice G Giuseppina del G Romano M Maurizio R Laforgia V Vincenza L Limatola E Ermelinda L Andreuccetti P Piero A 《General and comparative endocrinology》2008,157(2):125-132
The influence of 17β-estradiol (E2) on vertebrate vitellogenesis is well ascertained. The aim of the present paper is to study the involvement of E2 and progesterone (P) in the induction and regulation of vitellogenesis in females and experimental E2-treated males of Torpedo marmorata. We analyzed females in various stages of the reproductive cycle and E2 experimentally treated males. The presence of vitellogenin was investigated in the plasma and in the liver by western blot and immunohistochemistry; its site of synthesis was investigated by in situ hybridization. The steroid levels in the plasma were measured by Enzyme Immunoassay. In treated males, E2 induces in the liver the synthesis of VTG which is then secreted into the bloodstream as a 205-kDa polypeptide, the same that is found in the plasma of non-pregnant vitellogenic females. In females, E2 is naturally present in the plasma and its level is correlated with VTG synthesis in the liver and with the female reproductive cycle. Indeed, large amounts of E2 are only found in mature vitellogenic females, whose liver is involved in VTG synthesis and secretion. By contrast, small amounts of E2 are evident in juveniles whose ovaries are lacking in vitellogenic follicles and in females preparing for ovulation. Low titers are also found in gravid females, whose liver is not engaged in VTG synthesis. We show that P, which is absent in untreated males and juvenile females, is evident in the blood serum of E2-treated males and sexually mature females. Interestingly, in treated males P appears in the plasma just 24 h after the first injection of E2 and its titer increases; a week after the last injections, the P level is similar to that recorded in non-gravid vitellogenic females. Finally, it is noteworthy that the highest titer of P was recorded in pregnant females. We demonstrate that in Torpedo vitellogenin synthesis, as in other vertebrates, is under the control of E2 but also that this synthesis is probably under the control of progesterone. 相似文献
999.
Monica Alemany Maria Rosa Hernandez Jordi Bozzo Ana Maria Galan Joan Carles Reverter Roberto Mazzara Antonio Ordinas Gines Escolar 《Vox sanguinis》1997,73(1):36-42
Objectives: Because of the limited life span of platelets in regular storage systems, we were interested in investigating the effects on hemostasis of nonliving platelet derivatives. Methods: We evaluated the effects of different platelet preparations on primary hemostasis in a well-established perfusion model. Studies were carried out with blood anticoagulated with low molecular weight heparin. Similar amounts of frozen-thawed, sonicated or lyophilized platelets were added to normal blood or to blood which had been experimentally depleted of platelets. Platelet interaction with the subendothelium and fibrin deposition were morphometrically evaluated. Results: Addition of nonviable platelet preparations to thrombocytopenic blood always promoted a statistically significant increase in the deposition of fibrin on the subendothelium, but only lyophilized platelets retained some ability to interact with the subendothelium. Flow cytometry studies demonstrated the presence of GPIb, GPIIIa and P-selectin on lyophilized platelets. Conclusions: Preparations containing nonviable platelets may still retain some hemostatic properties. 相似文献
1000.
Francesco Spannella MD Federico Giulietti MD Massimiliano Fedecostante MD Maddalena Ricci MD Paolo Balietti MD Guido Cocci MD Laura Landi MD Anna Rita Bonfigli MSc Massimo Boemi MD Emma Espinosa MD Riccardo Sarzani MD PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2017,19(5):472-478
Patients with type 2 diabetes mellitus are at high risk for atherosclerotic disease, and proper blood pressure measurement is mandatory. The authors examined the prevalence of an interarm difference (IAD) in blood pressure and its association with cardiovascular risk factors and organ damage (nephropathy, retinopathy, left ventricular hypertrophy, and vascular damage) in a large diabetic population. A total of 800 consecutive patients with type 2 diabetes mellitus were evaluated with an automated simultaneous bilateral device (men: 422 [52.8%]; mean age: 68.1±12.2 years). Diabetic patients with systolic IAD ≥5 and systolic IAD ≥10 mm Hg showed an increased risk of having vascular damage (adjusted odds ratios: 1.73 and 2.49, respectively) and higher pulse pressure. IAD is highly prevalent in patients with diabetes, is associated with vascular damage, even for IAD ≥5 mm Hg, and should be accurately obtained to avoid underdiagnosis and undertreatment of hypertension. 相似文献