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排序方式: 共有4803条查询结果,搜索用时 15 毫秒
81.
82.
Matias Trillini Monica Cortinovis Piero Ruggenenti Jorge Reyes Loaeza Karen Courville Claudia Ferrer-Siles Silvia Prandini Flavio Gaspari Antonio Cannata Alessandro Villa Annalisa Perna Eliana Gotti Maria Rosa Caruso Davide Martinetti Giuseppe Remuzzi Norberto Perico 《Journal of the American Society of Nephrology : JASN》2015,26(5):1205-1214
Secondary hyperparathyroidism contributes to post-transplant CKD mineral and bone disorder. Paricalcitol, a selective vitamin D receptor activator, decreased serum parathyroid hormone levels and proteinuria in patients with secondary hyperparathyroidism. This single-center, prospective, randomized, crossover, open-label study compared the effect of 6-month treatment with paricalcitol (1 μg/d for 3 months and then uptitrated to 2 µg/d if tolerated) or nonparicalcitol therapy on serum parathyroid hormone levels (primary outcome), mineral metabolism, and proteinuria in 43 consenting recipients of renal transplants with secondary hyperparathyroidism. Participants were randomized 1:1 according to a computer-generated sequence. Compared with baseline, median (interquartile range) serum parathyroid hormone levels significantly declined on paricalcitol from 115.6 (94.8–152.0) to 63.3 (52.0–79.7) pg/ml (P<0.001) but not on nonparicalcitol therapy. At 6 months, levels significantly differed between treatments (P<0.001 by analysis of covariance). Serum bone-specific alkaline phosphatase and osteocalcin decreased on paricalcitol therapy only and significantly differed between treatments at 6 months (P<0.001 for all comparisons). At 6 months, urinary deoxypyridinoline-to-creatinine ratio and 24-hour proteinuria level decreased only on paricalcitol (P<0.05). L3 and L4 vertebral mineral bone density, assessed by dual-energy x-ray absorption, significantly improved with paricalcitol at 6 months (P<0.05 for both densities). Paricalcitol was well tolerated. Overall, 6-month paricalcitol supplementation reduced parathyroid hormone levels and proteinuria, attenuated bone remodeling and mineral loss, and reduced eGFR in renal transplant recipients with secondary hyperparathyroidism. Long-term studies are needed to monitor directly measured GFR, ensure that the bone remodeling and mineral effects are sustained, and determine if the reduction in proteinuria improves renal and cardiovascular outcomes. 相似文献
83.
Cardiac regeneration. 总被引:5,自引:0,他引:5
Piero Anversa Annarosa Leri Jan Kajstura 《Journal of the American College of Cardiology》2006,47(9):1769-1776
The role and even the existence of new myocyte formation in the adult heart remain controversial. Documentation of cell cycle regulators, deoxyribonucleic acid synthesis, and mitotic images has only in part modified the view that myocardial growth can be accomplished exclusively from hypertrophy of an irreplaceable population of differentiated myocytes. However, myocyte regeneration and death occur physiologically, and these cellular processes are enhanced in pathologic states. These observations have challenged the view of the heart as a postmitotic organ and have proposed a new paradigm in which parenchymal and non-parenchymal cells are continuously replaced by newly formed younger populations of myocytes as well as by vascular smooth muscle and endothelial cells. Heart homeostasis is regulated by a stem cell compartment characterized by multipotent cardiac stem cells that possess the ability to acquire the distinct cell lineages of the myocardium. Similarly, adult bone marrow cells are able to differentiate into cells beyond their own tissue boundary and create cardiomyocytes and coronary vessels. This process has been termed developmental plasticity or transdifferentiation. Because of these properties, bone marrow cells and cardiac stem cells have been employed experimentally in the reconstitution of dead myocardium after infarction. These cell classes hold promise for the treatment of heart failure in humans. 相似文献
84.
85.
Cicoira M Rossi A Bonapace S Zanolla L Golia G Franceschini L Caruso B Marino PN Zardini P 《Journal of cardiac failure》2004,10(5):403-411
BACKGROUND: In chronic heart failure (CHF), changes in the extracellular space contribute to cardiac dysfunction. We aimed to determine whether aminoterminal-propeptide of type III procollagen (PIIINP), a marker of extracellular matrix turnover, might provide prognostic information in CHF patients. METHODS AND RESULTS: A total of 101 consecutive CHF patients (mean age 61.7 +/- 8.7 years, 88% males) were followed up between 1999 and 2001. The combined endpoint of the study was death and hospitalization for heart failure. During follow-up there were 15 deaths and 11 hospitalizations for worsening heart failure. At the survival analysis, age (P = .02), New York Heart Association class (P = .014), s-creatinine (P = .014), plasma-PIIINP (p-PIIINP) levels (P = .005), left ventricular ejection fraction (LVEF) (P = .0002), and a restrictive mitral filling pattern (P = .0003) predicted event-free survival. At the multivariate analysis, p-PIIINP levels predicted outcome independently of other clinical variables, hormones, and echocardiographic and exercise testing variables (P < .05 in all models). In patients with LVEF <31%, the presence of p-PIIINP >4.7 microg/L levels was significantly associated with a higher risk of death and hospitalization as compared with the other patients (event-free survival rate at 12 months: 45% versus 95%; at 24 months: 27% versus 88%; at 36 months: 18% versus 85%, P < .0001). CONCLUSIONS: In patients with CHF, PIIINP levels predict outcome independently of clinical status, hemodynamics and hormonal activation. PIIINP levels provide additional prognostic information to that of left ventricular function alone, suggesting that it may reflect more than cardiac extracellular matrix turnover. 相似文献
86.
Luigi Meloni Maria Francesca Marchetti Cristina Cacace Michela Congia Roberta Scotto Piero Caddeo Roberta Montisci 《Journal of electrocardiology》2018,51(6):1131-1134
Background
Pathological Q waves (QWs) in the first ECG recorded at hospital admission has been found to correlate with myocardial damage and mortality in STEMI patients. We investigated the association between new QWs recorded in the pre-hospital setting and adverse outcome during the hospital stay.Methods
A pre-hospital ECG was recorded in 248 patients with STEMI who underwent primary PCI. Patients were divided into two groups based on the presence (n?=?44, QWs) or absence (n?=?204, non-QWs) of new QWs.Results
Patients with new QWs had a higher prevalence of anterior infarct, cardiogenic shock and a lower LV ejection fraction. In-hospital mortality was higher in patients with new QWs. The percentage of patients with new QWs increased progressively with increasing pain to ECG time.Conclusions
New QWs provide rapid prognostic information in the pre-hospital phase of STEMI by identifying patients at risk of adverse outcome during the hospital stay. 相似文献87.
88.
89.
Carla Stecco Piero Pavan Paola Pachera Raffaele De Caro Arturo Natali 《Surgical and radiologic anatomy : SRA》2014,36(1):25-32
The mechanical properties of deep fasciae strongly affect muscular actions, development of pathologies, such as acute and chronic compartment syndromes, and the choice of the various fascial flaps. Actually, a clear knowledge of the mechanical characterization of these tissues still lacks. This study focuses attention on experimental tests of different regions of human crural fascia taken from an adult frozen donor. Tensile tests along proximal–distal and medial–lateral direction at a strain rate of 120 %/s were performed at the purpose of evaluating elastic properties. Viscous phenomena were investigated by applying incremental relaxation tests at total strain of 7, 9 and 11 % and observing stress decay for a time interval of 240 s. The elastic response showed that the fascia in the anterior compartment is stiffer than in the posterior compartment, both along the proximal–distal and medial–lateral directions. This result can explain why the compartment syndromes are more frequent in this compartment with respect to posterior one. Furthermore, the fascia is stiffer along the proximal–distal than along medial–lateral direction. This means that the crural fascia can adapt to the muscular variation of volume in a transversal direction, while along the main axis it could be considered as a structure that contributes to transmitting the muscular forces at a distance and connecting the different segments of the limb. The stress relaxation tests showed that the crural fascia needs 120 s to decrease stress of 40 %, suggesting a similar time also in the living so that the static stretching could have an effect on the fascia. 相似文献
90.
Chiara De Cassan Edoardo Savarino Piero Marson Tiziana Tison Giorgia Hatem Giacomo Carlo Sturniolo Renata D’Incà 《World journal of gastroenterology : WJG》2014,20(45):17155-17162
AIM:To evaluate whether the effectiveness of Granulomonocyto apheresis(GMA),a technique that consists of the extracorporeal removal of granulocytes and monocytes from the peripheral blood,might vary according to the severity of ulcerative colitis(UC)in patients with mild to moderate-severe disease UC activity.METHODS:We retrospectively reviewed prospectively collected data of patients undergoing GMA at our inflammatory bowel disease centre who had at least a 6 mo of follow-up.The demographics,clinical and laboratory data were extracted from the patients’charts and electronic records.The severity of UC was scored according to the Modified Truelove Witts Severity Index(MTWSI).A clinical response was defined as a decrease from baseline of≥2 points or a value of MTWSI≤2 points.RESULTS:A total of 41(24 males/17 females;meanage 47 years)patients were included in the study.After GMA cycle completion,21/28(75%)of mild UC patients showed a clinical response compared with 7/13(54%)of patients with moderate to severe disease(P=0.27).At 6-mo,14/28(50%)of the mild UC patients maintained a clinical response compared with 2/13(15%)of the patients with moderate to severe disease(P=0.04).After the GMA cycle completion and during the 6-mo follow up period,13/16(81%)and 9/16(56%)of mild UC patients with intolerance,resistance and contraindications to immunosuppressants and/or biologics showed a clinical response compared with 2/6(33%)and 0/6(0%)of patients with moderate to severe disease activity with these characteristics(P=0.05and P=0.04,respectively).CONCLUSION:Patients with mild UC benefit from GMA more than patients with moderate to severe disease in the short-term period.GMA should be considered a valid therapeutic option in cases of contraindications to immunosuppressants,corticosteroids and/or biologics. 相似文献