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191.
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193.
The aim of this study was to evaluate the influence of clinic and ambulatory blood pressure (BP) on the occurrence of new‐onset atrial fibrillation (AF) in treated hypertensive patients. We studied 2135 sequential treated hypertensive patients aged >40 years. During the follow‐up (mean 9.7 years, range 0.4–20 years), 116 events (new‐onset AF) occurred. In univariate analysis, clinic, daytime, nighttime, and 24‐h systolic BP were all significantly associated with increased risk of new‐onset AF, that is, hazard ratio (95% confidence interval) per 10 mm Hg increment 1.22 (1.11–1.35), 1.36 (1.21–1.53), 1.42 (1.29–1.57), and 1.42 (1.26–1.60), respectively. After adjustment for various covariates in multivariate analysis, clinic systolic BP was no longer associated with increased risk of new‐onset AF, whereas daytime, nighttime, and 24‐h systolic BP remained significantly associated with outcome, that is, hazard ratio (95% confidence interval) per 10 mm Hg increment 1.09 (0.97–1.23), 1.23 (1.10–1.39), 1.16 (1.03–1.31), and 1.22 (1.06–1.40), respectively. Daytime, nighttime, and 24‐h systolic BP are superior to clinic systolic BP in predicting new‐onset AF in treated hypertensive patients. Future studies are needed to evaluate whether a better control of ambulatory BP might be helpful in reducing the occurrence of new‐onset AF.  相似文献   
194.
Background and AimsOlder patients with metastatic pancreatic adenocarcinoma (MPDAC) are under-represented in clinical trials.MethodsOur single-center, retrospective study enrolled MPDAC patients ≥ 70 treated with chemotherapyResults105 patients were divided in groups based on the received treatments: 44 gemcitabine or capecitabine monotherapy (A), 34 nabpaclitaxel-gemcitabine (B) 27 4-drugs combinations (gemcitabine, cisplatin, capecitabine plus either nab-paclitaxel or epirubicin or docetaxel) (C). Group A: median age was 78 (70–87) and Karnofsky performance status (KPS) ≥80 was found in 84% of patients; Group B: median age 77 (71–84) and KPS ≥ 80 in 88% of patients; Group C: median age 73 (70–78) and KPS ≥ 80 in 93% of patients. Median OS was 7.9, 11.7 and 14.2 months in group A, B and C respectively; 1 and 2-year OS were 27% and 8% in group A; 44% and 5% in group B; 52% and 22% in group C. When lung metastatic only patients were excluded, patients <75 and ≥ 75 had similar OS in group A (6.4 vs 5.6 months) and in group B (12.3 vs 11.1 months). In group B grade 3 thrombocytopenia, fatigue and peripheral neuropathy were more frequent in patients ≥ 75.ConclusionsIn older patients, combination chemotherapy shows acceptable feasibility and promising efficacy.  相似文献   
195.
Women exhibit less burden of anatomic obstructive coronary atherosclerotic disease as compared with men of the same age, but contradictorily show similar or higher cardiovascular mortality rates. The higher prevalence of nonexertional cardiac symptoms and nonobstructive coronary atherosclerotic disease in women may lead to lack of recognition and appropriate management, resulting in undertesting and undertreatment. Leaders in women’s health from the American College of Cardiology’s Cardiovascular Disease in Women Committee present novel imaging cases that may provoke thought regarding the broad clinical spectrum of myocardial infarction and ischemia with nonobstructive coronary arteries in women. These unique imaging approaches are based on the concept of targeting sex-specific differences in acute and stable ischemic heart disease.  相似文献   
196.
Romeo  V.  Sarno  L.  Volpe  A.  Ginocchio  M. I.  Esposito  R.  Mainenti  P. P.  Petretta  M.  Liuzzi  R.  D’Armiento  M.  Martinelli  P.  Brunetti  A.  Maurea  S. 《Abdominal imaging》2019,44(10):3398-3407
Purpose

To compare the performance US and MR in identifying placental adhesion spectrum (PAS) in placenta previa (PP) and to establish a potential method of image interpretation.

Methods

US and MR examinations of 51 patients with PP were selected. The presence of imaging signs commonly used to detect PAS was assessed. Penalized logistic regression was performed considering histology as standard of reference; only signs statistically significant (p < 0.05) were considered for ROC and multivariate analysis. The probability of PAS according to the presence of US and/or MR signs was then assessed.

Results

At univariate analysis, loss of retroplacental clear space, myometrial thinning (MT) and placenta lacunar spaces on US, intraplacental dark bands (IDBs), focal interruption of myometrial border (FIMB) and abnormal vascularity (AV) on MR were statistically significant (p < 0.01). Three diagnostic methods for PAS were then developed for both US and MR when at least one (Method 1), two (Method 2) or three (Method 3) imaging signs occurred, respectively. Method 2 for MR showed a significantly (p < 0.05) higher accuracy (91%) compared to the other methods. When MR IDBs and AV as well as IDBs and FIMB were present in combination with US MT the probability of PAS increased from 75 to 90% and from 80 to 91%, respectively.

Conclusion

MR demonstrated a higher diagnostic accuracy than US to detect PAS. However, since the combination of MR and US signs could improve the probability to detect PAS, a complementary diagnostic role of these techniques could be considered.

  相似文献   
197.
Calsequestrin is a high-capacity Ca-binding protein expressed inside the sarcoplasmic reticulum (SR), an intracellular Ca release and storage organelle in muscle. Mutations in the cardiac calsequestrin gene (CSQ2) have been linked to arrhythmias and sudden death. We have used Ca-imaging and patch-clamp methods in combination with adenoviral gene transfer strategies to explore the function of CSQ2 in adult rat heart cells. By increasing or decreasing CSQ2 levels, we showed that CSQ2 not only determines the Ca storage capacity of the SR but also positively controls the amount of Ca released from this organelle during excitation-contraction coupling. CSQ2 controls Ca release by prolonging the duration of Ca fluxes through the SR Ca-release sites. In addition, the dynamics of functional restitution of Ca-release sites after Ca discharge were prolonged when CSQ2 levels were elevated and accelerated in the presence of lowered CSQ2 protein levels. Furthermore, profound disturbances in rhythmic Ca transients in myocytes undergoing periodic electrical stimulation were observed when CSQ2 levels were reduced. We conclude that CSQ2 is a key determinant of the functional size and stability of SR Ca stores in cardiac muscle. CSQ2 appears to exert its effects by influencing the local luminal Ca concentration-dependent gating of the Ca-release channels and by acting as both a reservoir and a sink for Ca in SR. The abnormal restitution of Ca-release channels in the presence of reduced CSQ2 levels provides a plausible explanation for ventricular arrhythmia associated with mutations of CSQ2.  相似文献   
198.
Hepatitis C virus (HCV) infection is highly prevalent in haemodialysis patients. To date, only a few studies involving a small number of subjects have characterized HCV-infected dialysis patients by serotyping. The spread of HCV serotypes in 114 HCV-positive dialysis patients from the same geographical area was evaluated by Murex HCV serotyping assay. Serotypes were detected in 102 subjects (89.5%), with type 1 being the most frequent (37.7%), followed by types 2 (19.3%), 4 (8.8%) and 3 (7.9%). Types 5 and 6 were the least prevalent (3.5%). Ten samples (8.8%) revealed mixed infections: type 1 was detectable in all and the co-infecting HCV types were types 2, 3 and 4 in 3, 4 and 3 cases, respectively. These results suggest that the serotyping assay as an alternative method of distinguishing the major types of HCV, also for particular risk groups and especially in laboratories that lack the specific expertise to perform genotyping methods. Age-related differences in patients with type 5 compared with those with types 3 and 6 may provide evidence of a more recent spread of these latter types.  相似文献   
199.
OBJECTIVE: To investigate the correlation between plasma concentration of total homocysteine and pulmonary involvement in patients with limited or diffuse scleroderma (systemic sclerosis, SSc). METHODS: Seventy-one patients with scleroderma were divided into 3 groups based on pulmonary involvement: Group A comprised patients without lung involvement (9 cases); Group B patients with lung involvement of mild and moderate stages (44 cases); and Group C patients with lung involvement of severe stage and endstage (18 cases). At the time of evaluation of lung involvement all patients underwent determination of plasma homocysteine concentration. Homocysteine concentration was also measured in 30 healthy controls homogeneous for sex and age. RESULTS: In patients with scleroderma the homocysteine concentration was significantly higher than in controls (11.1 and 6.9 micromol/l, respectively; p < 0.001). We found a significant association between plasma homocysteine concentration and severity of lung involvement that was not modified by correction for age, time from the diagnosis, type of scleroderma pattern, and serum creatinine and folate levels. Homocysteine concentration progressively increases in scleroderma patients with more severe pulmonary involvement. Subjects with high homocysteine concentration (i.e., > or = 75th percentile of homocysteine concentration in patients with scleroderma without lung involvement) were mostly present in the group with the greatest lung involvement. CONCLUSION: High level of homocysteinemia is associated with an increased risk of pulmonary disease in patients with scleroderma. We hypothesize that hyperhomocysteinemia may worsen injury of the endothelium, a key lesion in scleroderma disease, favoring the development of lung involvement. Our data support the hypothesis that homocysteine could be involved in the pathogenetic process of scleroderma pulmonary involvement.  相似文献   
200.
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