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Mauro Gentile Alessandro De Vito Cristiano Azzini Carmine Tamborino Ilaria Casetta 《Ultrasound in medicine & biology》2014,40(11):2637-2641
Contrast-transcranial Doppler and contrast-transcranial color-coded duplex sonography (c-TCCD) have been reported to have high sensitivity in detecting patent foramen ovale as compared with transesophageal echocardiography. An international consensus meeting (Jauss and Zanette 2000) recommended that the contrast agent for right-to left-shunt (RLS) detection using contrast-transcranial Doppler be prepared by mixing 9 mL of isotonic saline solution and 1 mL of air. The aim of our study was to determine whether adding blood to the contrast agent results in improved detection of RLS. We enrolled all consecutive patients admitted to our neurosonology laboratory for RLS diagnosis. For each patient, we performed c-TCCD both at rest and during the Valsalva maneuver using two different contrast agents: ANSs (1 mL of air mixed with 9 mL of normal saline) and ANSHBs (1 mL of air mixed with 8 mL of normal saline and 1 mL of the patient's blood). To classify RLS, we used a four-level visual categorization: (i) no occurrence of micro-embolic signals; (ii) grade I, 1–10 signals; (iii) grade II, >10 signals but no curtain; grade III, curtain pattern. We included 80 patients, 33 men and 47 women. RLS was detected in 18.8% at rest and in 35% during the Valsalva maneuver using ANSs, and in 31.3% and in 46.3% using ANSHBs, respectively (p < 0.0001). There was a statistically significant increase in the number of micro-embolic signals with the use of ANSHBs. The use of blood mixed with saline solution and air as a c-TCCD contrast agent produced an increase in positive tests and a higher grade of RLS compared with normal saline and air alone, either with or without the Valsalva maneuver. 相似文献
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Factors affecting difficult peripheral intravenous cannulation in adults: a prospective observational study
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Ned L. Cooney Judith L. Cooney Bridget L. Perry Michael Carbone Emily H. Cohen Howard R. Steinberg David T. Pilkey Kevin Sevarino Cheryl A. Oncken & Mark D. Litt 《Addiction (Abingdon, England)》2009,104(9):1588-1596
Aims The primary aim was to compare the efficacy of smoking cessation treatment using a combination of active nicotine patch plus active nicotine gum versus therapy consisting of active nicotine patch plus placebo gum in a sample of alcohol-dependent tobacco smokers in an early phase of out-patient alcohol treatment. A secondary aim was to determine whether or not there were any carry-over effects of combination nicotine replacement on drinking outcomes.
Design Small-scale randomized double-blind placebo-controlled clinical trial with 1-year smoking and drinking outcome assessment.
Setting Two out-patient substance abuse clinics provided a treatment platform of behavioral alcohol and smoking treatment delivered in 3 months of weekly sessions followed by three monthly booster sessions.
Participants Participants were 96 men and women with a diagnosis of alcohol abuse or dependence and smoking 15 or more cigarettes per day.
Intervention All participants received open-label transdermal nicotine patches and were randomized to receive either 2 mg nicotine gum or placebo gum under double-blind conditions.
Findings Analysis of 1-year follow-up data revealed that patients receiving nicotine patch plus active gum had better smoking outcomes than those receiving patch plus placebo gum on measures of time to smoking relapse and prolonged abstinence at 12 months. Alcohol outcomes were not significantly different across medication conditions.
Conclusions Results of this study were consistent with results of larger trials of smokers without alcohol problems, showing that combination therapy (nicotine patch plus gum) is more effective than monotherapy (nicotine patch) for smoking cessation. 相似文献
Design Small-scale randomized double-blind placebo-controlled clinical trial with 1-year smoking and drinking outcome assessment.
Setting Two out-patient substance abuse clinics provided a treatment platform of behavioral alcohol and smoking treatment delivered in 3 months of weekly sessions followed by three monthly booster sessions.
Participants Participants were 96 men and women with a diagnosis of alcohol abuse or dependence and smoking 15 or more cigarettes per day.
Intervention All participants received open-label transdermal nicotine patches and were randomized to receive either 2 mg nicotine gum or placebo gum under double-blind conditions.
Findings Analysis of 1-year follow-up data revealed that patients receiving nicotine patch plus active gum had better smoking outcomes than those receiving patch plus placebo gum on measures of time to smoking relapse and prolonged abstinence at 12 months. Alcohol outcomes were not significantly different across medication conditions.
Conclusions Results of this study were consistent with results of larger trials of smokers without alcohol problems, showing that combination therapy (nicotine patch plus gum) is more effective than monotherapy (nicotine patch) for smoking cessation. 相似文献
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Libani IV Guy EC Melchiori L Schiro R Ramos P Breda L Scholzen T Chadburn A Liu Y Kernbach M Baron-Lühr B Porotto M de Sousa M Rachmilewitz EA Hood JD Cappellini MD Giardina PJ Grady RW Gerdes J Rivella S 《Blood》2008,112(3):875-885
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder. 相似文献