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Twenty-eight HIV patients either naive or failing highly active antiretroviral therapy (HAART)with moderate-advanced Kaposi's sarcoma (KS)were randomly chosen to initiate a new HAART regimen plus pegylated liposomal doxorubicin(PLD) or the new HAART regimen alone. After 48 weeks, better response rates were observed in the HAART plus PLD group (76% versus 20%).In HIV-infected patients with moderate-advanced KS, HAART alone may not be enough for KS response.  相似文献   
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长期以来,一直存在抗高血压药物是否有致癌作用的争议.自从在年龄>50岁的妇女中使用萝芙碱提取物造成乳腺癌发病率增加的报道后[1],这一争议已持续了30年.Sipahi和同事们最近的研究显示:血管紧张素受体拮抗剂(angiotensin receptor-blockers,ARB)有较高的致癌风险.这一发现再次引发了抗...  相似文献   
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Background

Phase contrast velocimetry cardiovascular magnetic resonance (PC-CMR) is a powerful and versatile tool allowing assessment of in vivo motion of the myocardium. However, PC-CMR is sensitive to motion related artifacts causing errors that are geometrically systematic, rendering regional analysis of myocardial function challenging. The objective of this study was to establish an optimized PC-CMR method able to provide novel insight in the complex regional motion and strain of the rodent myocardium, and provide a proof-of-concept in normal and diseased rat hearts with higher temporal and spatial resolution than previously reported.

Methods

A PC-CMR protocol optimized for assessing the motion and deformation of the myocardium in rats with high spatiotemporal resolution was established, and ten animals with different degree of cardiac dysfunction underwent examination and served as proof-of-concept. Global and regional myocardial velocities and circumferential strain were calculated, and the results were compared to five control animals. Furthermore, the global strain measurements were validated against speckle-tracking echocardiography, and inter- and intrastudy variability of the protocol were evaluated.

Results

The presented method allows assessment of regional myocardial function in rats with high level of detail; temporal resolution was 3.2 ms, and analysis was done using 32 circumferential segments. In the dysfunctional hearts, global and regional function were distinctly altered, including reduced global peak values, increased regional heterogeneity and increased index of dyssynchrony. Strain derived from the PC-CMR data was in excellent agreement with echocardiography (r = 0.95, p < 0.001; limits-of-agreement −0.02 ± 3.92%strain), and intra- and interstudy variability were low for both velocity and strain (limits-of-agreement, radial motion: 0.01 ± 0.32 cm/s and −0.06 ± 0.75 cm/s; circumferential strain: -0.16 ± 0.89%strain and −0.71 ± 1.67%strain, for intra- and interstudy, respectively).

Conclusion

We demonstrate, for the first time, that PC-CMR enables high-resolution evaluation of in vivo circumferential strain in addition to myocardial motion of the rat heart. In combination with the superior geometric robustness of CMR, this ultimately provides a tool for longitudinal studies of regional function in rodents with high level of detail.  相似文献   
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Objectives

The aim of the study was to determine whether behaviourally informed short message service (SMS) primer and reminder messages could increase the return rate of HIV self‐sampling kits ordered online.

Methods

The study was a 2 × 2 factorial design randomized control trial. A total of 9585 individuals who ordered a self‐sampling kit from www.freetesting.hiv different SMS combinations: 1) standard reminders sent days 3 and 7 after dispatch (control); 2) primer sent 1 day after dispatch plus standard reminders; 3) behavioural insights (BI) reminders (no primer); or 4) primer plus BI reminders. The analysis was restricted to individuals who received all messages (n = 8999). We used logistic regression to investigate independent effects of the primer and BI reminders and their interaction. We explored the impact of sociodemographic characteristics on kit return as a secondary analysis.

Results

Those who received the primer and BI reminders had a return rate 4% higher than that of those who received the standard messages. We found strong evidence of a positive effect of the BI reminders (odds ratio 1.13; 95% confidence interval 1.04–1.23; P = 0.003) but no evidence for an effect of the primer, or for an interaction between the two interventions. Odds of kit return increased with age, with those aged ≥ 65 years being almost 2.5 times more likely to return the kit than those aged 25–34 years. Men who have sex with men were 1.5–4.5 times more likely to return the kit compared with other sexual behaviour and gender identity groups. Non‐African black clients were 25% less likely to return the kit compared with other ethnicities.

Conclusions

Adding BI to reminder messages was successful in improving return rates at no additional cost.  相似文献   
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