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Abstract

An extensive research project is described, during which resentment and hostility were aroused due to the data gathering methods. Those effects disturbed the smooth running of the project and led to subjects withdrawing from some experiments. Although the entire project had many positive features, those that are reported here detracted from its complete success. The negative features should be heeded by others who wish to improve the quality of their experimental work with human beings, otherwise the unintended stress of experimentation might restrict subject participation and disrupt data collection.  相似文献   
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Background: Framingham risk scores (FRS) were validated in a mostly Caucasian population. Evaluation of subclinical atherosclerosis by carotid ultrasound may improve ascertainment of risk in nonwhite populations. This study aimed to evaluate carotid intima‐media thickness (cIMT) and carotid plaquing among Mexican Americans, and to correlate these markers with coronary risk factors and the FRS. Methods/Results: Participants (n = 141) were drawn from the Cameron County Hispanic Cohort. Carotid artery ultrasound was performed and cIMT measured. Carotid plaque was defined as areas of thickening >50% of the thickness of the surrounding walls. Mean age was 53.1 ± 11.7 years (73.8% female). Most were overweight or obese (88.7%) and more than half (53.2%) had the metabolic syndrome. One third (34.8%) had abnormal carotid ultrasound findings (either cIMT ≥75th percentile for gender and age or presence of plaque). Among those with abnormal carotid ultrasound, the majority were classified as being at low 10‐year risk for cardiovascular events. Carotid ultrasound reclassified nearly a third of the cohort as being at high risk. This discordance between 10‐year FRS and carotid ultrasound was noted whether risk was assessed for hard coronary events or global risk. Concordance between FRS and carotid ultrasound findings was best when long‐term (30‐year) risk was assessed and no subject with an abnormal carotid ultrasound was categorized as low risk by the 30‐year FRS algorithm. Conclusions: Integration of carotid ultrasound findings to coronary risk assessments and use of longer term prediction models may provide better risk assessment in this minority population, with earlier initiation of appropriate therapies.  相似文献   
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Purpose: To compare visualization of first trimester fetal anatomic transvaginal ultrasound (TVUS) to the second trimester transabdominal anatomic ultrasound (TAU) in normal weight and obese patients.

Materials and methods: In a prospective cross-sectional study design, 25 women underwent a TVUS between 12 and 14 weeks, and a TAU at 18–22 weeks. For each anatomic structure, the percentage of patients achieving optimal visualization was recorded. Risk ratios for visualizing a structure in the second trimester versus the first were calculated.

Results: Twenty-five patients underwent a TVUS and 24 completed the TAU. The average BMI in the obese and nonobese groups was 34?kg/m2 and 23?kg/m2, respectively. All structures were more consistently visualized during the TAU for the both groups. The cardiac views, hands and feet were more difficult to visualize in all the patients at both scan times but were more frequently visualized in the TAU. For the obese patients, hands, feet, cardiac and spine views were less frequently visualized in both the scans. The posterior fossa and profile views were more difficult to obtain in the TVUS.

Conclusions: The first trimester TVUS detects many of the structures assessed during an anatomic survey; however, it is not superior to the second trimester TAU in normal weight and obese patients.  相似文献   
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More nations are joining the human embryonic stem cell (hESC) ??race?? by aggressively publishing in the peer-reviewed journals. Here we present data on the international use and distribution of hESC using a dataset taken from the primary research literature. We extracted these papers from a comprehensive dataset of articles using hESC and human induced pluripotent stem cells (hiPSC). We find that the rate of publication by US-based authors is slowing in comparison to international labs, and then declines over the final year of the period 2008?C2010. Non-US authors published more frequently and at a significantly higher rate, significantly increasing the number of their papers. In addition, international labs use a more diverse set of hESC lines and Obama-era additions are used more in non-US locations. Even considering the flood of new lines in the US and abroad, we see that researchers continue to rely on a few lines derived before the turn of the century. These data suggest ??embargo?? effects from restrictive policies on the US stem cell field. Over time, non-US labs have freely used lines on the US registries, while federally funded US scientists have been limited to using those lines approved by the NIH.  相似文献   
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