Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: To explore stakeholder views on cell-free DNA testing and highlight findings important for successful implementation and the provision of best practice in counseling.', 'Noninvasive tests based on the analysis of cell-free fetal DNA are now widely available in clinical practice and applications are expanding rapidly. It is essential that stakeholder views are considered in order to identify and address any ethical and social issues. We provide an overview of stakeholder viewpoints and then focus on the key issues of informed decision making, test uptake, service delivery and information sources.
Answer: Stakeholders are positive about the introduction of cell-free fetal DNA testing into clinical practice. They describe both practical and psychological benefits arising from tests that are safe and can potentially be performed earlier in pregnancy. Key concerns, which include the potential for these tests to have a negative impact on informed decision making and increased societal pressure to have testing, can be addressed through careful parent-directed counseling. As applications for these tests expand it is increasingly important to develop innovative approaches to facilitate good understanding for parents who are offered noninvasive prenatal testing.
Does stakeholder attitudes and need regarding cell-free fetal DNA testing?

Context: The aim of this study was to investigate the association of lipoprotein(a) [Lp(a)] with the severity of coronary heart disease (CHD) in Han Chinese people.', 'Six hundred and seventy-nine patients with angiographically defined CHD were enrolled in this cross-sectional study. Fasting lipids were measured, and the severity of CHD was quantitatively assessed for each patient according to the number of stenotic coronary branches and the Gensini scoring system.', 'The levels of Lp(a), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and apolipoprotein (apo) B100 increased, while high-density lipoprotein cholesterol (HDL-C) and apoAI decreased significantly with the number of stenotic vessels. The levels of Lp(a) increased and HDL-C and apoAI decreased significantly with the Gensini scores. The logistic regression analyses showed that Lp(a) and HDL-C were independently associated with the number of stenotic coronary vessels after adjusting for age, weight, body mass index, sex, smoking, alcohol consumption, hypertension, diabetes, triglycerides, TC, LDL-C, VLDL-C, apoAI, and apoB100. However, only Lp(a) was independently associated with the Gensini scores after adjustment.
Answer: Our data indicate that Lp(a) might be a useful marker in predicting the severity of coronary heart disease.
Are plasma lipoprotein ( a ) levels associated with the severity of coronaryheart disease in Han Chinese people?

Context: Selenium is an essential mineral for immunological function, performing crucial functions at the cellular level. This micronutrient has been determined to be frequently deficient in HIV infected patients, with correlations between reduced immunological function and greater susceptibility to opportunistic infections. Our aim was to evaluate the influence of time of exposure to antiretroviral therapy (ART) on the biochemical profile of selenium in HIV-infected patients.', 'We performed a cross-sectional study on 50 HIV-positive men with different quantitations of viral load and CD4+ T cells, who were either receiving or not receiving ART. Dual energy X-ray absorptiometry (DXA) to determine body composition, biochemical analysis of selenium and albumin, anthropometric measurements were performed. The subjects were divided into groups according to the use of ART or not: The Control Group (CG) was 10 treatment-naïve volunteers, Group G < 2 was 20 volunteers on ART for less than 2 years, and Group G > 2 was 20 volunteers on ART for >2 years.', 'The body mass index showed that all subjects were of normal weight. The group with a longer time of exposure to ART (G > 2) had undetectable viremia and a higher CD4+ T cell count: 593.1 ± 234.6 mm(3). Selenium values (μg/L) were 55.9 ± 11.9 for CG, 52.1 ± 10.5 for G < 2, and 66.9 ± 20.8 for G > 2, with a significant difference between groups G < 2 and G > 2 (p < 0.05), and only G > 2 showed normal selenium values.
Answer: Most of the men studied showed selenium deficiency, except for the subjects with a longer exposure to antiretroviral treatment. Thus, an adequate selenium concentration is related to better control of virology and of immunologic function.

Does a longer time of exposure to antiretroviral therapy improve selenium levels?