Given a passage, 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.
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Question: Smoking is an important risk factor for cardiovascular disease. Sympathetic responses to cigarette smoking may be implicated in the link between smoking and cardiovascular disease. We tested the hypothesis that the sympathetic neural responses to smoking are age dependent.', 'We examined the effects of cigarette smoking and sham smoking on muscle sympathetic nerve activity, blood pressure and heart rate in 14 normotensive middle-aged (49 +/- 4 years) and 12 young (29 +/- 4 years) habitual smokers matched for body mass index (25 +/- 2 kg/m2 in both groups).', 'Sham smoking had no significant effect on sympathetic drive, blood pressure or heart rate in either group. Cigarette smoking increased heart rate in both middle-aged subjects and young subjects. In comparison to younger subjects, middle-aged smokers showed similar smoking-related increases in systolic blood pressure (SBP) [10 +/- 3 versus 12 +/- 2 mmHg, respectively, not significant (NS)]. Smoking decreased sympathetic nerve activity by 28 +/- 12% of baseline values (P < 0.01) in young subjects. However, muscle sympathetic nerve activity did not change significantly after smoking in middle-aged subjects (5 +/- 8%, NS), despite the increased blood pressures, which would be expected to inhibit sympathetic activity. By contrast, in young subjects, the heart rate increase (22 +/- 2 bpm) was greater than that seen in middle-aged subjects (13 +/- 2 bpm, P < 0.01).

Answer: Are sympathetic neural responses to smoking age dependent?


Question: A fundamental prerequisite for using degradable synthetic biopolymers as composite skin substitutes is the ability to establish vascular tissue. PEGT/PBT block-copolymer matrices have previously been shown as a favorable dermal substitute. In this study, quantitative data on neovascularization of PEGT/PBT block-copolymer matrices are presented.', 'PEGT/PBT-block-copolymer discs of three different pore diameters (1: < 75 microm, 2: 75-212 microm, 3: 250-300 microm) were implanted into dorsal skinfold chambers of balb/c mice. Histological sections were evaluated 7, 14, and 21 days post implantation by light and scanning electron microscopy. Blood vessel analysis was performed by means of digital image analysis (n = 288) of hematoxylin/eosin stained sections within apical (AOF) and basal (BOF) observation fields of the matrices.', 'Twenty-one days after implantation the density of blood vessels within the BOF of the scaffolds with a pore size of 75-212 and 250-300 microm were 4.6 +/- 0.45 and 5.8 +/- 0.62 (mean +/- S.E.M.; blood vessel profiles (BVF)), respectively. In <75 microm scaffolds, smaller numbers of BVF were found (4.2 +/- 0.39). In contrast, the evaluation within the AOF revealed significantly higher numbers of BVF in 75-212 microm group (3.5 +/- 0.49) and 250-300 microm group (4.5 +/- 0.66) as compared to the < 75 microm group (2.3 +/- 0.48).

Answer: Does analysis of neovascularization of PEGT/PBT-copolymer dermis substitute in balb/c-mice?


Question: To examine the role of antiretroviral treatment related perceptions relative to other clinical and psychosocial factors associated with sexual risk taking in HIV positive men who have sex with men (MSM).', 'Participants were recruited from ambulatory HIV clinics in Montreal. Information on sociodemographic factors, health status, antiretroviral treatment related perceptions, and sexual behaviours was collected using a self administered questionnaire. At-risk sexual behaviour was defined as at least one occurrence of unprotected insertive or receptive anal intercourse in the past 6 months. Multivariate logistic regression was performed to evaluate the associations between at-risk sexual behaviour and covariates.', '346 subjects participated in the study. Overall, 34% of subjects were considered at risk; 43% of sexually active subjects (n=274). At-risk sexual behaviour was associated with two antiretroviral treatment related perceptions: (1) taking antiretroviral treatment reduces the risk of transmitting HIV (adjusted odds ratio (OR), 2.10; 95% confidence interval (CI), 1.16 to 3.80); and (2) there is less safer sex practised by MSM because of HIV treatment advances (OR, 1.82; CI, 1.14 to 2.90). Other factors, however, were more strongly associated with risk. These were: (1) safer sex fatigue (OR, 3.23; CI, 1.81 to 5.78); (2) use of "poppers" during sexual intercourse (OR, 6.28; CI, 2.43 to 16.21); and (3) reporting a greater proportion of HIV positive anal sex partners, compared with reporting no HIV positive anal sex partners: (a) <50% HIV positive (OR, 16.79; CI, 4.70 to 59.98); (b) > or =50% HIV positive (OR, 67.67; CI, 15.43 to 296.90).

Answer:
Is hIV status of sexual partners more important than antiretroviral treatment related perceptions for risk taking by HIV positive MSM in Montreal , Canada?