instruction:
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.
question:
Apelin has been shown ex vivo to be a potent cardiac inotrope. This study was undertaken to evaluate the in vivo effects of apelin on cardiac function in native and ischemic cardiomyopathic rat hearts using a novel combination of a perivascular flow probe and a conductance catheter.', 'Native rats (n =32) and rats in heart failure 6 weeks after left anterior descending coronary artery ligation (n =22) underwent median sternotomy with placement of a perivascular flow probe around the ascending aorta and a pressure volume conductance catheter into the left ventricle. Compared with sham-operated rats, the ligated rats had significantly decreased baseline Pmax and max dP/dt. Continuous infusion of apelin at a rate of 0.01 microg/min for 20 minutes significantly increased Pmax and max dP/dt compared with infusion of vehicle alone in both native and failing hearts. Apelin infusion increased cardiac contractility, indicated by a significant increase in stroke volume (SV) without a change in left ventricular end diastolic volume (102+/-16% change from initial SV versus 26+/-20% for native animals, and 110+/-30% versus 26+/-11% for ligated animals), as well as an increase in preload recruitable stroke work (180+/-24 mm Hg versus 107+/-9 mm Hg for native animals).
answer:
Does apelin have in vivo inotropic effects on normal and failing hearts?

question:
SPARC (secreted protein acidic, rich in cysteine) is a matricellular protein that has been found to be activated in a number of human cancers. More recently, it has been shown to be upregulated in human gastric and colorectal cancer. We therefore wished to address the functional importance of SPARC upregulation to intestinal tumorigenesis in vivo.', 'SPARC upregulation was determined in intestinal adenomas of tumour-prone Apc(Min/+) mice at both the RNA and the protein level. To determine the functional importance of SPARC for intestinal tumorigenesis we then intercrossed Sparc knockout mice with Apc(Min/+) mice (n = 20). Intestinal enterocyte migration was examined using bromodeoxyuridine labelling studies.', 'Levels of murine Sparc and several related proteins were upregulated in adenomas arising in Apc(Min/+) mice. A deficiency of Sparc strongly suppressed adenoma formation in Apc(Min/+) mice (p>or=0.0001). Importantly, a deficiency of Sparc also accelerated enterocyte migration (p = 0.01), as perturbed slow epithelial migration may underpin adenoma formation in the intestine.
answer:
Does deficiency of SPARC suppress intestinal tumorigenesis in APCMin/+ mice?

question:
Physical activity is beneficial for cancer survivors, but exercise participation is low in this population. It is therefore important to understand the psychological factors underlying exercise uptake so that more effective interventions can be developed. Social-cognitive theory constructs such as outcome expectancies predict exercise behavior, but self-report measures have several limitations. We examined the associations between implicit (automatic) cognitions and exercise behavior and self-efficacy in endometrial cancer survivors.', 'This was a longitudinal study to examine predictors of exercise behavior in female endometrial cancer survivors who all received an exercise intervention. Participants (N = 100, mean age of 57.0) completed questionnaires to assess self-report exercise-related measures (outcome expectancy and attitudes about and identification with exercise) and reaction time (RT) tasks to assess implicit exercise cognitions (expectancy accessibility, implicit attitudes about exercise, and implicit self-identification with exercise) at baseline and at 2, 4, and 6 months at follow-up. Exercise behavior was measured using accelerometers and self-report. Data were analyzed using linear mixed models.', 'Expectancy accessibility was associated with exercise duration independent of the corresponding self-report measure. Exercise implicit attitudes and self-identification were prospectively associated with exercise self-efficacy only after adjustment for the corresponding self-report measures and baseline self-efficacy. Self-report measures were also associated with study outcomes.
answer:
Are self-reported and automatic cognitions associated with exercise behavior in cancer survivors?