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.

Input: Consider Input: To examine the relationship between sperm strict morphology and sperm chromatin integrity.', 'Prospective study.', 'Infertility clinic.', 'Eighty-seven consecutive semen samples from non-azoospermic men presenting for infertility evaluation and 6 samples from fertile donors.', 'Assessment of standard semen parameters and sperm chromatin structure assay (SCSA) parameters (%DFI [DNA fragmentation index] and %HDS [high DNA stainability]). Evaluation of %HDS and %DFI after treatment with dithiothreitol (a thiol-reducing agent used to decondense sperm nuclei) was also undertaken.', 'Relationship between sperm strict morphology defects and SCSA parameters (%DFI and %HDS).', 'We observed significant relationships between the percentage of normal sperm forms and both %HDS (r = -0.40) and sperm motility (r = 0.32). We also found significant relationships between sperm head defects and both %HDS (r = 0.40) and sperm concentration (r = -0.39). Sperm tail, midpiece, and neck defects were not significantly related to the SCSA parameters. Treatment of spermatozoa with dithiothreitol (to induce decondensation) resulted in a substantial increase in %HDS but no measurable change in %DFI.

Output: Is sperm head morphology related to high deoxyribonucleic acid stainability assessed by sperm chromatin structure assay?


Input: Consider Input: The stress electrocardiogram (sECG) is routinely used to screen individuals for underlying cardiac pathology before an exercise programme is prescribed. The underlying assumption is that the cardiac responses elicited during the sECG test are similar to those achieved during participation in sporting activities. However, this premise may be incorrect since the physical demands of different modes of exercise vary substantially.', "Ten veteran league squash players (LSP), 10 social squash players (SSP), 10 league runners (LR), 10 social runners (SR) and 10 sedentary individuals (SED) were recruited for the study. All subjects completed a lifestyle questionnaire, a full medical examination and a routine sECG. Thereafter each subject's heart rate (HR) was monitored on two separate occasions while participating in sporting activity.", 'No sECG exercise-induced abnormalities were observed, although five subjects showed resting abnormalities. Maximal HR during the sECG, and maximal and mean HR during the field tests, were not significantly different between groups. However, maximal HR was significantly higher in all groups during their sporting activities than during stress testing in the laboratory (P < 0.01).

Output: Do veteran athletes exercise at higher maximum heart rates than are achieved during standard exercise ( stress ) testing?


Input: Consider Input: It has been shown that vitamin A supplementation has different effects on skeletal health and the antioxidant system. Deficiency or excess of this vitamin can lead to health problems. Vitamin A can work as either an antioxidant or prooxidant depending on its concentration. The present study was conducted to investigate the effects of different doses of vitamin A supplementation on the antioxidant system in rats.', 'Forty Spargue-Dawley male rats were divided into four groups according to the dose of vitamin A received: 0 (A0), 4,000 (A1), 8,000 (A2), and 20,000 (A3) IU retinyl palmitate/kg diet. After a feeding period of 4 wks, lipid peroxide levels, glutathione concentration, antioxidant enzyme activities, and vitamins A and E concentrations were measured. Histopathological changes were observed in rat liver tissue using an optical microscope and transmission electron microscope.', 'Lipid peroxide levels in plasma were significantly decreased in the A1 and A2 groups compared to the A0 rats. Erythrocyte catalase and hepatic superoxide dismutase activities of the A2 group were significantly higher than those of the A0 group. Hepatic glutathione peroxidase activity was significantly lower in the A3 group compared to the other groups. Total glutathione concentrations were significantly higher in the A1 and A2 groups than in the A0 group. Histological examination of liver tissue showed that excessive supplementation of vitamin A might lead to lipid droplet accumulation and nuclear membrane deformation.


Output: Does vitamin A supplementation modify the antioxidant system in rats?