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.

Q: To determine whether activin A concentrations are altered in chronic fetal hypoxemia and intrauterine fetal growth restriction (IUGR).', 'In vivo animal experimental model.', 'Department of Physiology, Monash University.', 'Chronically catherised fetal sheep in late pregnancy.', 'Chronic fetal hypoxia and IUGR were experimentally induced by single umbilical artery ligation (SUAL) in catheterised fetal sheep. Maternal and fetal blood samples and amniotic fluid (AF) samples were collected during surgery and thereafter on alternate days, until the time of delivery for analyte measurement. Fetal blood gas parameters were measured daily.', 'Plasma and AF was used to analyse activin A, prostaglandin E2 (PGE2) and cortisol and fetal blood gas analysis was undertaken in whole blood.', 'SUAL produced asymmetric IUGR and non-acidaemic chronic fetal hypoxia and resulted in preterm labour (129 [3] days). AF activin A concentrations were 10-fold higher in the SUAL group than in controls whereas levels in the fetal and maternal circulations were similar between groups.

A: Does chronic fetal hypoxia increase activin A concentrations in the late-pregnant sheep?
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Q: Corticotropin-releasing factor (CRF) is the primary physiologic regulator of the hypothalamic-pituitary-adrenal (HPA) axis and serves to globally coordinate the mammalian stress response. Hyperactivity of central nervous system CRF neurotransmission, acting primarily via the CRF(1) receptor, has been strongly implicated in the pathophysiology of depression and anxiety. Furthermore, there is evidence of enhanced CRF transcription, release, and neuronal activity after the administration of and withdrawal from several drugs of abuse, including cannabis, cocaine, ethanol, and morphine. Treatment with CRF antagonists has been demonstrated to reduce the severity of certain drug withdrawal symptoms, implicating a specific role for activation of CRF neurons in mediating the anxiogenic and stress-like reactions observed after abrupt drug discontinuation.', 'To extend these findings, we investigated whether pretreatment with the selective CRF(1) receptor antagonist R121919 decreases the behavioral and neuroendocrine activation observed after the precipitation of benzodiazepine (BZ) withdrawal in BZ-dependent rats.', 'Pretreatment with R121919 attenuated the subsequent HPA axis activation, behavioral measures of anxiety, and expression of the CRF gene in the paraventricular nucleus of the hypothalamus, as measured by CRF heteronuclear RNA, which occurs after flumazenil-precipitation of withdrawal from the BZ, lorazepam.

A: Does the CRF1 receptor antagonist R121919 attenuate the neuroendocrine and behavioral effects of precipitated lorazepam withdrawal?
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Q: Closed suction drains have an important role in surgical wound healing. Although most surgeons use them routinely, indications for use and their postoperative management (emptying, removal) vary. The purpose of this study was to assess drain use by head and neck surgeons in Canada, to conduct a biomechanical analysis of the drains in a laboratory setting, and to make recommendations for drain use and management.', 'A survey was mailed to 343 active members of the Canadian Society of Otolaryngology. Three sets of experimental trials were conducted on the most commonly used drains to assess the effect of increased reservoir filling on suction generated through (1) incrementally increasing the amount of fluid within the reservoir, (2) compression of the reservoir with no fluid within, and (3) compression with the reservoirs while filled to 25% capacity with fluid.', 'A 41% response rate was obtained. It was found that the majority of head and neck surgeons in Canada use Hemovac and Jackson-Pratt drainage systems routinely. There is considerable variability in practice with regard to drain emptying and timing of removal. Experimental results indicate that as filling of the reservoir increases, suction generated decreases sharply, to between 13 and 20% of initial values at 50% capacity.

A:
Does survey of the use of suction drain in head and neck surgery and analysis of their biomechanical properties?
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