In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: To investigate the role of the anti-cellular immune response in the protection of rhesus macaques against infection with the simian immunodeficiency virus SIVmac. To determine the biological differences between SIV challenge stocks grown either on human T-cell lines or on monkey peripheral blood mononuclear cells (MPBMC).', 'A protective SIVmac split vaccine was administered to rhesus macaques and their anti-, B- and T-cell response monitored. Vaccinees and controls were challenged with SIVmac grown either on human or on monkey cells. The in vivo replication rate of, and the immune response to, the two viruses was compared.', 'Five rhesus macaques were immunized with a total of 2 mg each of purified SIVmac251/32H grown on the human C8166 T-cell line. The antibody and proliferative T-cell responses were evaluated by enzyme-linked immunosorbent assay and T-cell proliferation assay, respectively. Four protected animals and four controls were reboosted and challenged with MPBMC-grown SIVmac251 (SIVmac251/MPBMC). Cell-free virus load was determined by titration of plasma for SIV infectivity on C8166 cells and antigen with a core antigen capture assay.', 'Protection from virus challenge with C8166-grown SIVmac251/32H or SIVmac251/MPBMC did not correlate with anti-cellular antibodies or proliferative T-cell reactivities. Control animals infected with SIVmac251/MPBMC showed high persistent antigenaemia and high plasma virus titres. Both were absent in controls infected with complement C8166-grown SIVmac251/32H. Whereas the latter always seroconverted against the full panel of viral polypeptides, SIVmac251/MPBMC-infected animals showed a drastically decreased antibody response.\Question: Does protection of monkeys by a split vaccine against SIVmac depend upon biological properties of the challenge virus?
Neither the antibody nor the proliferative T-cell response to SIVmac correlates with protection from virus challenge. In contrast to SIVmac251/32H grown on C8166 cells, the MPBMC-grown challenge virus SIVmac251 appears to belong to the 'rapid-high' phenotype, possibly explaining the lack of protection against this SIV.

Context: Remote renal ischemia-reperfusion injury (IRI) following infra-renal aortic occlusion leads to acute kidney injury and systemic inflammation. Hydrogen sulfide is a mediator of IRI and can ameliorate tissue injury in many organ systems. Its role in vascular surgery has yet to be established. We assessed the role of hydrogen sulfide in a rodent model of aortic occlusion.', 'Wistar rats were divided into sham, control, and treatment groups (n = 6). Inflammation was assessed using a nonrecovery protocol. The infra-renal aorta was cross-clamped for 60 min and animals were reperfused for 120 min. Ten minutes before clamp release, treatment animals received hydrogen sulfide (10, 30, or 50 μg/kg) and control animals received 0.9% saline injected into the retroperitoneum. Renal injury and histology were assessed by a recovery protocol. The procedure was identical to the nonrecovery arm but with a single dose of hydrogen sulfide (30 μg/kg) and animals were recovered for 7 days.', 'There was no difference in animal weight between the groups (P = 0.337). In the nonrecovery arm, there was a reduction in serum levels of tumor necrosis factor alpha in sulfide-treated animals compared with controls (909 ± 98 vs. 607 ± 159 pg/mL; P = 0.0038). There was also a reduction in myeloperoxidase-positive cells in renal tissue in the sulfide-treated animals compared with controls (8 ± 4 vs. 17 ± 9; P = 0.03). There was no difference in histological injury score or endothelin-1 levels. In the recovery arm, there was no difference in renal function, Kidney Injury Molecule-1 levels, or histological injury scores.\Question: Does hydrogen sulfide reduce inflammation following abdominal aortic occlusion in rats?
Hydrogen sulfide has systemic and renal anti-inflammatory effects in remote IRI following aortic occlusion in rats.

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

Maximal HR in veteran athletes during specific sporting activities was significantly higher than that attained during a routine sECG. This finding was not sport-specific, nor was it related to the level of competitiveness of the trial participants. These data show that a routine sECG is a submaximal test of exercise performance, and should be interpreted as such.