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:
The role of Kdr (VEGFR-2/Flk-1) in vascular formation has been well described, but the role of Flt1 (VEGFR-1) is not well studied and is generally considered as a decoy receptor for trapping VEGF.', 'The effects of VEGFR1/2 kinase inhibitor (VRI) and calycosin on Flt1 tyrosine kinase (TK) activity were evaluated by molecular docking, enzymatic inhibition assay, protein co-immunoprecipitation and siRNA gene knock-down analysis in HUVECs. Toxicities of the chemicals were examined using HUVECs viability. Their effects on angiogenesis and vessel formation were furthered studied in HUVECs in vitro and Tg(fli-1:EGFP) zebrafish in vivo. The gene and protein expression of VEGF and VEGF receptors were investigated by quantitative RT-PCR and Western blot.', 'VRI strongly inhibited physiological functions of both VEGF receptors and suppressed endothelial cell survival. This resulted in blood vessel loss in zebrafish embryos. Interestingly, calycosin co-treatment impeded VRI-induced blood vessel loss. Docking and kinase inhibition assay revealed that calycosin competed with VRI for the tyrosine kinase domain of Flt1 without affecting ATP binding. On the contrary, calycosin did not affect the interaction between VRI and Kdr-TK. Consistent with these results, calycosin counteracted the inhibition of Flt1-TK and PI3K phosphorylation induced by VRI in HUVECs. Further studies in vitro and in vivo showed that the minimizing effect of calycosin on VRI-mediated endothelial cytotoxicity was blocked by wortmannin (a PI3K inhibitor). The impeding effect of calycosin on VRI-induced blood vessel loss was absent in zebrafish embryos injected with Flt1 MO.
answer:
Is basal Flt1 tyrosine kinase activity a positive regulator of endothelial survival and vascularization during zebrafish embryogenesis?

question:
Despite the clinical efficacy of recombinant human erythropoietin (RHE) on chemotherapy-induced anemia, most cost-effectiveness studies have given unfavorable results.', 'To determine the cost of managing anemia in unselected patients receiving chemotherapy for lung cancer, and the efficacy and cost-effectiveness of RHE.', 'We constructed Markov models of two cohorts of patients who received (n=94) or did not receive (n=89) darbepoetin (one weekly injection when the hemoglobin level fell below 11 g/dl), focusing on changes in hemoglobin levels, transfusion requirements, anemia management costs, and the cost-effectiveness ratios of the two management strategies.', 'The use of RHE significantly reduced the proportion of patients needing transfusions (from 33.6% to 19.1%, p<0.05) and the number of red cell units used by transfusion (from 2.97+/-1.47 to 2.11+/-0.47, p<0.01). Markov modeling showed that the RHE strategy significantly increased the mean Hb level (13+/-0.5 g/dl versus 11.9+/-1g/dl, p<0.001), at the price of an increase in the main cost (respectively, US$ 1732+/-897 and 996+/-643; p<0.01). The cost-effectiveness ratio favored the RHE strategy (7.02 versus 9.04). Sensitivity analysis showed that the RHE strategy remained dominant in most situations.
answer:
Is routine once-weekly darbepoetin alfa administration cost-effective in lung cancer patients with chemotherapy-induced anemia : a Markov analysis?

question:
This study determined the effect of a structured isotonic strength training (ST) program on left ventricular (LV) function (ejection fraction, stroke volume, and end-diastolic and end-systolic volumes) and physical fitness (6-minute walk test, upper body strength, lower body strength, and body composition) in patients with New York Heart Association class II and III heart failure.', 'Sixteen patients were randomized into 2 groups, ST and usual care. The ST group (10 patients) performed 24 ST exercise sessions (3 per week, 8 weeks), while the usual care (6 patients) group followed routine medical care. The structured isotonic ST program involved 12 different exercises on circuit weight machines. LV function (3D echocardiography) and physical fitness were assessed at baseline and 8 weeks.', 'Modest improvements (P < .05) in resting ejection fraction (0.32-0.37) and stroke volume (46 to 53 mL/beat), as well as in muscular strength and 6-minute walk distance, were found after training.
answer:
Does resistance exercise training improve heart function and physical fitness in stable patients with heart failure?