instruction:
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.
question:
Context: High arginase-1 (Arg) expression by myeloid-derived suppressor cells (MDSC) is known to inhibit antitumor T-cell responses through depletion of l-arginine. We have previously shown that nitric oxide (NO), an immune mediator produced from l-arginine, is a potent radiosensitizer of hypoxic tumor cells. This study therefore examines whether Arg(+) overexpressing MDSC may confer radioresistance through depleting the substrate for NO synthesis.', 'MDSC and Arg expression were studied in preclinical mouse CT26 and 4T1 tumor models and further validated in rectal cancer patients in comparison with healthy donors. The radioprotective effect of MDSC was analyzed in hypoxic tumor cells with regard to l-arginine depletion.', 'In both mouse tumors and cancer patients, MDSC expansion was associated with Arg activation causing accelerated l-arginine consumption. l-Arginine depletion in turn profoundly suppressed the capacity of classically activated macrophages to synthesize NO resulting in impaired tumor cell radiosensitivity. In advanced cT3-4 rectal cancer, circulating neutrophils revealed Arg overexpression approaching that in MDSC, therefore mounting a protumor compartment wherein Arg(+) neutrophils increased from 17% to over 90%.\Question: Do myeloid-derived suppressor cells reveal radioprotective properties through arginase-induced l-arginine depletion?
answer:
Protumor Arg(+) MDSC reveal a unique ability to radioprotect tumor cells through l-arginine depletion, a common mechanism behind both T-cell and macrophage inhibition.

question:
Context: To assess how different imputation methods used to account for missing variance data in primary studies influence tests of heterogeneity and pooled results from a meta-analysis with continuous outcomes.', 'Point and variance estimates for changes in serum creatinine, glomerular filtration rate, systolic blood pressure, and diastolic blood pressure were variably reported among 48 primary longitudinal studies of living kidney donors (71%-78% of point estimates were reported, 8%-13% of variance data were reported). We compared the results of meta-analysis, which either were restricted to available data or used four methods to impute missing variance data. These methods used reported P-values, reported nonparametric summaries, results from other similar studies using multiple imputation, or results from estimated correlation coefficients.', 'Significant heterogeneity was present in all four outcomes regardless of the imputation methods applied. The random effects point estimates and 95% confidence intervals varied little across imputation methods, and the differences were not clinically significant.\Question: Do imputing variance estimates alter the conclusions of a meta-analysis with continuous outcomes : a case study of changes in renal function after living kidney donation?
answer:
Different methods to impute the variance data in the primary studies did not alter the conclusions from this meta-analysis of continuous outcomes. Such reproducibility increases confidence in the results. However, as with most meta-analyses, there was no gold standard of truth, and results must be interpreted judiciously. The generalization of these findings to other meta-analyses, which differ in outcomes, missing data, or between-study heterogeneity, requires further consideration.

question:
Context: To explore the importance of follicle-stimulating hormone receptor (FSHR) in granulosa cells in the ovarian response to gonadotropin stimulation.', 'Prospective study.', "A women's hospital in China.", 'One hundred infertile women undergoing ovarian stimulation with recombinant follicle-stimulating hormone (rFSH).', 'These women were divided into three groups: poor, moderate, and high responders, according to the number of follicles with diameter >/=14 mm. The FSHR expression at both mRNA and protein levels was determined by either reverse transcription-polymerase chain reaction or Western blot in granulosa cells. E(2) concentrations in serum and FSH levels in serum/follicular fluid (FF) were measured by electrochemiluminescence immunoassay.', 'Relative expression of mRNA and protein of FSHR in granulosa cells, serum E(2), FSH level in serum and FF, and the number of mature follicles.', 'The expression of FSHR, at both the mRNA and protein levels, was significantly different among the three groups, with the lowest expression in the poor responders. The level of FSHR protein was positively correlated with the peak level of serum E(2) and the number of mature oocytes. FSH levels in FF and the dosage of rFSH used were significantly different among the three groups, with the highest values in the poor responders.\Question: Is poor ovarian response to gonadotropin stimulation associated with low expression of follicle-stimulating hormone receptor in granulosa cells?
answer:
Different levels of FSHR expression in granulosa cells result in different ovarian response, and lower expression of FSHR may account for poor ovarian response to gonadotropin stimulation, which suggests the critical role of FSHR in the ovarian response to gonadotropin stimulation.