Given a passage with a context and an answer, 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: Context: Although the presence of perineural invasion has been recognized as a poor prognostic factor in extrahepatic cholangiocarcinoma, the molecular mechanisms of perineural invasion in extrahepatic cholangiocarcinoma remain unclear. Nerve growth factor has been reported to be a candidate predictive biomarker of perineural invasion in some cancers.', 'To investigate the impact of intratumoral nerve growth factor expression in resected extrahepatic cholangiocarcinoma on survival.', 'Intratumoral nerve growth factor expression was investigated immunohistochemically in 112 patients with resected extrahepatic cholangiocarcinoma. Associations between nerve growth factor expression and clinicopathological factors were statistically evaluated, and risk factors for poor survival were analyzed using univariate and multivariate analyses.', 'High and low nerve growth factor expression was observed in 62 (55%) and 50 (45%) patients, respectively. For all 112 patients, no significant correlation was found between nerve growth factor expression and presence of perineural invasion (P = 0.942). Moreover, nerve growth factor expression was not associated with recurrence-free survival (P = 0.861) and overall survival (P = 0.973). In multivariate analysis, lymph node metastasis (P = 0.004) was identified as an independent risk factor for early recurrence and the presence of perineural invasion (P = 0.002) and lymph node metastasis (P < 0.001) was identified as independent risk factors for poor survival.
Answer: Intratumoral nerve growth factor expression is not associated with perineural invasion or recurrence-free and overall survival in patients with resected extrahepatic cholangiocarcinoma.

A: Is nerve Growth Factor Expression Associated with Perineural Invasion in Extrahepatic Cholangiocarcinoma?
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Q: Context: Isotretinoin is effective in the treatment of severe acne and rosacea. Both parent drug and its main metabolite 4-oxo-isotretinoin are potentially teratogenic compounds and contain a carboxylic acid moiety. In the presence of ethanol, naturally occurring as well as synthetic retinoids also containing a carboxylic acid moiety are capable of undergoing an ethyl esterification with the metabolic formation of more lipophilic compounds with a much longer terminal half-life.', 'To determine if isotretinoin (13-cis-RA), its main metabolite 4-oxo-isotretinoin (4-oxo-13-cis-RA), and other possible metabolites in the presence or absence of ethanol are converted to their corresponding ethyl derivatives in patients with severe acne or rosacea after multiple isotretinoin dosing. In addition, pharmacokinetic parameters of the parent drug and its 4-oxo metabolite were determined.', 'Eleven patients with severe acne or rosacea were treated with isotretinoin daily for 3 months and investigated pharmacokinetically during 24 h after 1 month of treatment and for up to 28 days after discontinuation of therapy. A possible influence of ethanol was evaluated using a simple self-administered questionnaire and by measuring serum ethanol levels during treatment. The concentrations of isotretinoin, 4-oxo-isotretinoin and possible ethylated and nonethylated metabolites were measured by reverse-phase high-performance liquid chromatography.', "Although seven of 11 patients had a considerable weekly alcohol intake, no endogenous synthesis of ethyl derivatives of isotretinoin, the main 4-oxo metabolite or the all-trans compounds was chromatographically detectable in any of the patients' plasma samples during the treatment period. Multiple dose pharmacokinetic data for the parent drug and its main metabolite were comparable to previous studies.
Answer: The metabolism and pharmacokinetics of isotretinoin and its main metabolites are not influenced by ethanol during long-term isotretinoin treatment. After ceasing long-term isotretinoin therapy the recommended period of 1 month for using anticonceptive measures in fertile women seems adequate.

A: Are the metabolism and pharmacokinetics of isotretinoin in patients with acne and rosacea influenced by ethanol?
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Q: Context: This study was performed to evaluate the effects of acute systemic inflammation on peritoneal solute transport rate (PSTR) in chronic peritoneal dialysis (CPD) patients.', 'A baseline standard peritoneal equilibration test (PET) was performed on each patient every 6 months, and blood concentration of high-sensitivity C-reactive protein (hs-CRP) was assayed every 2 months in our peritoneal dialysis clinic. Acute systemic inflammation was defined as a greater than 10-fold increase in hs-CRP concentration compared with baseline value, in the absence of peritonitis, and returning to baseline level in 2 months. In patients with acute systemic inflammation, PET and hs-CRP concentration assays were performed during inflammation and after recovery. Ten patients with acute systemic inflammation were enrolled in the inflammation group and 42 other patients served as controls.', 'There were no significant changes in hs-CRP and dialysate-to-plasma ratio of creatinine (D/Pcreat) in the control group during the study period. In the inflammation group, median hs-CRP levels at baseline, during acute inflammation, and at recovery were 2.3 mg/L (range 0.3 - 4.5 mg/L), 39.2 mg/L (range 15.1 - 117.4 mg/L), and 3.7 mg/L (range 0.9 - 8.9 mg/L), respectively. Median D/Pcreat increased significantly from baseline (0.64; range 0.55 - 0.98) to time of acute inflammation (0.72; range 0.60 - 0.96) (p < 0.05). The D/Pcreat at recovery was 0.67 (range 0.52 - 0.94), which decreased significantly from time of acute inflammation (p < 0.05). There was no correlation between changes in log (hs-CRP) and changes in D/Pcreat.
Answer: We have shown here that acute systemic inflammation is associated with a temporary increase in PSTR in CPD patients.

A:
Is acute systemic inflammation associated with an increase in peritoneal solute transport rate in chronic peritoneal dialysis patients?
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