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.

[EX Q]: The clinical significance of the hepatitis B virus core-related antigen (HBcrAg) assay in monitoring the antiviral effects of lamivudine is reviewed.', 'The HBcrAg assay simultaneously measured serum levels of hepatitis B core (HBc) and e (HBe) antigens using monoclonal antibodies which recognize common epitopes of these two denatured antigens.', 'Although serum HBcrAg levels correlated linearly with those of hepatitis B virus (HBV) DNA in natural course, the decrease in HBcrAg was significantly slower than in HBV DNA after initiation of lamivudine administration. We analyzed the clinical significance of HBV DNA and HBcrAg levels to predict the occurrence of lamivudine resistance. HBV DNA measurement may be useful to identify patients who are at high risk of developing lamivudine resistance, and HBcrAg measurement may help to detect patients who are at low risk of drug resistance. The measurement of HBcrAg was also found to be a useful prognosticator for reactivation of hepatitis after cessation of lamivudine administration.
[EX A]: Is hepatitis B core-related antigen assay useful for monitoring the antiviral effects of nucleoside analogue therapy?

[EX Q]: Motor dysfunction in complex regional pain syndrome (CRPS) is often considered a functional movement disorder. Earlier studies in patients with functional movement disorders found evidence of cortical inhibition during explicit but not implicit motor tasks, suggesting active inhibition from other brain areas. In this study, we explored whether active inhibition occurs in CRPS patients. We compared patients with CRPS with 2 control groups: healthy controls matched for age and sex, and patients whose hand was immobilized to treat a scaphoid fracture. We used transcranial magnetic stimulation to measure corticospinal excitability at rest and during motor imagery (explicit motor task) and motor observation (implicit motor task). Motor corticospinal excitation measured at rest and during implicit and explicit motor tasks was similar for CRPS patients and healthy controls. Patients with an immobilized hand showed an absence of motor cortical excitation of the corresponding hemisphere during motor imagery of tasks involving the immobilized hand, but not during motor observation. The normal motor cortical processing during motor imagery and motor observation found in the corresponding hemisphere of CPRS patients suggests that the nature of motor dysfunction in this condition differs from that described in literature for patients with functional paresis or under circumstances of limb immobilization.
[EX A]: Is motor cortical activity during motor tasks normal in patients with complex regional pain syndrome?

[EX Q]: The interval between neoadjuvant chemoradiation treatment and surgery has been described as an important predictor of pathologic response to therapy in nonesophageal cancer sites. We retrospectively reviewed our experience with patients who underwent neoadjuvant chemoradiation and esophagectomy to better understand the impact of the timing of surgery on pathologic complete response rates in esophageal cancer.', 'Two hundred thirty-one sequentially treated patients from 2000 to 2011 were identified for this study; 88 of these patients completed neoadjuvant chemoradiation followed by esophagectomy at our institution. The interval between completion of chemoradiation and surgery was calculated for each patient. The patients were categorized into quartiles and also into 3-week interval groups. Treatment factors and surgical morbidity data, including the estimated blood loss and length of operative stay, were also assessed.', 'Quartiles for the neoadjuvant chemoradiation to surgery interval were less than 45 days, 46 to 50 days, 51 to 63 days, and 64+ days. Corresponding pathologic complete response rates were 12.5%, 20.0%, 22.7%, and 40.9% (p = 0.03). Results for 3-week intervals were similar (p = 0.02). There was no association between increasing time interval between the ending of neoadjuvant chemoradiation to surgery and length of stay longer than 2 weeks.
[EX A]:
Is increased time from neoadjuvant chemoradiation to surgery associated with higher pathologic complete response rates in esophageal cancer?