instruction:
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.
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Context: Pulmonary vein (PV) isolation is a curative treatment for patients with atrial fibrillation. The aim of this study was to evaluate prospectively the effects of adenosine administration on the PV activity and atrio-venous conduction after PV isolation.', 'Twenty-nine patients (21 m; age: 55+/-8 years) were submitted to ostial PV isolation guided by basket catheter recordings. After successful isolation, the effects of a 12 mg intravenous bolus of adenosine were tested in 62 PVs. In 22/62 PVs (35%), left atrium (LA)-to-PV conduction was transiently (16.6+/-7.1 s, range: 3.8-27.9 s) or permanently (3 PVs) restored in response to adenosine administration. The prevalence of this phenomenon was 39% in left superior PVs, 43% in right superior PVs, and 22% in left inferior PVs (p=0.365). It occurred more frequently in the presence of dissociated PV activity (11/15 PVs, 73% vs. 11/47 PVs, 23%; p=0.002), whereas it was not influenced by the median duration of the radiofrequency current (RFC) delivery for each PV [19 (IQR: 12-26) min vs. 16 (IQR: 11-24) min: p=0.636]. A lengthening or shortening of the LA-PV conduction time was observed at LA-PV conduction appearance and disappearance in 36% and 55% of the cases, respectively. Further RFC applications (median: 5.5 min, IQR: 4-11 min) at the residual conduction breakthrough(s) indicated by the basket catheter recordings definitively eliminated adenosine-induced recovery of LA-PV conduction in all cases. Finally, when present, intrinsic PV discharge was invariably depressed by adenosine administration.
Answer: Adenosine may transiently or permanently re-establish LA-PV conduction after apparently successful PV isolation. This phenomenon is abolished by additional RFC delivery. However, its possible influence on the clinical results of PV ablation must be evaluated by properly designed, randomized studies.
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Does adenosine restore atrio-venous conduction after apparently successful ostial isolation of the pulmonary veins?

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Context: Absenteeism from outpatient appointments is common. Telephone appointment-reminder calls reduce outpatient-appointment absenteeism in many clinic settings.', 'To determine if telephone appointment-reminder calls reduce outpatient absenteeism at a hospital-based pulmonary function laboratory.', 'We conducted a retrospective review of our pulmonary function laboratory's outpatient appointment records from April to November 2004. Data were collected from consecutive outpatient appointments, including patient age, sex, whether a telephone appointment-reminder call was successfully made, and whether the patient showed up for the scheduled test. We performed 3 analyses. Differences in absenteeism between the groups was the primary outcome measure. First, appointments were separated into 2 groups: (1) appointments for which a reminder call was attempted ("called" group) and (2) appointments for which a reminder call was not attempted ("not-called" group). The appointments were then separated into 2 further groups: (1) the reminder call was successfully achieved ("contacted" group) and (2) the patient either was not called or was called but could not be reached ("not-contacted" group). Finally, the contacted group was separated into 2 further groups: (1) reminder calls that resulted in direct conversation with an appropriate person at the patient's listed telephone number, and (2) reminder message left on an answering machine.', 'Data were collected from 515 consecutive outpatient appointments; 45 (8.7%) of these patients did not show up for testing. The absentee rate was 4.7% (n = 10) in the called group and 11.6% (n = 35) in the not-called group (p = 0.0066). In the called group, 6.5% (n = 14) could not be reached. The absentee rate was 4% (n = 8) in the contacted group and 11.7% (n = 37) in the not-contacted group (p = 0.0021). We found no difference in absenteeism between patients who received reminders via direct conversation (4.2%) and those who had a reminder message left on an answering machine (3.7%) (p > 0.05).
Answer: A policy of reminding outpatients of their appointments via telephone reduces absenteeism at a hospital-based pulmonary function laboratory. We found no difference in absenteeism between communicating the reminder via direct conversation versus via leaving a message on an answering machine.
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Does the effect of telephone appointment-reminder call on outpatient absenteeism in a pulmonary function laboratory?

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Context: A previous study by the authors has shown that recombinant myocilin purified from a prokaryotic expression system increases outflow resistance in cultured human anterior segments. The present study was performed to determine whether full-length myocilin purified from a human trabecular meshwork cell expression system alters outflow resistance after infusion into human anterior segments.', "A feline immunodeficiency virus vector encoding both full-length myocilin (amino acids 1-503 fused to C-terminal V5 and six-histidine epitopes) and puromycin resistance was used to transduce a transformed trabecular meshwork cell line (TM5). Stably expressing cells were selected with puromycin. Recombinant myocilin was purified from the media using nickel ion affinity chromatography. Control purifications were performed on media from parental TM5 cells. Anterior segments of human eyes were placed in organ culture and perfused with either Dulbecco's modified Eagle's medium (DMEM) or DMEM supplemented with 50% porcine aqueous humor. One eye received an anterior chamber exchange with recombinant myocilin (2 microg/mL), whereas the fellow eye received an equal volume of control. Immunohistochemistry was performed with anti-myocilin and anti-V5 antibodies. Native polyacrylamide gel electrophoresis was used to analyze myocilin complex formation in porcine aqueous humor.", 'Recombinant myocilin in porcine aqueous humor increased outflow resistance in cultured human anterior segments (91% +/- 68% [mean +/- SD] versus 18% +/- 31% in fellow control eye; n = 9, P = 0.004). Maximum outflow resistance was obtained 5 to 17 hours after infusion and remained above baseline for >3 days. Recombinant myocilin also increased outflow resistance in eyes incubated in DMEM, but only if myocilin was preincubated with porcine aqueous humor (78% +/- 77% when preincubated in DMEM containing porcine aqueous humor versus 13% +/- 15% when preincubated with DMEM alone, n = 6, P = 0.03). Recombinant myocilin appears to form a complex in porcine aqueous humor with a heat-labile protein(s). Immunohistochemistry revealed the presence of myocilin in the juxtacanalicular region of the trabecular meshwork.
Answer: Myocilin purified from human trabecular meshwork cells increased outflow resistance in cultured human anterior segments, but only after incubation with porcine aqueous humor. Recombinant myocilin appears to form a complex in porcine aqueous humor that enables it to bind specifically within the trabecular meshwork.
answer:
Does perfusion of his-tagged eukaryotic myocilin increase outflow resistance in human anterior segments in the presence of aqueous humor?