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.

Q: The purpose of this study is to determine whether chiropractic manipulation is associated with any measurable changes in the difference between the arterial blood pressures on the left and right before and after treatment in normotensive subjects.', 'A nonrandomized, matched pair, controlled clinical trial, with the treatment (manipulation) group and control (resting) group matched for age and sex, was performed in chiropractic student clinics in London, UK. The treatment group consisted of 35 new patients presenting to a single student chiropractor between the start of April 2003 and the end of August 2003. The control group consisted of 35 nonpatients matched for sex and age. The intervention was chiropractic manipulation. Preintervention and postintervention systolic and diastolic blood pressures were recorded in both arms through the use of a digital oscillometric sphygmomanometer.', "A significant difference was found between the pre- and posttreatment blood pressure differences for systolic pressures (P = .01), but no significant difference was found in either set of control data or the treatment diastolic values. A significant difference was also found between the treatment and control group's preintervention systolic differences (P = .002), but not between the groups at any other time.

A: Does chiropractic manipulation affect the difference between arterial systolic blood pressures on the left and right in normotensive subjects?
****
Q: To determine whether the number and location of positive surgical margins (PSMs) in radical prostatectomy (RP) surgical specimens affect biochemical recurrence (BCR) rates.', 'The locations of PSMs were recorded for 1308 consecutive men who underwent RP between October 2000 and December 2006. BCR was defined as three consecutive prostate-specific antigen (PSA) level rises with the peak level >or=0.15 ng/mL. Multivariate regression analyses were used to identify preoperative predictors of PSMs and BCR. The estimated 5-year risk of BCR was calculated using the Kaplan-Meier method.', 'In all, 128 (9.8%) men had one or more PSMs. The mean body mass index, mean preoperative serum PSA level, the distributions of clinical stage and biopsy Gleason scores, and the presence or absence of biopsy perineural invasion were significantly different between men with or with no PSMs. In multivariate analysis, baseline serum PSA level, Gleason score and perineural invasion were independent preoperative predictors of PSMs. The 5-year actuarial BCR rates were dependent on the site of the PSM (P = 0.035) and not the number of PSMs (P = 0.18). The rank order of estimated 5-year BCR rates according to the site of PSMs were base > anterior > posterolateral > apex approximately posterior.

A: Does site of positive surgical margins influence biochemical recurrence after radical prostatectomy?
****
Q: To find the relationship between rtPA treatment vs. MMP-9 activity, MMP-3, and TIMP-1 serum levels related to patients' neurological status during acute ischaemic stroke (IS).", '35 IS patients were enrolled. 14 of them underwent thrombolytic therapy with Actylise (rtPA group). The serum samples were obtained at 3 time-points for rtPA group (time-point 0: 1st-4th hour of stroke; time-point 1 - immediately after rtPA administration; time-point 2 - on day 5-7 from stroke onset). Remaining patients had venous blood collection at two time-points: time-point 1 - 5th-10th hour of stroke and time-point 2 - on day 5-7 of stroke. MMP-9 was analyzed with gelatin zymography, MMP-3 and TIMP-1 serum levels were analyzed with ELISA method. NIHSS improvement ratio (IR) was calculated as a difference between NIHSS score at the admission and discharge of patient.', 'The active form of MMP-9 (86kDa) was not observed in any analyzed samples. Total MMP-9 activity was significantly elevated at time-point 1 in rtPA group in comparison with non-rtPA group. MMP-3 serum level significantly decreased during rtPA administration in comparison with non-rtPA group and it was restored at time-point 2. MMP-3 negatively correlated with IR values (p=0.06).

A:
Does the rtPA increase MMP-9 activity in serum during ischaemic stroke?
****