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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Question: Context: Before desflurane is advocated for patients undergoing neurosurgical procedures, it is necessary to determine the effect of desflurane on cerebral blood flow (CBF). In this study, CBF values are compared between desflurane and isoflurane at two doses. In addition, CBF reactivity to CO2 and the effect of prolonged exposure were compared between the two agents.', 'Cerebral blood flow measurements with intravenous 133Xe were performed in 24 patients undergoing craniotomy for mass lesions, randomized to receive either isoflurane or desflurane in oxygen and air. Cerebral blood flow was determined at 1 and 1.5 MAC concentrations at PaCO2 of 25 mmHg in the absence of surgical stimulation. Intraoperatively, with 1.25 MAC anesthesia, CBF was determined at target PaCO2 of 25 and 35 mmHg. In 15 patients, an additional measurement at 1.25 MAC was made before closure.', 'At 1.0 MAC, mean +/- SD CBF values for the desflurane and isoflurane groups were 18 +/- 2 and 20 +/- 3 ml x 100 g-1 x min-1, respectively. At 1.5 MAC, CBF values were the same for the two anesthetics; 17 +/- 3 ml x 100 g-1 x min-1 for isoflurane and 19 +/- 4 ml.100 g-1 x min-1 for desflurane. During 1.25 MAC anesthesia, there were no differences between groups, with CO2 reactivity 1.3 +/- 1.2 ml x 100 g-1 x min-1 x mmHg-1 for desflurane and 1.6 +/- 0.6 ml.100 g-1 x min-1 x mmHg-1 for isoflurane. There was no demonstrable decrease in CBF with prolonged exposure to either agent.
Answer: Desflurane and isoflurane are similar in terms of absolute CBF, the response to increasing doses, and the preservation of CO2 reactivity.

Answer: Do desflurane and isoflurane have similar effects on cerebral blood flow in patients with intracranial mass lesions?


Question: Context: Photodynamic therapy (PDT) is linked with oxidative damage of biomolecules causing significant impairment of essential cellular functions that lead to cell death. It is the reason why photodynamic therapy has found application in treatment of different oncological, cardiovascular, skin and eye diseases. Efficacy of PDT depends on combined action of three components; sensitizer, light and oxygen. In the present study, we examined whether higher partial pressure of oxygen increases lethality in HeLa cell lines exposed to light in the presence of chloraluminium phthalocyanine disulfonate (ClAlPcS2).', 'ClAlPcS2- sensitized HeLa cells incubated under different oxygen conditions were exposed to PDT. Production of singlet oxygen ((1)O2) and other forms of reactive oxygen species (ROS) as well as changes in mitochondrial membrane potential were determined by appropriately sensitive fluorescence probes. The effect of PDT on HeLa cell viability under different oxygen conditions was quantified using the standard methylthiazol tetrazolium (MTT) test.', 'At the highest oxygen concentration of 28 ± 2 mg/l HeLa cells were significantly more sensitive to light-activated ClAlPcS2 (EC50=0.29 ± 0.05 μM) in comparison to cells incubated at lower oxygen concentrations of 8 ± 0.5 and 0.5 ± 0.1 mg/l, where the half maximal effective concentration was 0.42 ± 0.06 μM and 0.94 ± 0.14 μM, respectively. Moreover, we found that the higher presence of oxygen is accompanied with higher production of singlet oxygen, a higher rate of type II photodynamic reactions, and a significant drop in the mitochondrial membrane potential.
Answer: These results demonstrate that the photodynamic effect in cervical cancer cells utilizing ClAlPcS2 significantly depends on oxygen level.

Answer: Does high oxygen partial pressure increase photodynamic effect on HeLa cell lines in the presence of chloraluminium phthalocyanine?


Question: Context: The aim of the study is to investigate whether body mass index (BMI) affected pathological characteristics and biochemical recurrence (BCR) of prostate cancer after radical prostatectomy in Chinese men.', 'Medical records of 211 Chinese patients who underwent radical prostatectomy between 2006 and 2014 were retrospectively reviewed, with follow-up time of 24.5\u2009±\u200927.0\xa0months. Multivariate logistic and Cox regression analyses were applied to address the impact of BMI on adverse pathological outcomes and BCR following prostatectomy. A meta-analysis of published studies from MEDLINE or EMBASE was conducted to determine the relationship between BMI and BCR following prostatectomy among Asian populations.', 'Higher BMI was positively correlated with higher biopsy Gleason score (odds ratios (OR) 1.163, 95\xa0% confidence interval (CI) 1.023-1.322, P\u2009=\u20090.021) and pathological Gleason score (OR 1.220, 95\xa0% CI 1.056-1.410, P\u2009=\u20090.007) in multivariate analysis. BCR was detected in 48 patients (22.7\xa0%). Multivariate Cox proportional hazards analysis revealed that higher BMI (hazard ratio (HR) 1.145, 95\xa0% CI 1.029-1.273, P\u2009=\u20090.013) and prostate-specific antigen (HR 1.659, 95\xa0% CI 1.102-2.497, P\u2009=\u20090.015) levels were independent predictors of BCR. The meta-analysis enrolled eight Asian studies of 4145 patients treated by radical prostatectomy. Based on random-effects approach, a 5\xa0kg/m(2) increase in BMI was correlated with 28\xa0% higher risk of BCR (HR 1.22, 95\xa0% CI 0.86-1.72) without statistical significance.
Answer: The present study suggested that higher BMI was an independent risk factor for a higher Gleason score, as well as an independent predictor of BCR after radical prostatectomy in Chinese patients. Meta-analysis of Asian studies also indicated that obese patients, although without statistical significance, might be more likely to suffer from BCR.

Answer:
Is body mass index associated with higher Gleason score and biochemical recurrence risk following radical prostatectomy in Chinese men : a retrospective cohort study and meta-analysis?