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.

Example Input: Context: This study evaluated two surgical procedures, total splenectomy and spleen-preserving surgery, for the treatment of spleen cystic echinococcosis (CE).', 'A total of 21 patients who underwent surgery for removal of spleen CE were evaluated retrospectively. Patients were divided into two groups, those who received a total splenectomy (n=7) and those who underwent spleen-preserving surgery (n=14).', 'Total splenectomy surgery took 127.1±11.1min and spleen-preserving surgery took 104.3±25.3min (p<0.05). The length of hospital stay was the same for both patient groups (10.6 days on average). No patient suffered from recurrence during follow-up and all of the patients made a good recovery. No patient developed post-splenectomy sepsis or serious infectious complications. No patient suffered recurrence.
Answer: The spleen-saving approach is likely an effective method for the removal of CE spleen cysts given that it is a quick procedure and preserves the function of the spleen. Total splenectomy procedures may be performed particularly for larger, centrally located cysts.
Example Output: Is spleen-preserving surgery effective for the treatment of spleen cystic echinococcosis?

Example Input: Context: To test whether subsensory vibratory noise applied to the sole of the foot using a novel piezoelectric vibratory insole can significantly improve sensation, enhance balance, and reduce gait variability in elderly people, as well as to determine the optimal level of vibratory noise and whether the therapeutic effect would endure and the user's sensory threshold would remain constant during the course of a day.", 'A randomized, single-blind, crossover study of 3 subsensory noise stimulation levels on 3 days.', 'Balance and gait laboratory.', 'Healthy community-dwelling elderly volunteers (N=12; age, 65-90y) who could feel the maximum insole vibration.', 'A urethane foam insole with the piezoelectric actuators delivering subsensory vibratory noise stimulation to the soles of the feet.', 'Balance, gait, and timed Up and Go (TUG) test.', 'The vibratory insoles significantly improved performance on the TUG test, reduced the area of postural sway, and reduced the temporal variability of walking at both 70% and 85% of the sensory threshold and during the course of a day. Vibratory sensation thresholds remained relatively stable within and across study days.
Answer: This study provides proof of concept that the application of the principle of stochastic resonance to the foot sole sensory system using a new low-voltage piezoelectric technology can improve measures of balance and gait that are associated with falls. Effective vibratory noise amplitudes range from 70% to 85% of the sensory threshold and can be set once daily.
Example Output: Does a shoe insole delivering subsensory vibratory noise improve balance and gait in healthy elderly people?

Example Input: Context: Hydrogen sulfide (H2S) is a well-known cytotoxic gas. Recently it has been shown to protect neurons against oxidative stress caused by glutamate, hypochlorous acid (HOCl), and beta-amyloid. The aim of the present study is to explore the cytoprotection of H2S against 1-methyl-4-phenylpyridinium ion (MPP(+))-induced apoptosis and the molecular mechanisms underlying in PC12 cells, a rat cell line derived from pheochromocytoma cells.', 'Cell viability was determined by the conventional 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay. Apoptosis was assessed by Hoechst 33258 nuclear staining and flow cytometric (FCM) analysis after propidium iodide staining. The mitochondrial membrane potential (MMP) was measured by rhodamine 123 (Rh123) probe and reactive oxygen species (ROS) were measured by dihydrorhodamine probe using FCM analysis.', 'MPP(+) reduced the cell viability and induced apoptosis of PC12 cells along with dissipation of MMP as well as overproduction of ROS. Sodium hydrosulfide (NaHS), a H2S donor, protected PC12 cells against MPP(+)-induced cytotoxicity and apoptosis not only by reducing the loss of MMP, but also by attenuating an increase in intracellular ROS.
Answer: H2S significantly protected PC12 cells against cytotoxicity and apoptosis induced by MPP(+), which was associated with the inhibition by H(2)S of MPP(+)-induced dissipation of MMP and overproduction of ROS. These findings can significantly advance therapeutic approaches to the neurodegenerative diseases which are associated with oxidative stress, such as Parkinson's disease.
Example Output:
Does hydrogen sulfide inhibit MPP ( + ) -induced apoptosis in PC12 cells?