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.
--------
Question: Context: We quantitatively evaluated the collagen-to-smooth muscle tissue matrix ratio in ureteropelvic junction obstruction, and compared the ratio with the degree of obstruction, patient age and postoperative renal recovery.', "We analyzed histological sections from 65 patients with ureteropelvic junction obstruction and 6 normal controls. Morphological and functional grading systems were adapted to determine the degree of renal obstruction. To examine smooth muscle and collagen tissue, sections were stained using Masson's trichrome. Two distinct populations of collagen versus smooth muscle were identified and the tissue matrix ratio was calculated by color image analysis.", 'The mean tissue matrix ratio plus or minus standard deviation was 1.32+/-0.79 in all patients with ureteropelvic junction obstruction but only 0.30+/-0.10 in normal controls (p <0.0001). It appeared that the lower the tissue matrix ratio, the better the improvement in postoperative hydronephrosis (r = -0.50, p = 0.0001). Better recovery of renal function after pyeloplasty was observed with a decrease in the tissue matrix ratio (r = -0.43, p = 0.0004). We divided patients according to the tissue matrix ratio into groups 1--ratio 1 or less, 2--greater than 1 to 1.5 and 3--greater than 1.5 to determine a more detailed and clinically applicable correlation of tissue matrix ratio with postoperative renal functional changes. Better improvement in postoperative renal function was observed in group 1 than in group 3 (p = 0.002). Also, the tissue matrix ratio increased with patient age (r = 0.33, p = 0.007).
Answer: Since our data represent an objective and quantitative parameter associated with ureteropelvic junction obstruction, we believe that our findings may help to predict the prognosis after pyeloplasty.

Answer: Does collagen-to-smooth muscle ratio help prediction of prognosis after pyeloplasty?

Question: Context: To analyze the effect of antiretroviral therapy, including drugs that have good penetration in cerebrospinal fluid (CSF), on neuropsychologic performance.', 'One hundred sixty-five HIV-1-infected patients exposed to a stable highly active antiretroviral therapy (HAART) regimen were studied. Neuropsychologic examinations were performed for all patients.', "A total of 50.3% of patients were impaired. In multivariate analysis, older age (for 10-year increase, odds ratio [OR] = 4.8, 95% confidence interval [CI]: 2.2 to 10.4; P< 0.0001) and higher plasma HIV-1 RNA levels (OR = 1.90, 95% CI: 1.1 to 3.2; P = 0.021) at testing were independently associated with an increased probability of impaired neurocognitive performance, whereas higher educational level was a protective factor (OR = 0.76, 95% CI: 0.65 to 0.90; P=0.001). A significant linear correlation was observed between the neuropsychologic z score for 8 tests (NPZ8) score, a quantitative parameter of neurocognitive impairment, and CD4 cell count at neuropsychologic testing (R = 0.273, P = 0.001) and between the NPZ8 score and the patient's age (R = 0.288, P = 0.001).
Answer: Our study indicates that the use of stable HAART, including multiple drugs that have good CSF penetration, was not associated with neuropsychologic performance. To prevent independent replication of HIV in CSF with better control of a relevant reservoir of HIV is one of the crucial aims of therapeutic strategy.

Answer: Do neuroactive antiretroviral drugs influence neurocognitive performance in less advanced HIV-infected patients responding to highly active antiretroviral therapy?

Question: Context: Surgeon-performed ultrasonography is increasingly becoming part of the initial evaluation of patients after blunt or penetrating trauma. Currently, most institutions obtain a subxyphoid or subcostal view of the heart and pericardial space, and a three-view ultrasonogram of the abdomen to detect blood in the pericardial sac or in three dependent abdominal areas.', 'A left parastemal standard transverse transthoracic view is described in addition to the aforementioned views. This facilitates the visualization of the pericardial sac when a subxyphoid or subcostal view cannot be obtained because of anatomical reasons (narrow subxyphoid space) or local factors (pain, fractures, subcutaneous emphysema, or chest wall contusion).', 'The transthoracic view can be useful in patients where the subxyphoid view is difficult to obtain through the conventional approach. In most patients an excellent view of the pericardial sac and ventricles can be obtained and, therefore, expedites the diagnosis and treatment of patients with hemopericardium.
Answer: Surgeon-performed ultrasonography has become the diagnostic test of choice for patients suspected of having hemopericardium and cardiac tamponade. Transthoracic ultrasonography is an excellent alternative for those patients where a subxyphoid or subcostal view to visualize the pericardial sac and heart cannot be obtained owing to local or anatomical factors.

Answer:
Is transthoracic ultrasonography an alternative to subxyphoid ultrasonography for the diagnosis of hemopericardium in penetrating precordial trauma?