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.
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Question: Prostasomes are small (40-500 nm), granule-like bodies, found in normal epithelial cells of the prostate and secreted into the prostate duct system. Also poorly differentiated prostate cancer cells are producing prostasomes, since we could isolate and purify prostasomes from vertebral metastases with biochemical methods. To find out whether these prostasomes are secreted into extracellular sites of the metastases, we used electron microscopy.', 'Small biopsies from vertebral metastases of prostate cancer, taken directly from the operating field at surgery, were immediately fixated, embedded in plastic and processed for electron microscopy.', 'We found that prostasomes could be identified extracellularly in the interstitial tissues as well as in the cytoplasm of the metastatic cells.

Answer: Are prostasomes secreted from poorly differentiated cells of prostate cancer metastases?

Question: We investigated the clinical significance of GALNT4 expression in patients with clear cell renal cell carcinoma.', 'Enrolled in this study were 104 patients treated with curative nephrectomy at Zhongshan Hospital, Shanghai during 2004. Of the cohort 23 patients died of disease, 33 experienced recurrence and 3 died of another cause. GALNT4 density was assessed by immunohistochemistry in patient specimens. Univariate and multivariate Cox models, and ROC analysis were used to analyze the impact of prognostic factors on overall and relapse-free survival. Kaplan-Meier analysis with the log rank test was done to compare clinical outcomes between subgroups.', 'Intratumor GALNT4 expression was significantly lower than peritumor expression. Low GALNT4 expression was associated with poor overall and relapse-free survival (p = 0.001 and 0.004, respectively). Intratumor GALNT4 expression, which negatively correlated with tumor size (p = 0.032), necrosis (p=0.013) and TNM stage (p = 0.017), was an independent prognostic indicator for overall and relapse-free survival (HR 3.088, p = 0.020 and 2.173, p = 0.047, respectively). Extending the TNM staging system according to GALNT4 expression showed a better prognostic value for overall and relapse-free survival (AUC 0.786, p = 0.029 and 0.761, p = 0.040, respectively).

Answer: Does gALNT4 predict clinical outcome in patients with clear cell renal cell carcinoma?

Question: The aim of this study was to investigate whether microelectronic wear-time documentation can contribute to individualized orthodontic management.', 'The wear times and behaviors of 281 patients undergoing orthodontic treatment with removable appliances were quantified and analyzed using the TheraMon microelectronic system (Sales Agency Gschladt, Hargelsberg, Austria) over a 6-month treatment period.', 'The 281 study participants wore their removable appliances for a median of 9.0 hours per day, compared with the 12 to 15 hours per day prescribed. Wear behavior was variable and heterogeneous in patients with almost identical median wear times, with fluctuating and numerous zero wear-time periods observed.

Answer:
Does microelectronic wear-time documentation of removable orthodontic devices detect heterogeneous wear behavior and individualizes treatment planning?