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.

Ex Input:
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.

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

Ex Input:
Accurate evaluation of the biological behavior of Gastrointestinal stromal tumor and careful selection of patients with a high risk for tumor recurrence are necessary. In the present study, we analyzed prognostic factors in patients with GIST.', 'A total of 214 patients who had undergone curative resection of a localized primary gastric GIST without adjuvant therapy were enrolled in this retrospective study. Prognostic factors were analyzed. The growth pattern was classified as intramural, endoluminal, exoluminal, or mixed- type.', 'On univariate and multivariate analyses, recurrence was predicted by exoluminal or mixed-type (hazard ratio [HR]=3.7, p=0.043), tumor size of >3.5 cm (HR=7.1, p=0.01), and mitotic rate of >5/50 high-power fields (HR=7.9, p<0.001).

Ex Output:
Is macroscopic type a prognostic factor for recurrence-free survival after resection of gastric GIST?

Ex Input:
We wanted to determine whether genetic variability in the gene encoding microsomal epoxide hydrolase (EPHX) contributes to individual differences in susceptibility to the occurrence of placental abruption.', 'The study involved 117 women with placental abruption and 115 healthy control pregnant women who were genotyped for two single nucleotide polymorphisms (SNPs), T-->C (Tyr113His) in exon 3 and A-->G (His139Arg) in exon 4, in the EPHX gene. Chi-square analysis was used to assess genotype and allele frequency differences between the women with placental abruption and the control group. In addition, single-point analysis was expanded to pair of loci haplotype analysis to examine the estimated haplotype frequencies of the two SNPs, of unknown phase, among the women with placental abruption and the control group. Estimated haplotype frequencies were assessed using the maximum-likelihood method, employing an expectation-maximization algorithm.', 'Single-point allele and genotype distributions in exons 3 and 4 of the EPHX gene were not statistically different between the groups. However, in the haplotype estimation analysis we observed a significantly decreased frequency of haplotype C-A (His113-His139) among the placental abruption group compared with the control group (P = .007). The odds ratio for placental abruption associated with the low-activity haplotype C-A (His113-His139) was 0.552 (95% confidence interval, 0.358 to 0.851).

Ex Output:
Is low-activity haplotype of the microsomal epoxide hydrolase gene protective against placental abruption?