instruction:
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.
question:
Thyroid-stimulating hormone (TSH) levels within populations do not follow Gaussian distribution, and normal limits are derived after mathematical normalization. The clinical relevance of these limits is unknown. The objective of this study was to compare upper and lower TSH limits by four data normalization methods with non-normalized data and assess their clinical relevance.', 'Results of blood samples taken by community physicians and stored in a computerized database were analysed after removing samples from patients with evidence of thyroid illness. TSH values were normalized by the Hoffmann and Tukey methods and each method with natural log transformation. Non-normalized data for TSH in the uppermost and lowermost percentile were also calculated. Clinical relevance was determined by alterations in thyroid hormone levels at, below and above the limits for each method.', 'The maximal reduction from non-normalized data for the upper normal limit (UNL) was by the Hoffman method 43% = 31 mIU/l). The maximal increase for the lower normal limit (LNL) was also by the Hoffman method (708% = 081 mIU/l). There was very limited difference in average FT3 and FT4 between patients with TSH within, below or above the normal range for all methods.
answer:
Do normal limits for serum thyrotropin vary greatly depending on method?

question:
Episodic memory enables us to consciously recollect personally experienced past events. Memory performance is reduced in patients with mild cognitive impairment (MCI), an at-risk condition for Alzheimer's disease (AD).", 'We used functional MRI (fMRI) to compare brain activity during memory encoding in 29 healthy elderly subjects (mean age 67.7 (SD 5.4) years) and 21 patients with MCI (mean age 69.7 (SD 7.0) years). Subjects remembered a list of words while fMRI data were acquired. Later, they had to recognise these words among a list of distractor words. The use of an event related paradigm made it possible to selectively analyse successfully encoded items in each individual. We compared activation for successfully encoded words between healthy elderly subjects and patients with MCI.', 'The main intergroup difference was found in the left hippocampus and surrounding medial temporal lobe (MTL) regions for the patients with MCI compared with healthy subjects during successful encoding.
answer:
Is hippocampal activation in patients with mild cognitive impairment necessary for successful memory encoding?

question:
Flow cytometry (FACS) is a common technique in blood banking. It is used, for example, for the enumeration of residual white blood cells in plasma and in cellular blood products. It was investigated whether it can also be applied for sterility testing of buffy coat-derived platelet concentrates (PCs).', 'Plasma-reduced PCs were spiked with bacteria and stored at 20 to 24 or 37 degrees C for various times. The following 10 species were used: Bacillus cereus, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Propionibacterium acnes, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens, and Yersinia enterocolitica. Bacterial DNA was stained with thiazole orange. After the platelets were lysed, bacteria were enumerated by FACS.', 'All bacteria species used were detectable by FACS. The lower detection limit was approximately 100 bacteria per microL, that is, 10(5) per mL. In general, the titers measured were 1.2- to 3-fold higher than those determined by colony forming assay. In one case (K. pneumoniae) in which the dot plot of the bacteria cloud overlapped with that of bacteria debris, they were consistently lower. When PC samples were inoculated with approximately 1 colony-forming unit per mL of bacteria and kept at 37 degrees C, most species were detected within 21 hours or less. Exceptions were E. cloacae and P. acnes, which were detected after 24 to 40 and 64 hours, respectively. At 20 to 24 degrees C, the detection times were strongly prolonged.
answer:
Does basics of flow cytometry-based sterility testing of platelet concentrate?