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: Restoration of posterior condylar offset during TKA is believed to be important to improving knee kinematics, maximizing ROM, and minimizing flexion instability. However, controversy exists regarding whether there are important anatomic differences between sexes and whether a unisex knee prosthesis can restore the anatomy of knees in males and females.', 'The purposes of our study were to determine if sex differences exist in (1) absolute posterior condylar offset size, (2) relative posterior condylar offset size in relation to total condylar height, and (3) posterior condylar articular cartilage thickness.', 'We identified 100 patients (50 men and 50 women) without a history of arthritis, deformity, dysplasia, osteochondral defect, fracture, or surgery about the knee who had MRI of the knee performed. All MR images were ordered by primary care medical physicians for evaluation of nonspecific knee pain. Using a previously described three-dimensional MRI protocol, we measured posterior condylar offset, total condylar height, and articular cartilage thickness at the medial and lateral femoral condyles and compared values to evaluate for potential sex differences. We performed an a priori power calculation using a 2-mm posterior condylar offset difference as the minimum clinically important difference; with 2n = 100, our power to detect such a difference was 99.8%.', 'Compared with females, males had greater medial posterior condylar offset (30 mm [95% CI, 29.3-30.7 mm; SD, 2.5 mm] vs 28 mm [95% CI, 27.0-28.5 mm; SD, 2.7 mm]), lateral posterior condylar offset (27 mm [95% CI, 26.2-27.3 mm; SD, 2.0 mm] vs 25 mm [95% CI, 24.2-25.4 mm; SD, 2.0 mm]), medial condylar height (63 mm [SD, 3.2 mm] vs 57 mm [SD, 4.4 mm]), and lateral condylar height (71 mm [SD, 5.2 mm] vs 65 mm [SD: 4.0 mm]) (all p values < 0.001). However, the mean ratio of medial posterior condylar offset to medial condylar height (0.48 [SD, 0.04] vs 0.49 [SD, 0.05]) and the mean ratio of lateral posterior condylar offset to lateral condylar height (0.38 [SD, 0.05] vs 0.38 [SD, 0.03]) were not different between sexes (p = 0.08 and p = 0.8, respectively). There also was no sex difference in mean articular cartilage thickness at either condyle (medial condyle: 2.7 mm [SD, 0.5 mm] vs 2.5 mm [SD, 0.7 mm]; lateral condyle: 2.6 mm [SD, 0.6 mm] vs 2.5 mm [SD, 0.8 mm]) (both p values 0.1).

Answer: Do no sex differences exist in posterior condylar offsets of the knee?

Question: Annual seasonal and pandemic influenza vaccines need to be produced in a very tight time frame. Haemagglutinin (HA) is the major immunogenic component of influenza vaccines, and there is a lot of interest in improving candidate vaccine viruses.', "It has been shown elsewhere that mutations introduced in the non-coding region of influenza genome segments can upregulate protein expression. Our objective was to assess a virus based on the laboratory strain A/PR/8/34 (PR8) containing a modified 3' non-coding region of RNA segment 4 (haemagglutinin).", 'NIBRG-93 was generated using reverse genetics. HA protein expression and growth properties were assessed. The virus phenotype suggested that it could be a candidate for use as a live attenuated vaccine, so in vivo studies were performed to assess its suitability.', "NIBRG-93 virus has enhanced haemagglutinin production and is significantly attenuated. Electron microscopy (EM) shows that the modified virus produces a large proportion of 'virus-like particles' that consist of budded cell membrane covered in HA but lacking M1 protein. The virus was shown to be attenuated in mice and offered complete protection against lethal challenge.

Answer: Does a promoter mutation in the haemagglutinin segment of influenza A virus generate an effective candidate live attenuated vaccine?

Question: There is no consensus about the ideal method for diagnosis in patients who have already undergone endoscopic ultrasound fine needle aspiration (EUS-FNA), and the inconclusive material is often obtained. The aim was to evaluate the diagnostic yield of the second EUS-FNA of pancreatic lesions.', 'A retrospective analysis of prospectively collected data of patients with EUS-FNA of pancreatic lesions is performed. All patients who underwent more than one EUS-FNA for the evaluation of suspected pancreatic cancer over a 7-year period were included in the analysis.', 'A total of 296 EUS-FNAs of the pancreas were performed in 257 patients. The diagnostic yield with the first EUS-FNA was 78.6% (202/257). Thirty-nine (13.3%) FNAs were repeated in 34 patients; 17 (50%) patients were women. The mean standard deviation (SD) age was 58.8 16.1 years. The location of the lesions in the pancreatic gland, from which the second biopsies were taken, was head of the pancreas, n = 28 (82.4%), body of the pancreas, n = 3 (8.8%), and tail, n = 3 (8.8%). The mean SD of the size of the lesion was 36.3 14.6 mm. The second EUS-FNA was more likely to be positive for diagnosis in patients with an "atypical" histological result in the first EUS-FNA (odds ratio [OR]: 4.04; 95% confidence interval [CI]: 0.9-18.3), in contrast to patients with a first EUS-FNA reported as "normal" (OR: 0.21; 95% CI: 0.06-0.71). Overall, the diagnostic yield of the second EUS-FNA was 58.8% (20/34) with an increase to 86.3% overall (222/257).

Answer:
Is repeat endoscopic ultrasound fine needle aspiration after a first negative procedure useful in pancreatic lesions?