instruction:
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: Parkinsonian signs, especially gait impairment, are common and associated with morbidity and mortality in older persons. Our objective was to test the hypothesis that substantia nigra neurofibrillary tangles (NFTs) are related to parkinsonian signs in older persons with and without dementia.', "We studied 86 deceased older Catholic clergy without idiopathic Parkinson's disease from the Religious Order Study, a longitudinal clinical-pathological study. Mean age at death was 85.3 years. Signs of gait disturbance, bradykinesia, rigidity, and tremor were assessed proximate to death using a modified Unified Parkinson's Disease Rating Scale. Forty-micrometer paraffin-embedded sections of substantia nigra were bleached before tau immunohistochemistry and the optical disector was used to count NFTs. We used multivariable linear regression to examine parkinsonian signs as a function of nigra NFTs, controlling for age, sex, education, and cortical NFTs.", 'Substantia nigra NFTs were present in 67 of 86 persons (77.9%). After controlling for age, sex, education, and cortical NFTs, nigra NFTs were related to gait impairment (p < 0.001), but not bradykinesia, rigidity, or tremor. Results were not confounded by dementia, Braak score, neuroleptic medication, cerebral infarcts, or Lewy bodies.
Answer: NFTs in the substantia nigra are associated with gait impairment in older persons with and without dementia.
answer:
Are substantia nigra tangles related to gait impairment in older persons?

question:
Context: Cross-sectional, clinical measurement.', 'To investigate the validity of the Duruoz Hand Index (DHI) in the assessment of hand function in patients with tetraplegia.', "A total of 40 patients with tetraplegia participated. Patients' upper extremities were assessed on the level of 'body function and structure' [The American Spinal Cord Injury Association (ASIA) Impairment Scale (AIS) 2000 revised criteria, upper extremity motor score (UEMS), neurologic level of injury and visual analogue scale of hand function (VAS-HF)], 'activity' [DHI and Quadriplegia index of function-short form (QIF-SF)] and 'body function and structure, activity and participation' [Health Survey Short Form-36 (SF-36)] according to International Classification of Function.", 'The DHI showed significant correlations with UEMS, AIS, QIF-SF, VAS-HF, physical functioning and physical compound summary scores of SF-36.
Answer: The DHI was found a valid method in the assessment of hand functions in patients with tetraplegia.
answer:
Do validation of Duruoz Hand Index in patients with tetraplegia?

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Context: To evaluate the cytotoxic and apoptotic effects of bishydroxycoumarin (BHC) against human glioma cells and to study their mode of action.', 'Three cells were used in the experiments. MTT and LDH assays were used to assess the cytotoxic effects of BHC while an in vitro wound healing assay was used to study the effect of BHC on cell migration. Fluorescence microscopy and annexin V-FITC assay were used to study the cellular morphology and apoptotic effects while flow cytometry in combination with propidium iodide (PI) were used to study cell cycle arrest induced by BHC.', 'BHC induced substantial and dose-dependent cytotoxic effects against all three cell lines with U87MG cell line being most susceptible. BHC also inhibited cell migration and induced characteristic morphological changes including chromatin condensation, nuclear shrinkage which increased with increasing dose of BHC. The apoptotic cell population (both early and late apoptotic cells) increased with increasing dose of BHC which also induced substantial G0/G1 cell cycle growth arrest in U87MG cells.
Answer: This study provides help to elucidate the translational potential of the in vitro results to be used for further in vivo studies on human glioma using animal or human subjects. The mechanistic pathway studied in this report could be helpful in explaining the mode of action of these classes of natural products.
answer:
Are anticancer effects of bishydroxycoumarin mediated through apoptosis induction , cell migration inhibition and cell cycle arrest in human glioma cells?