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find Keyword "Principal component analysis" 2 results
  • Experimental Study of Colonic Microflora Imbalance in Patients with Obstructive Jaundice

    ObjectiveTo explore the variation of the structure of the intestinal flora between healthy people and patients with obstructive jaundice perioperatively. MethodsFrom February 2013 to August 2014, 20 patients with obstructive jaundice and 10 healthy persons (normal control group) in our hospitol were selected as the research object. The first stool specimens of the research object after admission were obtained and the total fecal bacteria DNA were extracted. After polymerase chain reaction amplification, the changes in the structure of bacterial flora were dynamic observed by using denaturing gradient gel electrophoresis (DGGE), and the gel bands were analyzed by using Quantity One software. The similarity and diversity of flora structure, and principal component analysis (PCA) were analyzed. ResultsSignificant differences of colonic microflora were found between patients with obstructive jaundice and healthy people; advantage intestinal flora in obstructive jaundice patients was significant lower than the normal control group. With the extension of time and degree of obstruction aggravated, a descending trend was found in number, abundance, and diversity of the intestinal microflora (P < 0.05). ConclusionThere is significant differences in the structure of colon bacteria in patients with obstructive jaundice and healthy persons.

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  • Preliminary study of the diagnostic value of wideband absorbance in adenoid hypertrophy children with type A tympanogram

    ObjectiveTo investigate the differences in middle ear function between adenoid hypertrophy (AH) children with type A tympanogram and normal children, and to evaluate the value of wideband acoustic immittance (WAI) in diagnosing middle ear dysfunction in AH children with type A tympanogram. MethodsThis retrospective cohort study included 96 children (192 ears) with AH and 40 healthy children (80 ears) as the control group. All children underwent pure tone audiometry, 226 Hz tympanometry, WAI, otoscopy, and electronic nasopharyngoscopy. Type A AH children were selected as the study group (AH group) to compare the 226 Hz tympanometry index and WAI between the two groups. A binary logistic regression model was constructed after dimensionality reduction by principal component analysis of the frequencies with statistical significance, and the diagnostic value of the model was evaluated by receiver operating characteristic (ROC) curve. ResultsThere was no significant difference in 226 Hz tympanometry between the two groups (P>0.05). This study found that there were significant differences in WAI between children with AH and healthy children. Under tympanic peak pressure, the wideband absorbance (WBA) of the AH group was significantly higher than that of the control group at 226~630 Hz and 3 150~6 000 Hz; Under ambient pressure, the WBA of the AH group was significantly lower than that of the control group at 1 250~1 600 Hz and significantly higher than that of the control group at 4 000~6 000 Hz. The dimensionality of 15 statistically significant frequencies was reduced to 3 principal components (89.79% of the original information) by principal component analysis. The binary logistic regression model constructed after dimensionality reduction by principal component analysis had a high diagnostic value, with an AUC of 0.813, a sensitivity of 62.18%, and a specificity of 87.50%. ConclusionWAI can be used as an effective method for evaluating the middle ear function of AH children with type A tympanogram.

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