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Xin Song

Publications and source records attributed to Xin Song.

26 records · Page 2Linked to original sources
PubMed2004

[A review of basic statistics concepts,research design and statistical analysis methods].

Statistics is a methodology involving a great number of statistical methods. It results in confusion of many clinicians and researchers while they are meditating on how to analyze the collected data in their studies, selecting an appropriate statistical method from all. In fact, the statistical methods are closely correlated to the research design and the data types. Therefore only with a full comprehension of the design methods and the data types can we figure out a simple and practical means from diverse statistical analysis methods. Through the systematic illustration in this review, several statistical concepts, data types, design methods, and the proper way of explaining results with statistical tables and graphs will be demonstrated elaborately. It intends to help the clinicians and researchers select appropriate statistical methods and furthermore, interpret the statistical outcomes accurately in their research.

Humans↗
PubMed2004

[Pathologic diagnoses of core needle biopsies of the mediastinum].

OBJECTIVES: To assess the diagnostic accuracy and to study the histologic typing of mediastinal lesions using core needle biopsies. METHODS: The histopathology and immunophenotype of 65 mediastinal core needle biopsy specimens were studied retrospectively by light microscopy and immunohistochemical staining (ABC method). Gene rearrangement studies were performed in some of the non-Hodgkin's lymphomas cases using PCR. Follow-up records were also analyzed. RESULTS: Morphologically, all specimens showed a combination of epithelioid cells, lymphoid cells and fibrous tissue in different proportions. The pathologic diagnoses included lymphoma (21 cases), pulmonary carcinoma (20 cases), thymoma (14 cases), thymic carcinoma (4 cases), seminoma (3 cases) and chronic inflammation (1 case). Definitive diagnosis was not possible in 2 cases due to insufficient material. The tumor cells in lymphoma (21 cases) expressed CD20, CD3, TDT, CD30, CD15 or EMA, depending on their histologic subtypes. Tumor cells in the 17 pulmonary carcinoma cases expressed cytokeratin (CK), except 3 cases of small cell carcinoma of lung. Synaptophysin, chromogranin A and neuron-specific enolase were all positive in the 10 cases of small cell carcinoma of lung and 1 case of thymic small cell carcinoma (which was also CD5 negative). The 3 cases of adenocarcinoma of lung showed positivity for thyroid transcription factor-1 (TTF-1) and they were negative for CD5. The 14 thymoma cases expressed CK, CD3 or CD20. The 3 thymic carcinoma cases expressed CK and CD5. Placental-like alkaline phosphatase (PLAP) was positive in 3 seminoma cases which were CK-negative. Immunoglobulin heavy chain gene was rearranged in the 3 cases of diffuse large B-cell lymphoma and 1 B-cell anaplastic large cell lymphoma case. T-cell receptor beta gene was rearranged in 5 T-cell lymphoblastic lymphoma cases. CONCLUSIONS: Microscopic assessment of tissue samples from mediastinal core needle biopsies should be made in combination with clinical and radiologic information. Ancillary investigations, including immunohistochemical staining and/or gene rearrangement studie, are needed in both non-lymphoma and lymphoma cases of mediastinum.

Adolescent↗
PubMed2004

[A review of statistical analysis methods in measurement data].

Measurement data, which is obtained by measuring the size of numeric value, is consisted of numerical variables. In clinic research, the collected data covers quite of numerical variables. Composed of those numerical variables, the measurement data has to be correspondingly analyzed in the special statistical methods in the light of their design methods. The statistical methods of measurement data include descriptive statistics and inferential statistics. Descriptive statistics is mainly used to describe the distribution laws and the characters/features of the data. For instance, when measuring the central tendency and dispersion tendency of the data, methods such as calculating the mean and the standard deviation can be considered. Inferential statistics is mainly employed to estimate the confidence limit such as estimating the 95% confidence interval and to have the hypothesis testing in the example of having t test and analysis of variance. By highlighting the specific statistical methods of measurement data, this review intends to help the clinicians and researchers select correct statistical methods in accordance with measurement data.

Data Interpretation, Statistical↗
PubMed2004

[A review of correlation, regression and multiple factors analysis methods.].

In clinical research, the relationships between two factors or among multiple factors are frequently explored. Dependence and covariation are two kinds of relationships between two factors. Regression and correlation analysis are the appropriate methods in measuring and evaluating those factors. Multiple analysis methods are widely used in the studies of risk factors among diseases, data analyses of diagnostic tests, effects evaluation of a prevention and treatment, analyses of prognosis, etc. Multiple analysis methods could interpret the influences of each factor more specifically than single factor analysis, and provide more possibilities to improve the quality of a research. In this review, the fundamental principle and utilities on clinical research of several statistical methods are introduced in this paper, such as linear correlation, linear regression, rank regression, rank correlation, multiple linear regression and logistic regression. It intends to help the clinicians and researchers to select the appropriate statistical methods to collect and analyze the data.

Epidemiologic Studies↗
PubMed2004

[A review of nonparametric test].

For some data which have skewness distribution or unknown distribution, it is impossible to apply parametric test. Nonparametric test will be a good choice for this kind of data in testing the distribution of the population. The nonparametric test is widely used in clinical research by its goodness of stability and adaptiveness. However, the effectiveness is cutting down by losing some essential information. So, parametric test will be recommended when the data meet the requirements. This paper introduces the basic concepts and methods of nonparametric test for the physicians to understand this important tool.

Humans↗
PubMed2003

Loss of fragile histidine triad protein in human hepatocellular carcinoma.

AIM: To investigate the expression of fragile histidine triad (FHIT) gene protein, Fhit, which is recently thought to be a candidate tumor suppressor. Abnormal expression of fragile histidine triad has been found in a variety of human cancers, but little is known about its expression in human hepatocellular carcinogenesis and evolution. METHODS: Sections of 83 primary human hepatocellular carcionoma with corresponding para-neoplastic liver tissue and 10 normal liver tissue were evaluated immunohistochemically for Fhit protein expression. RESULTS: All normal liver tissue and para-neoplastic liver tissue showed a strong expression of Fhit, whereas 50 of 83 (65.0 %) carcinomas showed a marked loss or absence of Fhit expression. The differences of Fhit expression between carcinoma and normal or para-neoplastic liver tissue were highly significant (P=0.000). The proportion of carcinomas with reduced Fhit expression showed an increasing trend (a) with decreasing differentiation or higher histological grade (P=0.219); (b) in tumors with higher clinical stage III and IV (91.3 %, P=0.000), compared with tumors with lower stage I and II (27.6 %); and (c) in cancers with bigger tumor size (>50 mm) (75.0 %, P=0.017), compared with smaller tumor size (< or = 50 mm). CONCLUSION: FHIT inactivation seems to be both an early and a later event, associated with carcinogenesis and progression to more aggressive hepatocellular carcinomas. Thus, evaluation of Fhit expression by immunohistochemistry in hepatocellular carcinoma may provide important diagnostic and prognostic information in clinical application.

Acid Anhydride Hydrolases↗
PubMed2003

[Epstein-Barr virus inhibits P16INK4a expression in human fetal nasopharyngeal epithelial cells escaping from the replicative senenscence].

Cell cycle deregulation is regarded as an important event to involve in cellular immortalization. To confirm the role of cell cycle deregulation in human fetal nasopharyngeal epithelial cells escaping from the replicative senescence induced by Epstein-Barr virus infection, we detected expression of cell cycle regulators, such as p16INK4a, p21WAF1/CIP1, p53, and E2F1 with Western blotting and immunocytochemisty in this study. Our results found that Epstein-Barr virus inhibited the expression of p16INK4a, at the same time, E2F1 expression were strongly increased in EBV-infected cells, however, as for the expression of p53 and p21WAF1/CIP1, there was no difference between EBV-infected cells and non-infected cells. The results show that EBV inactivates p16INK4a/pRB pathway and then induces E2F1 activity and it is implicated that Epstein-Barr virus-medicated cell cycle deregulation plays an important role in the immortalization of human nasopharyngeal epithelial cells. These data will be helpful for further studying the carcinogenesis of nasopharyngeal carcinoma.

Cell Transformation, Neoplastic↗