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81.
BACKGROUND AND PURPOSE: Hypertrophic cardiomyopathy (HCM) is characterized by symmetric or asymmetric hypertrophy of the left and/or right ventricle. Morphologic and pathologic indices (MI and PI) of hearts were established for classification of HCM in pigs. METHODS: Fifty on-farm-performance-tested pigs (average body weight, 104.3 kg; age, 224.5 days) were randomly selected. Heart weight, length, width, heart-to-body weight ratio, and thickness of the cranial and middle portions of ventricular septum and left ventricular free wall were measured. Myocyte disorganization and necrosis, myocardial and endocardial fibrosis, and intramural coronary arterial occlusion were scored. Principal component analysis and stepwise regression analysis were used to establish MI and PI. RESULTS: MI was established by using the first principal component as the dependent variable and applying stepwise regression analysis. Hearts were classified as morphologically normal, suspicious, and hypertrophic according to the range of MI. The same statistical method was used to find PI. Hearts were classified as pathologically normal, moderately affected, or seriously affected according to the range of PI. Combining MI and PI, hearts could be classified into five groups: no hypertrophy with minor lesion (normal); hypertrophy but with rare lesion; no hypertrophy but seriously affected; suspicious; and hypertrophy and seriously affected (heart with HCM). Another 119 hearts were collected and classified. The variation of heart measurements was consistent with the original purpose of classification. CONCLUSIONS: Using fewer measurements for identification of HCM objectively in pigs seems to have practical application.  相似文献   
82.

Background  

Activity of secreted phospholipase A (sPLA2) has been implicated in a wide range of cellular responses. However, little is known about the function of human parvovirus B19-VP1 unique region (VP1u) with sPLA2 activity on macrophage.  相似文献   
83.
Using microarray analysis, we identified a unique ras superfamily gene, termed RERG (ras-related and estrogen-regulated growth inhibitor), whose expression was decreased or lost in a significant percentage of primary human breast tumors that show a poor clinical prognosis. Importantly, high RERG expression correlated with expression of a set of genes that define a breast tumor subtype that is estrogen receptor-positive and associated with a slow rate of tumor cell proliferation and a favorable prognosis for these cancer patients. RERG mRNA expression was induced rapidly in MCF-7 cells stimulated by beta-estradiol and repressed by tamoxifen treatment. Like Ras, RERG protein exhibited intrinsic GDP/GTP binding and GTP hydrolysis activity. Unlike Ras proteins, RERG lacks a known recognition signal for COOH-terminal prenylation and was localized primarily in the cytoplasm. Expression of RERG protein in MCF-7 breast carcinoma cells resulted in a significant inhibition of both anchorage-dependent and anchorage-independent growth in vitro and inhibited tumor formation in nude mice. These features of RERG are strikingly different from most Ras superfamily GTP-binding pro-teins and suggest that the loss of RERG expression may contribute to breast tumorigenesis.  相似文献   
84.
Liu J  Ma H  He YL  Xie B  Xu YF  Tang HY  Li M  Hao W  Wang XD  Zhang MY  Ng CH  Goding M  Fraser J  Herrman H  Chiu HF  Chan SS  Chiu E  Yu X 《World psychiatry》2011,10(3):210-216
This paper summarizes the history of the development of Chinese mental health system; the current situation in the mental health field that China has to face in its effort to reform the system, including mental health burden, workforce and resources, as well as structural issues; the process of national mental health service reform, including how it was included into the national public health program, how it began as a training program and then became a treatment and intervention program, its unique training and capacity building model, and its outcomes and impacts; the barriers and challenges of the reform process; future suggestions for policy; and Chinese experiences as response to the international advocacy for the development of mental health.  相似文献   
85.
Chen  Hui-Mei  Chang  Tzu-Hao  Lin  Feng-Mao  Liang  Chao  Chiu  Chih-Min  Yang  Tzu-Ling  Yang  Ting  Huang  Chia-Yen  Cheng  Yeong-Nan  Chang  Yi-An  Chang  Po-Ya  Weng  Shun-Long 《BMC genomics》2018,19(10):876-178
Background

One of the most common and recurrent vaginal infections is bacterial vaginosis (BV). The diagnosis is based on changes to the “normal” vaginal microbiome; however, the normal microbiome appears to differ according to reproductive status and ethnicity, and even among individuals within these groups. The Amsel criteria and Nugent score test are widely used for diagnosing BV; however, these tests are based on different criteria, and so may indicate distinct changes in the vaginal microbial community. Nevertheless, few studies have compared the results of these test against metagenomics analysis.

Methods

Vaginal flora samples from 77 participants were classified according to the Amsel criteria and Nugent score test. The microbiota composition was analyzed using 16S ribosome RNA gene amplicon sequencing. Bioinformatics analysis and multivariate statistical analysis were used to evaluate the microbial diversity and function.

Results

Only 3 % of the participants diagnosed BV negative using the Amsel criteria (A−) were BV-positive according to the Nugent score test (N+), while over half of the BV-positive patients using the Amsel criteria (A+) were BV-negative according to the Nugent score test (N−). Thirteen genera showed significant differences in distribution among BV status defined by BV tests (e.g., A − N−, A + N− and A + N+). Variations in the four most abundant taxa, Lactobacillus, Gardnerella, Prevotella, and Escherichia, were responsible for most of this dissimilarity. Furthermore, vaginal microbial diversity differed significantly among the three groups classified by the Nugent score test (N−, N+, and intermediate flora), but not between the Amsel criteria groups. Numerous predictive microbial functions, such as bacterial chemotaxis and bacterial invasion of epithelial cells, differed significantly among multiple BV test, but not between the A− and A+ groups.

Conclusions

Metagenomics analysis can greatly expand our current understanding of vaginal microbial diversity in health and disease. Metagenomics profiling may also provide more reliable diagnostic criteria for BV testing.

  相似文献   
86.
87.
Chih HW  Chiu HF  Tang KS  Chang FR  Wu YC 《Life sciences》2001,69(11):1321-1331
Bullatacin, isolated from the fruit of Annona atemoya, is one of the most potentially effective antitumor annonaceous acetogenins. Bullatacin was studied here for its ability to inhibit the proliferation of 2.2.15 cells, hepatitis B virus (HBV) DNA transfected human hepatocarcinoma cell line. It was found that bullatacin induced cytotoxicity of 2.2.15 cells in a time- and dose-dependent manner. Fifty percent effective dose (ED50) on day 1 of exposure to bullatacin were 7.8 +/- 2.5 nM for 2.2.15 cells. [3H]-Thymidine incorporation assays showed almost the same results. Bullatacin-treatment also reduced concentrations of hepatitis B surface antigen (HBsAg) in the cultured medium released from 2.2.15 cells, coincident with the decrease in the cell proliferation. Analysis of mophological changes of bullatacin-treated 2.2.15 by inverted phase-contrast microscope and eletron microscopy revealed a possible model of action for bullatacin to inhibit proliferation of 2.2.15 cells by inducing apoptosis. Most of the bullatacin-induced cell death was found to be due to apoptosis, as determined by double staining with fluorescein-isothiocyanate (FITC)-labeled annexin V and propidium iodide (PI).  相似文献   
88.

Background, aim, and scope  

Life Cycle Assessment (LCA) is an emerging supporting tool designed to help practitioner in systematically assessing the environmental performance of selected product’s life cycle. A product’s life cycle includes the extraction of raw materials, production, and usage, and ends with waste treatment or disposal. Life cycle impact assessment (LCIA) as a part of LCA is a method used to derive the environmental burdens from selected product’s stages. LCIA is structured in classification, characterization, normalization and weighting. Presently most of the LCIA practices use European database to establish the characterization, normalization and weighting value. However, using these values for local LCA practice might not be able to reflect the actual Malaysian’s environmental scenario. The aim of this study is to create a Malaysian version of normalization and weighting value using the pollution database within Malaysia.  相似文献   
89.
Three-dimensional structure of rotavirus   总被引:40,自引:0,他引:40  
  相似文献   
90.
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