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Five natural, pharmaceutical, or xenobiotic chemicals [17beta-estradiol (E2), ethynylestradiol (EE2), diethystilbestrol (DES), methoxychlor (MXC), nonylphenol (NP)] were tested in two in vitro assays [yeast estrogen screen (YES), MCF-7 breast tumor cell proliferation (E-Screen)], and compared with previously reported results from two in vivo male sheepshead minnow vitellogenin (VTG) production studies. The purpose of this investigation was to determine how accurately the two in vitro assays predicted responses observed in live animals. EC50 values for all five chemicals were approximately one order of magnitude less sensitive in the YES assay than in the MCF-7 assay. Based on the EC50 values, DES was 1.1 (YES) to 2.5 (MCF-7) times more potent in these receptor binding assays than was E2, while EE2 was slightly less potent than E2 in the YES assay (0.7) and nearly twice as potent (1.9) as E2 in the MCF-7 assay. EE2 and DES were of approximately equal potency in the 13-day sheepshead minnow VTG production bioassay. Both MXC and NP were 10(7) times less potent than E2 in the YES assay, MXC was 10(5) times less estrogenic than E2 in the MCF-7 assay, while both were approximately 100 times less potent than E2 in the live animal bioassay. The in vitro tests were substantially less sensitive (at least 1000 times) than the sheepshead minnow VTG assay for estimating estrogenic potency of the two xenobiotic chemicals, which suggests that in vitro-based, large-scale screening programs could potentially result in many false negative evaluations.  相似文献   
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Eleven major isoflavonoids and three major astragalosides in the xylem and bark of cultivated Radix Astragali (RA) from different cultivated regions of China were determined by high performance liquid chromatography. The results showed that the contents of astragalosides in the bark are up to 74-fold higher than in the xylem, and that thin roots contained more astragalosides than thick roots. Although the contents of isoflavonoids varied between samples, no significant difference was observed between the isoflavonoids content of xylem and bark, or between that of thin and thick roots. It was also found that the chemical profile of isoflavonoids in the xylem and bark are related to their cultivated regions. Constituents in either xylem or bark were divided into five groups according to their chemical structures: (1) Group 1 (G1), contained calycosin and related constituents; (2) Group 2 (G2), contained ononin and related constituents; (3) Group 3 (G3), contained (6aR,11aR)-3-hydroxy-9,10-dimethoxypterocarpan and related constituents; (4) Group 4 (G4), contained (3R)-7,2′-dihydroxy-3′,4′-dimethoxyisoflavan and related constituents; and (5) Group 5 (G5), contained astragalosides, compounds AG I, AG II, and AG IV. Based on the integrated contents of constituents in each group, the cultivated region of RA was successfully distinguished by principal components analysis (PCA). Chemical constituents in RA cultivated from different regions of China were compared and it was concluded that the quality of thin RA roots is better than thick RA roots.  相似文献   
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The incidence of hepatocellular carcinoma (HCC) is higher in Asian Americans than in other ethnicities. While hepatitis B virus (HBV) is common, hepatitis C virus (HCV) is more prevalent in some subgroups. Our goal was to determine the etiology of liver disease associated with HCC in subgroups of Asian Americans. This was an analysis of 510 Asian HCC patients at a US medical center. Patients were identified using ICD9 diagnosis. Multivariate logistic regression was used to study predictors of HCV as the cause of HCC. Patients were Southeast Asian, Chinese, and Korean, with similar gender, age, and foreign-born status. Southeast Asians had a similar proportion of HBV- and HCV-related HCC, while Chinese and Korean patients had a higher proportion of HBV-related HCC. HCC was usually associated with HBV in Chinese and Korean patients, but both HCV and HBV were important associations in Southeast Asians.  相似文献   
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Purpose: To investigate the relationship between disease factors, body functions and structures, activities, personal and environmental factors with independence in self-care activities in children with myelomeningocele (MMC), utilizing the International Classification of Function model.

Method: 113 children with MMC, aged 3–18 years were assessed during an annual MMC-clinic visit. Data on the personal and environmental factors, disease factors, hand function, mobility, visual perception, cognition, and communication were assessed in relation to the Pediatric Evaluation of Disability Inventory (PEDI) self-care domain.

Results: The mean PEDI caregiver assistance score was 22.1 (ranged between <10 and 62) well below the norms. The most significant determinant of dependence in self-care activities was the presence of hydrocephalus, a child with hydrocephalus scored a mean of 9.2 points less on the PEDI caregiver scale (p?=?0.02). By using a linear regression, the most significant factors associated with the PEDI scores among children with hydrocephalus were the age of the child, function of the non-dominant hand, ambulation, and cognitive function.

Conclusion: In children with MMC the presence of hydrocephalus appears to be more significantly associated with functional independence than the neurological level. The International Classification of Function model provides an in-depth multidisciplinary model that facilitates in investigating independence in self-care activities in children with MMC. It is important to take personal factors and various functional impairments into account when working with these children to promote independence.
  • Implications for Rehabilitation
  • When working with children with myelomeningocele on independence in daily living activities, it is necessary that health professionals demonstrate a holistic view of the child and his/her disability.

  • Health professionals should take into account information on all factors of the International Classification of Function, in order to help the children, achieve maximal independence.

  • It is important for health professionals to consider presence or lack of hydrocephalus when working with children with myelomeningocele to achieve functional gains.

  • Improving upper extremity function and cognitive ability in children with myelomeningocele may help promote independence in activities of daily living.

  • It is necessary for health professionals to continue to work with children with myelomeningocele on maximizing independence as they get older, for it is possible for them to achieve independence at a later age.

  • While this study did not explore participation, this is an essential part of the International Classification of Function and is generally related to function. Participation allows a child to be involved in life situations, contributes to life satisfaction and prepares children for critical adult roles. It is therefore important to assess and monitor this measure. Further studies should examine associations between independence in self-care activities and participation.

  相似文献   
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Limited data are available on the longitudinal occurrence of syndemic factors among women at risk for HIV infection in the USA and how these factors relate to sexual risk over time. HVTN 906 was a longitudinal study enrolling 799 HIV-uninfected women in three cities. Assessments were done at baseline, 6, 12, and 18 months to assess syndemic factors (low education, low income, unemployment, lack of health insurance, housing instability, substance use, heavy alcohol use, partner violence, incarceration) and sexual risk outcomes. For each sexual risk outcome, a GEE model was fit with syndemic factors or syndemic score (defined as sum of binary syndemics, ranging from 0 to 9), visit, study site, age and race/ethnicity as predictors to examine the multivariable association between syndemic factors and outcomes over time. Odds of unprotected sex while drunk or high were significantly higher when women reported lack of health insurance, substance and heavy alcohol use and partner violence. Housing instability, substance and heavy alcohol use, partner violence and recent incarceration were associated with higher odds of having multiple sexual partners. Odds of sex exchange were significantly higher in the presence of unemployment, housing instability, low education, lack of health insurance, substance and heavy alcohol use, partner violence and incarceration. Housing instability, substance and heavy alcohol use, and partner violence were significantly associated with higher odds of unprotected anal sex. Odds of having a recent STI were significantly higher when women reported housing instability and partner violence. There were significantly higher odds of the reporting of any risk outcomes during follow-up with higher syndemic score. This study highlights a group of women experiencing multiple poor social and health outcomes who need to be the focus of comprehensive interventions.  相似文献   
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AIDS and Behavior - We aimed to measure social protection coverage among the general population, women and men living with HIV (WLHIV, MLHV), female and male sex workers (FSW, MSW), men who have...  相似文献   
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