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1.
A few constitutive cytochrome P-450 isozymes in male rat liver microsomes catalyzed the metabolism of benzo[a]pyrene (BP) in cumene hydroperoxide (CHP)-dependent reactions, which produced predominantly 3-hydroxyBP and BP quinones. This process varied with the concentration of CHP. At 0.05 mM CHP, 3-hydroxyBP was the major metabolite. An increase in CHP concentration reduced 3-hydroxyBP formation but increased the level of BP quinones. This change in metabolic profile was reversed by preincubation with pyrene. Pyrene selectively inhibited quinone formation and enhanced 3-hydroxyBP formation. Naphthalene, phenanthrene and benz[a]anthracene nonspecifically inhibited total metabolism. BP binding to microsomal protein correlated with quinone formation, suggesting a common precursor reactive intermediate. BP metabolism by female rat liver microsomes also depended on CHP concentration but was much less effective than that in the male. With females, quinones were the major metabolites at all CHP concentrations, and their formation was again modulated by pyrene. These data indicate that two distinct binding sites are responsible for the formation of 3-hydroxyBP and BP quinones.  相似文献   
2.
This paper presents the results of a qualitative study conducted by midwife researchers into women's experience of new motherhood. Data were collected using focus groups involving 55 first-time mothers and analysed using grounded theory method. The analysis produced six categories: 'realizing', 'unready', 'drained', 'aloneness', 'loss' and 'working it out'. The core category, 'becoming a mother', integrates all other categories and encapsulates the process of change experienced by women. Also explained are factors mediating the often distressing experience of becoming a mother. The analysis provides a conceptualization of early motherhood enabling the development of strategies for midwives, nurses and others helping women negotiate this challenge.  相似文献   
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This paper describes the tragic case of a young woman who died of cancer of the colon after successfully donating eggs to her younger sister. Although there is no direct link between her operation and the subsequent development of bowel carcinoma, this case imparts a feeling of unease when seen in conjunction with other cases reported during the last few years. It is a reminder that little is known of the long-term consequences of some aspects of assisted conception. Women undergoing ovarian stimulation for themselves or a matched recipient have the right to be advised, in an agreed format, that there is some concern about unproven potential risks from the stimulatory drugs. The safety of egg donors must assume priority over all other considerations, including lack of donors or any moral position. The recent decision by the Human Fertilisation and Embryology Authority (HFEA) to withdraw any form of payment or recompense to egg donors does not seem to us to be based on a balance of scientific advances, patient needs and the ethics of gamete supply. They state that the intention to withdraw payments was implicit in the 1990 Human Fertilisation and Embryology (HFE) Act. However the Act was based on the Warnock report made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility drugs had not yet caused any unease. The Act provided the HFEA with discretionary powers to issue directions so that the future policies would be consistent with any emerging new medical evidence. It is imperative that the HFEA provide convincing evidence on how the current policy of payment to donors harms society, donors or recipients, and how in the UK the new policy will improve medical practice in assisted conception. Successful pilot studies must precede the implementation of any new policy. Failure to do this could cause irreversible harm to the practice of assisted conception using donor gametes, which will ultimately be against the basic aims of the 1990 HFE Act.   相似文献   
5.
Brother were affected with severe congenital contractures, multiple cutaneous manifestations of ectodermal dysplasia, cleft lip/palate, and psychomotor and growth impairment. High resolution prometaphase chromosomes were normal. Molecular studies of DNA markers, closely flanking the X-linked hypohidrotic ectodermal dysplasia locus, did not show evidence of a submicroscopic deletion from the Xq12-q13 region. The parents and a normal sister exhibited none of these findings. This constellation of anomalies appears to represent a unique AR or XLR syndrome. © 1993 Wiley-Liss, Inc.  相似文献   
6.
Chromosomal rearrangements are frequently monitored by fluorescence in situ hybridization (FISH) using large, recombinant DNA probes consisting of contiguous genomic intervals that are often distant from disease loci. We developed smaller, targeted, single-copy probes directly from the human genome sequence. These single-copy FISH (scFISH) probes were designed by computational sequence analysis of approximately 100-kb genomic sequences. ScFISH probes are produced by long PCR, then purified, labeled, and hybridized individually or in combination to human chromosomes. Preannealing or blocking with unlabeled, repetitive DNA is unnecessary, as scFISH probes lack repetitive DNA sequences. The hybridization results are analogous to conventional FISH, except that shorter probes can be readily visualized. Combinations of probes from the same region gave single hybridization signals on metaphase chromosomes. ScFISH probes are produced directly from genomic DNA, and thus more quickly than by recombinant DNA techniques. We developed single-copy probes for three chromosomal regions-the CDC2L1 (chromosome 1p36), MAGEL2 (chromosome 15q11.2), and HIRA (chromosome 22q11.2) genes-and show their utility for FISH. The smallest probe tested was 2290 bp in length. To assess the potential utility of scFISH for high-resolution analysis, we determined chromosomal distributions of such probes. Single-copy intervals of this length or greater are separated by an average of 29.2 and 22.3 kb on chromosomes 21 and 22, respectively. This indicates that abnormalities seen on metaphase chromosomes could be characterized with scFISH probes at a resolution greater than previously possible.  相似文献   
7.
NHEXAS AZ is a multimedia, multipathway exposure assessment survey designed to evaluate metals and other analytes. This paper reports the analyte-specific concentration distributions in each of the media examined (air, soil, house dust, food, beverage, and water), for various methodologies used (inductively coupled plasma-atomic emission spectroscopy and hydride generation-atomic absorption spectroscopy). Results are reported for the five primary metals (Pb, As, Cd, Cr, and Ni). Ingestion was the most important pathway of exposure. Metal concentrations in air were very low (ng/m3) and found only above the 90th percentile. Metals were commonly found in house dust and soil. Exposure transfer coefficients minimize the importance of this component for those over the age of 6 years. When ranked by exposure, food, beverage, and water appeared to be the primary contributors of metal exposure in NHEXAS AZ. For instance, at the 90th percentile, Pb was undetected in air, found at 131 and 118 microg/m3 in floor dust and soil, respectively, and measured at 16 microg/kg in food, 7.1 microg/kg in beverage, and 2.0 and 1.3 microg/l in drinking and tap water, respectively. We calculated preliminary estimates of total exposure (microg/day) for each participant and examined them independently by age, gender, and ethnicity as reported by the subjects in the NHEXAS questionnaire. At the 90th percentile for Pb, total exposures were 64 microg/day across all subjects (n=176); adult men (n=55) had the greatest exposure (73 microg/day) and children (n=35) the least (37 microg/day). Hispanics (n=54) had greater exposure to Pb (68 microg/day) than non-Hispanics (n=119; 50 microg/day), whereas non-Hispanics had greater exposure for all other metals reported. These results have implications related to environmental justice. The NHEXAS project provides information to make informed decisions for protecting and promoting appropriate public health policy.  相似文献   
8.

Introduction  

This report describes the isolation and characterization of three new murine mammary epithelial cell lines derived from mammary tumors from MMTV (mouse mammary tumor virus)/activated Neu + TβRII-AS (transforming growth factor [TGF]-β type II receptor antisense RNA) bigenic mice (BRI-JM01 and BRI-JM05 cell lines) and MMTV/activated Neu transgenic mice (BRI-JM04 cell line).  相似文献   
9.
OBJECTIVE: To assess the antibody response to influenza vaccine of children vertically infected with HIV. DESIGN: Prospective study in HIV infected children vaccinated during the winter of 1994-5. SETTING: Family HIV clinic at St Mary's Hospital, Paddington. SUBJECTS: 25 children, aged 1-11 years, vertically infected with HIV. MAIN OUTCOME MEASURES: Responses to influenza antigens (H1N1-A/Taiwan/1/86, H3N2-A/Shandong/9/93, B/Panama/45/ 90) were tested by haemagglutination inhibition. Antibody responses were assessed according to clinical symptoms and immune function, stratified according to the 1994 revised classification for HIV infection in children. RESULTS: 23 children (92%) had either very low or no detectable antibody before vaccination. New protective antibody responses were made by 10 children (40%): in seven to a single antigen, in two to two antigens, and in one to all three antigens. For each antigen there was an overall small increase in the mean geometric titre of antibody produced, but this only reached a protective level for antigen H1N1 and for children with minimal symptoms. Less symptomatic children were significantly more likely to produce a protective antibody response to influenza vaccination. No association was found between immune function, as measured by CD4 count, and vaccine response. CONCLUSIONS: Only vaccination of the least symptomatic HIV infected children against influenza is likely to be effective. This will not only protect them against influenza, but will also protect other more immunosuppressed and vulnerable members of their families.  相似文献   
10.
porter s., holmes v., mclaughlin k., lynn f., cardwell c., braiden h.-j., doran j. & rogan s. (2012)?Music in mind, a randomized controlled trial of music therapy for young people with behavioural and emotional problems: study protocol. Journal of Advanced Nursing68(10), 2349-2358. ABSTRACT: Aims. This article is a report of a trial protocol to determine if improvizational music therapy leads to clinically significant improvement in communication and interaction skills for young people experiencing social, emotional or behavioural problems. Background. Music therapy is often considered an effective intervention for young people experiencing social, emotional or behavioural difficulties. However, this assumption lacks empirical evidence. Study design. Music in mind is a multi-centred single-blind randomized controlled trial involving 200 young people (aged 8-16?years) and their parents. Eligible participants will have a working diagnosis within the ambit of International Classification of Disease 10 Mental and Behavioural Disorders and will be recruited over 15?months from six centres within the Child and Adolescent Mental Health Services of a large health and social care trust in Northern Ireland. Participants will be randomly allocated in a 1:1 ratio to receive standard care alone or standard care plus 12 weekly music therapy sessions delivered by the Northern Ireland Music Therapy Trust. Baseline data will be collected from young people and their parents using standardized outcome measures for communicative and interaction skills (primary endpoint), self-esteem, social functioning, depression and family functioning. Follow-up data will be collected 1 and 13?weeks after the final music therapy session. A cost-effectiveness analysis will also be carried out. Discussion. This study will be the largest trial to date examining the effect of music therapy on young people experiencing social, emotional or behavioural difficulties and will provide empirical evidence for the use of music therapy among this population. Trial registration. This study is registered in the ISRCTN Register, ISRCTN96352204. Ethical approval was gained in October 2010.  相似文献   
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