Search PubMed⌕ Search

Biomedical subjects

A Walker

Publications and source records attributed to A Walker.

At least 19 recordsLinked to original sources
PubMed1992

Prognosis for breast cancer surgery and radiation therapy compared with mastectomy alone. A retrospective analysis of 759 patients with stage I/II breast cancer.

Seven hundred fifty-nine patients with Stage I/II breast cancer who were treated with mastectomy alone (558 patients) or breast-conserving surgery and tangential irradiation (201 patients) were evaluated. Median follow-up time was 34 months. Axillary node status showed differences between treatment groups. Seventy-two percent of patients undergoing lumpectomy and radiation therapy (Lx) versus 35% of patients in the mastectomy group were pathologically node-negative, 18% Lx versus 30% mastectomy alone had one to three nodes positive, and four or more positive axillary nodes were seen in 35% of mastectomy alone patients. Reflecting this trend, overall survival (P less than 0.007), time to locoregional failure (P less than 0.0005), and time to any failure (P less than 0.0001) favored Lx patients. Correcting for axillary node status, significant differences persisted only for node-negative patients. Median actuarial survival time was 73 months for the mastectomy alone group (196 patients) versus 120 months for the Lx group (144 patients) (P less than 0.02), with significant differences also noted in time to local failure (P less than 0.003) and time to any failure (P less than 0.001). Stratification according to primary tumor size in patients who were node-negative yielded marked differences in time to locoregional failure in T1 (less than 2 cm) (P less than 0.0006) presentations, with analysis approaching significance for T2 (2 to 5 cm) lesions (P less than 0.06). Disease-free interval was greater in node-negative Lx patients for both T1 (P less than 0.007) and T2 (P less than 0.05) presentations. Overall survival was not significantly different in node-negative Lx patients when primary tumor size was considered. Improved prognosis was identified in node-negative patients undergoing breast-conserving surgery and radiation therapy over mastectomy alone. Theoretical considerations included eradication of occult microscopic disease within the chest wall by tangential irradiation.

Adult↗
PubMed1992

A revised estimate of twin concordance in systemic lupus erythematosus.

OBJECTIVE: Based on a small clinical series and previously published case reports, concordance for systemic lupus erythematosus (SLE) among monozygous (MZ) twins has been reported to be as high as 69%. Using a larger and less biased sample, we provide another estimate of this percentage. METHODS: We established a registry of twins with SLE, based upon self-reports and information provided by the patients' physicians. We used DNA fingerprinting to validate the reported zygosity in a sample of these twins. RESULTS: Of 107 twin pairs meeting the American College of Rheumatology 1982 revised criteria for the diagnosis of SLE, 24% of 45 MZ pairs and 2% of 62 dizygous (DZ) pairs were concordant. The frequency distributions of diagnostic criteria and disease symptoms in the SLE patients were similar to those in other published reports of SLE patients. Zygosity was confirmed by DNA fingerprinting in a subsample of 15 self-described MZ twins and 7 self-described DZ twins. All individuals had correctly predicted their zygosity. CONCLUSION: MZ concordance for SLE is similar to that for other autoimmune diseases and is much lower than previously believed.

Adolescent↗
PubMed1992

Hormone-regulated v-rel estrogen receptor fusion protein: reversible induction of cell transformation and cellular gene expression.

We describe the construction of a v-rel estrogen receptor fusion protein (v-relER) which allows the regulation of v-rel oncoprotein activity by hormone. In the presence of estrogen, v-relER readily transformed primary chicken fibroblasts and bone marrow cells in vitro. In both cell types, v-rel-specific transformation was critically dependent on the presence of estrogen or the estrogen agonist 4-hydroxytamoxifen (OHT). Withdrawal of estrogen or application of an estrogen antagonist, ICI164,384 (ICI) caused a reversal of the transformed phenotype. We also demonstrate that the v-relER protein binds to NF-kappa B sites in an estrogen-dependent manner, thereby showing that sequence-specific DNA binding of v-relER is critical for the activation of its transforming capacity. In transient transfection experiments, we failed to demonstrate a clear repressor or activator function of the v-rel moiety in v-relER. However, in v-relER-transformed bone marrow cells, estrogen and OHT induced elevated mRNA levels of two cellular genes whose expression is constitutive and high in v-rel-transformed cells. These results suggest that v-rel might exert part of its activity as an activator of rel-responsive genes.

Animals↗
PubMed1992

Sialolithiasis of minor salivary glands.

Sialolithiasis of minor salivary glands is generally considered to be extremely rare. Reports of seven cases are presented. A review of the literature suggests that the condition is not as uncommon as previously considered, and that definitive histopathological diagnosis of lip swellings should be obtained due to the incidence of labial pleomorphic adenoma and the possibility of the clinical misdiagnosis with sialolithiasis.

Adult↗
PubMed1992

Haemoglobin F levels in sudden infant deaths.

Fetal haemoglobin levels have been measured prospectively in 135 autopsy cases of sudden, unexpected infant deaths (31 pre-term, 104 full term) using standard laboratory methods. These results have been compared with Hb F values from a normal control group of 570 living infants (145 pre-term, 425 full-term) with a post-conceptional age < 90 weeks. The gestational age was established for all live controls and sudden infant deaths. The results show that full-term (> 38 weeks gestational age) sudden infant death victims as a group have significantly elevated Hb F levels (chi 2 = 25.20, P < 0.001) when compared to the gestational age matched control group. Pre-term (< 38 weeks gestational age) SIDs show no significant differences from the pre-term control group (chi 2 = 1.20, n.s.) The division of the controls into pre- and full-term groups demonstrates major differences between the post-natal Hb F fall in pre- and full-term infants. Use of post-conceptional age as a growth marker does not produce comparability with full-term infants. Extensive controls were carried out to confirm the reliability of post-mortem Hb F assays, and comparability with in vivo estimation. No significant or systematic differences between pre- and post-mortem samples were identified, nor were any significant differences found on post-mortem storage up to 72 h.

Bacterial Infections↗
PubMed1992

Contributions of incidence and case fatality to mortality from bladder cancer in the south Thames Regions.

STUDY OBJECTIVE: The aim was to assess the individual contributions of incidence and case fatality to variations in bladder cancer mortality between districts in the South Thames Regions. DESIGN: The standardised mortality ratios for bladder cancer were calculated for the health districts in the South Thames Regions using data from the Thames Cancer Registry. The results were compared with the standardised registration ratios, used as a measurement of incidence, and survival hazard function, used as a measurement of case fatality. As one determinant of case fatality is the severity at presentation, mortality was also compared with the standardised proportion of cases with advanced disease at diagnosis. SETTING: The study took place in the 28 health districts in South East and South West Thames regional health authorities. SUBJECTS: Subjects were 3271 cases of bladder cancer aged 15-74 years resident in one of the two South Thames regional health authorities at diagnosis and registered between 1982 and 1985. MAIN RESULTS: The standardised mortality ratios for the different districts varied from 62 to 139. The standardised registration ratios, the survival hazard functions adjusted for age and stage of disease at diagnosis, and the proportion of cases with severe disease at diagnosis were all independently and significantly related to the standardised mortality ratios in each district. CONCLUSIONS: Mortality from bladder cancer was significantly related to measurements of incidence, case fatality, and severity at presentation. These relations have implications for the health services. The incidence of disease may be modified through preventative measures, the case fatality through improved quality of care, and severity at presentation possibly through prompt management of patients with haematuria. Further studies are needed to investigate why these factors have high values in some districts.

Adolescent↗
PubMed1992

The persistence of poverty under welfare states and the prospects for its abolition.

This article examines the relationship between poverty and the welfare state and attempts to answer the question as to why poverty has persisted under all welfare states. Several major reasons for the persistence of poverty are advanced, and the author argues that the main factor underlying the failure to abolish poverty is the conflict between economic policy and social policy. The challenge to welfare states from the New Right is examined--particularly the contention that welfare states themselves create poverty and dependence--in the light of evidence of the impact of the Thatcher government's policies in Britain. Finally, the author proposes an alternative approach to the abolition of poverty, one that is based on the integration of economic and social policy.

Employment↗
PubMed1991

Surgeons and HIV.

Explore the source record for details and available documents.

General Surgery↗
PubMed1991

Oral contraceptives, androgens, and the sexuality of young women: I. A comparison of sexual experience, sexual attitudes, and gender role in oral contraceptive users and nonusers.

Female undergraduates (108) volunteered for a study of hormones and sexuality, 55 of whom were oral contraceptive (OC) users. In this paper, OC users and nonusers are compared on measures of sexual attitudes and behavior, use of erotic fantasy, and gender role. In the second paper, the effects of OC on androgen levels and the relationship between androgens and behavioral measures within each group are reported. OC users were more likely to have a current sexual partner and less likely to be virgins. The two groups did not differ in frequency of masturbation or use of erotic fantasies. OC users reported less restrictive sexual morality and more interest in erotic images. These differences persisted when women without current partners were excluded. Among those in active sexual relationships, OC users reported more frequent sexual intercourse, higher psychosexual motivation and enjoyment, and were more positive in their evaluation of their partners than OC nonusers.

Adult↗
PubMed1991

Oral contraceptives, androgens, and the sexuality of young women: II. The role of androgens.

The relationships between plasma free testosterone (FT) and measures of sexual attitude, sexual behavior, and gender role behavior were assessed in 55 oral contraceptive-using and 53 nonusing female undergraduates. Plasma FT and other measures of androgenicity were substantially lower in the oral contraceptive (OC) group. Correlations between FT and certain behavioral and attitudinal measures were found in the OC users but not the nonusers. In the OC users, FT was positively associated with frequency of sexual intercourse but not with frequency of masturbation. It was negatively associated with restrictive sexual morality. Correlations between FT and measures of gender role behavior were negligible, and FT was unrelated to proceptivity, homosexual interest, or the use of sexual fantasy. The occurrence of some predicted correlations among pill-using women but not the nonusers requires explanation, particularly in view of the substantially lower levels of FT in the pill-using group. It is suggested that androgen-behavior relationships in women are easily obscured by psychosocial influences and in this sample of young women such influences may have been more powerful among those not using OCs. Such psychosocial influences are likely to differ at different stages of women's life cycles. The importance of controlling for such influences in any study of hormone-sexual behavior relationships in women is emphasized, and the need for prospective studies of women before and after starting on steroidal contraception is recognized.

Adult↗
PubMed1991

The cost of screening for colorectal cancer.

STUDY OBJECTIVE: The aim was to make projections of the likely costs and yield resulting from the implementation of a faecal occult blood screening programme for colorectal cancer. DESIGN: Cost and clinical data were derived from the MRC colorectal screening trial currently in progress in Nottingham, UK. SETTING: The above data were used as the basis for modelling the likely implications were the trial to be reproduced as a screening programme within a "typical" family practitioner committee area. MAIN RESULTS: For an average family practitioner committee area with a target population of 75,000 subjects aged 50-74 years, the initial screening round might be expected to detect 85 cancers at a total cost of approximately 250,000 pounds. This represents a cost per cancer detected of 2700 pounds and a cost per person screened of approximately 5 pounds. For subsequent screening rounds, total costs might be expected to fall although average costs are likely to remain approximately constant. CONCLUSIONS: The model is successful in generating "order of magnitude" estimates for the costs of implementation of a screening programme for colorectal cancer. As benefit estimates are not yet available, however, no cost-effectiveness analysis can be undertaken at this stage. In general, sensitivity analyses reveal that programme costs are more sensitive to changes in clinical variables, especially detection and compliance rates, than they are to variations in the costs of resource inputs. A screening programme with a more elaborate protocol than that currently employed in the Nottingham trial will entail considerable cost increases.

Colonic Neoplasms↗
PubMed1991

Quantitative assessment of a new dental imaging system.

The "Radiovisiography" dental imaging unit (Trophy UK Ltd) is a digital system using an intensifying screen and charge-coupled device in an intra-oral sensor. This paper presents a description of the system and an assessment of the original model in terms of patient dose (relative to film systems), resolution (limiting resolution and modulation transfer function), distortion and image noise (amplitude). The system does offer the possibility of reduced patient exposure and minimal distortion, although resolution and latitude are inferior to standard dental film.

Humans↗