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Biomedical subjects

A Walker

Publications and source records attributed to A Walker.

At least 199 records · Page 11Linked to original sources
PubMed1993

New Australopithecus boisei calvaria from East Lake Turkana, Kenya.

The calvaria of an adult Australopithecus boisei from Area 104, Koobi Fora, Lake Turkana, is described. The specimen, KNM-ER 23000, comes from sediments dated to about 1.9 Ma. It consists of the frontal, both parietals, both temporals, most of the occipital as well as two small pieces of sphenoid, and a mandibular tooth root. The specimen is presumed to be an adult male, based on its size and the great development of features associated with the masticatory apparatus. KNM-ER 23000 is close in general size and shape to KNM-ER 406, KNM-ER 13750, and Olduvai Hominid 5 and it has a mixture of features seen in these three roughly contemporaneous crania. The frontal, especially the tori, resembles that of OH 5; the parietals are most like those of KNM-ER 13750; the occipital is like those of the two other Turkana specimens, and the temporals have a mixture of features from all of these, This specimen adds to our knowledge of variability in A. boisei.

Adult↗
PubMed1993

Vitamin C intake and plasma ascorbic acid concentration in adolescents.

The relationship between vitamin C intake and status was investigated in a group of adolescents (13-14 years old). Dietary intakes were assessed using a 7 d weighted dietary record method, coupled with the collection of duplicate diets. Vitamin C intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Vitamin C status was judged via measurement of plasma ascorbic acid (AA) concentration in blood samples taken after a 12-15 h fast. The relationship between calculated and analysed vitamin C intake and plasma AA concentration was examined. Average daily calculated vitamin C intakes, for the group (n 54) as a whole over a 7 d period, gave a good estimate of intake, as judged by prompt analysis of duplicate diets. However, analysed v. calculated intakes were significantly different for approximately one-third of subjects when data were examined on an individual basis. Large discrepancies between analysed and calculated values could not be accounted for on a food group basis. In all but two individuals, calculated vitamin C intake was in excess of the new reference nutrient intake (RNI, part of the new daily reference values (Department of Health and Social Security, 1991)) of 40 mg and all plasma AA concentrations were well above those used to indicate even a moderate risk of deficiency. A relationship between vitamin C intake and plasma AA was observed for both males (n 19) and females (n 35). However, the relationship was much stronger for males who showed a wider range of both intake and plasma AA values.

Adolescent↗
PubMed1993

Injuries sustained during flipping--a new fad activity.

This article describes a small series of injuries resulting from a new fad activity among children in Baltimore. "Flipping" involves jumping from an elevated surface and executing an aerial flip, with the intent to land upright. Because this activity takes place frequently on hard surfaces such as concrete, injuries often result. The spectrum of injuries is described and categorized, and injuries are compared with those received during similar activities, such as break dancing or skateboarding, and with playground injuries. Pediatricians and emergency physicians should be aware of the potential for injury in this activity.

Athletic Injuries↗
PubMed1993

Hepatic tumors: role of computed tomographic arterial portography in surgical planning.

Various imaging modalities currently used to evaluate liver tumors include magnetic resonance imaging, ultrasonography, contrast-enhanced computed tomography, and computed tomographic arterial portography. In our review of 28 cases, we found CT arterial portography to be very sensitive, and in 5 of these 28 cases CT arterial portography was a key factor in altering the course of therapy.

Adult↗
PubMed1993

Under new management: the changing role of the state in the care of older people in the United Kingdom.

This article examines recent changes and those currently being introduced in the formal care of older people in the United Kingdom. These are part of a general trend in all welfare states towards welfare pluralism but, in addition, the United Kingdom represents something of a special case because of the radical ideological engine that has driven the restructuring of the role of the state. The first part of the article outlines the main changes--the promotion of the private sector, the residualization of the public social services, and the new managerial role of the state in the care of older people. The second part considers the implications of these changes for older people and their informal helpers (or caregivers). The conclusion refers to both the particular changes taking place in the United Kingdom and, in general terms, to welfare pluralism as a policy goal.

Aged↗
PubMed1993

Cellular responses in experimental chronic and acute dermatophilosis infections of sheep.

The cellular infiltrate into the dermis in dermatophilosis lesions is composed of a range of cell types. The aim of this study was to establish if the composition of the cellular infiltrate in chronic lesions was different from that in healing lesions. Experimental Dermatophilus congolensis infections of sheep were used to study the sequential changes in cell types during the course of chronic and acute infections. Infestations of adult Amblyomma variegatum ticks were used to produce chronic lesions on infected sheep, infections of tick-free sheep provided acute lesions. Histopathology and immunohistochemistry were used to stain and label cell types in the dermis of infection sites. Neutrophils dominated the early response and were present in larger numbers in chronic lesions. Plasma cells were present in both types of lesion, however they persisted in chronic lesions but disappeared from the skin at acute lesion sites after the lesions had resolved. There were 2-3 times as many mononuclear cells in chronic than acute lesions from as early as 4 days post infection and these cells persisted in the chronic lesions. In the chronic lesions the mononuclear cell population was composed of T-helper and T-cytotoxic/suppressor lymphocytes in equal proportions whereas in acute lesions at 14 days post infection, when lesion resolution is underway, there were greater numbers of T-helper cells than T-cytotoxic/suppressor cells.

Actinomycetales Infections↗
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↗