PubMed Health⌕ Search

Biomedical subjects

D Timlin

Publications and source records attributed to D Timlin.

11 recordsLinked to original sources
PubMed2001

An innovative approach for locating and evaluating subsurface pathways for nitrogen loss.

Fundamental watershed-scale processes governing chemical flux to neighboring ecosystems are so poorly understood that effective strategies for mitigating chemical contamination cannot be formulated. Characterization of evapotranspiration, surface runoff, plant uptake, subsurface preferential flow, behavior of the chemicals in neighboring ecosystems, and an understanding of how crop management practices influence these processes are needed. Adequate characterization of subsurface flow has been especially difficult because conventional sampling methods are ineffective for measuring preferential flow of water and solutes. A sampling strategy based on ground-penetrating radar (GPR) mapping of subsurface structures coupled with near real-time soil moisture data, surface topography, remotely sensed imagery, and a geographic information system (GIS) appears to offer a means of accurately identifying subsurface preferential flow pathways. Four small adjacent watersheds draining into a riparian wetland and first-order stream at the USDA-ARS Beltsville Agricultural Research Center, Beltsville, MD are being studied with this protocol. The spatial location of some preferential flow pathways for chemicals exiting these agricultural watersheds to the neighboring ecosystems have been identified. Confirmation of the pathways is via examination of patterns in yield monitor data and remote sensing imagery.

Agriculture↗
PubMed1997

Mammography diffusion and trends in late-stage breast cancer: evaluating outcomes in a population.

The purpose of this study was to assess mammography diffusion in a population offered an organized breast cancer screening program, using intervals of 1-3 years, and to evaluate its effect on the late-stage cancer (tumors > or = 3 cm2) rates compared to rates in the surrounding community. We measured "ever-use" of mammography (1986-1992) among women enrollees of a consumer-controlled health care organization (n > or = 60,000/year; ages > or = 40), Group Health Cooperative of Puget Sound (GHC). Among these same women and the surrounding community (n = > or = 745,000/year), we measured late-stage cancer rates. Using unconditional logistic regression, we compared annual rates of ever-use among GHC women ages 40-49 and > or = 50 (1986-1992) and late-stage breast cancer (1983/84-1991/92) among all women. Among all GHC women ages 40 to 49, and 50 years of age and older, 67.4 and 82.8%, respectively, ever-used mammography by 1992. By 1992, approximately one-third of the mammograms among GHC women occurred in each of the three previous years. The rate of late-stage tumors declined significantly in the GHC and non-GHC populations among women 50 years of age and older (P < 0.001) but not among women ages 40 to 49. In conclusion, implementing a system of automated reminders was not sufficient to maximize mammography use in a population. Reductions in late-stage disease occurred among women ages > or = 50, even when regular" was not synonymous with "annual."

Adult↗
PubMed1992

Clinical practice and new technology: prostate-specific antigen (PSA).

In response to a marked increase in the use of an available test, Group Health Cooperative of Puget Sound (GHC) evaluated the use of prostatic specific antigen (PSA) as a screening test for prostate cancer. A project team reviewed the literature and determined that PSA did not meet GHC's criteria for screening. An implementation team then developed a comprehensive program to educate staff, facilitate practice change, measure outcomes and provide continuing feedback to physicians. These efforts are described and preliminary reports reported.

Decision Support Techniques↗
PubMed1984

The role of circulating immune complexes in the aetiology of polymorphic eruption of pregnancy.

Circulating immune complexes were measured in 35 patients with polymorphic eruption of pregnancy employing three different techniques. No significant abnormalities were detected by the C1q solid phase binding assay and polyethylene glycol precipitation of immunoglobulin G. However, using a solid phase polyclonal rheumatoid factor binding assay, which detects small immune complexes, we demonstrated a significant reduction in the level of circulating immune complexes during the acute stage of the eruption. We suggest that the leakage of small immune complexes through dilated upper dermal vessels may play a role in the aetiology of polymorphic eruption of pregnancy.

Antigen-Antibody Complex↗
PubMed1983

Clues to the aetiology and pathogenesis of herpes gestationis.

In a study of twenty-five patients with herpes gestationis we found that 80% possessed the HLA antigen DR3, which confers increased immune responsiveness and a predisposition to 'auto-immune disease'. In five patients the development of herpes gestationis coincided with a change in sexual partner, suggesting that the development of herpes gestationis may depend on exposure to an antigen derived from the father. This might share determinants with a component of the basement membrane zone of skin. Although anti-basement membrane zone antibodies are present in HG it is not clear whether they play a pathogenic role. The infrequency of neonatal involvement and the lack of correlation between immunofluorescence findings and clinical activity in our patients suggested that the antibodies might be a result of tissue damage rather than its cause. Two patients in our study were exceptional in that episodes of herpes gestationis were followed by normal pregnancies. In these patients the relationship of their DR antigens to those of the fetus may have been important in determining whether or not the pregnancy would be affected by herpes gestationis.

Child↗
PubMed1979

Maternal height and twinning.

Data on maternal height are presented for 307 pairs of newborn twins of known zygosity from Oxford and 267 pairs from Aberdeen and north-east Scotland. The results support the hypothesis that mothers of DZ twins are taller than those of MZ twins. Mothers of MZ twins resemble mothers of singletons in height, whereas mothers of DZ twins are taller.

Body Height↗
PubMed1978

Familial lichen planus. Another disease or a distinct people?

When lichen planus strikes families, a very rare happening, it is likely to afflict younger members, to erupt more acutely, extensively, and gravely, attacking also nails and mucous membranes, and to recur. Ten patients with familial lichen planus, two each from five distinct Caucasian families, the parents of whom were unrelated by birth, were found to be carrying HLA-B7 statistically more frequently than in the normal population or in those with the characteristic forms of lichen planus. We hint that their genotype might have rendered them susceptible to a pathogen that precipitated their disease.

Adolescent↗