William C. Black

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BACKGROUND The aggressive and heterogeneous nature of lung cancer has thwarted efforts to reduce mortality from this cancer through the use of screening. The advent of low-dose helical computed tomography (CT) altered the landscape of lung-cancer screening, with studies indicating that low-dose CT detects many tumors at early stages. The National Lung(More)
Ticks are parasitiform mites that are obligate hematophagous ectoparasites of amphibians, reptiles, birds, and mammals. A phylogeny for tick families, subfamilies, and genera has been described based on morphological characters, life histories, and host associations. To test the existing phylogeny, we sequenced approximately 460 bp from the 3' end of the(More)
Pyrethroids are commonly used as mosquito adulticides and evolution of resistance to these compounds is a major threat to public health. 'Knockdown resistance' to pyrethroids (kdr) is frequently caused by nonsynonymous mutations in the voltage-gated sodium channel transmembrane protein (para) that reduce pyrethroid binding. Early detection of kdr is(More)
A Histology Activity Index has been developed which generates a numerical score for liver biopsy specimens obtained from patients with asymptomatic chronic active hepatitis. Biopsies are graded in four categories: periportal necrosis, intralobular necrosis, portal inflammation, and fibrosis. Under code, three pathologists and three hepatologists evaluated(More)
Little epidemiologic data are available on the occurrence of interstitial lung diseases (ILDs) in the general population. To describe the prevalence and incidence of ILDs a population-based registry of patients with ILDs was established in Bernalillo County, New Mexico in October 1988. All patients 18 yr of age and older who had a clinical diagnosis of an(More)
This article summarizes the phenomenon of cancer overdiagnosis-the diagnosis of a "cancer" that would otherwise not go on to cause symptoms or death. We describe the two prerequisites for cancer overdiagnosis to occur: the existence of a silent disease reservoir and activities leading to its detection (particularly cancer screening). We estimated the(More)
RAPD-PCR polymorphisms at 57 presumptive loci were used to examine the breeding structure of the mosquito Aedes aegypti in Puerto Rico. Mosquitoes were sampled from 16 locations in six cities and samples were located in a nested spatial design to examine local patterns of gene flow. Allele frequencies were estimated assuming (1) that genomic regions(More)
Genome sizes and the organization of repetitive DNA were determined in the hard ticks Ixodes scapularis and Boophilus microplus using reassociation kinetics. The I. scapularis genome contains approximately 2.15 pg (2.1x10(3) Mbp) of DNA and consists of no foldback (FB), 27% highly repetitive (HR), 39% moderately repetitive (MR), and 34% unique DNA. The B.(More)
The entire mitochondrial genome was sequenced in a prostriate tick, Ixodes hexagonus, and a metastriate tick, Rhipicephalus sanguineus. Both genomes encode 22 tRNAs, 13 proteins, and two ribosomal RNAs. Prostriate ticks are basal members of Ixodidae and have the same gene order as Limulus polyphemus. In contrast, in R. sanguineus, a block of genes encoding(More)
New techniques have recently been described that employ the polymerase chain reaction (PCR) to amplify arbitrary regions of a genome using a single primer. The techniques reveal polymorphisms in insect taxa that lack allozyme variation and, for the first time, permit genetic polymorphisms to be rapidly analysed in small arthropods (e.g. mites, endoparasitic(More)