PubMed Health⌕ Search

Biomedical subjects

A Bard

Publications and source records attributed to A Bard.

8 recordsLinked to original sources
PubMed1995

Microlithography by using neutral metastable atoms and self-assembled monolayers.

Lithography can be performed with beams of neutral atoms in metastable excited states to pattern self-assembled monolayers (SAMs) of alkanethiolates on gold. An estimated exposure of a SAM of dodecanethiolate (DDT) to 15 to 20 metastable argon atoms per DDT molecule damaged the SAM sufficiently to allow penetration of an aqueous solution of ferricyanide to the surface of the gold. This solution etched the gold and transformed the patterns in the SAMs into structures of gold; these structures had edge resolution of less than 100 nanometers. Regions of SAMs as large as 2 square centimeters were patterned by exposure to a beam of metastable argon atoms. These observations suggest that this system may be useful in new forms of micro- and nanolithography.

Argon↗
PubMed1991

Neurofibromatosis type 2: report of a family and review of current evaluation and treatment.

Significant advances during the past decade have greatly improved our understanding of neurofibromatosis type 2, a genetic disease which results in bilateral acoustic neuromas. The emergence of gadolinium-enhanced magnetic resonance imaging has allowed early detection of minute intracanalicular eighth-nerve tumors, less than 1 cm in diameter. Recombinant DNA studies have clarified the genetics that underlie neurofibromatosis type 2 and separate it from a variety of related conditions, such as von Recklinghausen's neurofibromatosis. Early diagnosis and surgical removal of these tumors may offer the only hope of preserving hearing and facial nerve function. A report of the evaluation and treatment of a family with multiple affected individuals will exemplify these conclusions.

Adolescent↗
PubMed1983

[Adenomatous lesions of the papilla in familial adenomatous rectocolic polyposis. Value of duodenoscopy].

When compared to the general population, individuals with Gardner's syndrome may have a 100- to 200-fold increased risk of developing periampullary carcinoma. This prospective work was undertaken in order to study the endoscopic aspects and to perform biopsies of the papilla in 9 patients (7 males, 2 females, aged 18-65 years) with familial polyposis coli or Gardner syndrome. In 4 cases the papilla was endoscopically grossly polypoid and biopsies showed adenomatous lesions. In 5 cases, the papilla appeared endoscopically normal; in 2 cases, the papilla appeared endoscopically normal; in 2 of these cases biopsies showed adenomatous proliferation; in the 3 other cases, the biopsies were normal. In 5 cases, there were adenomatous duodenal lesions outside the papilla. These results suggest that: a) adenomatous lesions of the papilla are frequent in familial polyposis coli and Gardner's syndrome; b) the endoscopic gross aspect of the papilla may be normal even when there are adenomatous lesions; c) adenomatous lesions of the papilla may be associated or not with adenomatous lesions of the 2nd duodenum; d) as the natural history of these lesions is not known and because of the risk of cancer of Vater's ampulla, it seems reasonable to perform routine duodenoscopies with biopsies in order to ensure early diagnosis of cancer.

Adenoma↗
PubMed1979

[Acute and chronic tuberculosis of the liver and hematopoietic system (author's transl)].

The authors report three cases of tuberculosis affecting the liver and hematopoietic system. The difficulty in diagnosing the chronic progressive forms of the disease and the severity of the acute forms is stressed. Liver biopsy is considered to be the most effective examination for confirming the nature of the disease. Acute and chronic forms can also be distinguished histologically, as the former produce nectotic lesions rich in tubercle bacillus but with only slight surrounding cellular reaction, while the latter lesions are productive and are rich in epithelioid histocytic cells.

Aged↗