Biomedical subjects

L M Lau

Publications and source records attributed to L M Lau.

7 recordsLinked to original sources

PubMed1995

Experience with a mixed semantic/syntactic parser.

The value of the computerized medical record is derived in part from the availability of medical information in a coded form accessible to manipulation by processes designed for automated decision support, medical research, and computer assistance in the management of health care delivery. To meet these needs medical reports captured and stored as natural language documents must be encoded. Below we discuss an ongoing formative process aimed at developing a natural language understanding system for chest x-ray reports. Comparative data showing the progress of this process is presented.

Hospital Information Systems↗

PubMed1994

A natural language understanding system combining syntactic and semantic techniques.

A large proportion of the medical record currently available in computerized medical information systems is in the form of free text reports. While the accessibility of this source of data is improved through inclusion in the computerized record, it remains unavailable for automated decision support, medical research, and management of medical delivery systems. Natural language understanding systems (NLUS) designed to encode free text reports represent one approach to making this information available for these uses. Below we describe an experimental NLUS designed to parse the reports of chest radiographs and store the clinical data extracted in a medical data base.

Bayes Theorem↗

PubMed1992

Performance of a diagnostic system (Iliad) as a tool for quality assurance.

Quality assurance improves health care through detection of quality problems and feedback to the care giver. Current review procedures employed by the Peer Review Organizations (PROs), however, appear to underdetect quality problems, particularly those arising from diagnostic errors. We studied the use of an expert diagnostic system, Iliad, to detect quality problems arising from diagnostic errors. One hundred cases were selected from among those Medicare cases reviewed by the Utah PRO (UPRO) and which contained diagnoses recognized by Iliad. Iliad flagged 28 cases out of the 100 as containing diagnostic errors, and a gold standard physician review confirmed quality problems in 17 cases (60.7%). The UPRO review found 28 cases with quality problems, mostly treatment and documentation errors. The quality problems detected by Iliad appeared to be more serious than those detected by the UPRO review. Among the six cases with quality problems detected by both the UPRO and the Iliad review, there was none for which the same quality problem was detected by the two procedures. The two review procedures were therefore complementary.

Adult↗

PubMed1991

Performance of a diagnostic system (Iliad) as a tool for quality assurance.

Quality Assurance improves health care through detection of quality problems and feedback to the care giver. Current review procedures employed by the Peer Review Organizations (PROs), however, appear to under-detect quality problems, particularly those arising from diagnostic errors. We studied the use of an expert diagnostic system, Iliad, to detect quality problems arising from diagnostic errors. 100 cases were selected from among those Medicare cases reviewed by the Utah PRO (UPRO) and which contained diagnoses recognized by Iliad. Iliad flagged 28 cases out of the 100 as containing diagnostic errors, and a gold standard physician review confirmed quality problems in 17 cases (60.7%). The UPRO review found 28 cases with quality problems, mostly treatment and documentation errors. The quality problems detected by Iliad appeared to be more serious than those detected by the UPRO review. Among the six cases with quality problems detected by both the UPRO and Iliad review, there was none for which the same quality problem was detected by the two procedures. The two review procedures were therefore complementary.

Diagnosis, Computer-Assisted↗

PubMed1991

Performance of a diagnostic system (Iliad) as a tool for quality assurance.

Quality Assurance improves health care through detection of quality problems and feedback to the care giver. Current review procedures employed by the Peer Review Organizations (PROs), however, appear to underdetect quality problems, particularly those arising from diagnostic errors. We studied the use of an expert diagnostic system, Iliad, to detect quality problems arising from diagnostic errors. 100 cases were selected from among those Medicare cases reviewed by the Utah PRO (UPRO) and which contained diagnoses recognized by Iliad. Iliad flagged 28 cases out of the 100 as containing diagnostic errors, and a gold standard physician review confirmed quality problems in 17 cases (60.7%). The UPRO review found 28 cases with quality problems, mostly treatment and documentation errors. The quality problems detected by Iliad appeared to be more serious than those detected by the UPRO review. Among the six cases with quality problems detected by both the UPRO and Iliad review, there was none for which the same quality problem was detected by the two procedures. The two review procedures were therefore complementary.

Diagnosis, Computer-Assisted↗

PubMed1990

Inability of polyglycolic acid mesh to inhibit immediate post-radical pelvic surgery adhesions.

The ability of a polyglycolic acid (PGA)-derived mesh to limit the formation of immediate postoperative pelvic adhesions after radical resection of the pelvic viscera and peritoneum was investigated. Twenty female canines underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, and infracolonic omentectomy. The entire peritoneum of the pelvis and lower abdomen also was removed. In ten animals, a single layer of PGA mesh, tailored to cover the deperitonealized area, was sutured in place. Reperitonealization was not performed in control animals. Four weeks after initial surgery, animals were reexplored and killed. Adhesions to the anterior abdominal wall and pelvis were quantified and graded: (Table: See Text) These data indicate that the placement of a PGA mesh induces significant pelvic adhesions and potentiates the formation of pelvic abscesses.

Animals↗

PubMedDate not supplied

Molecular genetic and morphological analyses of the African wild dog (Lycaon pictus).

African wild dog populations have declined precipitously during the last 100 years in eastern Africa. The possible causes of this decline include a reduction in prey abundance and habitat; disease; and loss of genetic variability accompanied by inbreeding depression. We examined the levels of genetic variability and distinctiveness among populations of African wild dogs using mitochondrial DNA (mtDNA) restriction site and sequence analyses and multivariate analysis of cranial and dental measurements. Our results indicate that the genetic variability of eastern African wild dog populations is comparable to that of southern Africa and similar to levels of variability found in other large canids. Southern and eastern populations of wild dogs show about 1% divergence in mtDNA sequence and form two monophyletic assemblages containing three mtDNA genotypes each. No genotypes are shared between the two regions. With one exception, all wild dogs examined from zoos had southern African genotypes. Morphological analysis supports the distinction of eastern and southern African wild dog populations, and we suggest they should be considered separate subspecies. An eastern African wild dog breeding program should be initiated to ensure preservation of the eastern African form and to slow the loss of genetic variability that, while not yet apparent, will inevitably occur if wild populations continue to decline. Finally, we examined the phylogenetic relationships of wild dogs to other wolf-like canids through analysis of 736 base pairs (bp) of cytochrome b sequence and showed wild dogs to belong to a phylogenetically distinct lineage of the wolf-like canids.

Africa, Eastern↗