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M D Walker

Publications and source records attributed to M D Walker.

139 records · Page 8Linked to original sources
PubMedDate not supplied

Cell-specific expression controlled by the 5'-flanking region of insulin and chymotrypsin genes.

DNA sequences containing the 5'-flanking regions of the insulin and chymotrypsin genes were linked to the coding sequence of the chloramphenicol acetyltransferase (CAT) gene. The insulin gene recombinant elicits preferential expression of CAT activity when introduced into cells producing insulin; similarly, the chymotrypsin gene recombinant elicits preferential expression in chymotrypsin-producing cells. Sequences located upstream of previously defined transcriptional control elements are essential for efficient expression in both cases.

Acetyltransferases↗
PubMedDate not supplied

Analysis of pesticide residues in hops and their extraction by liquid CO2 during the production of hop extracts.

A method has been developed for analysing pesticide residues in whole hops, hop pellets and hop extracts by GC-MS. Five batches of hop pellets containing nine different pesticides (triadimefon, dicofol, mephosfolan, bupirimate, cyhalothrin, tetradifon, endosulfan, pyrazophos and total bisdithiocarbamates) were extracted with liquid CO2. Pesticide concentrations in the original hop pellets and the extracts were determined. The pesticides were concentrated by the extraction process (concentration factor 1.3-8.3), except for the bisdithiocarbamates, which were not extracted. When the same amount of bitterness was added into the brewing process using liquid CO2 extract as opposed to hop pellets, for most of the pesticides proportionately less pesticide was added. However, for two pesticides (dicofol and triadimefon) corrected residue levels were similar to, or in some cases slightly higher than, those in hop pellets.

Beer↗
PubMedDate not supplied

Community Hospital-based Stroke Programs: North Carolina, Oregon, and New York. I: Goals, objectives, and data collection procedures.

In order to assess the impact of variations in stroke care on outcomes, and to make geographic comparisons, the three Community Hospital-Based Stroke Programs in North Carolina, Oregon, and New York, aggregated their data on 4,132 hospitalized stroke patients. Complete demographic data or "Major Profile" were obtained on 2,390 (57.8%) of the 4,132 stroke patients. This includes those patients on whom informed patient and physician consents were obtained during the hospitalization. Of the major profile patients, 1,490 (62.3%) were followed for periods up to one year, 502 (21.0%) were lost to followup and 398 (16.6%) died within the one year followup period. Incomplete demographic data or "Minor Profile" were observed on 1,742 (42.1%) of the 4,132 patients. Minor profile includes those who died before comprehensive interviews were completed or those for whom informed consent for an interview could not be obtained. Of the minor profile group, 813 (46.7%) died in hospital, and 929 (53.3%) were alive when discharged from the hospital. This paper, which describes the programs, data collection procedures, and study cases, also highlights specific issues on stroke diagnosis, risk factors associated with stroke, and the influence of interventions on stroke outcomes. We conclude that: 1) the merging of data on hospitalized stroke cases from rural and urban hospitals in geographically distinct regions can be used in the study of stroke diagnosis, the use of diagnostic tests, and the effect of interventions on stroke outcomes; and 2) these data are consistent with the hypothesis that part of the national decline in mortality from stroke is due to a decline in stroke severity.

Adult↗
PubMedDate not supplied

Community Hospital-based Stroke Programs: North Carolina, Oregon, and New York. II: Description of study population.

The three Community Hospital-based Stroke Programs collected data on 4132 stroke patients admitted to acute care hospitals during 1979 and 1980. White female stroke patients were older than the white male, nonwhite female and nonwhite male stroke patients. Nearly one-fourth (23%) of stroke patients were employed at the time of the event. Most (77%) of the patients were hospitalized for first stroke episodes. Eighty-three percent of the patients had at least one of the four major risk factors for stroke, namely, hypertension, diabetes, transient ischemic attacks and cardiac disease. Half (49%) of the patients were alert at the time of admission. The three diagnostic categories included infarction (60%), stroke not otherwise specified (30%) and hemorrhage (10%). Fourteen days was the median length of hospitalization; 50% of the stroke patients were discharged to a home setting, 31% were institutionalized and 19% died while in the hospital. The mean Barthel Index score for 2400 patients at the time of discharge was 61.8 (normal is 100). Of those patients who were working at the time of the stroke, 22% returned to work. In comparison to the patients in the National Survey of Stroke, patients in this Study were less severe at the time of admission (49% of patients in the National Survey of Stroke were stuporous or comatose compared to 21% of the patients in the current Study). The inhospital fatality was 30.7% in the National Survey of Stroke, and 19.7% in the current Study.

Activities of Daily Living↗
PubMedDate not supplied

Community Hospital-based Stroke Programs: North Carolina, Oregon, and New York. III. Factors influencing survival after stroke: proportional hazards analysis of 4219 patients.

The possible effect of age, race, sex, consciousness upon admission, geographic location, and history of selected risk factors on the survival after stroke due to infarction or hemorrhage was determined using proportional hazards analysis (Cox regression). For each diagnostic category the most significant prognostic factor was consciousness upon admission. Increasing age, cardiac disease, or previous stroke also decreased the survival time of patients with infarctions. For patients with cerebral hemorrhage, no other variable was significant after control for consciousness level.

Adult↗