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A Cohen

Publications and source records attributed to A Cohen.

At least 775 records · Page 43Linked to original sources
PubMed1984

A microcomputer-controlled system for stimulation and acquisition of evoked potentials.

A system, controlled by a microcomputer (LSI-11/23 with appropriate peripherals) for conducting evoked potential (EP) experiments, is described. In each experimental trial, a stimulus is applied and multichannel EEG is sampled, displayed, and stored in an output file. Any required length of pre- and poststimulus sampling periods is available. Stimuli are triggered by a human operator, aided by an on-line graphic display of sampled data. Automatic artifact monitoring is used for rejecting bad trials. Various stimulators may be used (simultaneously) and stimulus features (duration, power, number of pulses) may be changed in each trial. Lists of trial parameters, such as stimulus features and subject's response, are incorporated in the output file to facilitate cross-section analysis. The system was designed for the needs of pain EP research, but its flexibility and modularity make it useful in other areas of EP research.

Computers↗
PubMed1984

A single locus in the mouse encodes both myosin light chains 1 and 3, a second locus corresponds to a related pseudogene.

Two loci have been characterized in the mouse Mus musculus, which are homologous to the mRNAs encoding myosin light chains MLC1F and MLC3F, two proteins with a common -COOH terminal sequence. One of these loci is an intronless pseudogene, absent from the mouse species Mus spretus; alterations in its nucleotide sequence preclude it from generating a functional MLC1F or MLC3F. The other contains the genetic information for the two proteins. The part common to both proteins is encoded by five exons, which cover about 6.5 kb. Genetic information specific for the N-terminal sequences is encoded in four exons, at 3.5 and 14.3 kb for MLC1F, and 3.8 and 4.5 kb for MLC3F, upstream of the first common exon. Each 5' terminus has a TATA-like consensus sequence about 30 bases upstream of the cap site. The pseudogene is not genetically linked to the functional MLC1F/MLC3F locus in the genome of Mus musculus.

Amino Acid Sequence↗
PubMed1984

Local failure following curative resection of colonic adenocarcinoma.

A retrospective review of the medical records of 533 patients undergoing resection with curative intent of large bowel above the peritoneal reflection was undertaken to identify subsets of patients at high risk for local failure. The overall local failure rate was 102/533 (19%) with 32/102 patients having local failure only and 70/102 patients having concurrent local failure and distant metastases. Pathological confirmation of local failure was obtained in 79% of the cases and by surgical exploration in 75%. Overall local failure rates increased with advancing stage of disease. Tumors staged B3, C2 and C3 all had local failure rates in excess of 30%, whereas for Stage A, B1, B2 and C1 lesions, the incidence of local failure was less than 4%. Stage B2 tumors arising in high and low sigmoid and splenic and hepatic flexure had a moderate incidence of local failure (21%) compared to low incidence (5%) at all other sites. The majority of local and regional failures 84/102 (82%) occurred in tumor bed and adjacent soft tissues whereas only 18/102 (18%) local failures occurred in regional nodal groups. The overall local failure rate increased from 27% with one lymph node involved to 50% with greater than 5 lymph nodes involved. Patients with Stage B3, C2 and C3 colon tumors at all sites and selected B2 tumors have a high rate of local failure after surgical resection. The value of postoperative radiotherapy should be formally studied in these patients.

Adenocarcinoma↗
PubMed1984

The effect of nonhomologous DNA sequences on interplasmidic recombination.

The effect of nonhomologous DNA sequences at one or both sides of short genetic intervals on recombination within that interval was investigated, using an interplasmidic recombination system in Escherichia coli K-12. The recombining plasmids were derivatives of pBR322 and pACYC184, which share a 1330-nucleotide sequence that includes the tet gene. The genetic interval was defined by the HindIII and BamHI or BamHI and the SalI restriction endonuclease sites of this gene. The substantial differences between recombination frequencies measured within intervals bracketed or bounded on one side by major nonhomologies suggests that, in this system, strand exchange is polar and is blocked by major nonhomologies. This conclusion is substantiated by results of three-factor crosses and by structural analysis of recombination products. Results of two-factor crosses in recA genetic background and structural analysis of recombination products suggest that strand exchange occurs in the absence of a functional recA gene. "Opening" a bracketed BamHI-SalI genetic interval of the tet gene, at the SalI site, by substituting a major insertion with a short deletion, results in an increase in recombination frequency, within this genetic interval, which is greater than expected on the basis of the ratio of the length of homology on the two sides of the SalI site. This observation suggests that a genetic element that may affect rate of recombination initiation, polarity of strand exchange, template specificity in mismatch repair or more than one of these events may be present on the outer side of the SalI site of the tet gene.

Base Sequence↗
PubMed1984

Descartes, consciousness and depersonalization: viewing the history of philosophy from a Strausian perspective.

This paper develops particular Strausian -like themes on the formation and structure of the Cartesian problematic. Particularly, my interest is to link the Cartesian 'invention' of consciousness (or 'the mental') in the philosophy of mind with the issues of representation and 'the problem of the external world' in epistemology. The Cartesian novelty becomes clear by comparing Cartesian scepticism with Greek classical scepticism . I end with some speculative clinical (i.e., psychiatric) suggestions on possible roots of the Cartesian invention.

Consciousness↗
PubMed1984

Osler's nodes, pseudoaneurysm formation, and sepsis complicating percutaneous radial artery cannulation.

Percutaneous arterial cannulation is useful for hemodynamic monitoring and frequent arterial blood gas determinations in selected intensive care patients. However, this procedure is not without risk. We report a case of localized Osler node formation, distal to a radial artery catheter, associated with sepsis, pseudoaneurysm formation, and thrombosis at the site of catheterization. Complications of this technique require aggressive medical and, in selected cases, surgical intervention.

Adult↗
PubMed1984

Fulminant hepatic failure complicating metastatic breast carcinoma.

A 27-year-old woman died in fulminant hepatic failure caused by metastatic carcinoma of the breast. At autopsy the liver looked grossly normal but was diffusely infiltrated by malignant tumor cells with resultant massive necrosis of liver parenchyma. Breast carcinoma has been the most common cause of this syndrome.

Acute Disease↗
PubMed1984

Immunological characterisation of rubella virion polypeptides.

Antibodies specific for rubella virion polypeptide, VPI, secreted by clones of hybridoma cells or produced in rabbits in response to specific antigenic stimulation, located determinants for haemagglutination inhibiting (HI) and neutralising (Nt) antibodies on this envelope component.

Antibodies, Viral↗
PubMed1984

Depletion of excessive liver iron stores with desferrioxamine.

To determine the therapeutic effect of long-term, intensive iron chelation therapy, we studied liver iron content and histology in four children with thalassaemia major during 52-83 months of intensive therapy with desferrioxamine. The initial biopsies obtained prior to or within 21 months after beginning chelation therapy had Grade IV iron staining, with heavy iron deposition present in parenchymal and reticuloendothelial cells. Subsequent biopsies, obtained when serum ferritin levels had fallen to 71-246 micrograms/l, contained Grade 0 or Grade I stainable iron. Little or no iron was present in parenchymal or reticuloendothelial cells. The liver iron concentration, measured by magnetic susceptibility, returned to normal or nearly normal levels. Hepatic fibrosis did not progress during treatment with desferrioxamine. These findings demonstrate that intensive and sustained chelation therapy with desferrioxamine will remove excessive liver iron and preserve hepatocellular structure.

Adolescent↗