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Biomedical subjects

R Cohen

Publications and source records attributed to R Cohen.

At least 595 records · Page 33Linked to original sources
PubMed1977

Plasma high-density lipoprotein cholesterol level. Influence of risk factor intervention.

Determinants of circulating high density lipoproteins (HDL) were sought in 301 men studied during a year of participation in a coronary prevention program. Mean plasma HDL-cholesterol concentration rose by 2.8 mg/dl (6%) in the group receiving multifactor intervention, but the change did not differ significantly from that in the comparison group. Larger changes in both directions were seen in many individuals. Multiple regression analysis of these changes indicates that increased plasma HDL levels occur when plasma triglyceride level is decreased, cigarette smoking is reduced, and habitual alcohol intake is increased. Increases in the concentration of HDL-cholesterol also tended to accompany adherence to the fat-controlled diet, reduction in LDL-cholesterol level, and loss of body weight. Conventional coronary prevention programs are unlikely to have an adverse influence on this new, risk-lowering factor.

Adult↗
PubMed1977

The conceptual structure of aphasic and schizophrenic patients in a nonverbal sorting task.

Hierarchical and overlapping cluster methods were applied to the sortings of aphasic, nonaphasic brain-damaged, schizophrenic, and normal subjects presented with 30 pictures of animals. The hierarchical structure solutions were most diffuse for the groups of the schizophrenics and the fluent aphasics'. The structure for the nonfluent aphasics showed more clarity, but was also deviant from the structures of the normals and the brain-damaged without aphasia. Fluent aphasics but not nonfluent aphasics tended to sort pictures which they could not name into smaller groups. For the nonfluent aphasics, there was a significant correlation between the commonality of the sortings and the severity of aphasic disturbances as measured by the Token Test. The relationship between conceptual disorganization and language impairment seems to be functionally different for fluent and nonfluent aphasics.

Adolescent↗
PubMed1977

Validity of the Sklar Aphasia Scale.

A German version of the Sklar Aphasia Scale (SAS) was administered to groups of fluent aphasics, nonfluent aphasics, and three control groups (brain-damaged patients without aphasia, schizophrenics, and normal subjects). The SAS discriminated fluent and nonfluent aphasics from schizophrenic brain-damaged, and normal control subjects with a high level of confidence; 91.8% of the aphasic and 81.5% of the brain-damaged patients without aphasia were correctly classified. However, the SAS did not discriminate between fluent and nonfluent aphasics. A factor analysis, which also included the subtests of the Token Test and eight other variables, showed the SAS and the Token Test to load mainly on the same general factor, which represents the severity of language disorders or the impairment of those left-hemisphere functions that might be basic to language. Subtests II and IV of the SAS also had loadings on a memory factor, but none of the subtests had variance on the third factor which represented the sensory-motor or fluency/nonfluencey dimension.

Aphasia↗
PubMed1977

Motivations for studying dentistry among first-year dental students.

Reasons for choosing dentistry as a profession were analysed among first-year dental students at the University of Toronto. The motivations of various sub-groups were also examined. It was found that an extrinsic motivation, financial rewards, was the most widespread, although the other widely chosen motivations referred mainly to intrinsic aspects of the profession such as working with and for people, stimulating work, and being autonomous. Cross-tabulation analysis and mutli-variate analysis of the motivations of various socio-demographic sub-groups were carried out. Three sub-groups showed more extrinsic orientations than the class as a whole: those of "other" religious preference; students feeling different from their classmates; and those from medium-sized towns. The most intrinsically oriented groups were: older students; those high in SES; and Jewish students.

Career Choice↗
PubMed1977

Pyridoxal-5-phosphate-resistant sideroblastic anaemia with trisomy 8 mosaicism in the bone marrow.

A patient with sideroblastic anaemia manifested a trisomic condition for chromosome number 8 in 75% of his bone marrow cells. Cytogenetic studies of peripheral lymphocytes demonstrated a normal male karyotype. The anaemia was resistant to treatment with pyridoxal-5-phosphate; this is in contradiction with the response achieved in some patients with the primary acquired form of sideroblastic anaemia.

Adult↗
PubMed1977

Use of 1alpha-hydroxycholecalciferol in the prevention of bovine parturient paresis.

A synthetic biologically active derivative of vitamin D (350 microgram of 1alpha-hydroxycholecalciferol [1alpha(OH)CC]) was injected into 2 nonlactating 7-year-old Israeli-Friesian cows. Plasma calcium values increased after 24 hours, peaked at 48 hours, and returned to base-line values 120 hours after injection. An injection of 350 microgram of 1alpha(OH)CC was given to 23 parturient-paresis-prone Israeli-Friesian cows from 7 days to 6 hours prepartum; 13 cows were injected once, 6 were injected twice, and 4 were injected 3 times, all at 48-hour intervals. Parturient-paresis-prone cows (n = 23) of the same breed were used as controls. Within 0 to 36 hours postpartum, plasma calcium concentrations were found to be higher in cows injected with 1alpha(OH)CC than in the control cows. The increase was highly significant (P less than 0.01) in cows injected at least twice. None of the cows injected with 1alpha(OH)CC, within 72 to 24 hours prior to calving developed parturient paresis; but 9 of 23 control cows developed parturient paresis. Prior to calving, none of the injected cows developed hypercalcemia and there was no local or systemic clinically detectable signs of toxiosis. When given at the right time prepartum, 1alpha(OH)CC is considered to be an improvement over previous methods of preventing bovine parturient paresis.

Animals↗
PubMed1976

Restricted associations of aphasics and schizophrenics.

Matched groups (N = 25) of fluent and nonfluent aphasics, brain-damaged and normal controls as well as schizophrenics were requested to name (1) as many animals and (2) as many things that are typically yellow as possible within 5 min. The main results of Gloning & Müller (1972) as to smaller numbers of correct responses, higher percentages of repetitions, shorter association clusters, and higher popularity in aphasics could be replicated for animal task. Comparing the data from both tasks for fluent and nonfluent aphasics with the various control groups led to considerable doubts as to what extent these results follow directly from quantitative differences in verbal output or have to be interpreted as qualitative differences in memory storage, retrieval, and self-editing processes.

Adult↗
PubMed1976

MaD, an automated precise analytical ultracentrifuge scanner system.

The various hardware components of this scanning system, a mechanical split-beam scanner with its photomultiplier measuring slit, minimum analog electronics and an important digital part (computer, interface), are intimately interwoven by an elaborate software. A high degree of automation and sophistication is thus reached. On the one hand, all the photoelectrons coming from each light pulse are integrated. The result, after conversion to digital form enters the computer; a high precision is thus reached: 10(-5) absorbance unit (A.U.) under very favorable conditions, and 10(-4) A.U. for conventional sedimentation studies. On the other hand, during its motion along the image, the precise slit position is permanently known by the system: the sector image is thus segmented into precisely defined zones, inside which the average absorbancies are determined, punched, plotted and printed. New and very useful utilizations and improvements of analytical ultracentrifugation are now possible: the fixed radius mode, permits precise s determination by following the radial dilution; s can be precisely measured by time difference curves even when the solution absorbancy is comparable to the base line variations (0.01 A.U.); round trip analyses permit very long analyses without the absorbancies distributions distorsions due to very long one-way scans during sedimentations runs; reductions of the effect of the stray light by a factor of ten. This system has been in routine use for four years.

Autoanalysis↗
PubMed1976

Aphasic disorders in matching tasks involving conceptual analysis and covert naming.

Aphasic, non-aphasic brain-damaged, schizophrenic and normal Ss were required to select which of two pictures in each item was indicated by a third picture. The latter was related to the referent not through direct associations but only through a mediator: a homonym -- the name for clue and referent --, a situational association, or a perceptual feature common to both. The availability of these mediators was to be tested. Aphasics were as good as normals when the task could be solved via situational associations (e.g. guitar/violin -- bullfight; mediator: "Spain"). They showed poorer performance than all the control-groups not only when the solution depended on the availability of a word but also when it was necessary to identify analytically a perceptual feature characteristic for clue and referent (e.g. swan/turkey -- snowman; mediator: "white"). This result is seen as possibly corresponding to the specific deficiency of both non-fluent and fluent aphasics in the Token Test which might be characteristic of left hemisphere dysfunctions in the analytical decomposition into separate features of what presents itself perceptually and experientally as a unit or Gestalt.

Adult↗