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Biomedical subjects

D Hines

Publications and source records attributed to D Hines.

18 recordsLinked to original sources
PubMed1992

Blood donation and transfusion practices: the 1990 American Association of Blood Banks Institutional Membership Questionnaire.

Responses to the 1990 American Association of Blood Banks (AABB) Institutional Membership Questionnaire were submitted by 2126 regional blood centers, hospital-based blood banks, and transfusion facilities. Data from 2117 of these facilities were considered to be valid. The questionnaire included information on blood donor demographics, number of units collected, and collection procedures; services performed; usage of blood components; and transfusion-transmitted diseases reported during 1989. Institutional members collected 7.4 million whole blood units, of which 90.8 percent were donated for allogeneic use, 6.0 percent were donated for autologous use, and 3.2 percent were donated for directed use. Approximately 630,546 allogeneic and directed-use blood donors were deferred, most often for low hemoglobin or hematocrit values. Approximately 225,205 full allogeneic and directed-donor units were discarded, primarily for elevated alanine aminotransferase levels or the presence of hepatitis B core antibody. The 14.3 million transfused components included 56.7 percent red cell-containing components, 27.4 percent platelets, 11 percent fresh-frozen plasma, and 4.8 percent cryoprecipitate. Institutional members reported 1397 cases of transfusion-associated hepatitis. In this group, 921 patients were tested for hepatitis B surface antigen after the transfusion; 339 (36.8%) were found to be hepatitis B surface antigen positive. The AABB Institutional Questionnaire results provide recent data on blood donor and transfusion-related activities that are vital to the evaluation of current transfusion medicine practices.

Acquired Immunodeficiency Syndrome↗
PubMed1978

Task difficulty and visual similarity increase a distractor's effects on random shapes.

Recognition of random shapes followed by a visual distractor is altered by the type of distractor and whether the distractor needs to be attended. Three experiments tested which characteristics modify a visual distractor's effect on random target shapes presented for 75 to 150 msec. Exp. 1 showed that increasing the number of digits to be remembered (1, 3, or 8) increased the effectiveness of digits as distractors. Exeir effect as visual distractors for random target shapes. Random shapes were highly effective as distractors, while pictures of faces or comples colored pictures had a relatively small effect. In Exp. 3 decreasing the presentation time for novel visual distractors decreased recognition of the distractors but not of random target shapes. However, adding a three-digit distractor after the novel visual distractor did decrease recognition of target shapes. Exps. 2 and 3 showed that the order of the recognition tests of the target and distracting stimuli altered target recognition if and only if subjects did know which was to be reported first. These experiments indicate that the effect of a visual distractor depends on both the extent to which it is allotted attention and its visual similarity to the target stimulus.

Attention↗
PubMed1977

Effects of amphetamine and nembutal on social exploration in the Mongolian gerbil.

Male Mongolian gerbils were injected intraperitoneally with amphetamine, nembutal, or saline and placed in a preference chamber one side of which contained a female gerbil. Amphetamine significantly decreased amount of time in contact with the females. Although the amphetamine effect held for both novel and familiar females, it was more marked for novel than for familiar females.

Animals↗
PubMed1977

Differences in tachistoscopic recognition between abstract and concrete words as a function of visual half-field and frequency.

This experiment demonstrated that the greater right visual half-field (VHF) superiority for abstract words than for concrete words reported in two previous studies generalized to an independent, larger sample of abstract and concrete nouns. In addition, degree of concreteness was found to be positively related to overall recognition, with high concrete words averaging 38% correct, moderate concrete words averaging 30% correct, and abstract words averaging 20% correct. Analyses of ratio scores indicated that high frequency abstract words showed a significantly larger right VHF asymmetry than high frequency moderately concrete words or high frequency high concrete words. Groups of abstract, moderately concrete and high concrete words were also matched on right VHF recognition, to evaluate whether differences in VHF asymmetry were secondary to the differences in overall recognition. A significant interaction between VHF and word class was found, again indicating larger right VHF superiority for the abstract words. The data are consistent with previous suggestions that some left VHF concrete words are recongized by the right hemisphere.

Dominance, Cerebral↗
PubMed1977

Recognition of random shapes followed at varying delays by attended or unattended shapes, digits, and line grids.

Three experiments evaluated the effect of poststimulus distractor characteristics in altering recognition of random shapes. Experiment 1 demonstrated that when 150 msec or 300 msec were allowed for processing the initial shape stimulus, recognition was lowered only when it was followed by an attended shape or digit distractor. Unattended shapes, digits, and line grids and attended line grids left recognition essentially perfect. Attended shapes lowered recognition more than attended digits. Experiment 2 found that attended shapes, digits, and line grids all masked random shapes when presented immediately upon offset of a random shape displayed for 50 msec. As processing time increased, digit distractors became less effective than shape distractors, while line grids lost all effect. The shape distractors lowered recognition up to 1,200 msec. Experiment 3 showed that the larger recognition loss produced by the shape distractor than by the digit distractor could not be attributed to differences in response procedure. It was suggested that memory for random shapes moves from brief visual storage to a limited capacity visual short-term memory. Attended shape distractors may eliminate the stimulus shape from visual short-term memory thus preventing long-term storage.

Attention↗
PubMed1976

Recall of letters from the left and right visual half-fields under unilater and bilateral presentation.

Bilateral presentation in the visual half-field greatly increases superiority of the right visual half-field in tachistoscopic recognition of words when fixation is controlled using a center digit. Two experiments explored left-right asymmetry with bilateral presentation on a visual half-field short-term memory task, with fixation controlled by a sequence of letters at fixation. A total of 40 subjects served in the two experiments, which compared recall under unilateral versus bilateral presentation to the visual half-field. Bilateral presentation increased over-all recall from the last serial position but did not alter asymmetry of the visual half-field. As in previous experiments, the superiority of the right visual half-field was greatest from the initial serial positions. It was concluded that asymmetry of the visual half-field on this recall task with controlled fixation depends primarily on masking and short-term memory but is independent of unilateral-bilateral presentation.

Eidetic Imagery↗
PubMed1976

Hitler: a neurohistorical formulation.

It is hypothesized that Adolf Hitler suffered from a constitutional left-side weakness that allowed his cerebral hemisphere to exert a strong influence on his thought and behavior. Physical characteristics such as trembling of the left extremities, lack of a left testicle, and tendency to exhibit leftward eye movements are interpreted as supportive of the hypothesis. Right hemisphere dominance is consistent with a number of Hitler's personal traits such as praise of the irrational, automatic speech, auditory hallucinations, hypochondriasis, uncontrolled rages, and spatial and musical interests. Right hemisphere dominated thought may also have formed a basis for his two basic political policies: Lebensraum and anti-Semitism.

Dominance, Cerebral↗
PubMed1975

Creativity and cortical activation during creative, intellectual and EEG feedback tasks.

Thirty-two male subjects were divided into four groups based on their performance on the remote associates test and alternate uses test, two measures of creativity. Right EEG alpha presence was monitored under basal conditions, while subjects took tests of creativity and intelligence, and while they attempted to enhance and suppress the amount of alpha in a feedback situation. High scorers on the alternate uses test operated at a high percentage of basal alpha during all tests while high scorers on the remote associates test showed differential amounts of alpha presence across tests, with the highest percentage of basal alpha during tests of creativity and the lowest percentage during an intellectual test. Both high creative groups tended to show increases in amount of alpha across trials when trying to suppress alpha as well as when trying to enhance it, but did not differ in overall control from the low creative groups.

Alpha Rhythm↗
PubMed1975

Independent functioning of the two cerebral hemispheres for recognizing bilaterally presented tachistoscopic visual-half-field stimuli.

Bilateral tachistoscopic presentation of verbal stimuli produces a significantly larger right visual half-field (VHF) superiority than does unilateral presentation, when fixation is controlled by a center digit. This experiment tested whether the increased asymmetry was due to (a) subjects attending the right VHF and ignoring the left VHF or (b) interference between the hemispheres due to competition for the left hemisphere language areas. Words, shaptes, and pictures of faces were presented bilaterally to each VHF, with fixation controlled by a center digit. In three conditions, the same type of stimuli was presented in each VHF (e.g., a word in both the left and right VHF). In two conditions words were presented to one VHF and nonverbal stimuli to the opposite VHF (words paired with words and words paired with faces). It was found that the stimulus pairings did not affect VHF asymmetry for any stimulus. Words showed a large right VHF superiority in all conditions. Shapes showed a significantly smaller right VHF superiority in all conditions. Faces showed no VHF asymmetry in any condition. It was concluded that attentional factors were not important since shapes or faces could be recognized accurately from the left VHF without lowering verbal recognition from the right VHF. Thus the low recognition accuracy from the left VHF is specific for verbal stimuli rather than attentional. The interference hypothesis was also not supported since all the right VHF stimuli (words, shapes, or faces) were associated with low recognition of words from the left VHF. It was suggested instead that VHF asymmetry under unilateral and bilateral presentation reflect two different mechanisms. Under conditions of unilateral presentation, VHF asymmetries are caused by loss of information when any given stimulus must cross the callosum to reach the hemisphere specialized for its processing. However, with bilateral VHF presentation and fixation control, the two hemispheres act as independent channels for information processing. Under this condition, each hemisphere recognized the stimulus from its contralateral VHF. Thus the large right VHF superiority for words with bilateral presentation reflects the superior ability of the left hemisphere for verbal recognition.

Attention↗
PubMed1975

Effect of suture materials on healing skin wounds.

A systematic comparison has been made of six suture materials used as subcuticular closure of abdominal incisions in dogs. The effect on wound healing was measured by mechanical, biochemical, and histologic methods. No difference was demonstrated in wound breading strength among wounds closed with different suture materials up to 28 days postoperatively. At 70 days, wounds sutured with nonabsorbable sutures were weaker than those closed with absorbable sutures, but this difference probably was due to a much higher incidence of infection in wounds closed with nonabsorbable sutures. It was our observation that monofilament sutures were superior to multifilament sutures with regard to the incidence of wound infection. By five days, the rate of collagen synthesis in wounds was increased over that of normal skin and remained elevated throughout the 120 day observation period. Suture material had no effect on collagen synthesis. The rate of noncollagenous protein synthesis in the wound was not altered throughout the entire observation period and did not differ from that measured in normal skin. Catgut, both plain and chromic, produced only a mild cellular reaction in dogs after 21 days as contrasted with the intense inflammatory reaction reported by others in rats and rabbits. We observed neither plain nor chromic catgut was absorbed rapidly in dogs; intact sutures were frequently observed at 120 days. Polyglactin, a synthetic absorbable suture, produced a moderate tissue reaction and uniformly disappeared between the twenty-eighth and seventieth days. Silk and Mersilene showed the highest rate of wound infection and the most intense and prolonged tissue reaction. Prolene, a monofilament suture, produced only a mild to moderate tissue reaction. These results taken in conjunction with those of other investigators suggest a marked species difference in the reaction to suture materials, particularly catgut, and suggest caution in transferring these observations to human beings.

Animals↗
PubMed1975

The effect of suture materials on healing wounds of the bladder.

The healing pattern of bladder tissue and its response to various suture materials were studied and compared with data reported previously on skin, stomach and colon wounds. Tensile strength, biochemical data and histologic reactions were used as parameters of wound healing measurement. The healing pattern of urinary bladder wounds resembles that observed for stomach and colon. However, wounds of the urinary bladder wall regain strength equal to unwounded bladder wall within 21 days, whereas wounds of stomach and colon do not achieve more than 70 per cent of unwounded tissue strength after 120 days. The rate of collagen synthesis in bladder wounds reaches a peak at five days and returns to that of normal unwounded tissue by 70 days. Colon and stomach wounds, on the other hand, showed elevated rates of collagen synthesis even at 120 days. As with colon and stomach, absorbable sutures appear to lower the strength of both the wound and unwounded tissue. However, in stomach and colon this effect is only observed during the first 21 days of healing; in the bladder it persists throughout the 120 day observation period. No histologic evidence of smooth muscle regeneration was seen in bladder wounds. Noncollagenous protein synthesis was not increased in the wound, also suggesting smooth muscle regeneration does not occur. Silk and Mersilene sutures produced the greatest tissue reaction; if the sutures were exposed in the lumen of the bladder, stone formation was observed. This was not observed with monofilament polypropylene sutures. Plain catgut produced the least tissue reaction, but both plain aions comparable with chromic catgut but were regularly absorbed between 28 and 70 days. Since the bladder is well healed by 21 days, polyglactin-910 may be an ideal suture for use in the bladder.

Absorption↗
PubMed1975

Effect of suture materials on healing wounds of the stomach and colon.

Wound healing in the stomach and colon of mongrel dogs was studied using physical, histologic and chemical techniques to evaluate effects of various suture materials on the healing pattern and to compare visceral wounds with skin wounds. The general pattern of healing for stomach and colon wounds is the same in rats, rabbits and dogs. However, the extent of healing, the percentage of strength of normal tissue attained by the wound, is less in the dog than in the rat or rabbit. Prolene and plain and chromic catgut produce the least and silk produces the greatest cellular reaction in the stomach and colon. We believe the effect of absorbable sutures on strength of stomach and colon wounds, while statistically significant, is not of any great clinical significance except perhaps in severely debilitated patients. A trial of Prolene sutures for anastomotic closure would seem indicated. The healing of stomach and colon wounds differs from the pattern observed for skin wounds. Breaking strength increases rapidly for 14 to 21 days postwounding and then does not change significantly. The wounds are metabolically more active than skin wounds since the rate of collagen synthesis is markedly elevated even after 120 days and the rate of noncollagenous protein synthesis is twice as great in the wound as it is in normal tissue. Colon and stomach wounds closed with absorbable sutures are weaker at 14 through 28 days than similar wounds closed with nonabsorbable sutures. Yet, when strength of wound is expressed as a percentage of strength of unwounded tissue, there is no difference between wounds blosed with absorbable or nonabsorbable sutures. Thus, it would appear that there is a general diminution of the strength of normal stomach and colon wall up to 6 centimeters from wounds which have been closed with absorbable sutures.

Animals↗
PubMed1975

Immediate and delayed recognition of sequentially presented random shapes.

Two experiments tested whether short-term memory accounts for the recency effect observed with rapid sequential presentation of nonverbal stimuli. Four random shapes were presented sequentially (with no interstimulus interval) on each trial at rates of 150 msec, 250 msec, 500 msec, and 1,000 msec per stimulus. Subsequent recognition varied positively with exposure duration, ranging from 57% at 150 msec to 77% at 1,000 msec. Two serial position effects were observed: a slight decrease in recognition accuracy for the first stimulus in each sequence and a large increase in recognition for the last stimulus in each sequence. The recency effect was not altered by an intervening 30-sec delay, an intervening 30-sec copying task, or an intervening 30-sec copying and counting task. Since neither visual nor verbal distractors altered recognition accuracy, it was suggested that all shapes were processed directly into long-term memory storage. It also was hypothesized that long-term storage of a nonverbal stimulus requires identification of a distinctive feature of the stimulus and that this process may continue for a brief period after actual stimulus offset.

Form Perception↗