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Wilson BA. Interferon beta for treatment of multiple sclerosis. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1995; 4:151-3. [PMID: 7711824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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77
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Marsischky GT, Wilson BA, Collier RJ. Role of glutamic acid 988 of human poly-ADP-ribose polymerase in polymer formation. Evidence for active site similarities to the ADP-ribosylating toxins. J Biol Chem 1995; 270:3247-54. [PMID: 7852410 DOI: 10.1074/jbc.270.7.3247] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Sequence similarities between the enzymatic region of poly-ADP-ribose polymerase and the corresponding region of mono-ADP-ribosylating bacterial toxins suggest similarities in active site structure and catalytic mechanism. Glu988 of the human polymerase aligns with the catalytic glutamic acid of the toxins, and replacement of this residue with Gln, Asp, or Ala caused major reductions in synthesis of enzyme-linked poly-ADP-ribose. Replacement of any of 3 other nearby Glu residues had little effect. The Glu988 mutations produced similar changes in activity in the carboxyl-terminal 40-kDa catalytic fragment fused to maltose-binding protein: E988Q and E988A reduced polymer elongation > 2000-fold, and E988D approximately 20-fold. Smaller changes were seen in chain initiation. The mutations had little effect on the Km of NAD, indicating a predominantly catalytic function for Glu988. The results support the concept of similar active sites of the polymerase and the ADP-ribosylating toxins. Glu988 may function in polymer elongation similarly to the toxins' active site glutamate, as a general base to activate the attacking nucleophile (in the case of the polymerase, the 2'-OH of the terminal adenosine group of a nascent poly-ADP-ribose chain).
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Wilson BA. Understanding ACE inhibitors. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1995; 4:62-64. [PMID: 7874224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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79
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Wilson BA, Ivani-Chalian R. Performance of adults with Down's syndrome on the children's version of the Rivermead Behavioural Memory Test: a brief report. BRITISH JOURNAL OF CLINICAL PSYCHOLOGY 1995; 34:85-8. [PMID: 7757043 DOI: 10.1111/j.2044-8260.1995.tb01440.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We gave the Rivermead Behavioural Memory Test for Children (RBMT-C) to 37 community dwelling adults with Down's syndrome. Ages ranged from 19 to 44 years (mean 29 years, SD 6 years). We wanted to know (a) if the test could be administered to this group and (b) how people with Down's syndrome compared with children aged 5 to 10 years. All subjects were able to participate in the test and all were 'off the floor'. Story recall was the hardest subtest for people with Down's syndrome, while remembering to deliver a message was the easiest. We discuss the possible use of this test in studies comparing older people with Down's syndrome with Alzheimer patients.
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80
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Wilson BA, Bar-Or O, O'Byrne PM. The effects of indomethacin on refractoriness following exercise both with and without a bronchoconstrictor response. Eur Respir J 1994; 7:2174-8. [PMID: 7713200 DOI: 10.1183/09031936.94.07122174] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Repeated exercise tests demonstrate refractoriness to the development of exercise-induced asthma (EIA). It is unclear whether it is the initial exercise per se or the resulting bronchoconstriction that causes the attenuated response to the second exercise challenge. This study was designed to determine whether the reported blocking of the refractory period by indomethacin requires a significant bronchoconstriction following the primary exercise challenge. Thirteen asthmatic teenagers (aged 12-16 yrs) were tested on four visits. Each visit included two 7 min treadmill exercise challenges at 80% maximum heart rate, separated by a 30 min rest. Conditions for the second exercise challenge (Ch2) were always thermoneutral (20-22 degrees C and 25-35% relative humidity (RH); whilst challenge one (Ch1) was completed twice in thermoneutral and twice in warm-humid breathing conditions (33-35 degrees C and 90-95% RH). A pretreatment for 3 days in a double-blind design with either placebo or indomethacin was completed. Forced expiratory volume in one second (FEV1) was measured before and repeatedly following each challenge. The % fall in FEV1 following Ch1 of the placebo thermoneutral trial was taken as reference. "Percent protection" at each visit was expressed as the decrease in EIA following Ch2, compared to reference. Warm-humid breathing reduced the EIA post Ch1 by 75%, whilst providing similar protection to thermoneutral conditions. Indomethacin had no significant effect on EIA after Ch1, but reduced "percent protection" for both warm-humid (from 67 to 16%) and thermoneutral (from 70 to 26%) conditions.(ABSTRACT TRUNCATED AT 250 WORDS)
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81
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Wilson BA. Amiodarone (Cordarone): what every nurse should know. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1994; 3:411-3. [PMID: 7812341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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82
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Wilson BA, Blanke SR, Reich KA, Collier RJ. Active-site mutations of diphtheria toxin. Tryptophan 50 is a major determinant of NAD affinity. J Biol Chem 1994; 269:23296-301. [PMID: 8083236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The two active-site tryptophans of diphtheria toxin, Trp-50 and Trp-153, were individually or jointly replaced with phenylalanine or alanine by directed mutagenesis of a synthetic gene for the toxin's catalytic A fragment. Substitution of Trp-50 with alanine (W50A) decreased the ADP-ribosyltransferase activity by nearly 10(5)-fold and reduced NAD-glycohydrolase activity beyond the limits of our detection. Effects of the W153A mutation on these activities were less dramatic, < 40-fold decrease in ADP-ribosylation and < 10-fold decrease in NAD glycohydrolysis. The W50F and W153F substitutions caused only minimal reductions (< 2-fold) in enzyme activities and NAD affinity. Decreases in affinity for NAD in the initial, ground state complex, as measured by intrinsic protein fluorescence, correlated well with the reductions in enzyme activity. None of the mutations caused greater than a 10-fold decrease in NAD affinity for the ternary Michaelis complex in the ADP-ribosylation reaction; and none caused significant increase in susceptibility to proteolytic digestion by trypsin. The results indicate that Trp-50 is a major determinant of NAD affinity. Also, they identify this residue as a candidate for modification in the development of inactive forms of the toxin for use in vaccine development.
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83
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Wilson BA. The management of memory disorders in adults. BRITISH JOURNAL OF CLINICAL PSYCHOLOGY 1994; 33:413-5. [PMID: 7994228 DOI: 10.1111/j.2044-8260.1994.tb01138.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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84
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Wilson BA. Understanding management of hyperlipidemia. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1994; 3:319-21. [PMID: 7920858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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85
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Wilson BA. Syndromes of acquired dyslexia and patterns of recovery: a 6- to 10-year follow-up study of seven brain-injured people. J Clin Exp Neuropsychol 1994; 16:354-71. [PMID: 7929703 DOI: 10.1080/01688639408402646] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Seven subjects who were neurologically impaired following encephalitis (n = 2), head injury (n = 3), and stroke (n = 2) were referred several years previously because of acquired dyslexia. Two were almost totally alexic, 2 were surface dyslexic, 2 were deep dyslexic and 1 was a letter-by-letter reader. Following a period of rehabilitation, the 2 with alexia became surface dyslexic and letter-by-letter readers; 1 of the deep dyslexics showed some improvements but remained a deep dyslexic; and the letter-by-letter reader learned to read more quickly. At follow-up, 6 to 10 years later, there had been little significant change. The 2 subjects whose alexia resolved into surface dyslexia with letter-by-letter reading had increased their reading ages but remained surface dyslexic and letter-by-letter readers. The subject who had been a letter-by-letter reader was faster at easier and more frequently used words but slower at harder, less frequently used words. Changes in the other 4 subjects were negligible. Implications for rehabilitation are discussed.
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Wilson BA. Zofran: first of a new class of antiemetics. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1994; 3:218-9. [PMID: 8055040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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87
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Robertson IH, Halligan PW, Bergego C, Hömberg V, Pizzamiglio L, Weber E, Wilson BA. Right neglect following right hemisphere damage? Cortex 1994; 30:199-213. [PMID: 7924345 DOI: 10.1016/s0010-9452(13)80193-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
From a sample of 90 stroke cases showing visual inattention following right hemisphere brain damage, 17 cases were identified who showed more inattention on the right than the left side on some tests. Eight of these subjects had CT scan-confirmed unilateral right hemisphere damage and one of these eight had MRI scan-confirmed unilateral right brain damage. A number of hypotheses are examined to explain this "paradoxical" right inattention. The most parsimonious proposes that right inattention is produced by an interaction of a compensatory left sided scanning strategy in association with a non-lateralised attentional loss.
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de Wall C, Wilson BA, Baddeley AD. The Extended Rivermead Behavioural Memory Test: a measure of everyday memory performance in normal adults. Memory 1994; 2:149-66. [PMID: 7584289 DOI: 10.1080/09658219408258942] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Rivermead Behavioural Memory Test provides a well-validated instrument for detecting everyday memory problems in patient groups. It was however designed as a screening test, and thus is insufficiently sensitive to detect mild deficits, whether due to brain damage or to the introduction of a drug or stressor. The Extended Rivermead Behavioural Memory Test (ERBMT) increases the level of difficulty by doubling the amount of material to be remembered, by combining material from Forms A and B, and Forms C and D of the original test to produce two parallel versions of the new extended test. The sensitivity of the ERBMT was assessed by comparing the performance of a middle-aged and an elderly group of normal subjects, who would be expected to show modest differences in memory performance. The subtests varied in their sensitivity to this small age difference, but when performance was assessed in terms of scaled scores that allow an overall combined measure of memory performance to be calculated, the test proved sensitive (t = 4.87, P < 0.0001), and free of ceiling and floor effects. We suggest that the ERBMT provides a promising measure of everyday memory in normal adults.
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Blanke SR, Huang K, Wilson BA, Papini E, Covacci A, Collier RJ. Active-site mutations of the diphtheria toxin catalytic domain: role of histidine-21 in nicotinamide adenine dinucleotide binding and ADP-ribosylation of elongation factor 2. Biochemistry 1994; 33:5155-61. [PMID: 8172890 DOI: 10.1021/bi00183a019] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Diphtheria toxin (DT) has been studied as a model for understanding active-site structure and function in the ADP-ribosyltransferases. Earlier evidence suggested that histidine-21 of DT is important for the ADP-ribosylation of eukaryotic elongation factor 2 (EF-2). We have generated substitutions of this residue by cassette mutagenesis of a synthetic gene encoding the catalytic A fragment (DTA) of DT, and have characterized purified mutant forms of this domain. Changing histidine-21 to alanine, aspartic acid, leucine, glutamine, or arginine diminished ADP-ribosylation activity by 70-fold or greater. In contrast, asparagine proved to be a functionally conservative substitution, which reduced ADP-ribosylation activity by < 3-fold. The asparagine mutant was approximately 50-fold-attenuated in NAD glycohydrolase activity, however. Dissociation constants (Kd) for NAD binding, determined by quenching of the intrinsic protein fluorescence, were 15 microM for wild-type DTA, 160 microM for the asparagine mutant, and greater than 500 microM NAD for the alanine, leucine, glutamine, and arginine mutants. These and previous results support a model of the ADP-ribosylation of EF-2 in which histidine-21 serves primarily a hydrogen-bonding function. We propose that the pi-imidazole nitrogen of His-21 hydrogen-bonds to the nicotinamide carboxamide, orienting the N-glycosidic bond of NAD for attack by the incoming nucleophile in a direct displacement mechanism, and then stabilizing the transition-state intermediate of this reaction.
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Wilson BA. What nurses don't know about managing NIDDM. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1994; 3:152-4. [PMID: 8173627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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91
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Falnes PO, Choe S, Madshus IH, Wilson BA, Olsnes S. Inhibition of membrane translocation of diphtheria toxin A-fragment by internal disulfide bridges. J Biol Chem 1994; 269:8402-7. [PMID: 8132565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Fragment A of diphtheria toxin is translocated to the cytosol when the toxin is presented to receptor-positive cells. The toxin binds to cell surface receptors through its B-fragment, and after endocytotic uptake, the low endosomal pH triggers translocation of the A-fragment across the membrane. Translocation can also be induced at the level of the plasma membrane by exposure to low pH medium. Based on the diphtheria toxin crystal structure, we made five double cysteine mutants of the A-fragment, each expected to form an intramolecular disulfide bond. Four of the double cysteine mutants efficiently formed an intramolecular disulfide bridge, and these same mutants showed a strong reduction in their translocating ability. The inhibition of translocation was observed both when the toxin was endocytosed and when translocation was induced by exposing surface-bound toxin to low pH. The data indicate that extensive unfolding of the A-fragment is required for translocation.
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Wood DR, Poullet P, Wilson BA, Khalil M, Tanaka K, Cannon JF, Tamanoi F. Biochemical characterization of yeast RAS2 mutants reveals a new region of ras protein involved in the interaction with GTPase-activating proteins. J Biol Chem 1994; 269:5322-7. [PMID: 8106517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We report biochemical characterization of two recently identified mutants of yeast RAS2, RAS2-E99K and RAS2-E130K. These mutants exhibit dominant activating phenotypes in yeast. Characterization of their intrinsic GTPase and GDP dissociation as well as their ability to stimulate adenylate cyclase showed that these activities of RAS2-E99K mutant protein were similar to those of the wild type protein. RAS2-E130K protein, on the other hand, differed from the wild type protein with a fast GDP dissociation rate and 2-fold higher activation of adenylate cyclase. When the sensitivity to GTPase-activating protein (GAP) was examined, we found that the RAS2-E99K protein was approximately 1200-fold less sensitive to NF1-GAP activity. In addition, the affinity for NF1 as revealed by competition binding experiments was reduced more than 150-fold with RAS2-E99K protein. Thus, the RAS2-E99K mutation affects interaction with GAP proteins. This mutation is particularly interesting because it is the first mutation identified in the alpha 3 region of ras protein that affects GAP interaction. The alpha 3 region appears to be directly involved in interaction with NF1, since peptides containing the sequence encompassing residue 99 of RAS2 inhibit NF1-GAP activity. These results suggest that the interaction between ras and GAP involves a larger region within ras than previously recognized.
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Wilson BA. Enoxaparin and a new look at clot prevention. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1994; 3:66-67. [PMID: 8124383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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94
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Abstract
We propose that one of the major functions of explicit memory is the elimination of learning errors. The hypothesis is explored by means of a stem completion task in which subjects are presented with stems having many potential completions, and in the initial phase are either encouraged to guess, the "errorful" procedure, or are provided with the correct completion, the "errorless" condition. Learning is then tested over a sequence of nine trials. The performance of amnesic subjects who are assumed to have good implicit but bad explicit learning is compared with that of normal elderly subjects, who are assumed to have an intermediate level of explicit learning skill, and young controls who are expected to be high in both implicit and explicit learning capacity. As predicted, errorless learning is beneficial, with the effect being particularly marked for the amnesic group. A detailed analysis of the intrusion errors supports an interpretation of the results in terms of the relative contribution to the three groups of implicit learning, which is assumed to be particularly vulnerable to interference. Implications for the analysis of normal learning, and for the rehabilitation of brain damaged patients are discussed.
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Wilson BA, Khalil M, Tamanoi F, Cannon JF. New activated RAS2 mutations identified in Saccharomyces cerevisiae. Oncogene 1993; 8:3441-5. [PMID: 8247549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Activating mutations in RAS proto-oncogenes encode proteins with greater GTP binding. Such mutant proteins are responsible for many human cancers. Six new amino acids were discovered that can yield an activated Saccharomyces cerevisiae RAS2 protein when they are altered. These new RAS2 alleles were found among a collection of 35 random mutations that exhibit a dominant reduction of glycogen accumulation. The RAS2-P41S and RAS2-E99K alleles encode proteins that have lost responsiveness to GTPase activating proteins. They affect amino acids in loop 2 and helix 3 respectively and illustrate that GTPase activating proteins recognize a larger portion of the RAS structure than previously realized. RAS2 mutations E130K, S153F, A154T, and A157S alter amino acids proximal to the guanine binding site and probably influence nucleotide binding either directly or indirectly.
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Wilson BA. Tamoxifen for breast cancer therapy: nursing implications. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1993; 2:494-5. [PMID: 8261005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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97
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Baddeley A, Wilson BA. A case of word deafness with preserved span: implications for the structure and function of short-term memory. Cortex 1993; 29:741-8. [PMID: 8124947 DOI: 10.1016/s0010-9452(13)80294-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Case IJ shows impaired capacity to repeat individual words despite normal hearing as measured by audiometry and tympanometry. She also has difficulty in identifying other environmental sounds. Her phonological memory span for visually-presented material is normal, and her memory span for spoken digits is only slightly impaired. It is suggested that she has a pre-phonological auditory processing deficit; the implications of this for discussion of the role of phonological short-term memory in language processing are discussed.
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Malseed RT, Wilson BA. Pharmacologic management of systemic lupus erythematosus: nursing implications. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1993; 2:422-4. [PMID: 8220648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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99
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Abstract
We describe a young woman, J.R., who sustained a very severe head injury in 1981 at the age of 17 years. She was assessed in 1982 and found to have visual agnosia. Since then J.R. has been assessed on several occasions over a period of ten years. Her agnosia for real objects has resolved and she has improved on the identification of other classes of stimuli. However, she still has some problems with the identification of line drawings, photographs and model animals. Her drawing from memory remains particularly poor and she has difficulty with visual imagery. We consider her residual deficits in the light of Farah's (1990) theoretical framework; this proposes that associative agnosia could be due to a disconnection syndrome, a loss of stored visual representations or to the loss of knowledge of how to perceive objects. J.R.'s residual impairments appear to be mainly due to a loss of access to visual representations in the absence of visual input.
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Wilson BA. Understanding corticosteroids: pharmacologic and adverse effects. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1993; 2:322-324. [PMID: 8348190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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