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81.
Cognitive function in depression: a distinct pattern of frontal impairment in melancholia? 总被引:18,自引:0,他引:18
Austin MP Mitchell P Wilhelm K Parker G Hickie I Brodaty H Chan J Eyers K Milic M Hadzi-Pavlovic D 《Psychological medicine》1999,29(1):73-85
BACKGROUND: Although depressed patients demonstrate impaired performance on a range of neuropsychological tests, there is little research that examines either frontal cognitive deficits or possible differences in test performance between melancholic and non-melancholic subtypes. METHODS: Depressed subjects were administered a broad neuropsychological battery. In an overall analysis, 77 depressed subjects were compared with 28 controls. In a second set of analyses, the depressed sample was divided into melancholic and non-melancholic subsets according to DSM-III-R, the CORE system and the Newcastle scale. These depressed subsets were contrasted to controls and with each other using ANCOVA controlling for age, IQ, simple reaction time and Hamilton Depression scores where appropriate. RESULTS: The total depressed sample was impaired on most mnemonic tasks, simple reaction time and Trails B. Similar findings applied to DSM-III-R melancholic and non-melancholic subjects. When defined by the CORE and Newcastle (narrower definitions of melancholia), melancholic patients were additionally impaired on WCST (perseverative response) and (for Newcastle) digit symbol substitution. In contrast, the cognitive performance of the CORE and Newcastle-defined non-melancholic patients was largely unimpaired. CONCLUSIONS: Using narrower definitions of melancholia, i.e. CORE and (in particular) Newcastle, melancholic patients were impaired on mnemonic tasks and tasks of selective attention, and set-shifting while non-melancholic subjects were largely unimpaired in their cognitive performance. These differences may be due to impairment of specific neuroanatomical regions in narrowly defined melancholic patients, in particular the anterior cingulate. 相似文献
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Diagnostic usefulness and safety of transtracheal aspiration 总被引:10,自引:0,他引:10
R W Kalinske R H Parker D Brandt P D Hoeprich 《The New England journal of medicine》1967,276(11):604-608
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T R Pritchett A W Kanzler P W Nichols A C Bakke M K Hechinger D G Skinner J W Parker 《American journal of clinical pathology》1985,84(2):191-196
DNA measurement by flow cytometry has been demonstrated to be a potentially useful technic in the diagnosis of bladder cancer by detecting neoplastic cells in bladder washings and urine specimens. The authors' goal was to develop a simple and practical method utilizing the new generation of cytofluorographs designed for use in the clinical laboratory. This method combined direct fixation with cell lysis yielding fixed intact nuclei. Following RNase and pepsin digestion, the nuclei were separated from debris and aggregates on a sucrose barrier, stained with ethidium bromide, and analyzed with an argon laser analytic cytofluorograph. Urines and bladder washings from 14 patients with positive urinary cytology and histologically diagnosed bladder cancers were compared with specimens from patients without urothelial malignancies. DNA histograms clearly delineated aneuploid from diploid populations and often identified S, G2M, and G1 phase nuclei. Aneuploid populations have been detected in all tumor specimens with positive cytologies studied to date. 相似文献
88.
H-2 restriction and serotype crossreactivity of anti-reovirus cytotoxic T lymphocytes (CTL) 总被引:1,自引:0,他引:1
Murine anti-reovirus cytotoxic T lymphocytes (CTLs) were analyzed for H-2 restricted recognition of virus infected target cells and for potential cross-reactivity with cells infected by reovirus serotype 1 (T1; Lang strain) or by serotype 3 (T3; Dearing strain). Anti-reovirus CTL specifically lysed virus infected cells and lysis was shown to be H-2 restricted by the H-2Dd, H-2Ld, H-2Kd, H-2Kb, and H-2Kk antigens. No H-2 antigens were identified which failed to restrict virus recognition by anti-reovirus CTL. Anti-T1 and anti-T3 CTLs were also shown to crossreact completely with cells infected with the opposite virus serotype. Thus, anti-reovirus CTLs are restricted by a broad spectrum of H-2 antigens and they detect common rather than unique structural components of these two viral serotypes. 相似文献
89.
Transforming growth factor-beta3-loaded microtextured membranes for skin regeneration in dermal wounds 总被引:1,自引:0,他引:1
Vooijs DP Walboomers XF Parker JA Von den Hoff JW Jansen JA 《Journal of biomedical materials research. Part A》2004,70(3):402-411
Adverse effects of wound healing, such as excessive scar tissue formation, wound contraction, or nonhealing wounds represent a major clinical issue in today's healthcare. Transforming growth factor (TGF)-beta3 has specifically been implicated in wound healing. Our hypothesis was that local administration of TGF-beta3 to excisional dermal wounds would diminish wound contraction and scar formation. Microtextured wound covers, containing different concentrations of TGF-beta3, were placed onto full-thickness excisional skin wounds in guinea pigs. Tattooed reference marks were used to quantify wound contraction. Sixty-four male guinea pigs in four study groups (5 ng TGF-beta3, 50 ng TGF-beta3, no growth factor, sham wound) were followed for up to 6 weeks. We analyzed 19 different parameters of wound healing. Results showed that, in some instances, the 50-ng TGF-beta3 group gave less contraction, whereas the 5-ng TGF-beta3 group gave more contraction. These differences confirm that TGF-beta3 has an optimum working concentration, and suggest this concentration to be closer to 50 ng than to 5 ng TGF-beta3. However, only very few significant differences occurred, and thus we conclude that the clinical relevance of our findings is negligible. Earlier studies, reporting clinically improved wound healing by TGF-beta3, could therefore not be confirmed by this study. 相似文献
90.
Increased incidence of HL-A 1 and 8 in patients showing IgG or complement coating on their red cells 总被引:2,自引:0,他引:2 下载免费PDF全文
J. A. G. Da Costa A. G. White A. C. Parker G. B. Grigor 《Journal of clinical pathology》1974,27(5):353-355
The incidence of HL-A antigens in patients having a variety of medical conditions, but sharing the common feature of a positive antiglobulin test of the red cells, was determined. There was a significant increase in the antigens HL-A 1 and HL-A 8 and of the 1 and 8 combination when compared with a control group. It is suggested that the presence of these antigens may predispose to autoallergy. 相似文献