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71.
72.
Gal G Mendlovic S Bloch Y Beitler G Levkovitz Y Young AM Feldon J Ratzoni G 《Behavioural brain research》2005,159(2):267-275
Learned irrelevance (LIrr) is a pre-exposure effect in which uncorrelated presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US) retard subsequent CS-US association. LIrr is closely related to the phenomenon of latent inhibition (LI). LI refers to the retarding effects of inconsequential stimulus pre-exposure on subsequent conditioning to that stimulus, and is considered to reflect the organism's capacity to ignore irrelevant stimuli. LI is disrupted in schizophrenia patients, due to faster learning of the association between the preexposed CS and the US. A new within-subject target-recognition LIrr procedure was applied. The target was either cued by a priming signal or appeared at random, and priming signals were novel or preexposed cues. Schizophrenia patients were compared to age- and sex-matched control subjects. Normal subjects (n = 24) have shown robust LIrr, namely, faster cue-target associations of novel compared to preexposed cues. Schizophrenia patients at the early stages of their first episode (n = 7) showed LIrr disruption, namely, cue-target associations to preexposed cues were as fast as for novel cues. Chronic patients during an acute phase (n = 18) did not show LIrr as they failed to learn the cue-target association. In addition to the LIrr paradigm the same subjects were tested in a covert-orientation task. No differences were observed between the groups on this task. The possible advantages of the new LIrr paradigm are discussed. 相似文献
73.
Dohrenwend BP Neria Y Turner JB Turse N Marshall R Lewis-Fernandez R Koenen KC 《Journal of consulting and clinical psychology》2004,72(3):417-433
A 70.9% majority of the U.S. male veterans in a nationwide sample appraised the impact of their service in Vietnam on their present lives as mainly positive. A substantial minority, 41.7%, judged the effects to be highly salient. With controls on level of exposure to war-zone stressors measured with data from military records, the valence and salience of these appraisals are investigated in relation to posttraumatic stress disorder (PTSD) and other indicators of wartime and postwar functioning. The results are consistent with the hypothesis that mainly positive tertiary appraisals are affirmations of successful wartime and postwar adaptation rather than defensive denials related to maladaptive outcomes. The possibility that mainly positive tertiary appraisals also contribute to successful postwar adaptation is discussed. 相似文献
74.
Bloom AI Verstandig A Gielchinsky Y Nadiari M Elchalal U 《BJOG : an international journal of obstetrics and gynaecology》2004,111(8):880-884
Arterial embolisation is a recognised treatment for postpartum haemorrhage (PPH). In this retrospective study, we evaluate its use in the management of persistent PPH. Records of all births during a 54 month period at a university hospital were analysed. Two sub-groups were identified. Group I (n= 5), underwent embolisation after hysterectomy and Group II (n= 4), had embolisation as a first-line theraphy without hysterectomy. Of 20,215 births, there were 636 cases of PPH (3.1%). Nine required embolisation to control bleeding (1.4%). Group I needed multiple surgical procedures, had a larger pre- and post-operative blood requirement (12-100, median 22 units, vs. 6-12, median 8.5 units), longer embolisation (33-93, median 54 minutes, vs 20-66, 47 minutes) with a larger radiation exposure (5194-9067, median 6301 dGy, vs. 269-3862, median 950 dGy), a longer intensive care stay (3-7, median four days vs. 0-1.5, median one day), and more complications, when compared with Group II. Three of four women from Group II resumed menstrual function. Embolisation prior to hysterectomy may be preferable to embolisation after hysterectomy for the control of PPH. 相似文献
75.
Cultured mucosal grafts (CMG) are among recently developed biological grafting materials to cover large oral mucosal defects following resection of mucosal pathology. This study evaluates the effect of donor's age on the cultivation process of oral mucosal keratinocytes for grafting. Human mucosal epithelial cells were utilized and classified into three donor age groups: 3-30 years (14 patients); 31-60 years (9 patients); and >60 years (6 patients) (11 males and 18 females). Isolation and cultivation of oral mucosal keratinocytes were according to Rheinwald and Green [Cell 6 (1975) 331], originally developed for epidermal keratinocytes. Isolated primary cell lines were seeded and cultivated. Propagation of cell lines ("passages"), time period required to reach confluence, yield of cells and plating efficiency were recorded. All cells propagated well up to the fourth passage. Thereafter, a decline was observed and was more distinct with age. Period to confluence was longer among the old age group. Yield of cells in fourth passage was high among the young age group and decreased with age. Plating efficiency in passages 4-6 decreased with age. These results suggest that age-related changes in cultivation of oral keratinocytes are not general phenomena, but rather limited to the donor age of 60 years and above. In this age group all the parameters studied were adversely affected. Oral mucosal keratinocytes may be a useful model for oral aging. 相似文献
76.
77.
Fatal exertional heat stroke: a case series 总被引:1,自引:0,他引:1
Rav-Acha M Hadad E Epstein Y Heled Y Moran DS 《The American journal of the medical sciences》2004,328(2):84-87
BACKGROUND: Exertional heat stroke (EHS) is one of the most serious conditions that occur when excess heat, generated by muscular exercise, exceeds the body's heat-dissipation rate. The consequent elevated body core temperature causes damage to the body's tissues, resulting in a characteristic multiorgan syndrome, which is occasionally fatal. METHODS: We analyzed the fatal EHS cases that occurred in the Israeli Defence Forces during the last decade according to Minard's paradigm for evaluation of EHS predisposing factors, aiming to characterize the common features and unique circumstances leading to fatality. RESULTS: Accumulation of predisposing factors, particularly those concerning training regulations, coupled with inappropriate treatment at site, were found to be strong predictors of a grave prognosis. Analysis of the pathologic findings of the fatal EHS cases on autopsy revealed a possible association between the duration and length of exercise prior to EHS occurrence and the extent of pathologic findings. CONCLUSIONS: Strict adherence to existing training regulations may prevent further heat stroke fatalities. 相似文献
78.
79.
Axer-Siegel R Ehrlich R Weinberger D Rosenblatt I Shani L Yassur Y Priel E Kramer M 《American journal of ophthalmology》2004,138(4):602-607
PURPOSE: To evaluate the visual outcome of patients with myopic subfoveal choroidal neovascularization (CNV) given photodynamic therapy (PDT) in a clinical setting, and to identify potential relation between the visual outcome and the age at treatment. DESIGN: Interventional case series. METHODS: Retrospective comparative study. SETTING: Outpatient ophthalmology clinic. PATIENTS: Twenty-nine consecutive patients (30 eyes) with subfoveal CNV caused by pathologic myopia who were treated with verteporfin PDT from January 2000 to May 2003. INTERVENTION: All the patients received verteporfin PDT and were followed clinically and with fluorescein angiography (FA). Review of the medical records and angiograms was performed. Patients were divided into two groups by age, using the median age (60 years) as the cutoff. MAIN OUTCOME MEASURES: Visual acuity (VA) at the end of follow-up in the older-patient group compared with the younger-patient group. RESULTS: The mean age was 63.1 years. Mean follow-up was 11.5 months. Patients received a mean of 3.48 treatments. Mean VA improved in the younger group from 0.63 to 0.39 logMAR (P = .02, paired t test) and deteriorated in the older group from 0.71 to 0.99 logMAR (P = .03, paired t test). In the whole cohort, 33% of eyes lost 3 or more lines of Snellen best-corrected VA; in the older age group, 50% of eyes lost 3 or more lines, whereas in the younger age group, only 8% of eyes did so (P = .024, Fisher's exact test). CONCLUSIONS: In our consecutive case series, visual prognosis of myopic CNV after PDT was found to be influenced by age at treatment. 相似文献
80.