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1.
Neuropsychologists often diagnose cerebral dysfunction based, in part, on marked variation in an individual's cognitive test performance. However, little is known about what constitutes the normal range of intraindividual variation. In this study, after excluding 54 individuals with significant health problems, we derived 32 z-transformed scores from 15 tests administered to 197 adult participants in a study of normal aging. The difference between each person's highest and lowest scores was computed to assess his or her maximum discrepancy (MD). The resulting MD values ranged from 1.6 to 6.1 meaning that the smallest MD shown by any person was 1.6 standard deviations (SDs) and the largest MD shown by any person was 6.1 SDs. Sixty-six percent of participants produced MD values that exceeded 3 SDs. Eliminating each person's highest and lowest test scores decreased their MDs, but 27% of the participants still produced MD values exceeding 3. Although MD values appeared to increase with age, adjusting test scores for age, which is standard in clinical practice, did not correct for this. These data reveal that marked intraindividual variability is very common in normal adults, and underscore the need to base diagnostic inferences on clinically recognizable patterns rather than psychometric variability alone.  相似文献   
2.
OBJECTIVE: This study sought to determine whether volumes of the hippocampus and amygdala are disproportionately smaller in subjects with Down's syndrome than in normal comparison subjects and whether volume reduction is greater in Down's syndrome subjects with dementia. METHOD: The subjects were 25 adults with Down's syndrome (eight with dementia) and 25 cognitively normal adults who were individually matched on age, sex, and race. Magnetic resonance imaging measures included volumes of the hippocampus, amygdala, and total brain. Nineteen of the Down's syndrome subjects had follow-up scans (interscan interval = 9-41 months). RESULTS: Nondemented Down's syndrome subjects had significantly smaller volumes of the hippocampus, but not the amygdala, than their comparison subjects, even when total brain volume was controlled for. Volumes of both the hippocampus and the amygdala were smaller in the demented Down's syndrome subjects than in their comparison subjects, even when total brain volume was controlled for. Age was not correlated with volume of the hippocampus or amygdala among the nondemented Down's syndrome subjects and the comparison subjects; age was correlated with volume of the amygdala, but not the hippocampus, among the Down's syndrome subjects with dementia. Changes in volume over time were not statistically significant for either the demented or the nondemented subjects. CONCLUSIONS: Hippocampal volume, while disproportionately small for brain size in individuals with Down's syndrome, remains fairly constant through the fifth decade of life in those without dementia. All subjects over age 50 who had Down's syndrome demonstrated volume reduction in the hippocampus as well as clinical signs of dementia. Dementia was also associated with volume reductions in the amygdala that exceeded reductions in total brain volume.  相似文献   
3.
Davis  GD; Fulton  RE; Ritter  DG; Mair  DD; McGoon  DC 《Radiology》1978,128(1):133-144
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries.  相似文献   
4.
神经母细胞瘤(neuroblastoma,NB)是儿童最常见的颅外实体肿瘤,临床表现及预后具有高度异质性。低危患儿预后较好,高危患儿即使接受化疗、放疗、手术、造血干细胞移植等多种方法的综合治疗,长期存活率仍不足50%。探索潜在的治疗靶点对于提高高危患者的生存率具有重要意义。双唾液酸神经节苷脂抗原GD2在NB细胞高表达,达妥昔单抗β可与NB细胞膜表面过表达的GD2特定靶点结合,触发抗体依赖性细胞介导的细胞毒性作用和补体依赖的细胞毒性效应,通过双重免疫机制而发挥抗肿瘤作用。通过总结国外多项关键临床研究,并结合在海南和天津医疗先行区的上市前初步应用经验,我们对达妥昔单抗β的安全性、有效性、适用人群及使用方法进行总结和推荐,提出本共识,旨在为临床医师提供指导与帮助。  相似文献   
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We recently reported a significant increase in the frequency of carriers of grey zone (GZ) alleles of FMR1 gene in Australian males with Parkinson's disease (PD) from Victoria and Tasmania. Here, we report data comparing an independent sample of 817 PD patients from Queensland to 1078 consecutive Australian male newborns from Victoria. We confirmed the earlier finding by observing a significant excess of GZ alleles in PD (4.8%) compared to controls (1.5%). Although both studies provided evidence in support of an association between GZ‐carrier status and increased risk for parkinsonism, the existing evidence in the literature from screening studies remains equivocal and we discuss the need for alternative approaches to resolve the issue.  相似文献   
8.
Disrupted sensory processing is a core feature of psychotic disorders. Auditory paired stimuli (PS) evoke a complex neural response, but it is uncertain which aspects reflect shared and/or distinct liability for the most common severe psychoses, schizophrenia (SZ) and psychotic bipolar disorder (BDP). Evoked time‐voltage/time‐frequency domain responses quantified with EEG during a typical PS paradigm (S1‐S2) were compared among proband groups (SZ [n = 232], BDP [181]), their relatives (SZrel [259], BDPrel [220]), and healthy participants (H [228]). Early S1‐evoked responses were reduced in SZ and BDP, while later/S2 abnormalities showed SZ/SZrel and BDP/BDPrel specificity. Relatives' effects were absent/small despite significant familiality of the entire auditorineural response. This pattern suggests general and divergent biological pathways associated with psychosis, yet may reflect complications with conditioning solely on clinical phenomenology.  相似文献   
9.
Alzheimer’s disease (AD) is most commonly detected during old age, but the underlying neuropathologic changes likely appear decades earlier, especially among patients possessing genetic risk factors, such as the isoform E4 of the apolipoprotein E (ApoE4). In this study, we used magnetic resonance imaging (MRI) to assess default mode network (DMN) connectivity in 22 ApoE4 non-carriers and 14 matched ApoE4 carriers as well as white matter fractional anisotropy (FA) in 15 ApoE4 non-carriers and 11 demographically matched ApoE4 carriers. Cognitive tests were also administered. All of the participants were middle-aged adults. The analysis revealed no cognitive or white matter FA differences between carriers and non-carriers. However, in DMN regions previously implicated in AD, we did detect decreased functional connectivity. Our findings suggest that functional MRI abnormalities may be detectable well before cognitive decline or white matter changes among individuals at increased genetic risk for AD.  相似文献   
10.
Background: For some people with aphasia, returning to work will be their eventual goal. While there are reports in the literature of incidence of return to work, and general discussion of success, there are few documented in depth studies of what this might entail for the individual with aphasia.

Aims: This paper explores returning to work with aphasia, and examines the complex relationship between the person, the aphasia and the demands of employment.

Methods & Procedures: This is a detailed case report, describing and reflecting on the experiences of GD, who returned to work following his stroke and aphasia. Therapy focused specifically on work requirements is described and the factors affecting GD's return to work explored. An interview was used to elicit GD's reflections on his experiences.

Outcome & Results: GD's language skills improved over time and with therapy, and he developed several strategies that facilitated his communication. He was able to return to work (part-time) in a modified role and this was successful initially. After an extended period (~19 months) his employment was terminated and GD explored other options. He moved on to a volunteering and charity trustee role.

Conclusions: The success (or not) of returning to work with aphasia is multi-faceted and does not rest solely with the person with aphasia. The nature of the work may have a strong bearing on success, as will the ability and willingness of the employer to engage in the process. Partnership with the person and constant review of goals and management is of overwhelming importance. We need to consider what “success” may mean in this context and the need to consider therapeutic and rehabilitation needs over a longer time frame.  相似文献   
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