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81.
In this study we aimed to work out a quantitative prognostic index for preoperative assessment of brain technetium-99m hexamethylpropylene amine oxime (HMPAO) single-photon emission tomography (SPET) in patients referred for urgent carotid endarterectomy due to acute obstructive disease of the internal carotid artery (ICA) and neurological deficit. To this end we compared data from preoperative SPET studies with the postinterventional changes in neurological status in 20 patients (17 males, three females; mean age 53 years, SD 4 years) with acute ischaemic cerebral disorders induced by obstruction of the ICA. Carotid obstruction was diagnosed by ultrasound B-mode study. All patients underwent urgent carotid endarterectomy from the ICA. Patients were divided into two groups in accordance with the results of postoperative follow-up: group A comprised patients with significant (more than 3 points) postoperative improvement in neurological condition as quantified by the Canadian Neurological Scale (11 patients); group B consisted of patients with minimal improvement or deterioration (nine, three of whom died). All patients were studied preoperatively by99mTc-HMPAO SPET. The volume of nonperfused tissue (VS, cm3) was quantified using the Mountz technique. Hypoperfused volume (V hypoperf, cm3) in the affected hemisphere was calculated as the total volume of voxels with99mTc-HMPAO uptake <90% of the contralateral symmetric voxels. Discriminant prognostic function was calculated by discriminant analysis as:PF = 0.072×VS + 29.46×(VS/V hypoperf). Patients with preoperativePF values <8.20 demonstrated postoperative improvement in neurological status, while the group withPF>8.90 comprised patients who demonstrated minimal improvement or deterioration. PF values in the range 8.20–8.90 carried an indefinite prognosis. We conclude that the preoperative99mTc-HMPAO SPET can be used for the selection of patients in whom improvement in neurological status may be expected after urgent surgical correction of acute extracranial obstruction of the ICA.  相似文献   
82.
胸腰椎压缩性骨折的护理要点   总被引:2,自引:0,他引:2  
胸腰椎压缩性骨折的护理要点福建漳州市中医院(363000)郭燕玲,陈联源我院自1989年来对胸腰椎压缩性骨折实行辨证护理,收到满意效果,介绍如下。常规护理:屈曲型胸腰椎压缩性骨折,令病人仰卧在硬板床上,骨折处垫一软枕头,在耐受的情况下逐渐增加枕头高度...  相似文献   
83.
对我科1989-1990年中收治的婴儿肝炎综合征63例的临床表现、合并症、治疗等方面进行了分析。笔者认为婴儿肝炎综合征为一组临床症候群。病因诊断有其重要性。腹部B超检查有助于肝炎和胆道闭锁的鉴别,可作为常规检查方法。并认为用肾上腺皮质激素治疗有效。  相似文献   
84.
A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.  相似文献   
85.
Automatic analysis of electromyography (EMG) signals, first operated in 1950 with analogic machines, steeply expanded from 1980 when fast computers and worthwhile programs became available. On-line measurement of response area and latency, averaging of low amplitude waves, fast sorting of motor unit potential shape parameters, computation of the “jitter” between two muscle fibers, turns/amplitude and spectral analysis of interferential pattern records, are some examples of programs currently offered in modern EMG machines. Other techniques are still reserved for research purposes: scanning EMG, decomposition of nerve and muscle compound potentials, measurement of the threshold and firing rate of motor units, trace analysis using tracking models. Finally, the credit for artificial intelligence systems (knowledge based systems, fuzzy logic, neuronal networks) is still not clearly stated.  相似文献   
86.
Single trial amplitude, latency jitter, and electroencephalographic (EEG) power were examined as sources of the group difference in averaged P300 amplitude among 15 traumatically brain injured and 20 control individuals in an auditory oddball paradigm. Mean amplitude of the individual trials was highly correlated with the amplitude of the averaged P300, with little additional unique variance attributable to latency jitter or EEG power. The group difference in P300 amplitude was also explained by the mean amplitude of the single trials. These results support the robustness of the event-related potential averaging technique within the paradigm used.  相似文献   
87.
Summary Allotransplantation of solid organs transfers passenger leucocytes which may give rise to a state of persistent microchimaerism. In this report we describe the case of a patient who developed a solitary plasmacytoma in a transplanted kidney more than 10 years after allografting. The diagnosis was established on the basis of the presence of a monoclonal IgG kappa peak in the serum, and light chain proteinuria, the plasmacytoid features of tumour cells including cell surface expression of IgG, kappa light chains, CD20, CD38 and CD56, the absence of lytic bone lesions and a normal bone marrow biopsy, and the disappearance of the monoclonal IgG peak after graft nephrectomy. A donor origin of the tumour was established by HLA DNA typing of tumour, tumour-free kidney tissue, and peripheral blood leucocytes, respectively.  相似文献   
88.
89.
Guthrie and Buchwald (1991) proposed an ad hoc procedure for assessing the statistical significance of waveform difference potentials that may arise in a variety of psychophysiology research contexts. In our paper, an alternative method is presented and demonstrated that has fewer underlying assumptions than does the Guthrie-Buchwald test and may, therefore, produce better results in some situations. In particular, the test proposed here (a) is distribution free, (b) requires no assumption of an underlying correlation structure (e.g., first-order autoregressive), (c) requires no estimate of the population autocorrelation coefficient, (d) is exact, (e) produces p values for any number of subjects and time points, and (f) is highly intuitive as well as theoretically justifiable. This procedure may be used to carry out multiple comparisons with exact specification or experimentwise error, however, this test is based on permutation principles and may require large amounts of computer time for its implementation.  相似文献   
90.
采用计算机图象纹理分析和相关点阵检测技术,对人食管正常粘膜、不典型增生上皮及原位癌的不同纹理特征进行了观察。观察样品为常规病理切片,用计算机图象分析系统检测了组织的纹理特征。对受检图象建立了三种灰色分层关系矩阵,同时计算了8种纹理测度。结果显示,在重度不典型增生上皮和原位癌之间,其纹理测度和相关点阵检测数据均有显著性差异(P<0.05)。全部测量数据经计算机多元逐步判别分析,其正判率达90%以上。本研究结果表明,计算机纹理分析方法可正确地判别食管癌前病变和原位癌的组织结构异型性。提示本技术在食管癌的早期诊断方面具有肯定的实用性价值。  相似文献   
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