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101.
Diffusion weighted imaging (DWI) and T2 weighted magnetic resonance imaging were performed on at least two occasions in 28 children presenting with stroke. In previous reports of DWI in human stroke, eventual infarction was observed (with only one exception) in all regions in which early DWI hyperintensity occurred. In the present report, two children had regions of DWI hyperintensity which did not progress to infarction. One patient who presented with right hemiplegia showed extensive high signal on DWI, with T2 evidence of tissue swelling but without hyperintensity. DWI changes persisted over weeks, with no imaging indication of infarction. This child recovered completely. A second child who had a major vessel infarct with concomitant regions of hyperintensity on T2 weighted imaging and DWI, also had DWI hyperintensity in an adjacent territory which did not develop any subsequent evidence of infarction. Thus in clinical practice DWI can demonstrate tissue which is compromised but not irreversibly so.  相似文献   
102.

Background  

Obesity is now a global epidemic. In this study, we aimed to assess the rates of obesity using several major diagnostic criteria in Chinese school adolescents in Hong Kong.  相似文献   
103.
目的:探讨前列腺基底细胞增生的诊断及鉴别,以免误诊为癌。方法:选择原诊断有疑义的6 个中国病例,应用组织病理学和免疫组化标记方法观察。结果:没有不典型增生,5 例34βE12 全部强阳性。结论:此病变需与不典型增生、上皮内瘤、腺癌、腺病和腺体萎缩鉴别  相似文献   
104.

Background

Current guidelines for rehabilitation of arm and hand function after stroke recommend that motor training focus on realistic tasks that require reaching and manipulation and engage the patient intensively, actively, and adaptively. Here, we investigated the feasibility of a novel robotic task-practice system, ADAPT, designed in accordance with such guidelines. At each trial, ADAPT selects a functional task according to a training schedule and with difficulty based on previous performance. Once the task is selected, the robot picks up and presents the corresponding tool, simulates the dynamics of the tasks, and the patient interacts with the tool to perform the task.

Methods

Five participants with chronic stroke with mild to moderate impairments (> 9 months post-stroke; Fugl-Meyer arm score 49.2 ± 5.6) practiced four functional tasks (selected out of six in a pre-test) with ADAPT for about one and half hour and 144 trials in a pseudo-random schedule of 3-trial blocks per task.

Results

No adverse events occurred and ADAPT successfully presented the six functional tasks without human intervention for a total of 900 trials. Qualitative analysis of trajectories showed that ADAPT simulated the desired task dynamics adequately, and participants reported good, although not excellent, task fidelity. During training, the adaptive difficulty algorithm progressively increased task difficulty leading towards an optimal challenge point based on performance; difficulty was then continuously adjusted to keep performance around the challenge point. Furthermore, the time to complete all trained tasks decreased significantly from pretest to one-hour post-test. Finally, post-training questionnaires demonstrated positive patient acceptance of ADAPT.

Conclusions

ADAPT successfully provided adaptive progressive training for multiple functional tasks based on participant's performance. Our encouraging results establish the feasibility of ADAPT; its efficacy will next be tested in a clinical trial.  相似文献   
105.

INTRODUCTION

Postoperative hypocalaemia commonly occurs after extensive thyroid surgery and may require calcium and/or vitamin D supplements to alleviate or prevent the symptoms. In this study, we determined the risk factors for developing hypocalcaemia and whether early serum calcium levels can predict the development of or differentiate between temporary or permanent hypocalcaemia.

PATIENTS AND METHODS

A total of 162 patients who either had a completion or total thyroidectomy formed the basis of this prospective study. Serial serum calcium measurements were recorded as well as details of the operation, pathology, indications for surgery, number of parathyroids identified at operation and any complications.

RESULTS

Eighty-four (52%) patients did not develop hypocalcaemia but 69 (43%) were found to have temporary hypocalcaemia and 9 (5%) had permanent hypocalcaemia. Hypocalcaemia was more common after total than completion thyroidectomies and the identification of parathyroids at operation appears to have a significant adverse effect on outcome. The calcium levels measured on day 1 postoperatively and the slope (serum calcium levels of day 1 postoperative minus day of operation) were statistically significant in predicting the development of hypocalcaemia and possibly to differentiate between temporary or permanent hypocalcaemia.

DISCUSSION

Although almost half the patients having extensive thyroid surgery developed hypocalcaemia (as defined by any postoperative corrected serum calcium level of < 2.12 mmol/l) only 24% had a serum calcium of < 2.12 mmol/l associated with clinical symptoms of hypocalcaemia or a calcium level of < 2.0 mmol/l. Only 5% had persistent hypocalcaemia defined as requiring exogenous supplements at 6 months'' postoperatively. Patients having a completion thyroidectomy appear to be less likely to develop hypocalcaemia perhaps as a result of any iatrogenic effects on the parathyroids at the first operation being reversed before the second operation. Identification and, therefore, exposure of parathyroids at operation may have an adverse effect on the blood supply to the glands affecting their function.

CONCLUSIONS

Serum calcium levels measured 6 hours'' post-surgery and on day 1 postoperatively can be useful in predicting if the patient will develop hypocalcaemia and the slope may indicate whether the hypocalcaemia will be temporary or permanent. Patients with toxic goitres and those having a one-stage total thyroidectomy are most at risk of developing hypocalcaemia.  相似文献   
106.
107.
The aim of the study was to identify risk factors associated with increased risks of post Caesarean febrile morbidity from a retrospective epidemiological analysis, and to prospectively evaluate a protocol of selective antibiotic prophylaxis based on these risk factors. Caesarean section births over a three-year period--during which no antibiotic prophylaxis protocol was practised--were reviewed. Risk factors for febrile morbidity were identified using both univariate and multivariate analysis. A protocol of selective antibiotic prophylaxis, incorporating the significant risk factors identified, was then evaluated prospectively over a nine-month period. The incidence of febrile morbidity from the retrospective study was 16.9%. A logistic regression model, with febrile morbidity as the dependent variable, identified only the duration of labour over 10 hours as a significant factor. A protocol of antibiotic prophylaxis using intravenous ampicillin was then practised in the presence of these two factors. Evaluation of this protocol after nine months showed that the incidence of febrile morbidity was reduced significantly from 20% in those not given antibiotics to around 9.6% in those eligible for and given antibiotics. However, the overall incidence of febrile morbidity remained at around 16-18%.  相似文献   
108.
A technique for the culture of Barrett's oesophageal cells   总被引:2,自引:0,他引:2  
Establishment of cells in tissue culture from Barrett's columnar epithelium has been difficult. The aim of this study was to develop a successful tissue culture method employing a serumfree medium for cultivation of Barrett's epithelial cells. Fragments of Barrett's mucosal tissue were explanted in a 3:1 mixture of Dulbecco's modification of Eagle's medium and Ham's F12, to initiate the outgrowth of epithelial cells. Subsequently, a commercial serum-free medium (formulated for the growth of keratinocytes) was used for the propagation of Barrett's oesophagus cells without fibroblast growth. Cells established in culture retained their epithelial morphology, stained positive for cytokeratin, and contained Alcian blue (pH 2.5) and periodic acid-Schiff reagent-positive/diastase-resistant vacuoles, confirming their origin from Barrett's epithelium. Electron microscopy showed tonofilaments, microvilli and desmosomes. Coating the surface of culture vessels was not required and four cell strains could be passaged up to 20 times with no fibroblast growth, in the keratinocyte serumfree medium.  相似文献   
109.
We investigated the expression of cartilage oligomeric matrix protein (COMP) in normal and rheumatoid arthritis (RA) synovial fibroblasts. In situ hybridization (ISH) was conducted on synovial specimens from five RA patients applying specific probes for COMP or fibroblast collagen type I. ISH was combined with immunohistochemistry, applying antibodies to the macrophage marker CD68. Ribonuclease protection assay (RPA) and rapid amplification of 3'-cDNA ends (3'-RACE) were performed on total RNA from normal and RA synovial fibroblast cultures. Protein extracts from fibroblasts and culture supernatants were compared with synovial fluids and protein extracts from isolated chondrocytes by Western blot utilizing polyclonal and monoclonal antibodies (18-G3 mAb) to COMP. COMP mRNA was detected in fibroblasts of RA synovium by ISH, and in normal and RA synovial fibroblast cultures by RPA. 3'-RACE demonstrated sequence homology of chondrocyte and synovial fibroblast COMP along the coding sequence. COMP protein was detected in synovial fibroblasts and culture supernatants by immunoblot. Using polyclonal antibodies, the major portion of COMP from fibroblasts and culture supernatants was present as low-molecular-weight (LMW) bands, corresponding to those found in synovial fluids. These LMW COMP bands, however, were not detected in any of the cells or tissues tested using 18-G3 mAb. In protein extracts from chondrocytes and in COMP purified from cartilage, these LMW bands could not be detected. In conclusion, the data suggest that certain forms of COMP detected in synovial fluid are secreted from synovial fibroblasts and could be distinguished by specific mAbs from COMP secreted by chondrocytes.   相似文献   
110.
Objective : To verify in a systematic study if the Chinese tradition of venerating older people results in lower suicide rates compared to other countries. Method : The ratio between suicide rates in the older population and total population were calculated and used to compare 40 countries. Results : The highest male suicide ratios in the world were found in Urban China, Singapore, Rural China and Hong Kong. Singapore, Urban China and Hong Kong had the worst female suicide ratios. The highest rate of suicide among females was in Rural China, which also had the highest suicide rate among older people. Conclusion : These findings raise questions about the adequacy of support to older Asian people. It is surprising that high suicide rates are found in Hong Kong, Korea, Japan and Singapore, which are affluent societies. The possibility of this being the result of ageism is discussed. Country‐specific research is needed to improve suicide prevention measures, especially for older people.  相似文献   
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