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61.
62.
Objectives. The aetiology of orofacial pain (OFP) is not well understood. We aimed to determine the relationship between OFP and local mechanical factors in an unselected general population sample.

Methods. A cross-sectional population-based survey was conducted in the United Kingdom, involving 2504 participants (adjusted participation rate 74%). Postal questionnaire was used to collect information on OFP and local mechanical factors.

Results. A significant association was found between OFP and a history of tooth grinding, facial trauma, the jaw getting stuck or locked, a clicking or grating sound in the jaw joint when opening or closing the mouth, difficulty in opening the mouth wide, and chewing of pens or biting finger nails. The jaw getting stuck or locked had the highest relative risk of 2.7 (95% CI: 2.3–3.2). A history of orthodontic treatment, having any type of dentures and using chewing gum were not associated with OFP. There was some evidence of heterogeneity between types of OFP and local mechanical factors.

Conclusions. Local factors play an important role in the aetiology of OFP.  相似文献   

63.
BACKGROUND: The present study was undertaken to test the effectiveness of an established equation for estimating the probability of acute cardiac ischaemia, but in an environment different from that in which it was developed. METHODS AND RESULTS: A total of 255 patients who presented to the accident and emergency department of Glasgow Royal Infirmary with symptoms suggesting acute ischaemic heart disease were enrolled in the study. Their clinical data and ECG measurements were used as input to the Time-Insensitive Predictive Instrument (TIPI) equation to calculate the probability of acute myocardial ischaemia being present. Receiver operating characteristic (ROC) curves were derived to evaluate the usefulness of the equation in diagnosing acute myocardial infarction versus nonmyocardial infarction and acute cardiac ischaemia verses nonischaemic chest pain. For the diagnosis of acute cardiac ischaemia versus noncardiac chest pain, the area under the ROC curve was 0.61 (95% CI 0.55-0.67). For the diagnosis of acute myocardial infarction versus nonmyocardial infarction, there was increased performance with the area under the ROC curve being 0.71 (95% CI 0.65-0.76). This compares with the originally published findings of a value of 0.88 for the area under the curve for the diagnosis of acute myocardial ischaemia versus noncardiac chest pain. CONCLUSION: The study suggests that equations for the diagnosis of acute cardiac ischaemia developed in one centre may not readily translate elsewhere, possibly due to varying interpretations of the clinical and ECG criteria used.  相似文献   
64.
Measurement of respiratory rate (RR) is essential in the evaluation of respiratory disorders. However, the variability in RR measurement in adults has never been adequately assessed. Respiratory rate was measured twice in 245 patients; the two measurements were performed by the same observer in 137 patients, by different observers in 58 patients and simultaneously by different observers in 50 patients.The mean (SD) difference between the first and second measurements was 0.03 (3); 95% limits of agreement-4.86-4.94 breaths min(-1), -5.7-5.7 breaths min(-1), and -4.2 to 4.4 breaths min(-1) for the same observer, different observer and simultaneous observer groups, respectively. The difference in RR measurements did not vary with RR. In conclusions on average, there is very good agreement between observers in RR measurement. Inter-observer variability may account for a difference of up to 6 breaths min(-1). This is relevant when applying clinical prediction rules based on threshold RR values.  相似文献   
65.
This study examined the safety of adding 153Sm lexidronam to standard conditioning regimens in patients undergoing stem cell transplantation for marrow based haematological malignancies in whom total-body irradiation as part of conditioning was desirable but not feasible. Ten such patients were enrolled, seven with multiple myeloma. An escalating regimen of 19-45 GBq of 153Sm lexidronam was added 12-14 days prior to the standard transplantation regimen. Evaluation parameters included time to engraftment, status at day +100 by International Bone Marrow Transplant Registry (IBMTR) criteria and toxicity during this period. Absorbed marrow radiation doses were estimated using the MIRDOSE 3 program. No adverse events were attributable to 153Sm lexidronam. Of the seven patients with multiple myeloma, four achieved complete response, two partial response, and another had stable monoclonal band at 3 months post-transplant. One patient with Refractory Anaemic with Excess Blasts in transformation (RAEBt) died of a presumed fungal infection, whilst another with acute myeloid leukaemia relapsed, dying at day +153. A patient with low-grade lymphoma showed no evidence of residual disease at day +100. The total marrow absorbed dose was estimated to be 0.7+/-0.2 mGy x MBq(-1). Regional uptake was markedly non-uniform with poor uptake in the appendicular skeleton. Dose-limiting toxicity was not attained. At the activities used 153Sm lexidronam was not associated with additional toxicity in this population. Adequate absorbed radiation dose to appendicular marrow is unlikely to be deliverable by this approach alone.  相似文献   
66.
Standard treatment regimens for haematological malignancies include myeloablative chemoradiotherapy and subsequent rescue by stem cell transplantation. However, these treatment regimens have significant associated mortality and morbidity, and disease recurrence remains a problem. One alternative approach is the targeted delivery of radiotherapy to the marrow using a bone-seeking agent labelled with an appropriate radioisotope, with the aim of delivering a potentially ablative radiation dose to marrow while minimising non-haematological toxicity. Pharmacokinetics and radiation dosimetry for a commercial preparation of samarium-153 ethylene diamine tetramethylene phosphonate (EDTMP; Quadramet) were evaluated in 43 tracer (average dose 740 MBq) studies of 42 patients with haematological malignancies. Measurements of 24-h retention were also available following infusion of 18-48 GBq in 15 patients. Quadramet cleared rapidly from the tissue, with a median biological half-life of 1.4 h. Activity taken up by the skeleton was firmly bound, with activity decreasing according to physical half-life at 24 h in 29 of the 43 cases. The percentage activity retained in the skeleton at 24 h with tracer doses was high (62%+/-13%), although this decreased to approximately 30% with therapy infusions. Because of this decrease in retention, the maximum feasible therapy activity for this formulation of Quadramet is 35 GBq. Median absorbed marrow radiation dose was 0.78 Gy/GBq in tracer studies: the decreased retention at high activities means that this corresponds to a median dose of 12 Gy for 35 GBq administered activity. It is possible to use 24-h retention as a rough guide to marrow dose in individual patients. In tracer studies, median bladder radiation dose was 0.22 Gy/GBq and radiation dose to the liver was very conservatively estimated at 0.2 Gy/GBq. After therapy infusions of up to 50 GBq in 37 patients, non-haematopoietic toxicity was not seen in any patient. In addition, myelosuppression was achieved without evidence of myelofibrosis. The residual dose rate to marrow fell to a level acceptable for stem cell re-infusion by 2 weeks after administration.  相似文献   
67.
It has been estimated that over 80% of the population will report low back pain (LBP) at some point in life, and each year 7% of the adult population consult their GP with symptoms. Prevalence increases with age, reaching a peak during the sixth decade of life. Until recently little was known about LBP at young ages. Clinically it was perceived to be uncommon-with few children consulting because of LBP in primary care. Large prospective epidemiological studies have shown that, in those free of LBP at baseline, the best predictor of future onset is a previous history of LBP. Therefore, to understand the epidemiology of LBP, and what predisposes someone to a trajectory of LBP in adult life, it is important to examine the condition at young ages, to determine factors responsible for onset of initial episodes, and to examine whether LBP in childhood is related to symptoms in adulthood.  相似文献   
68.
The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings.  相似文献   
69.
70.
Few case-control studies have examined possible risk factors for diarrhoeal deaths in under-age-five children in the developing countries. We analysed data from the surveillance system of our diarrhoea treatment centre/hospital for the period 1990-94 on 928 children less than 5 years of age. In univariate analysis, 11 factors were significantly associated with death: lack of breastfeeding, severe malnutrition, complicated diarrhoea, pneumonia, xerophthalmia, duration of diarrhoea 7-14 days, moderate or severe dehydration, recent history of measles, Shigella flexneri infection, maternal illiteracy, and very low household income. Rotavirus diarrhoea was negatively associated with fatal outcome. In the assessment of severe malnutrition, weight-for-height measurement discriminated mortality risk better than weight-for-age or height-for-age indices. Only two factors retained their significance, severe malnutrition and non-breastfeeding in the multivariate analysis with adjusted odds ratio (95% confidence interval) of 84.2 (9.1, 775.9) and 4.2 (1.3, 13.2) respectively.  相似文献   
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