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OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.  相似文献   
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Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

Methods

In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.

Results

There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.

Conclusions

The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction.  相似文献   
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Congenital deafness is a relatively frequent disorder that shows a heterogeneous aetiology. Knowledge and the control of some risk factors have decreased the incidence of acquired deafness and increased the relative importance of genetic cause. In an attempt to investigate the clinical relevance of congenital deafness and the mechanisms of prevention in our population, a clinical and genetic study of cases with neurosensorial deafness born in Navarra between 1975 and 1990 was carried out. A total of eighty-one cases were identified, giving an incidence of 0.8 per thousand. Thirty per cent of the cases showed deafness associated with defects. Cause of deafness was identified in seventy per cent of the cases with whom a detailed clinical and genetic study could be performed (n=50). Genetic factors were responsible for the disorder in more than half of these cases. The most frequent hereditary factor was of the autosomic recessive type. This was associated with a more severe form of hearing loss.  相似文献   
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Arachnoid cysts situated in the middle cranial fossa constitute the largest group of this type of lesion. Their origin has been the subject of debate since they were first described. There is still controversy as to whether they originate directly from the meninges adjacent to the temporal pole or whether partial agenesis of the temporal lobe favours secondary formation of the cyst. We assessed the morphology of the temporal lobe and the bulging of the squamous temporal bone. Paradoxical changes in adjacent-bone, described as very rare findings in arachnoid cysts of the middle cranial fossa, were common in our study and suggest, in association with direct signs of temporal atrophy, that this atrophy precedes, or is at least coexistent with, the formation of the cyst. The importance of being able to determine the origin of the cyst lies in its being a factor to assess as regards treatment.  相似文献   
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Background

Sever acute malnutrition severely suppresses every component of the immune system leading to increased susceptibility and severity to infection. However, symptoms and signs of infections are often unapparent making prompt clinical diagnosis and early treatment very difficult. The aim of the study was to determine the magnitude of bacteraemia and antimicrobial sensitivity among severely malnourished children.

Methods

Severely malnourished children admitted in Jimma University Specialized Hospital were enrolled between October, 2009 to May, 2010. Blood samples were collected, processed and bacterial isolates were identified using standard bacteriological procedures. Then, antibiotic susceptibility pattern of the isolates was determined by using Kirby-Bauer technique.

Results

Bacteraemia was seen in 35 (20.6%) of the 170 study subjects. There were a total of 35 bacterial isolates, Gram positive bacteria constitute 24(68.6%) of the isolates, where Staphylococcus aureus was the leading Gram positive isolate while Klebsiella species were the dominant Gram negative isolates. Twelve (7.1%) children died and 4 (33.3%) of them had bacteraemia. While susceptibility was more than 80% to Gentamicin, Ciprofloxacin and Ceftriaxone, increased level of resistance was documented to commonly used antibiotics, such as Amoxycillin, Co-trimoxazole and Chloramphenicol.

Conclusion

High prevalence of bacteraemia with predominating Gram positive isolates and increased level of resistance to commonly used antibiotics was shown among severely malnourished children in Jimma. Further studies are required to revise the current guideline for antibiotic choice.  相似文献   
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In the context of physical and forensic anthropology, when a child’s skeleton is damaged or in poor condition, which is common, many of the metric methods for the estimation of skeletal age cannot be used. In these circumstances, those more resistant bones, such as the pars basilaris, will be most useful. The aims of this study were to test existing methods for estimating skeletal age from the metric study of the pars basilaris and to propose new regression formulae. One hundred fourteen individuals aged between 5 months of gestation and 6 years were analyzed; seven measures were taken from each pars basilaris using a digital caliper. The chronological age was compared with the estimated age using the methods published by Fazekas and Kósa in 1978 and by Scheuer and MacLaughlin in 1994. New regression formulae are proposed, obtained by classical calibration, which include confidence intervals at 50 and 97.5 % to express the error. With both methods, significant differences were observed; the method of Fazekas and Kósa shows a tendency to underestimate the age, and the method of Scheuer and MacLaughlin tends to overestimate it. The proposed formulae represent a good tool for estimating age in many different contexts because they are relatively easy to apply, although other analysis systems, such as Bayesian approach or geometric morphometry, offer more robust and effective results.

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The present study aimed to investigate the applicability of Universal Thermal Climate Index (UTCI) as an innovative and science-based index in public health researches, in occupational heat stress assessment. All indoor and outdoor workers (200 people) of Brick industries of Shahroud, Iran participated in the research. First, the environmental variables such as air temperature, wet-bulb temperature, globe temperature, air velocity and relative humidity were measured; then UTCI and WBGT (wet-bulb globe temperature) indices were calculated. Simultaneously, physiological parameters including systolic and diastolic blood pressure, oral temperature, skin temperature, tympanic temperature and heart rate of workers were measured. UTCI and WBGT indices were 34.2 ± 2°C, 21.8 ± 1.8°C in the outdoor environments and 38.1 ± 4.4°C, 24.7 ± 3.3°C at the indoor environments, respectively. There were the weak inverse relationships between UTCI and WBGT indices at the outdoor environments and physiological responses such as systolic blood pressure, and diastolic blood pressure. However, there were no similar results for indoor environments. The significant relationships were found between UTCI and WBGT at both indoor and outdoor environments. Both UTCI and WBGT indices are suitable for assessing the occupational heat stress. Although, UTCI index seems more appropriate for heat stress assessment in the environments with low humidity and air velocity.  相似文献   
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