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91.
In 2007, an epizootic of equine influenza (EI) occurred in Australia, involving parts of the states of Queensland and New South Wales. Following an extensive control program, the disease was eradicated within 4 months, after infecting more than 75 000 horses on over 10 000 properties. In Queensland, examination of land use patterns revealed that the majority of infected premises (89.5%) were located in one of three land use classes viz. rural residential, residential‐unspecified or grazing natural vegetation. All nine clusters of infection in Queensland were surrounded to some degree by parcels of land whose designated use precluded the presence of horses. In four clusters, these horse‐free areas completely enclosed the cluster and spread was limited to a relatively small area whereas the remaining five clusters were not completely surrounded by horse‐free buffers and spread was much more extensive. The cumulative incidence of infection with EI dropped from 41% of properties in rural‐residential areas to 4% of properties located further than 5 km from rural‐residential areas. This decrease was associated with a 10‐fold increase in the median size of properties and a 5‐fold decrease in the density of horses on those premises. There was a strong negative correlation between the cumulative incidence of infection and the median property size (R = −0.91, P < 0.05) and a positive correlation with the horse density on those properties (R = 0.93, P < 0.01).  相似文献   
92.
93.
白旭  张云亭 《医学影像学杂志》2008,18(12):1345-1349
目的:探讨颅内神经元及混合性神经元-神经胶质肿瘤的MRI表现特征,以提高对其认识和诊断水平。方法:复习22例经手术病理证实的神经元及混合性神经元-神经胶质肿瘤的临床和影像资料,结合文献分析其MRI表现特征。结果:5例中枢神经细胞瘤均位于侧脑室内,呈不均匀长T1、长T2信号和不均匀强化;1例神经节细胞瘤位于颞叶,呈长T1、长T2信号,无瘤周水肿和强化;12例神经节细胞胶质瘤中,6例在颞叶,5例为囊性并有强化壁结节;2例胚胎发育不良性神经上皮肿瘤均位于颞叶皮质,呈不均匀长T1、长T2信号,无瘤周水肿和强化;1例婴儿促纤维增生性神经节细胞胶质瘤位于颞叶皮质,为不均匀长T1和一致性长T2信号,无瘤周水肿,呈环状强化;1例乳头状胶质神经元肿瘤在颞叶,呈囊性并有不规则壁结节,其囊壁和壁结节发生强化。结论:MRI检查,不同类型的神经元及混合性神经元-神经胶质肿瘤各具其好发部位并多有一定表现特征,结合患者年龄和临床表现,常可做出倾向性诊断。  相似文献   
94.
PURPOSE: To apply diffusion tensor images using 30 noncollinear directions for diffusion-weighted gradient schemes to characterize diffusion tensor imaging (DTI) features associated with C6 glioma-bearing rat brains, and ideally visualize fiber tractography datasets. MATERIALS AND METHODS: Fiber tractographies of normal male Fischer 344 rat brains were constructed from DTI datasets acquired with a 30 noncollinear diffusion gradient scheme. Cultured C6 cell were intracranially injected into the cortex of male Fischer 344 rats. The time course of the tumor growth was monitored with DTI and fiber tractography using diffusion-weighting gradients in 30 noncollinear directions. RESULTS: Fiber tractographies through the corpus callosum (CC) were easily visualized with the 30-direction gradient scheme, and the fiber trajectories of the motor cortex and striatum were well represented in normal rats. Fiber tractography indicated that the neuronal fibers of the CC were compressed or disappeared by growing C6 glioma, which affected surrounding brain tissue. CONCLUSION: We have demonstrated in this study that fiber tractography with the 30 noncollinear diffusion gradient scheme method can be used to help provide a better understanding regarding the influence of a tumor on the surrounding regions of normal brain tissue in vivo.  相似文献   
95.
BACKGROUND: Previous sentinel lymph node (SLN) studies for cutaneous melanoma have shown that the SLN accurately reflects the nodal status of the corresponding nodal basin. However, there are few long-term studies that describe recurrence site patterns, predictors for recurrence, and overall survival and disease-free survival after SLN biopsy. METHODS: A retrospective review of patients over a 6-year period was performed to determine patient outcomes and the patterns of recurrence. In all cases, Tc-99 sulfur colloid along with isosulfan blue dye was injected at the primary melanoma site. After resection, the SLN was serially sectioned and evaluated by hematoxylin and eosin staining and immunohistochemistry. RESULTS: One hundred ninety-eight patients were identified who underwent SLN biopsy for cutaneous melanoma including T1 (n = 21), T2 (n = 88), T3 (n = 75), and T4 (n = 14) primary tumors. Of these patients, 38 had a positive SLN. Of the 38 patients with a positive SLN (mean follow-up 38 months), recurrent disease was identified in 10 (26.3%) at a mean interval of 14.2 months. The site of first recurrence was distant (n = 4) and local (n = 6). Regional lymphatic basin recurrence was not identified. Of the 160 patients with a negative SLN (mean follow-up 50 months), recurrent disease was identified in 16 (10.0%) at a mean interval of 31.3 months. The site of first recurrence was systemic (n = 11), local (n = 4), and nodal (n = 1). Overall survival and disease-free survival for patients with a positive SLN at 55 months was 53.3% and 47.7% respectively, while overall survival and disease-free survival for patients with a negative SLN at 53 months was 92.2% and 87.7% respectively (P <0.01). Univariate and multivariate analysis of the entire cohort (n = 198) identified primary tumor depth and positive SLN status as significant predictors of recurrence. CONCLUSIONS: The incidence of nodal basin recurrence after SLN biopsy was found to be 0.6%. Primary tumor depth and pathological status of the SLN are significant predictors of local and systemic recurrence. Long-term follow-up indicates that patients with a positive SLN clearly recur sooner and have decreased overall survival than those with a negative SLN.  相似文献   
96.
目的观察咳嗽并见背冷症患者的临床表现及中医证候特点,探讨分析其病因病机,为咳嗽的临床诊疗提供依据。方法选取以"咳嗽"为主诉且并见背冷症的患者作为研究对象,就其一般性资料、所患呼吸系统基础疾病、咳嗽及背冷症发生的临床特点、相关因素进行分析,总结其发病特点、病因病机及证候学特点。结果咳嗽并见背冷症临床常见,背冷症与咳嗽症状密切相关,病理要素包含湿热、阳虚、痰饮、风邪等。中医辨证分型可见脾胃湿热证占22.8%、脾胃湿热证兼肺阳虚证占21.3%、肺阳虚证占17.3%、肺脾阳虚证占12.7%等。结论背冷症与咳嗽常相兼而见,可见于不同年龄段、不同肺系疾病中,轻重程度各异,且与季节、气候变化等有关。脾胃湿热证、肺阳虚证及其相兼证为咳嗽并见背冷症的常见证候,湿热邪气阻滞气机及肺脾阳虚、卫阳失布而致肺失宣肃是主要病机。  相似文献   
97.
BACKGROUND: Penetrating trauma injury is generally associated with higher short-term mortality than blunt trauma, and results in substantial societal costs given the young age of those typically injured. Little information exists on the patient and treatment characteristics for penetrating trauma in England and Wales, and the acute outcomes and costs of care have not been documented and analysed in detail. METHODS: Using the Trauma Audit Research Network (TARN) database, we examined patient records for persons aged 18+ years hospitalised for penetrating trauma injury between January 2000 and December 2005. Patients were stratified by injury severity score (ISS). RESULTS: 1365 patients were identified; 16% with ISS 1-8, 50% ISS 9-15, 15% ISS 16-24, 16% ISS 25-34, and 4% with ISS 35-75. The median age was 30 years and 91% of patients were men. Over 90% of the injuries occurred in alleged assaults. Stabbings were the most common cause of injury (73%), followed by shootings (19%). Forty-seven percent were admitted to critical care for a median length of stay of 2 days; median total hospital length of stay was 7 days. Sixty-nine percent of patients underwent at least one surgical procedure. Eight percent of the patients died before discharge, with a mean time to death of 1.6 days (S.D. 4.0). Mortality ranged from 0% among patients with ISS 1-8 to 55% in patients with ISS>34. The mean hospital cost per patient was pound7983, ranging from pound6035 in patients with ISS 9-15 to pound16,438 among patients with ISS>34. Costs varied significantly by ISS, hospital mortality, cause and body region of injury. CONCLUSION: The acute treatment costs of penetrating trauma injury in England and Wales vary by patient, injury and treatment characteristics. Measures designed to reduce the incidence and severity of penetrating trauma may result in significant hospital cost savings.  相似文献   
98.
Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections.  相似文献   
99.
Deakin DE  Crosby JM  Moran CG  Chell J 《Injury》2007,38(11):1241-1246
INTRODUCTION: Fractures account for significant morbidity during childhood. Children requiring inpatient management for their fractures represent the most serious injuries. The aim of this study was to identify injury patterns in childhood fractures requiring inpatient management at a regional trauma centre. METHODS: Three thousand and forty two consecutive injured children were admitted to our orthopaedic centre over a 4-year period. Data was prospectively collected by independent audit clerks and entered onto a database. Data recorded included type of injury, mechanism of injury and place of injury. This was then used to assess injury patterns and trends. RESULTS: Upper limb and lower limb fractures accounted for 51% (n=1,565) and 21% (n=637) of all emergency admissions, respectively. Other causes included soft tissue injury, Infections, Polytrauma and Dislocations. Twice as many males were admitted with upper or lower limb fractures compared to females (67% versus 33%) (P<0.001). Males were more likely to be older (P<0.001) compared to females. Distal radial fractures accounted for 60% of upper limb fractures. Distal and midshaft tibial fractures accounted for 52% of lower limb fractures. Sports injuries were responsible for the majority of lower limb fractures with falls accounting for the majority of upper limb fractures. Fracture incidence peaked during summer months. CONCLUSION: Males are twice as likely to require inpatient management for fractures as females. Male adolescents are particularly at risk. Distal radial fractures following falls and distal tibial fractures following sports injuries are the most common fractures requiring admission. Identifying ways of minimising risk of these injuries would reduce childhood morbidity.  相似文献   
100.
《Neuro-Chirurgie》2021,67(6):579-586
BackgroundLiponeurocytoma is an uncommon tumor of the central nervous system. It is very rare for this tumor to originate within the lateral ventricle. In the context of the rarity of this tumor entity, this review article aims to summarize the clinical, radiological, and pathological features of lateral ventricular liponeurocytoma to facilitate its diagnosis and management.MethodsHere, we conduct a systematic literature review using the Pubmed, Scopus, and Cochrane Library database for all cases of lateral ventricular liponeurocytoma. A case illustration complements this review.ResultsThe described cases from 1997 onward include 14 cases that have been published in full papers in the English literature. Six additional cases are reported in short English abstracts in full non-English papers, and one case was described in a central neurocytoma report. There is a definite male predominance of 70% (14 male) and a mean age of 37 years (range 24–62). Heterogenous enhancement and signals in magnetic resonant images (MRI) are the radiological characteristics. In all reported cases, the presence of lipocytes and fat vacuoles is considered the paramount histopathological feature. Total surgical resection was achieved in 80% (12 out of 15) of the cases. Only two cases (including ours) received radiation therapy. Recurrence was seen in two patients during follow-up that was treated by radiation therapy in one and surgery in the other. The proliferation index is mostly below 5% in all cases, with the Ki-67 range between < 1% to 10%.ConclusionsLateral ventricular liponeurocytoma has been treated effectively by surgical resection in a limited number of cases. The decision for radiation therapy is based on a high proliferation index and tumor recurrence.  相似文献   
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