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排序方式: 共有1902条查询结果,搜索用时 15 毫秒
1.
Josh Greenstein Devjani Das Josie Acuna Monica Kapoor Cara Brown Abbas Husain Brendan Lally Barry Hahn 《The American journal of emergency medicine》2019,37(2):313-316
Background
In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.Objectives
The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.Methods
This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.Results
A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.Conclusions
In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation. 相似文献2.
3.
John P Norvell Andres T Blei Borko D Jovanovic Josh Levitsky 《Liver transplantation》2007,13(10):1428-1434
Hepatitis is a rare complication of herpes simplex virus (HSV), often leading to acute liver failure (ALF), liver transplantation (LT), and/or death. Our aim was to identify variables associated with either survival or progression (death/LT), based on an analysis of cases in the literature and our institution. A total of 137 cases (132 literature, 5 institutional) of HSV hepatitis were identified. The main features at clinical presentation were fever (98%), coagulopathy (84%), and encephalopathy (80%). Rash was seen in less than half of patients. Most cases (58%) were first diagnosed at autopsy and the diagnosis was suspected clinically prior to tissue confirmation in only 23%. Overall, 74% of cases progressed to death or LT, with 51% in acyclovir-treated patients as compared to 88% in the untreated subjects (P=0.03). Variables on presentation associated with death or need for LT compared to spontaneous survival: male gender, age>40 yr, immunocompromised state, ALT>5,000 U/L, platelet count<75x10(3)/L, coagulopathy, encephalopathy, and absence of antiviral therapy. In conclusion, HSV hepatitis has a high mortality and is often clinically unsuspected. Patients who are male, older, immunocompromised, and/or presenting with significant liver dysfunction are more likely to progress to death and should thus be evaluated for LT early. Based on the frequent delay in HSV diagnosis, low risk-benefit ratio, and significantly improved outcomes, empiric acyclovir therapy for patients presenting with ALF of unknown etiology is recommended until HSV hepatitis is excluded. 相似文献
4.
We investigated the effects of hypercalcemia on pancreatic duct permeability and pancreatitis in cats. Acute hypercalcemia was maintained by an infusion of calcium gluconate; controls received saline solution. Chronic hypercalcemia was maintained by diet and by vitamin D and dihydrotachysterol injections. Portal venous blood was analyzed for large dextran molecules that had been perfused through the pancreatic duct. In a separate group of hypercalcemic animals, we perfused the duct with activated pancreatic enzymes to induce acute pancreatitis. After 24 hours of hypercalcemia, dextrans were detected in the portal venous blood of 6 of 11 hypercalcemic and none of the 6 control animals (p less than 0.05). After 12 hours of hypercalcemia, dextrans were detected in all 7 hypercalcemic and 1 of 7 control animals (p less than 0.001). The degree of pancreatic inflammation was greater in the 12-hour animals than in the controls (p less than 0.001). After 14 days of hypercalcemia, however, there were no differences in dextran permeability or pancreatitis in experimental or control animals. Our results indicate that acute hypercalcemia increases the permeability of the pancreatic duct to molecules the size of pancreatic enzymes. This could be important in the pathogenesis of acute pancreatitis associated with hypercalcemic states. 相似文献
5.
Josh W. McDonald Victor L. Roggli William D. Bradford 《Fetal and pediatric pathology》1994,14(3):505-511
We report a unique case of coexistingexogenous lipoid pneumonia, endogenous lipoid pneumonia (EU), and pulmonary alveolar proteinosis (PAP) in a 5-year-old patient with severe neurodevelop mental disease. The patient presented with gastroesophageal reflux and presumed chronic lung disease resulting from recurrent aspiration pneumonias and succumbed to respiratory failure. The autopsy showed lipid-laden macrophages and periodic acid-SchiJf9ositive granular matm'al i n alveolar spaces and multilamellated structures within both alveolar macrophages and extracellular debris.
These findings were similar to those in previous reports of coexisting E I P and PAP in the setting of gastroesophageal refux [I] . However, the present case diJfered by the presence of scattered large osmiophilic extracellular lipid vacuob. Besides strengthening the association between EIP and PAP and their relationship to gastroesophageal refux, this case suggests that t h q may arise together with exogenous lipoid pneumonia, through related mechanisms, in the setting of neurodevelopmental disease. 相似文献
These findings were similar to those in previous reports of coexisting E I P and PAP in the setting of gastroesophageal refux [I] . However, the present case diJfered by the presence of scattered large osmiophilic extracellular lipid vacuob. Besides strengthening the association between EIP and PAP and their relationship to gastroesophageal refux, this case suggests that t h q may arise together with exogenous lipoid pneumonia, through related mechanisms, in the setting of neurodevelopmental disease. 相似文献
6.
Genevieve Fridlund Dunton Carol K. Whalen Larry D. Jamner Josh N. Floro 《Annals of behavioral medicine》2007,34(2):144-153
BACKGROUND: Research has sought to understand how environmental factors influence adolescent physical activity, yet little is known about where and with whom adolescents are physically active. PURPOSE: This study used electronic ecological momentary assessment (e.EMA) to map the social and physical contexts of exercise and walking across adolescence. Differences in physical activity contexts by gender, grade in school, day of the week, and season were examined. METHODS: Twice a year between 9th and 12th grade, 502 adolescents (51% female) of mixed ethnicity (55% White) participated in 4-day e.EMA intervals (Thursday-Sunday) where their primary activity (e.g., exercise, TV, homework), social company (e.g., friends, family, class), and physical location (e.g., home, school, outdoors) were assessed every 30 (+/-10) min during waking hours. RESULTS: Overall, greater proportions of exercise and walking were reported with friends, outdoors, and at school. However, boys were more likely to report exercising and walking in outdoor locations than girls. Exercising with classmates, family, and at school decreased across high school. Walking with family, friends, and outdoors also decreased. On weekdays compared to weekends, students reported a greater proportion of their exercise and walking at school. Students were more likely to report exercising and walking outdoors in the fall and the spring than in the winter. CONCLUSION: e.EMA showed that the social and physical contexts of adolescent exercise and walking vary as a function of gender, grade in school, day of the week, and season. Understanding the contexts of physical activity during the high school years can be helpful in designing interventions during adolescence. 相似文献
7.
Field Tiffany; Hernandez-Reif Maria; Seligmen Susan; Krasnegor Josh; Sunshine William; Rivas-Chacon Rafael; Schanberg Saul; Kuhn Cynthia 《Journal of pediatric psychology》1997,22(5):607-617
Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities 相似文献
8.
Rats with lesions of the area postrema (APX) are known to exhibit an enhanced intake of highly palatable foods such as sweetened condensed milk and cookies. These observations suggest the possibility that APX rats find these foods more rewarding and will work harder to obtain these foods. Sham and APX rats were tested on fixed ratio (FR) and progressive ratio (PR) schedules. APX rats consistently pressed more times to receive sucrose solution and attained both FR 3 and FR 5 criteria significantly faster than sham-lesioned control rats. Furthermore, rats with APX had significantly higher break points than sham-lesioned control rats on a progressive ratio schedule. These results support the hypothesis that rats with lesions of the area postrema will consistently work harder to obtain a highly palatable food reward. 相似文献
9.
10.
F J Buckwold A R Ronald G K Harding T J Marrie L Fox C Cates 《Journal of clinical microbiology》1979,10(3):275-278
A nine-test system using multiple-inoculation agar plates for biotyping of Escherichia coli is described. Testing of 959 strains resulted in 78 biotypes. On repeated testing, 96% of 182 strains had identical biotypes or differed by only one test. This system provides satisfactory differentiation among strains and is reproducible. Precise standardization of inoculum size is not required. Multiple inoculation allows time and cost-efficient testing of large numbers of strains. 相似文献