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51.
Richard J Levy Whitney B Stern Kimberly I Minger Lisa M Montenegro Chitra Ravishankar Jonathan J Rome Susan C Nicolson David R Jobes 《Pediatric critical care medicine》2005,6(6):671-675
BACKGROUND: Mixed venous saturation (S & OV0456;o2) is an important measurement that helps guide the care of critically ill patients. Invasive S & OV0456;o2 assessment in infants and children is often avoided because of the inherent risks. A noninvasive tissue saturation (S to 2) monitor has recently been developed that uses near-infrared spectroscopy to measure oxyhemoglobin saturation in muscle. In adult and animal studies, S to 2 correlated with oxygen delivery and S & OV0456;o2. There has been no evaluation in pediatric patients. OBJECTIVE: To evaluate tissue saturation as a noninvasive measure of mixed venous saturation in children. DESIGN: A prospective observational study. SETTING: Catheterization laboratory in a tertiary care children's medical center. PATIENTS: We studied 98 children (49 without intracardiac mixing and 49 with intracardiac mixing) 相似文献
52.
Assault-injured Adolescents Presenting to the Emergency Department: Causes and Circumstances 总被引:1,自引:0,他引:1
53.
Hao Wu Colin Webber Carmen Otero Fuentes Robert Bensen Karen Beattie Jonathan D Adachi Xiaoming Xie Farhang Jabbari David R Levy 《Journal l'Association canadienne des radiologistes》2007,58(3):167-175
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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Effects of Ethanol Exposure during the Third Trimester Equivalent on Neuron Number in Rat Hippocampus and Dentate Gyrus 总被引:5,自引:0,他引:5
James R. West PhD Kristin M. Hamre BA Martin D. Cassell PhD 《Alcoholism, clinical and experimental research》1986,10(2):190-197
An artificial rearing procedure was used to expose neonatal rats to a formula containing 3.74% ethanol during postnatal days 4 through 10. This treatment produced a mean blood ethanol concentration of 379.8 +/- 17.3 mg/dl. When the pups were killed on the afternoon of postnatal day 10, brain weight to body weight ratio in the ethanol-exposed rats was reduced 22.4% and 21.5% compared to suckle and pair-fed controls, respectively. Ethanol exposure also resulted in a 16% reduction of neurons in hippocampal field CA4, compared to controls, but did not produce deficits in fields CA1 or CA3. There was also a 10% increase in the number of neurons (a population of cells in the midst of a proliferative phase at the time of the exposure) in the granule cell layer of the dentate gyrus. The ethanol exposure did not affect cell size in any of the four neuron populations measured. These results suggest, that within the dose and timing parameters examined, ethanol exposure during the third trimester equivalent appears to be preferentially harmful to specific populations of developing neurons. 相似文献
56.
Radhika Jaladi William K Levy Paul V Addonizio 《Journal of the American Society of Echocardiography》2004,17(3):288-289
Diverticula arising from the mitral valve are very rare. They are usually detected by echocardiography as masses arising from the cardiac valves. We present a case of an incidental finding of a diverticulum arising from the mitral valve. This was initially detected by transesophageal echocardiography, and later confirmed by pathologic appearance. The case illustrates the unique findings on echocardiography that would help to differentiate diverticula from other valvular masses. 相似文献
57.
58.
Marcia C Willing James C Torner Trudy L Burns Kathleen F Janz Teresa A Marshall Julie Gilmore John J Warren Steven M Levy 《Journal of clinical densitometry》2005,8(1):39-47
Four hundred twenty-eight white children (200 boys and 228 girls) ages 4.5-6.5 yr had spine, hip, and whole-body bone mineral density (BMD) and bone mineral content (BMC) measured by dual-energy X-ray absorptiometry(DXA) as part of the Iowa Bone Development Study. Anthropometric measurements, including height, weight, and body mass index (BMI) were determined for each child at the time the bone measurements were made. The age- and gender-specific height percentile based on the 2000 CDC Growth Charts (www.cdc.gov/growthcharts/) was determined for each child. These percentiles were used to classify children into four groups as defined by the 25th, 50th,and 75th percentile cutpoints. Percentile distributions were determined within each height quartile group to delineate percentiles (5th, 25th, 50th, 75th, 95th) for BMD and BMC. Gender differences in BMD and BMC were investigated before and after stratification into height groups. Boys had higher age-height-weight-adjusted means for most BMD and BMC measures except spine BMD. Bone measurements increased with height quartile, indicating that taller children have greater BMD and BMC compared to shorter children of the same age and gender. Within any given quartile,mean BMD and BMC measurements were similar for boys and girls, with the exception of hip BMD, for which values were consistently higher for boys (p < 0.05). In addition, whole-body BMC values were higher for boys in quartiles 1 and 3 (p < 0.05). These bone measures provide norms for young white children and serve as a reference for comparison with other racial and ethnic groups, as well as with childhood populations that are at risk for osteopenia because of chronic disease. Gender, age, and height are useful clinical predictors of BMD and BMC in young children. 相似文献
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