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11.
Nishard Abdeen Albert Cross Gregory Cron Steven White Thomas Rand David Miller Giles Santyr 《Magnetic resonance in medicine》2006,56(2):255-264
We used the dual capability of hyperpolarized 129Xe for spectroscopy and imaging to develop new measures of xenon diffusing capacity in the rat lung that (analogously to the diffusing capacity of carbon monoxide or DLCO) are calculated as a product of total lung volume and gas transfer rate constants divided by the pressure gradient. Under conditions of known constant pressure breath-hold, the volume is measured by hyperpolarized 129Xe MRI, and the transfer rate is measured by dynamic spectroscopy. The new quantities (xenon diffusing capacity in lung parenchyma (DLXeLP)), xenon diffusing capacity in RBCs (DLXeRBC), and total lung xenon diffusing capacity (DLXe)) were measured in six normal rats and six rats with lung inflammation induced by instillation of fungal spores of Stachybotrys chartarum. DLXeLP, DLXeRBC, and DLXe were 56 +/- 10 ml/min/mmHg, 64 +/- 35 ml/min/mmHg, and 29 +/- 9 ml/min/mmHg, respectively, for normal rats, and 27 +/- 9 ml/min/mmHg, 42 +/- 27 ml/min/mmHg, and 16 +/- 7 ml/min/mmHg, respectively, for diseased rats. Lung volumes and gas transfer times for LP (TtrLP) were 16 +/- 2 ml and 22 +/- 3 ms, respectively, for normal rats and 12 +/- 2 ml and 35 +/- 8 ms, respectively, for diseased rats. Xenon diffusing capacities may be useful for measuring changes in gas exchange associated with inflammation and other lung diseases. 相似文献
12.
The purpose of this study was to investigate radiographic measurements in a cohort of patients with juvenile hallux valgus (with a hallux valgus angle > 15 degrees ) using standardized weightbearing x-rays compared with an age-matched control group. First metatarsal protrusion distance, metatarsus primus adductus angle, metatarsus adductus, first metatarsal cuneiform angle, calcaneal inclination angle, and talocalcaneal angles were assessed with discriminant functional analysis. A total of 37 sets of data were analyzed from patients with a mean age of 13.45 +/- 1.75 years. The study identified 2 significant components of juvenile hallux valgus: a positive first metatarsal protrusion distance (P <.001) and metatarsal primus adductus angle (P = .002). Discriminant functional analysis was then used to determine the best predictors of juvenile hallux valgus. This analysis allowed only 1 variable, metatarsal protrusion distance, as a predictor of whether juvenile hallux valgus was present (P < .001), with 94.3% accuracy. This study showed that a positive metatarsal protrusion distance is a significant component of juvenile hallux valgus. 相似文献
13.
Theodore C. Bania MD MS Tom Ashar MD Gregory Press MD Patricia M. Carey MD 《Academic emergency medicine》2003,10(7):697-704
Long-term daily use of gamma-hydroxybutyrate (GHB) and related compounds has recently been associated with a withdrawal syndrome. To the best of the authors' knowledge, there are currently no animal models of GHB withdrawal. OBJECTIVES: The authors studied and described the effect of chronic dosing of GHB (3-6 days) on tolerance and withdrawal in a rat model. METHODS: Rats were administered GHB every three hours via intraperitoneal catheter. Groups of rats (2 per group) were dosed with GHB for either 3 (24 doses), 4 (32 doses), 5 (40 doses), or 6 (48 doses) days. The GHB dose was 0.25 g/kg for doses 1-8, 0.75 g/kg for doses 9-12, 1 g/kg for doses 13-16, 1.25 g/kg for doses 17-24, 1.5 g/kg for doses 25-32, 1.75 g/kg for doses 33-40, and 2 g/kg for doses 41-48. Following the last dose of GHB, the rats were scored using a 16-point ethanol intoxication-withdrawal scale rating spontaneous behaviors, response to handling, grooming, and neurological signs. Lower scores indicate intoxication, while higher scores indicate withdrawal. Scores were recorded at hours 0, 1, 2, 3, 4, 5, 6, 9, 12, and 24. RESULTS: Tolerance: Rats dosed with GHB for more days were less intoxicated one hour after their last GHB dose despite receiving higher doses. WITHDRAWAL: The scores for all rats dosed with GHB increased at hours 4 (p = 0.028), 5 (p = 0.037), 6 (p = 0.007), and 9 (p = 0.024) after the last dose, indicating withdrawal. The scores demonstrated a linear increase dependent upon the number of days of GHB dosing at hours 3 (p < 0.000), 4 (p = 0.004), 5 (p = 0.002), and 12 (p = 0.039) as well as prior to the last dose at hour 0 (p = 0.000). No rats developed seizures. CONCLUSIONS: Tolerance and mild withdrawal in rats can be induced by administering intraperitoneal GHB every three hours for 3-6 days. More prolonged dosing and higher doses of GHB may be necessary to induce severe withdrawal. 相似文献
14.
Gregory Guldner MD MS Jason Schultz BS Perry Sexton MD Corwyn Fortner BS Mark Richmond MD 《Academic emergency medicine》2003,10(2):134-139
OBJECTIVES: Physicians commonly use etomidate for adult rapid-sequence intubation (RSI), but the manufacturer does not recommend its use for children under 10 years of age due to a lack of data. The authors present their experience with etomidate for pediatric RSI in order to further develop its risk-benefit profile in this age group. METHODS: Trained abstractors reviewed the medical records for all children under 10 years old who received etomidate for RSI between July 1996 and April 2001. RESULTS: 105 children, with an average age of 3 (+/-2.9) years, received a median dose of 0.32 (+/-0.12) mg/kg of etomidate. The systolic blood pressure increased an average of 4 mm Hg (95% CI = -3.3 to 9.2); the diastolic blood pressure increased 7 mm Hg (95% CI = -3.1 to 11) within 10 minutes of receiving etomidate. The heart rate increased an average of 10 beats/min (95% CI = 4.0 to 17.4). Complications included three patients who vomited within 10 minutes of etomidate administration. There were no cases of documented myoclonus, status epilepticus, or new-onset seizures. Thirty-eight patients received corticosteroids during the hospital course, none for suspected adrenal insufficiency. Three patients died, all from severe brain injury. CONCLUSIONS: In children less than 10 years old, etomidate seems to produce minimal hemodynamic changes, and appears to have a low risk of clinically important adrenal insufficiency, myoclonus, and status epilepticus. The association between etomidate and emesis (observed in less than 3% of enrolled patients) remains unclear. For clinical situations in which minimal blood pressure changes during RSI are critical, etomidate appears to have a favorable risk-benefit profile for children under 10 years old. 相似文献
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17.
G F Watts L Gregory R Naoumova C Kubal K M Shaw 《European journal of clinical nutrition》1988,42(8):697-702
The onset of diabetic nephropathy is characterized by subclinical elevation of urinary albumin excretion, so-called 'microalbuminuria' (M). Dietary assessments were carried out in 15 insulin-dependent diabetic patients with persistent M and an equal number with persistently normal albumin excretion. The groups were matched for sex, age, duration of diabetes, body mass index, insulin dose and glycosylated haemoglobin; there were no significant differences in systemic blood pressure, glomerular filtration rate, blood glucose and serum albumin concentrations between the groups; retinopathy was significantly more frequent in patients with M. Diabetics with persistent M were found to consume a significantly larger amount of fat (expressed as grams and percentage of total energy) and a significantly smaller percentage of total energy as carbohydrate than patients with normal albumin excretion; total dietary energy was larger in those with persistent M, but the difference was not significant. No significant differences were found in protein and fibre intakes between the groups. Our findings suggest that an excess in the dietary consumption of fat relative to carbohydrate might play an important role in the pathogenesis of early nephropathy in insulin-dependent diabetes mellitus. We emphasize the importance of careful attention to nutrient intake in the prevention and treatment of diabetic complications. 相似文献
18.
19.
Patients with Fabry disease on dialysis in the United States. 总被引:9,自引:0,他引:9
Ravi Thadhani Myles Wolf Michael L West Marcello Tonelli Robin Ruthazer Gregory M Pastores Gregorio T Obrador 《Kidney international》2002,61(1):249-255
BACKGROUND.: Fabry disease results from an X-linked deficiency of lysosomal alpha-galactosidase A and is a rare cause of end-stage renal disease. Little is known about the characteristics of patients with Fabry disease that initiate dialysis in the United States, although data from Europe suggests these individuals have a poor survival. METHODS.: Using the United States Renal Disease System database, we first studied in detail 42 Fabry patients who initiated dialysis between April 1995 (following the introduction of the new detailed HCFA 2728 form) and July 1998. To examine crude survival in a larger cohort, 95 Fabry patients were studied who initiated dialysis between 1985 and 1993, similar to the European Registry. Diabetic and non-diabetic controls matched by age, gender, race, year of dialysis initiation, and initial dialysis modality were examined for comparison. RESULTS.: During the years 1995 to 1998, the mean age of Fabry patients that initiated dialysis was 42 years, 83% were Caucasian, and 10% were African American. Despite the X-linked inheritance of Fabry disease, 12% of Fabry patients on dialysis were female. At initiation of dialysis mean serum albumin and creatinine were significantly higher and mean body mass index was significantly lower among Fabry patients, but mean glomerular filtration rate was similar to controls. Fabry patients tended to have a lower three-year survival compared to non-diabetic controls, but the results were not significantly different. In a larger cohort of Fabry patients who initiated dialysis between 1985 and 1993, the three-year survival of Fabry patients was significantly lower than non-diabetic controls: 63% (95% CI, 50 to 75%) versus 74% (95% CI, 67 to 80%; P=0.03). CONCLUSION.: End-stage renal disease is associated with significant morbidity and mortality among patients with Fabry disease. Recent evidence that progression of Fabry disease may be attenuated by enzyme replacement therapy necessitates increased awareness of Fabry disease and its comorbidities. 相似文献
20.
Comparison of ThinPrep versus conventional smear cytopreparatory techniques for fine-needle aspiration specimens of head and neck masses. 总被引:2,自引:0,他引:2
Lloyd Ford Barry M Rasgon Raymond L Hilsinger Raul M Cruz Karen Axelsson Gregory J Rumore Thomas M Schmidtknecht Balaram Puligandla John Sawicki William Pshea 《Otolaryngology--head and neck surgery》2002,126(5):554-561
OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe. 相似文献