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21.
F D Martinez 《Pediatrics》1991,87(2):190-198
Respiratory failure is almost certainly the cause of death in the majority of cases of sudden infant death syndrome (SIDS), but the mechanisms leading to it have not been elucidated. SIDS shares many environmental and socioeconomic risk factors with severe forms of bronchiolitis, and the age distribution of incident cases is similar. Present knowledge of lung and airway development during infancy, determinants of peripheral airway patency, changes in lung surface activity in infants with SIDS, and fluid film dynamics in small airways are reviewed. It is hypothesized that many cases of SIDS may be due to a final episode of progressive peripheral bronchial occlusion in infants with preceding critically diminished conductance of the smaller airways. 相似文献
22.
Dominick Sabatino Santiago Martinez Rosemarie Young Howard Balbi Peter Ciminera Marianne Frieri 《Pediatric hematology and oncology》1991,8(4):355-359
The case of a 7-year-old girl with acquired immunodeficiency syndrome treated for 5 years with AZT and intravenous gamma globulin is reported. Shortly before her demise she developed a pulmonary leiomyosarcoma and leiomyoma. Does prolonged survival in pediatric acquired immune deficiency syndrome increase the incidence of secondary malignancies? 相似文献
23.
Laurie M. Lomasney John F. Madden Wagdy S. Rizk Lawrence W. Hedlund Salutorio Martinez Robert E. Coleman William J. Richardson H. Dirk Sostman 《Journal of magnetic resonance imaging : JMRI》1994,4(3):441-449
Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise. 相似文献
24.
J J Pessey G Fourtanier J P Chavoin G A Moreau E Serrano L M Martinez 《Archives of oto-rhino-laryngology》1989,246(5):384-387
The authors report their surgical experiences with 55 extensive tumours of the pharyngoesophageal junction. Thirty-three of these cases were managed by circular pharyngolaryngectomy, total oesophagectomy with stripping and left coloplasty, and 22 were treated with circular pharyngolaryngectomy with free intestinal transplants. A comparative study of the post-operative courses of the patients and their oncological and functional outcomes shows the advantages, disadvantages and indications of these two techniques. 相似文献
25.
26.
This paper describes a new approach to the neurolytic block of the celiac plexus through the anterior abdominal wall using CT guidance. In 5 patients, CT guidance was used for needle placement and visualization of the spread of the injection. Once the pain has been relieved on completion of the neurolytic block, the radiologist proceeds with the biopsy. Pain relief was obtained in 80% of the cases after 2 weeks and in 60% after 6 months. No serious complications were observed. The anterior approach is simple and is useful in those patients with upper chronic abdominal pain scheduled for biopsy of the pancreas, and in those terminally ill patients who cannot tolerate the prone position. 相似文献
27.
Cephalosporin C acylase in the autolysis of filamentous fungi 总被引:2,自引:0,他引:2
F Reyes M J Martinez C Alfonso J L Copa-Patino J Soliveri 《The Journal of pharmacy and pharmacology》1990,42(2):128-131
Cephalosporin C acylase activity was studied using fluorescamine determination of free--NH2 groups produced in the deacylation of cephalosporin C by the enzyme. Fourteen fungi from different genera were studied and low extracellular cephalosporin C acylase activity was found in the genera Aspergillus, Fusarium and Penicillium. Forty one fungi of these genera were checked but not all presented acylase activity. The enzyme was generally found to be an extracellular enzyme and during the process of autolysis its activity increased with incubation time and with increasing pH of the medium. In no case was beta-lactamase activity detected. Penicillium rugulosum and Penicillium griseofulvum were identified as good cephalosporin C acylase producers. Deacetyl esterase activity was also detected in these fungi. 相似文献
28.
A colony of Toxorhynchites moctezuma was established at the Caribbean Epidemiology Centre in Trinidad in 1984. Toxorhynchites moctezuma was maintained in cages with high humidities. Eggs were deposited most frequently in a cut bicycle tire containing water. A minimum of 42 h was required for hatching, but 94% hatched between 43 and 51 h. Aedes aegypti larvae were supplied as prey. Larval development times varied with the quantity of prey offered, but when fed ad lib, peak developmental time was 18 days. Mean pupal developmental time was 5.5 days. Although only 12% of larvae survived to pupation in 3 years of production, our experience indicates this species would be a likely candidate for mass production and release. 相似文献
29.
We considered if the cyanosis frequently observed during a cough attack in patients with chronic lung disease was due to worsening hypoxemia. To investigate the effects of cough on PaO2, we measured arterial blood gases before and after a voluntary coughing period of 45 sec, in 11 patients with Interstitial Lung Disease (ILD) and 14 patients with Chronic Obstructive Lung Disease (COPD). All patients significantly increased (p less than 0.05) their PaO2 (COPD: from 49 +/- 2 to 60 +/- 2 mmHg; ILD from 44 +/- 2 to 51 +/- 3 mmHg, mean +/- SD) and decreased their PaCO2. We conclude that stable patients with COPD and ILD increase their PaO2 with coughing most likely due to hyperventilation. The cyanosis observed could be due to peripheral circulatory effects of coughing. 相似文献
30.
Carlos E Rodriguez Martinez Maria C Guzman Juan M Castillo Monica P Sossa Paulina Ojeda 《Pediatric critical care medicine》2006,7(4):335-339
OBJECTIVE: The primary goal of this study was to evaluate the validity of the North American-European Consensus Committee (NAECC) definition for acute respiratory distress syndrome (ARDS) in pediatric patients. A secondary aim was to evaluate the threshold value for the PaO2/FiO2 ratio, used to determine which pediatric patients have ARDS. DESIGN: Retrospective cohort study. SETTING: Pediatric intensive care unit. PATIENTS: Pediatric intensive care unit patients who required mechanical ventilation, died, and underwent autopsy between January 1, 1996, and December 31, 2002 (n = 34). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical and chest radiograph information was collected retrospectively through chart review using a standardized data collection tool. Data included the criteria specified in the NAECC definition of ARDS and demographic information. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of clinical diagnosis of ARDS compared with a pathologic diagnosis. The threshold value of PaO2/FiO2 was identified by plotting receiver operating characteristics curves and comparing the areas under the curves. The NAECC definition yielded a sensitivity of 80.7% (95% confidence interval 60-92%), specificity of 71.4% (95% confidence interval 30-95), positive predictive value of 91.3% (95% confidence interval 70-98), negative predictive value of 50.0% (95% confidence interval 20-78), and likelihood ratio of 2.82. A PaO2/FiO2 <150 had a slightly higher (but not significantly different) specificity for ARDS than a value >200 (71% vs. 86%, p = .15) without changing sensitivity. CONCLUSIONS: Our study suggests the need for further research with larger number of children to identify an optimal Pao2/Fio2 threshold for identifying ARDS in this population. 相似文献