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21.
A model to examine the effects of proliferating Aspergillus fumigatus ATCC 26933 colonies embedded in a thin layer of soft agar on a monolayer of A549 cells was developed and enabled an investigation of the response of cultured cells to fungal growth. This model simulates the conditions on the respiratory surface in patients with invasive aspergillosis and also in the mucus secretions of cystic fibrosis patients with allergic bronchopulmonary aspergillosis. Conidia of A. fumigatus adhering to A549 cells were immobilized in a thin layer of soft agar (0.6% (w/v)) and allowed to germinate at 37 degrees C. Fungal colonies greater than 5 mm in diameter caused rounding-up and detachment of A549 cells underneath the colony and towards the hyphal tips. As the fungal colony diameter increased, cell detachment occurred ahead of the hyphal tips. Cells detached for short periods (less than 6 h) showed no annexin-V (AV) or propidium iodide (PI) staining, suggesting no externalization of phosphatidylserine and an intact plasma membrane. Cells that had detached for periods greater than 6 h were positive for AV and PI indicating the rupture of the plasma membrane and cell death by necrosis. Chemical extraction and separation by thin layer chromatography of agar from zones of cell detachment around fungal colonies revealed the presence of three compounds that may play a role in inducing cell death. 相似文献
22.
A case of benign mesenchymoma of the hard palate is presented. The lesion was completely excised and the tumor margins were shown to be free of disease. Within 4 months a second noncontiguous lesion arose of the opposite side of the palate and was also removed. Whether this represented a distinctly new lesion or possibly one which was seeded through previous diagnostic efforts was difficult to ascertain. Follow-up for more than 2 years has not revealed any further evidence of neoplasia. 相似文献
23.
24.
Cytomegalovirus Disease in High-Risk Transplant Recipients Despite Ganciclovir or Valganciclovir Prophylaxis 总被引:10,自引:0,他引:10
Enver Akalin Vinita Sehgal Scott Ames Sabera Hossain Lisa Daly Murphy Barbara Jonathan S. Bromberg 《American journal of transplantation》2003,3(6):731-735
The clinical patterns and predictors of cytomegalovirus (CMV) disease in kidney and/or pancreas transplant patients on ganciclovir (1.0 g po t.i.d.) or valganciclovir (450 mg po q.d.) prophylaxis were studied. This is a retrospective analysis of 129 transplant recipients. Median follow up was 12 months (range, 6-18 months). The overall incidence of CMV disease at 1-year post-transplant was 14% (4% tissue-invasive, 10% noninvasive). Seventeen of 18 patients were diagnosed with CMV after completion of 3 months' prophylaxis (median 8 weeks, range, 2-28 weeks). Induction treatment with thymoglobulin, and Donor +/Recipient - CMV status were the strongest predictors for the development of CMV disease. Cytomegalovirus incidence was not different between patients treated with ganciclovir or valganciclovir (15 vs. 17%, respectively). Valganciclovir (450 mg q.d.) is as effective as oral ganciclovir in CMV prophylaxis. High-risk individuals might require higher doses or longer duration of valganciclovir treatment. 相似文献
25.
P Daly 《The British journal of theatre nursing》1992,2(2):8-9
Perfusionists are highly skilled professionals providing essential life support, enabling patients to undergo open heart surgery. Although this is the main function at the Royal Liverpool Children's Hospital, Alder Hey, they also manage a Homograft bank. Also known as a heart valve bank, this is a completely independent branch of the perfusion department. 相似文献
26.
This paper presents a review of the extracranial evaluation and treatment of cerebrospinal fluid (CSF) rhinorrhea. Diagnosis with attention to a careful history and physical with maneuvers which exacerbate drainage and thorough physical exam along with imaging techniques are discussed. The common etiologies of CSF rhinorrhea including trauma, spontaneous leakage, tumor, and iatrogenic injury are included. Management consists of conservative measures including the avoidance of straining maneuvers which increases intracranial pressure. Periodic drainage of CSF via lumbar puncture or continuous drainage via flow-regulated systems may also be of benefit in attempts of conservative management. Failure of conservative management, constant leakage, pneumocephalus, and recurrent meningitis are indicators for surgical repairs. Ethmoid-cribiform plate region repairs are generally approached by external ethmoidectomy and the development of mucoperiosteal flaps from various donor sites which are then rotated to the leak area to seal the defect. Frontal sinus leaks are usually repaired via an osteoplastic flap technique with direct repair of the dural defect or the use of fascial graft tucked under the bony defect, then obliterated with abdominal fat. CSF rhinorrhea presents a diagnostic and surgical challenge to the otolaryngologist. After diagnosis and localization, operative repair using extracranial approaches is accepted as the initial method of intervention in these cases. 相似文献
27.
Background: There are few detailed nutritional studies analysing dietary intakes and weaning practices of inner city infants aged 0–12 months. Pasteurized cow's milk (PCM) is not recommended as a main drink until after 1 year of age, although early usage is still common. Premature introduction of pasteurized cow's milk is associated with increased risk of iron deficiency anaemia. Methods: We therefore prospectively examined the dietary effect of early introduction of pasteurized cow's milk on the nutritional intake of 100 infants (mean age at recruitment 7.8 months), whose mothers had already elected to introduce cow's milk before the recommended age of 12 months in a deprived inner city area. In addition, a retrospective questionnaire on feeding practices and food choices was administered and information on parental education and employment was collected, together with a 3-day dietary diary of weighed intakes at recruitment. Results: The results indicate that weaning practices are handed down from family and friends and are intuitive rather than informed. Over 80% of the infants had intakes of iron, zinc and vitamin D below the reference nutrient intake (RNI) and a further 41% had low vitamin C intakes. Prior to introduction of PCM, there was also misuse of infant formula. Twenty per cent added an extra scoop of powder to the feeds, 10% added milk powder to the bottle before addition of water and 30% used microwave ovens to heat the infant bottle. Conclusion: Feeding practices in a deprived inner city area differed substantially from guidelines and infants were at risk of developing nutrient deficiencies as well as poor feeding practices. 相似文献
28.
K S Rao J E Warnick J W Daly E X Albuquerque 《The Journal of pharmacology and experimental therapeutics》1987,243(2):775-783
The mechanism of the twitch potentiating action of pumiliotoxin-B (PTX-B), an indolizidine alkaloid from the skin of the frog Dendrobates pumilio, was studied on frog skeletal muscles. In the presence of PTX-B, a single stimulus to the muscle produced either a burst of repetitive action potentials superimposed on a depolarizing afterpotential or a single potential with a prolonged afterpotential at junctional as well as extrajunctional regions of the frog skeletal muscle fibers. The alkaloid did not cause repetitive activity in quiescent cells or spontaneous contractions. The duration of the burst of action potentials was related inversely and the amplitude and duration of postburst depolarizing after-potential was related directly to the concentration of PTX-B. The typical pattern of repetitive action potentials and postburst depolarization induced by PTX-B could be mimicked by depolarizing the muscle membrane with current pulses of long duration (150-470 ms). Lowering the external calcium or sodium concentration reduced the ability of PTX-B to initiate repetitive action potentials, whereas a low external chloride concentration had no effect. The frequency of MEPPs evoked by potassium, but not the spontaneous MEPP frequency, was increased by PTX-B, suggesting a selective effect on evoked transmitter release. PTX-B evoked repetitive EPPs in response to a single stimulus applied to the nerve, which was dependent upon the external calcium ion concentration. The amplitudes of EPPs in the train were facilitated, and their amplitude increased linearly at the lowest calcium concentration, but not at concentrations from 0.45 to 1.8 mM.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
29.
John F. Teare Roger W. Peterson Karen Authier Linda Schroeder Daniel L. Daly 《Child & youth care forum》1998,27(2):125-138
The purpose of this study was to examine the correlates of post-shelter maternal family satisfaction in a group of youth who
were reunified with their families following a shelter stay. Findings indicated that higher ratings of family satisfaction
were related to greater maternal problem solving skill and less family conflict. 相似文献
30.
Wagner Costalas J Itzen M Malick J Babb JS Bove B Godwin AK Daly MB 《American journal of medical genetics. Part C, Seminars in medical genetics》2003,(1):11-18
We describe results from a survey designed to assess patterns of communication within families shortly after an individual receives results of BRCA1 and BRCA2 mutation carrier status. Shortly after disclosure of BRCA1 and BRCA2 genetic test results, the proband was contacted by phone to administer the post disclosure survey. Questions asked included whether they had shared their results with their siblings or adult children, if there were difficulties in communicating the test results, and if there was any distress associated with the sharing of results. A total of 162 women who have received results from BRCA1 and BRCA2 genetic testing participated in the survey. The probands shared their results more often with their female than their male relatives (P < 0.001). Probands who had tested positive for a mutation in the BRCA1 or BRCA2 gene shared their results more often with their relatives than did probands who were not carriers (P = 0.002). Probands reported more often that their siblings rather than their adult children had difficulties understanding the results (P = 0.001). The probands who were carriers more often reported having difficulties explaining their results to their relatives (P < 0.001) and their relatives were upset on hearing the result more often than were the relatives of probands who were not carriers (P < 0.001). The probands who were carriers reported more often that they were upset explaining their results to their relatives than did the probands who were not carriers (P < 0.001). Individuals are disclosing their test results to their relatives. Probands who are BRCA1- or BRCA2-positive are more likely to experience difficulty and distress with the communication of their test results to family members. 相似文献