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1.
G Dimitriou A Greenough B Laubscher N Yamaguchi 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1256-1260
Failure of patient-triggered ventilation in very immature infants may be due to the use of inappropriate triggering systems. Two types of airflow trigger were therefore compared consecutively to an airway pressure (SLE) triggering system. Each comparison was made in 10 infants, ≤28 weeks of gestation. Comparison was made of the delivered volume, trigger performance and blood gases using each system for 1 h. Both comparisons showed that the airflow triggering systems performed better: one (Draeger Babylog 8000) had a higher sensitivity ( p < 0:01) and the other (Bird VIP airflow trigger), in which inflation was terminated by sensing a reduction in inspiratory flow, had a lower degree of asynchrony ( p < 0:01) and a tendency to deliver higher volumes. These results suggest that triggering systems sensing airflow changes may be superior to those sensing airway pressure changes in very immature infants. The use of a mechanism to synchronize the termination of inflation to the end of the patient's inspiration may offer further advantages. 相似文献
2.
Vassilios A Lachanas Emmanuel P Prokopakis Panayotis N Christodoulou John K Hajiioannou Stylianos G Malandrakis Alexander D Karatzanis George A Velegrakis 《Otology & neurotology》2006,27(8):1162-1165
OBJECTIVE: To compare laser-assisted tympanostomy (LAT) with radiofrequency myringotomy (RFM), as well as the effectiveness of mitomycin C (MC) on the above techniques, in rabbits. STUDY DESIGN: Experimental animal research protocol. SETTING: University of Crete, School of Medicine, Medical Experimental Education and Research Center. METHODS: Bilateral myringotomies were performed under general anesthesia on 40 rabbits. LAT was performed on 20 animals (40 ears) and RFM on the remaining 20 animals (40 ears). MC (0.3 mg/mL) pledgets were applied to the right ears and saline pledgets to the left ears. Animals were monitored weekly using otomicroscopy until myringotomy closure. Kaplan-Meier survival techniques were used to compare myringotomy patency times. INTERVENTIONS: Under general anesthesia, bilateral LAT was performed on 20 rabbits and bilateral RFM on 20 rabbits. MAIN OUTCOME MEASURES: Myringotomy patency time. RESULTS: The mean patency times of the saline-treated ears were: 1.85 weeks (95% confidence interval [CI], 1.556-2.144 wk) for the LAT group and 1.70 weeks (95% CI, 1.494-1.906 wk) for the RFM group. This difference was not significant (p > 0.5). MC application significantly prolonged mean patency time (p < 0.0001) in both LAT and RFM groups. The mean patency times in the MC-treated ears were 5.45 weeks (95% CI, 5.226-5.674 wk) for the LAT group and 5.55 weeks (95% CI, 5.285-5.815 wk) for the RFM group. This difference was not significant (p > 0.5). CONCLUSION: There is no significant difference in myringotomy patency times between LAT and RFM techniques in rabbits, whereas MC significantly prolongs the patency rate of either technique. 相似文献
3.
Demetrios Antoniades John D Harrison Apostolos Epivatianos Panayotis Papanayotou 《Journal of oral and maxillofacial surgery》2004,62(4):431-434
PURPOSE: We sought to describe the treatment of chronic sialadenitis by intraductal penicillin or saline. PATIENTS AND METHODS: The study group consisted of 32 males and 23 females with chronic submandibular sialadenitis aged 12 to 65 years and 16 males and 11 females with chronic parotitis aged 8 to 65 years who were treated by intraductal instillation of penicillin or saline. RESULTS: In the patients with submandibular sialadenitis, 44 patients treated with penicillin and 11 treated with saline became symptom free; symptoms recurred in 3 treated with penicillin, of whom 2 became symptom free after further instillations and 1 after removal of a sialolith at the ductal orifice; and follow-up of 22 patients verified that 18 treated with penicillin and 4 with saline had been symptom free for 1 to 15 years and 1 to 3 years, respectively. In the patients with parotitis, 18 patients treated with penicillin, 8 treated with saline, and 1 treated with both became symptom free; symptoms recurred in 1 treated with penicillin and 1 with saline, both of whom became symptom free after further instillations; and follow-up of 15 patients verified that 11 treated with penicillin, 3 with saline, and 1 with both had been symptom free for 1 to 14 years, 2 to 12 years, and 3 years, respectively. CONCLUSION: The intraductal instillation of penicillin or saline is a simple and surprisingly successful technique for the treatment of chronic sialadenitis. 相似文献
4.
Theodore H. Xenakis Konstantinos N. Malizos Alexandros E. Beris Marios Vekris Anastasios D. Georgoulis Panayotis N. Soucacos 《Microsurgery》1994,15(7):479-484
Reconstruction of large bony defects of long bones was performed using vascularised fibular grafts in four patients at the Department of Orthopaedic Surgery of the University of Ioannina Medical School. Indications for grafting procedures in this small series had been the loss of bone due to the extensive resection of avascular and necrotic bone from septic pseudoarthrosis in three patients and congenital pseudarthrosis secondary to neurofibromatosis in a child. Primary skeletal union with graft hypertrophy occurred in three of the patients. The fourth patient had an asymptomatic nonunion at the proximal end of the graft. The result in each patient was the presence of a well-aligned limb that had normal or nearly normal motion and acceptable length. © 1994 Wiley-Liss, Inc. 相似文献
5.
Assessment of Resolution and Intercenter Reproducibility of Results of Genotyping Staphylococcus aureus by Pulsed-Field Gel Electrophoresis of SmaI Macrorestriction Fragments: a Multicenter Study 下载免费PDF全文
Alex van Belkum Willem van Leeuwen Mary Elizabeth Kaufmann Barry Cookson Fran?oise Forey Jerome Etienne Richard Goering Fred Tenover Christine Steward Frances O’Brien Warren Grubb Panayotis Tassios Nicholas Legakis Anne Morvan Névine El Solh Raf de Ryck Marc Struelens Saara Salmenlinna Jaana Vuopio-Varkila Mirjam Kooistra Adriaan Talens Wolfgang Witte Henri Verbrugh 《Journal of clinical microbiology》1998,36(6):1653-1659
Twenty well-characterized isolates of methicillin-resistant Staphylococcus aureus were used to study the optimal resolution and interlaboratory reproducibility of pulsed-field gel electrophoresis (PFGE) of DNA macrorestriction fragments. Five identical isolates (one PFGE type), 5 isolates that produced related PFGE subtypes, and 10 isolates with unique PFGE patterns were analyzed blindly in 12 different laboratories by in-house protocols. In several laboratories a standardized PFGE protocol with a commercial kit was applied successfully as well. Eight of the centers correctly identified the genetic homogeneity of the identical isolates by both the in-house and standard protocols. Four of 12 laboratories failed to produce interpretable data by the standardized protocol, due to technical problems (primarily plug preparation). With the five related isolates, five of eight participants identified the same subtype interrelationships with both in-house and standard protocols. However, two participants identified multiple strain types in this group or classified some of the isolates as unrelated isolates rather than as subtypes. The remaining laboratory failed to distinguish differences between some of the related isolates by utilizing both the in-house and standardized protocols. There were large differences in the relative genome lengths of the isolates as calculated on the basis of the gel pictures. By visual inspection, the numbers of restriction fragments and overall banding pattern similarity in the three groups of isolates showed interlaboratory concordance, but centralized computer analysis of data from four laboratories yielded percent similarity values of only 85% for the group of identical isolates. The differences between the data sets obtained with in-house and standardized protocols could be the experimental parameters which differed with respect to the brand of equipment used, imaging software, running time (20 to 48 h), and pulsing conditions. In conclusion, it appears that the standardization of PFGE depends on controlling a variety of experimental intricacies, as is the case with other bacterial typing procedures.The use of electric field pulsing techniques in conjunction with agarose gel electrophoresis for discrimination of large DNA molecules was introduced by Schwarz and Cantor in 1984 (9). During the past decade the methodology has been adapted and improved by various research groups to the point that pulsed-field gel electrophoresis (PFGE) for bacterial strain typing is now utilized with relative ease in a variety of laboratories (1). The combination of contour-clamped homogeneous field electrophoresis and PFGE for the molecular analysis of Staphylococcus aureus has been reported since the late 1980s (7, 19). At present, PFGE is considered to have both the reproducibility and resolving power of a standard technique for the epidemiological typing of bacterial isolates (10, 15).Molecular typing systems can identify different strains within a species, generating data useful for taxonomic or epidemiologic purposes (10, 14). A frequently observed shortcoming of typing systems in general is their lack of reproducibility: most typing systems do not provide a definitive strain identification, which is usually due to the variability of the technique and the lack of large databases containing fragment patterns from a wide variety of organisms to which unknowns can be compared. These problems were recently described in detail for two molecular typing systems. A multicenter study on random amplification of polymorphic DNA for discrimination of S. aureus strains revealed a lack of interlaboratory reproducibility among the banding patterns generated by the participating centers, although the epidemiological interpretation of the data was similar for all the centers involved (16). For PFGE, a similar lack of interlaboratory reproducibility of patterns was observed, although the interpretation of the experimental data also differed per participating center (2). The latter study analyzed 12 different methicillin-resistant S. aureus (MRSA) strains with different techniques optimized in each center and different sources and types of equipment. Since interlaboratory discrepancies with respect to classification of the strains were observed, the study concluded that there is a clear need for standardization of the technique, including the construction of a panel of reference strains to assist the individual researcher in the optimization of the PFGE protocol.The aim of the present study was to compare the fragment patterns of a well-defined collection of MRSA isolates in 12 laboratories using in-house and a standard set of PFGE parameters to determine whether standardization of experimental parameters (DNA preparation and switching protocols) would improve intercenter reproducibility of PFGE analysis. 相似文献
6.
We have previously identified five thyroglobulin (Tg) peptides with Ak-binding motifs that induce experimental autoimmune thyroiditis (EAT) in CBA/J (H-2k) mice. In this study, we have examined whether H-2 or non H-2 genes can influence the immunopathogenicity of peptide p2596 (a.a. 2596-2608), which earlier elicited considerable pathology in CBA/J hosts. The p2596 peptide induced mild EAT--(infiltration index range=1-2)-- in H-2-compatible AKR/J, B10.BR, and C3H/HeJ mice. Moreover, p2596-primed LNC from these mice exhibited peptide-specific proliferative responses and secreted significant amounts of IL-2 and IFN-gamma in recall in vitro assays. Priming and boosting of these strains with p2596 resulted in the generation of specific IgG responses five weeks after the initial challenge. In contrast, s.c. challenge of H-2-incompatible strains such as DBA/1J (H-2q), SJL (H-2s), DBA/2J (H-2d) and C57BL/6 (H-2b) with the same peptide dose did not elicit EAT pathology and peptide-specific B- or T-cell responses. These data demonstrate the thyroiditogenic potential of p2596 in H-2k strains of diverse non-H-2 backgrounds but not in mice carrying H-2b, d, q or s haplotypes. 相似文献
7.
Abu-Helu RF Dimitriou ID Kapsogeorgou EK Moutsopoulos HM Manoussakis MN 《Journal of autoimmunity》2001,17(2):141-153
Sjogren's syndrome (SS) is an exocrinopathy characterized by T cell infiltrates, salivary gland epithelial cell (SGEC) apoptosis and high Fas and FasL expression. To address the participation of T cell-derived cytokines and of Fas apoptotic pathway in SS glandular lesions, we utilized non-neoplastic SGEC lines established from SS patients and controls. Possibly attesting to their intrinsic activation, cell lines derived from SS patients displayed significantly higher constitutive Fas and FasL than controls. Surface co-expression of Fas and FasL was not associated with spontaneous fratricide apoptosis. SGEC were resistant to anti-Fas-mediated apoptosis (possibly owing to the constitutive expression of anti-apoptotic proteins cFLIP and Bcl-2), but became sensitive after protein or RNA synthesis inhibition. IFN-gamma and TNF-alpha were able to upregulate surface Fas and FasL, whereas IL-1beta downregulated surface FasL. IFN-gamma (but not several other cytokines) reduced the survival of SGEC in a dose- and time-dependent manner and induced Fas/FasL-mediated apoptosis, directly and via anoikia. Dexamethasone inhibited the upregulation of Fas and FasL by IFN-gamma and the induction of SGEC apoptosis and detachment by anti-Fas mAb or IFN-gamma. Our findings indicate the injurious role of IFN-gamma for the salivary epithelia of SS patients through the induction of Fas-mediated apoptosis and anoikia. 相似文献
8.
Patrinos GP Garinis G Kounelis S Kouri E Menounos P 《Journal of molecular medicine (Berlin, Germany)》1999,77(9):686-689
We report a novel p53 deletion in a 63-year-old female with breast cancer. Mutation screening of DNA samples, obtained from tumor specimens from 98 individuals with breast cancer, by a combined polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis showed that the index case had a somatic mutation identified to be a 23-bp deletion in exon 5 of the p53 gene. This deletion would be expected to yield a truncated and functionally inactive p53 protein molecule, probably resulting in cell transformation. The existence of 6-bp palindromic-like sequences encompassing the deleted fragment suggests that the slipped mispairing mechanism is not involved in producing the deletion, which probably resulted from palindromic pairing during replication. 相似文献
9.
Zafirakis P Markomichelakis NN Voudouri A Theodossiadis GP Theodossiadis PG 《Documenta ophthalmologica. Advances in ophthalmology》1999,97(3-4):311-315
Purpose: To describe a patient with acquired immunodeficiency syndrome (AIDS) who presented with cystoid macular edema (CME) which
was not associated with active cytomegalovirus (CMV) retinitis or AIDS-related microvasculopathy. Method: A 32-year-old man with AIDS and a past ocular history of inactive CMV retinitis was placed on protease inhibitors when his
CD4+ T lymphocyte counts dropped to 8 cells/mm3. Three months later, after his CD4+ T lymphocyte counts had increased to 196 cells/mm3 he complained of micropsia and metamorphopsia in his right eye of 1 week duration. The patient had a complete ocular examination
including fluorescein angiography (FA). Results: Visual acuity (VA) was 7/10 OD. Fundus examination revealed CME and inactive CMV retinitis, and FA demonstrated CME and a
hot disc. Two transseptal injections of corticosteroids were administered 2 weeks apart in the right eye as treatment of the
CME. The patient reported gradual visual improvement and 6 weeks later, his VA was 10/10-2. CME had resolved clinically and angiographically. Conclusions: CME in our case is associated with inactive CMV retinitis and gradually increasing number of CD4+ T lymphocytes after initiation of treatment with protease inhibitors. It may be amenable to regional administration of corticosteroids
without reactivation of retinitis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Nita L Seibel Sierra Li Norman E Breslow J Bruce Beckwith Daniel M Green Gerald M Haase Michael L Ritchey Patrick R M Thomas Paul E Grundy Jerry Z Finklestein Tae Kim Stephen J Shochat Panayotis P Kelalis Giulio J D'Angio 《Journal of clinical oncology》2004,22(3):468-473
PURPOSE: To evaluate the effect of conventional and standard (ST) versus pulse-intensive (PI) chemotherapy and short-duration versus long-duration chemotherapy on relapse-free survival (RFS) and overall survival rates of patients with clear-cell sarcoma of the kidney (CCSK) entered onto the National Wilms' Tumor Study (NWTS)-4. PATIENTS AND METHODS: The 5-year and 8-year RFS rates were determined for patients with CCSK treated on the NWTS-4. After August 6, 1986, 40 previously untreated children younger than 16 years with CCSK were randomly assigned, after the completion of 6 months of chemotherapy, to discontinue (short) or continue 9 additional months (long) of treatment with chemotherapy regimens that included vincristine and either divided-dose (ST) courses (5 days) or single-dose (PI) treatment with dactinomycin and divided-dose (ST) courses (3 days) or single-dose (PI) treatment with doxorubicin. RESULTS: For patients with CCSK, the 5- and 8-year RFS rates were 65.2% and 60.6%, respectively, for patients randomly assigned to the short chemotherapy and 87.8% (both 5- and 8-year RFS) for patients randomly assigned to the long chemotherapy (P =.08). The overall survival rates for patients at 5 and 8 years were 95.5% and 85.9%, respectively, for the short chemotherapy and 87.5% (both 5- and 8-year overall survival) for the long chemotherapy (P =.99). In NWTS-4, the overall survival rates for patients with CCSK improved from NWTS-3 (83% v 66.9% at 8 years, respectively; P <.01). CONCLUSION: CCSK patients exhibit an improved RFS from a longer course of therapy when using vincristine, doxorubicin, and dactinomycin, but their long-term survival is unchanged compared with patients receiving 6 months of therapy. The overall survival rates for patients with CCSK have improved from NWTS-3. 相似文献