In emphysema patients, gas dilutional alveolar volume is underestimated by a 10s single breath maneuver at total lung capacity (TLC) compared with re-breathing at functional residual capacity (FRC); corresponding underestimation of single breath diffusing capacity (DLCO) in emphysema has not been demonstrated. The purpose of this study was to quantify the degree to which re-breathe DLCO at FRC (DLCO(RB)) differs from single breath DLCO at TLC (DLCO(SB)) in emphysema. In 37 consecutively recruited patients with moderate to severe emphysema (FEV1/FVC 40%±10% predicted), DLCO(RB) as % predicted of 91 controls without cardiopulmonary disease was 79%±24%, significantly greater than % predicted DLCO(SB) (44%±19%; p<0.0001). DLCO(RB)/DLCO(SB) was inversely proportional to FEV1% predicted (R = -0.47, p=0.004), and FEV1/FVC (R = -0.54, p<0.001). These data indicate that a 10s single breath DLCO maneuver progressively under-represents re-breathe lung diffusing capacity in emphysema as airflow obstruction increases. 相似文献
A new multiparameter sensor that combines electrochemical and fibre-optic technology was used for continuous in-vivo investigation of pH, carbon dioxide partial pressure (PCO(2)), oxygen partial pressure (PO(2)), bicarbonate concentration (HCO(3)(-)), base excess, and oxygen saturation (O(2)Sat) early in human pregnancy. The sensor was inserted into the amniotic cavity and the placental bed of 16 pregnancies at 10-15 weeks gestation, before termination under general anaesthesia. Amniotic fluid and retroplacental blood from the same site were also aspirated and analysed by means of cartridges and a portable blood gas analyser. Eleven series of measurements were obtained. The variation in measurements over the 5 min of monitoring was =10% for all parameters. The sensor was damaged during insertion into the amniotic cavity in one case and in the placental bed in four cases. Measurements of PO(2) in both the amniotic cavity and the placental bed and of pH in the placental bed were higher using the cartridges than in vivo. The results indicated that in-vivo monitoring of fetoplacental gas and acid-base with a sensor is stable and accurate. Such technology will be helpful in improving our understanding of the fetoplacental metabolism in normal and complicated pregnancies. 相似文献
In medical devices, nonconformance with Digital Imaging and Communications in Medicine (DICOM) standard is a serious risk. DICOM nonconformance radiology devices could cause undetected image loss, increasing examination time, and costs in health centers and could even result in the wrong patient treatment. However, there is a rich literature on medical standards that identify the best practices for producing safe and effective medical software. However, these standards do not expressly provide tools to deal with all the relevant DICOM compatibility issues in a specific case. This study aims to introduce a systematic software development workflow that complies with medical standards and ensures DICOM conformance of a new or upgraded radiology software project. In this approach, DICOM conformance gets the highest priority, and the whole software project is organized around it. Software requirement analysis, risk evaluation, and test management tasks are arranged systematically to make the final device DICOM conformant. This conceptual framework was developed during the R&D work towards a novel radiography device, and it could be employed as a roadmap in other medical imaging software projects. The proposed methodology controls the DICOM compatibility risk of the final software, and its systematic evaluation complied with medical standards.
Contamination of propofol, in an emulsion formulation, has been associated with infective complications. Local anaesthetics,some of which are known to have antibacterial properties, are frequently added to the solution to reduce pain on injection. We examined the growth rates of E. coli, S. aureus, S. epidermidis and P. aeruginosa in propofol with and without lignocaine 0.1%-2% after incubation for 2, 5 and 24 hours at 37 degrees C. Growth of microorganisms in each solution was compared by counting the number of colony forming units (CFU). Propofol supported the growth of all microorganisms. An increase in the number of CFUs was observed in all drug combinations 2, 5 and 24 hours after inoculation except for S. aureus (P<0.05). No difference was found in CFU numbers between 2 and 5 hours for this microorganism. With E. coli, a significant decline in colony counts was observed in mixtures of 1% and 2% lignocaine (P<0.05). With the other microorganisms only 2% lignocaine showed a significant reduction in the number of CFUs (P<0.05). We conclude that lignocaine in recommended clinical doses (0.05%-0.1%) did not exhibit adequate antibacterial activity to prevent infective complications. 相似文献
The purpose of this study was to examine the effect of glass fibre reinforcement on the dimensional changes and water sorption of a heat-polymerising denture acrylic polymer and a microwave-polymerising denture acrylic polymer. Fifteen specimens from each group were prepared with 2% by weight (18 mg) E-glass fibre and 15 without glass fibre. The dimensional change measurements were made at three different stages on the 60 specimens. The water sorption calculations were made on specimens immersed in distilled water at 37 degrees C +/- 1 degree C for 0, 1 and 7 days. Glass fibre reinforcement and processing method do not affect the dimensional change of test specimens, but as the time increased the dimensional change decreased. The glass fibre reinforcement decreased water sorption, but the two processing methods failed to show a significant difference. 相似文献
BACKGROUND: Perthes Disease (PD) is generally a self-limiting disease of childhood but it causes severe pain and may lead to deformity of the femoral head. Intravascular thrombosis seems to form the main mechanism in the pathogenesis of the disease. The aim of this study was to determine hereditary thrombotic risk factors in Turkish children with PD. METHODS: In 46 Perthes patients (35 male, 11 female), family history of thrombotic events was investigated, Protein C (PC), free-Protein S (f-PS), antithrombin (AT) activities, fibrinogen level, and resistance to activated Protein C (APC) were measured. The results were compared with a healthy control group of 79 children matched by age and sex. The relationship between the severity of disease and coagulation system abnormalities was evaluated. RESULTS: While the mean PC and AT activities were significantly lower in the patients than those of the controls, the proportions of patients with low AT activity, resistance to APC, and a history of hereditary thrombophilia were significantly higher than those of the controls. No difference was observed in coagulation system disorders relative to severity of the disease and bilateral or unilateral disease involvement. CONCLUSIONS: This study shows that a possible association between PD and inherited hypercoagulability. Determination of thrombotic risk factors in these patients may bring a new approach to the treatment. Most importantly, this may be a stimulant to take precautions for other thrombotic events, which patients may face later in life. 相似文献
The role of tonsillectomy in the periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome, is controversial. Although some studies reported high success rates with tonsillectomy, further investigations are needed with larger numbers of patients.
Objective
To seek the long-term outcomes of tonsillectomy in periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome.
Methods
Case series; multi-center study. The study comprised 23 patients with periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome who underwent surgery (tonsillectomy with or without adenoidectomy) between January 2009 and November 2014.
Results
21 (91%) of 23 patients had complete resolution immediately after surgery. One patient had an attack 24 h after surgery, but has had no further attacks. One patient had three attacks with various intervals, and complete remission was observed after 3 months.
Conclusions
Tonsillectomy is a good option for the treatment of periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome. 相似文献
Objective: To investigate the effects of topical travoprost 0.004% and topical bimatoprost 0.03% on retrobulbar blood flow (RBF). Methods: Nineteen young healthy men without any known ocular or systemic disorder were enrolled in this prospective, double-masked, randomized, cross-over study. Baseline RBF mea- 相似文献