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21.
In four patients, a man aged 53, a woman aged 63 and two men aged 67 and 53 years, respectively, inspection of the hand led to the final diagnosis. In the first patient who presented with clubbing of the fingers and pulmonary hypertension, a small atrial septal defect was detected. The second patient had thick curved yellow nails and recurrent pleural effusions as part of this yellow nail syndrome. The third patient presented with clubbing and hypertrophic osteoarthropathy, a secondary complaint to adenocarcinoma of the lung. The fourth patient had increasing pulmonary hypertension as a secondary complaint to recurrent multiple pulmonary embolism from deep venous malformations of his right hand, arm and shoulder as a part of the Klippel-Trenaunay syndrome. These cases show that inspection of the hand may give a clue to the diagnosis.  相似文献   
22.
Carbohydrates are the most important source of food-derived energy. The metabolic effects of different types of carbohydrate can vary considerably, partially due to differences in glucose and insulin response. Several studies indicate that postprandial hyperglycaemia is associated with an increased risk of cardiovascular disease in patients with diabetes mellitus. For these patients, and possibly also for individuals with impaired glucose tolerance as well as for the healthy population at large, it may be of benefit to prevent postprandial hyperglycaemia. In order to manipulate the postprandial glycaemic response, an understanding of the underlying mechanisms of this response is crucial. The postprandial blood glucose level is influenced by a number of factors, such as the amount and type of ingested carbohydrates, gastric emptying rate and digestion and secretion of gastrointestinal and other hormones. Different approaches can be chosen to prevent postprandial hyperglycaemia, including changes in the diet and the use of drugs that delay gastric emptying or digestion of carbohydrates. The administration of gastrointestinal hormones or manipulation of the secretion of these hormones, are also possibilities. Investigating the regulation of the postprandial blood-glucose concentration and its possible manipulation could result in new approaches to preventing postprandial hyperglycaemia.  相似文献   
23.
OBJECTIVE: To assess the diagnostic value of Doppler sonography of the uterine arteries (DSUA) at 20-23 gestational weeks as screening procedure in a low risk population. PATIENTS AND METHODS: The study group consisted of 7508 singleton low-risk pregnancies. Doppler sonography of both uterine arteries was performed as routine part of anomaly scan. Impedance of both uterine arteries was registered using the mean PI of the two uterine arteries. In case of notch, "Notch-Index" was defined as (C-D)/C with D = post-systolic nadir and C = following zenith of the waveform. Outcome variables were placental abruption, pre-eclampsia, intrauterine growth retardation, intrauterine/neonatal death and preterm delivery before 32 completed gestational weeks. To discriminate normal and pathological waveform, incidence of adverse pregnancy outcome was related to four different definitions of pathological waveform. To describe the severity of impairment of perfusion, the frequency of adverse pregnancy outcome was related to different classes of impedance. RESULTS: To find a simple discrimination between normal and pathological uterine perfusion, best diagnostic performance was reached by a definition using a combination of high impedance and notch (no notch and mean PI > P'95 or unilateral notch and mean PI > P'90 or bilateral notch and mean PI > P'50). The prevalence of notch in nulliparae (8.5%) was higher than in parae (4.7%) and decreased with increasing gestational age (20 weeks: 8.6%-23 weeks: 5.4%). We found a clear relation between elevation of impedance, depth of notch and frequency of adverse pregnancy outcome with a frequency of complications varying from 3.2% (mean PI < or = 0.8, mean NI = 0.1) to 38.4% (mean PI > 2.0, mean NI > 0.1). CONCLUSION: Doppler sonography of the uterine arteries at 20-23 weeks has the capacity to predict at least a part of severe forms of adverse pregnancy outcome and to assess the probability of complications by quantification of the impairment of the uterine blood flow.  相似文献   
24.
Purpose: CO2 angiography is considered dangerous in the aortic arch where bubbles may cause critical cerebral and cardiac ischemia. We investigated CO2 distribution, physiologic effects in the heart, methods of detection and treatments. Methods: Eight pigs had CO2 and iodinated contrast arch angiograms in supine and both lateral decubitus positions. An electrocardiogram, physiologic data and cardiac ultrasound were obtained. Therapies included precordial thumps and rolls to lateral decubitus positions. Results: Supine high descending aorta CO2 injections floated retrograde up the arch during diastole and preferentially filled the right coronary artery (RCA): mean score 3.5 (of 4), innominate artery 2.4, left coronary artery 1.2; n = 17; p = 0.0001. Aortic root injections preferentially filled the RCA when the animal was supine, left coronary in the right decubitus position, and showed a diffuse pattern in the left decubitus position. Right decubitus rolls filled both coronaries causing several lethal arrhythmias. Precordial thumps successfully cleared CO2. Ultrasound is a sensitive detector of myocardial CO2. Conclusion: Arch distribution of CO2 primarily involves the RCA. Diagnostic ultrasound detects cardiac CO2 well. Precordial thumps are an effective treatment.  相似文献   
25.
A possible clinical application of electrical impedance tomography (EIT) might be to monitor changes in the pulmonary circulation, provided the reproducibility of the EIT measurement is adequate. The purpose of this study was threefold: the intra- and inter-investigator variability of repeated measurements was investigated. Three different regions of interest (ROI) were analysed to assess the optimal ROI. Twenty-four healthy subjects and six patients were included. The Sheffield applied potential tomograph (DAS-01P, IBEES, Sheffield, UK) was used. Electrodes were attached by investigator A, and duplicate EIT measurements were performed. After detachment and 45 min of rest, the protocol was repeated by another investigator B, and afterwards by the initial investigator A. Three ROIs were analysed: whole circle, 'inner half circle' and contour. The mean difference in impedance changes between observers is presented in arbitrary units (AU) +/- SD. Finally, the influence of age, body composition and sex on the EIT result was examined. For the contour ROI, the mean difference for the intra-investigator situation was -1.44 x 10(-2) +/- 18.45 x 10(-2) AU (-0.7 +/- 9.0%), and was 5.46 x 10(-2) +/- 21.66 x 10(-2) AU (2.7 +/- 10.8%) for the inter-investigator situation. The coefficient of reproducibility of the intra- and inter-investigator reproducibility varied between 0.89 and 0.97 for all ROIs (P < 0.0001). There is a relation between impedance change and age (correlation coefficient r = -0.63, P < 0.01 for contour ROI), and between impedance change and body mass index (BMI) (r = -0.53, P < 0.05). We found a significant difference in mean impedance change between groups of males and females. In conclusion, EIT results are highly reproducible when performed by the same investigator as well as by two different investigators.  相似文献   
26.
STUDY OBJECTIVES: To establish the value of electrical impedance tomography (EIT) in assessing pulmonary edema in noncardiogenic acute respiratory failure (ARF), as compared to the thermal dye double indicator dilution technique (TDD). DESIGN: Prospective clinical study. SETTING: ICU of a general hospital. PATIENTS: Fourteen ARF patients. INTERVENTIONS: In order to use the TDD to determine the amount of extravascular lung water (EVLW), a fiberoptic catheter was placed in the femoral artery. Measurements and main results: Fourteen consecutive ARF patients receiving mechanical ventilation were measured by EIT and TDD. EIT visualizes the impedance changes caused by the ventilation in two-dimensional image planes. An impedance ratio (IR) of the ventilation-induced impedance changes of a posterior and an anterior part of the lungs was used to indicate the amount of EVLW. For the 29 measurements in 14 patients, a significant correlation between EIT and TDD (r = 0. 85; p < 0.001) was found. The EIT reproducibility was good. The diagnostic value of the method was tested by receiver operator characteristic analysis, with 10 mL/kg of EVLW considered as the upper limit of normal. At a cutoff level of the IR of 0.64, the IR had a sensitivity of 93%, a specificity of 87%, and a positive predictive value of 87% for a supranormal amount of EVLW. Follow-up measurements were performed in 11 patients. A significant correlation was found between the changes in EVLW measured with EIT and TDD (r = 0.85; p < 0.005). CONCLUSION: We conclude that EIT is a noninvasive technique for reasonably estimating the amount of EVLW in noncardiogenic ARF.  相似文献   
27.
Automatic capture detection systems are currently available in several cardiac pacing devices. All current systems use low-polarization electrodes and no beat to beat detection system is available for all types of electrodes. In addition the success ratio for currently available systems is not always 100%. Failure to detect capture reliably is often related to the behaviour of the electrode-tissue interface under different circumstances. Pacemaker electrodes can be considered electrochemical cells with complicated characteristics depending on time, temperature and electrical charge. This electrochemical cell is disturbed when a charge is transferred across the electrode-tissue interface during pacing. Several measures can be taken in order to minimise this disturbance or pace polarization artefact (PPA) including the use of high active surface area electrodes and application of tri-phasic pacing pulses. Another factor influencing detection of evoked potentials is the input circuit of the pacemaker affecting the PPA and the evoked response. Positive PPAs can be falsely interpreted as evoked potentials due to the undershoot of the second order filters applied in modern cardiac pacemakers. This paper explains the behaviour of the interface between the electrode and the cardiac tissue in combination with the pacemaker output circuits and input amplifiers under different circumstances.  相似文献   
28.
Hodgkin and Reed-Sternberg (HRS) cells in Hodgkin lymphoma (HL) secrete factors that interact with inflammatory background cells and may serve as biomarkers for disease activity. To detect new proteins related to pathogenesis, we analyzed the secretome of HRS cells. Proteins in cell culture supernatant of 4 HL cell lines were identified using 1DGE followed by in-gel trypsin digestion and LC-MS/MS. In total, 1290 proteins, including 368 secreted proteins, were identified. Functional grouping of secreted proteins revealed 37 proteins involved in immune response. Sixteen of the 37 proteins (ie, ALCAM, Cathepsin C, Cathepsin S, CD100, CD150, CD26, CD44, CD63, CD71, Fractal-kine, IL1R2, IL25, IP-10, MIF, RANTES, and TARC) were validated in HL cell lines and patient material using immunohistochemistry and/or ELISA. Expression of all 16 proteins was confirmed in HL cell lines, and 15 were also confirmed in HL tissues. Seven proteins (ALCAM, cathepsin S, CD26, CD44, IL1R2, MIF, and TARC) revealed significantly elevated levels in patient plasma compared with healthy controls. Proteomics analyses of HL cell line supernatant allowed detection of new secreted proteins, which may add to our insights in the interaction between HRS cells and infiltrating lymphocytes and in some instances might serve as biomarkers.  相似文献   
29.
30.
An adapted cow's milk infant formula without or with extra taurine (350 μmol/l) was fed to four and five infants, respectively. The infants, born after 28–32 weeks gestation, and initially fed with a starting formula for preterms, were switched to one of the two above-mentioned formulae at approximately the 16th day of life. Each infant was studied during 4 consecutive weeks. The faecal excretion of fat, energy and total bile acids was determined from 3-day stool collections each week. The addition of taurine to the infant formula neither improved the uptake of fat and energy nor changed the faecal bile acid excretion. Growth velocity was similar in both groups of infants. Based on these results there is no rationale for adding taurine to adapted cow's milk infant formula to obtain a better fat absorption.  相似文献   
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