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51.
Prof. Dr. F. Wenz V. Steil C. Herskind H. Sommer K. Friese M. Sütterlin U. Kraus-Tiefenbacher 《Der Gyn?kologe》2007,40(6):463-466
Intraoperative radiotherapy (IORT) delivered to the tumor bed using the INTRABEAM system (Carl Zeiss, Oberkochen, Germany) during breast-conserving surgery is currently being tested in a prospective randomized trial (TARGIT) in highly selected patients. Patients (>50 years of age) with unifocal ductal invasive carcinoma (<2 cm) can be included. External beam radiotherapy to the whole breast is compared with single-dose IORT, which is supplemented by external beam radiotherapy only when risk factors (extensive intraductal component (EIC), lymph vessel invasion, free margin <1 cm) are present. The rationale behind the study and the complex physical and radiobiological implications of IORT with low-energy X-rays are discussed. 相似文献
52.
GM Durbin NJ Hunter N McIntosh EO Reynolds PD Wimberley 《Archives of disease in childhood》1976,51(3):163-169
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131). 相似文献
53.
S Thavagnanam SN Christie GM Doherty PV Coyle MD Shields LG Heaney 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(3):394-398
Aim: The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children. Methods: Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed. Results: Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03). Conclusions: Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children. 相似文献
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Closed-loop insulin delivery in individuals with diabetes can potentially lead to near-normal glucose profiles. To this end, existing subcutaneous glucose sensors and external insulin pumps can be linked with an insulin delivery algorithm to create a completely automated closed-loop system. This paper reviews current research into the development of such a system, with particular emphasis on creating a system emulating the physiological properties of the beta-cell. Issues related to using subcutaneous interstitial fluid for glucose sensing and insulin delivery are reviewed. Criteria for optimising the system are discussed using historical data. Existing strategies for open-loop pump therapy are presented with the objective of defining a path to advance from the existing physician/patient determined insulin therapy to a completely automated system. 相似文献
56.
Jeroen SL de Munter Irene GM van Valkengoed Charles Agyemang Anton E Kunst Karien Stronks 《The international journal of behavioral nutrition and physical activity》2010,7(1):1-8
Purpose
The level of recommended physical activity (PA) is met less frequently by people from some ethnic minorities than others. We explored whether these differences in recommended PA between ethnic minority groups and the general population varied by domain and type of culturally-specific activity.Methods
Participants were sampled from the population based SUNSET study and were from ethnic Dutch (n = 567), Hindustani-Surinamese (n = 370) and African-Surinamese (n = 689) descent. The validated SQUASH-questionnaire measured PA for the following domains: commuting, occupation, household, leisure time. Culturally-specific activities were added as extra question within the leisure time domain. The effect of each domain on ethnic differences in recommended PA prevalence was examined by odds-ratio (OR) analysis through recalculating recommended PA, while, in turn, excluding the contribution of each domain.Results
In the ethnic Dutch population, more vigorous PA in commuting and leisure time was reported compared to the Surinamese groups. The Hindustani-Surinamese and African-Surinamese reported more walking as commuting activity, while the Dutch group reported cycling more frequently. Ethnic differences in recommended PA became smaller in both Surinamese groups compared with the Dutch after removing commuting activity, for example, in Hindustani-Surinamese men (OR = 0.92, 95%CI: 0.62-1.37 vs. OR = 1.33, 0.89-2.00) and women (OR = 1.61, 1.12-2.32 vs. OR = 2.03, 1.41-2.92). Removing occupational activity resulted in larger ethnic differences in both groups compared with the Dutch. Smaller effects were found for yoga and dancing, leisure time and household activities.Conclusion
This study shows that differences in PA between ethnic minority groups and the general population vary according to the activity domain. The results indicate that including all relevant domains and activities is essential for assessment of ethnic differences in recommended PA. 相似文献57.
Chronic pancreatitis: ultrasonic features 总被引:2,自引:0,他引:2
A retrospective analysis of 84 ultrasound examinations (in 77 patients) was performed to assess the frequency of sonographic findings in chronic pancreatitis. The findings included: inhomogeneously increased echogenicity in 53% of these examinations, focal or diffuse enlargement in 41%, focal dense echoes in 40%, pseudocyst formation in 21%, and a hypoechoic head mass in 7%. Thirteen per cent of our patients had a normal sonogram. Several presentations of chronic pancreatitis not previously described in the sonographic literature included: pancreatic or common bile duct enlargement or pseudocyst formation with otherwise normal-appearing glands. There was no direct relationship between the presence of focal high-intensity echoes within the pancreatic parenchyma and the presence of radiographic calcification. There was no difference in the frequency of ultrasonic abnormalities between patients with and without clinical evidence of pancreatic insufficiency. These results indicate that the sonographic findings in chronic pancreatitis are significantly more varied than previous reports would indicate. 相似文献
58.
dos Santos SC Krueger CL Steil AA Kreuger MR Biavatti MW Wisniewski Junior A 《Planta medica》2006,72(8):679-684
The leaves of guaco (Mikania glomerata and M. laevigata) are widely used for the treatment of asthma and bronchitis. An LC method for the quantification of coumarin and O-coumaric acid in medicinal extracts was developed and validated for linearity, limit of detection, accuracy, precision, as well as intra- and inter-day variations. Extracts and isolated markers were tested in the mice allergic pneumonitis model and the histopathological profile of the lung tissue was analysed. The values found for coumarin and O-coumaric acid in a fluid extract were 1.53 and 1.69 mg/mL, respectively, for M. glomerata, and 0.96 and 0.38 mg/mL for M. laevigata. The values found for the lyophilised aqueous extract were 0.22 and 0.11 mg/mL of coumarin and O-coumaric acid in M. glomerata and 0.05 and 0.02 mg/mL in M. laevigata, respectively . The analysed samples from the species M. glomerata presented more coumarin and O-coumaric acid than the analogous M. laevigata species. Both coumarin and O-coumaric acid are part of the phytocomplex which is responsible for the therapeutic activity of the guaco species. The lyophilisation process generated some alterations in the extract, in comparison with the fresh aqueous extract, and these extracts did not present anti-inflammatory activity. Comparing the histopathological images of the groups tested, a haemorrhagic profile of lung tissue of animals treated with lyophilised extract, O-coumaric acid and coumarin is observed, but not for the group treated with hydroalcoholic extract. It is probable that some protective effect of the whole extract (lost during the lyophilisation process) blocks the harmful effects of the isolated markers. 相似文献
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