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1.
At a radiotherapy department cancer patients are treated with high energy electron and photon beams. These beams are produced by a linear accelerator. A closed circuit television system is used to monitor patients during treatment. Although CCD cameras are rather resistant to stray radiation, they are damaged by the low flux of neutrons which are produced by the linac as a side effect. PVC can be used to reduce damage to CCD cameras induced by neutron radiation. A box with 6 cm thick walls will extend the life of the camera at least by a factor of two. A PVC neutron shield is inexpensive. PVC is easy to obtain and the box is simple to construct. A similar box made out of PE will not reduce neutron damage to a CCD camera. Although PE is a good medium to moderate faster neutrons, thereby reducing some of the bulk defects, it will not capture thermal neutrons which induce surface damage.  相似文献   
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BackgroundIn patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations.MethodsBlood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV).ResultsBH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher.ConclusionBH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis.  相似文献   
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Purpose

To evaluate the rate and pattern of recurrences after neoadjuvant chemoradiotherapy (CRT) in esophageal cancer patients.

Methods

We described survival and differences in recurrences from a single center between neoadjuvant CRT (carboplatin/paclitaxel and 41.4 Gy) and surgery alone for the period 2000–2011. To reduce bias, we performed a propensity score matched analysis.

Results

A total of 204 patients were analyzed, 75 treated with neoadjuvant CRT and 129 with surgery alone. The pathologic response to neoadjuvant CRT was 69 % with a complete response rate of 25 %. After matching, baseline characteristics between the groups (both n = 75) were equally distributed. The 3- and 5-year disease-free survival was 53 and 42 % in the neoadjuvant CRT group compared with 24 and 18 % in the surgery-alone group (P = 0.011). After 3 and 5 years’ CRT, patients had an estimated locoregional recurrence-free survival of 83 and 73 % compared with 52 and 49 % in the surgery-alone group (P = 0.015). The distant recurrence-free survival was comparable in both groups. Locoregional recurrences were located less in the paraesophageal lymph nodes in the CRT group than in the surgery-alone group, 9 versus 21 %, respectively (P = 0.041). With respect to differences in distant recurrences, we observed more skeletal recurrences in the surgery-alone group compared to CRT, 12 versus 1 % (P = 0.009).

Conclusions

The neoadjuvant CRT regimen we used offers a significant improvement in outcome, with a different recurrence pattern compared with surgery alone. This effect is probably due to both the pathologic complete response and eradication of micrometastases in CRT group.  相似文献   
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Complement activation is of major importance in numerous pathological conditions. Therefore, targeted complement inhibition is a promising therapeutic strategy. C1‐esterase inhibitor (C1‐INH) controls activation of the classical pathway (CP) and the lectin pathway (LP). However, conflicting data exist on inhibition of the alternative pathway (AP) by C1‐INH. The inhibitory capacity of C1‐INH for the CP is potentiated by heparin and other glycosaminoglycans, but no data exist for the LP and AP. The current study investigates the effects of C1‐INH in the presence or absence of different clinically used heparinoids on the CP, LP and AP. Furthermore, the combined effects of heparinoids and C1‐INH on coagulation were investigated. C1‐INH, heparinoids or combinations were analysed in a dose‐dependent fashion in the presence of pooled serum. Functional complement activities were measured simultaneously using the Wielisa®‐kit. The activated partial thrombin time was determined using an automated coagulation analyser. The results showed that all three complement pathways were inhibited significantly by C1‐INH or heparinoids. Next to their individual effects on complement activation, heparinoids also enhanced the inhibitory capacity of C1‐INH significantly on the CP and LP. For the AP, significant potentiation of C1‐INH by heparinoids was found; however, this was restricted to certain concentration ranges. At low concentrations the effect on blood coagulation by combining heparinoids with C1‐INH was minimal. In conclusion, our study shows significant potentiating effects of heparinoids on the inhibition of all complement pathways by C1‐INH. Therefore, their combined use is a promising and a potentially cost‐effective treatment option for complement‐mediated diseases.  相似文献   
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Unreliable spinal X-ray radiography measurement due to standing postural variability can be minimized by using positional supports. In this study, we introduce a balancing device, named BalancAid, to position the patients in a reproducible position during spinal X-ray radiography. This study aimed to investigate the performance of healthy young subjects’ standing posture on the BalancAid compared to standing on the ground mimicking the standard X-rays posture in producing a reproducible posture for the spinal X-ray radiography. A study on the posture reproducibility measurement was performed by taking photographs of 20 healthy young subjects with good balance control standing on the BalancAid and the ground repeatedly within two consecutive days. We analyzed nine posterior–anterior (PA) and three lateral (LA) angles between lines through body marks placed in the positions of T3, T7, T12, L4 of the spine to confirm any translocations and movements between the first and second day measurements. No body marks repositioning was performed to avoid any error. Lin’s CCC test on all angles comparing both standing postures demonstrated that seven out of nine angles in PA view, and two out of three angles in LA view gave better reproducibility for standing on the BalancAid compared to standing on the ground. The PA angles concordance is on average better than that of the LA angles.  相似文献   
7.
In the assessment of mucositis, the inter-evaluator variability needs to be minimised and would likely to be best accomplished by training. The aim of this study was to evaluate the effect of training on concordance of evaluators in scoring oral mucositis. The evaluators were informed about the pathobiology and clinical appearance of mucositis and were trained in scoring mucositis according the Oral Mucositis Assessment Scale (OMAS). The effect of the training was evaluated by a pre- and post-training test. Each test consisted of 15 slides depicting oral mucositis. The pre- and post-training scores were compared to the reference standard. During 8 months at 6 meetings, 65 evaluators were trained. The mean percentage correctly scored slides according the OMAS increased significantly between the pre- and post-training test (P<0.001). Training evaluators in scoring oral mucositis has a significant improvement on the outcome of mucositis assessment.  相似文献   
8.
BACKGROUND: No study has yet investigated the validity of prescreening by albumin measurements in a spot morning urine sample to identify in the general population subjects with microalbuminuria. We therefore tested the diagnostic performance of urinary albumin concentration (UAC) and albumin-creatinine ratio (ACR), measured in a spot morning urine sample, in predicting a urinary albumin excretion (UAE) > or =30 mg in subsequent 24-hour urines (microalbuminuria). METHODS: Subjects (2527) participating in the PREVEND study, a representative sample from the general population, collected a spot morning urine sample and, on average, 77 days later, two 24-hour urine collections. RESULTS: The ROC curve of UAC in predicting microalbuminuria has an area-under-the-curve of 0.92 with a discriminator value of 11.2 mg/L. Using this cut-off value for UAC, sensitivity in predicting microalbuminuria is 85.0%, and specificity 85.0%. For ACR these values are, respectively: area-under-the-curve 0.93, discriminator value 9.9 mg/g, sensitivity 87.6%, and specificity 87.5%. Sensitivity for UAC in predicting microalbuminuria does not differ significantly from the sensitivity for ACR, whereas the difference between the specificities of UAC and ACR reaches statistical significance, but is numerically very small. In various subgroups characterized by differences in urinary creatinine excretion, the area-under-the-ROC curve, sensitivity, as well as specificity, do not increase relevantly compared to the results in the overall study population. This holds true for ACR as well as UAC. CONCLUSION: The diagnostic performance of measuring UAC in a spot morning urine sample in predicting microalbuminuria in subsequent 24-hour urine collections is satisfactory, and, moreover, comparable to that of measuring ACR. In order to keep the burden and costs involved in population screening for microalbuminuria as low as possible, we therefore propose prescreening by measuring UAC in a spot morning urine sample. Those subjects with a UAC above a certain predefined level (e.g., 11 mg/L) should be asked to collect timed urine samples.  相似文献   
9.
Cardiovascular morbidity and mortality is not equally distributed among genders, men being more affected than women. It is not clear whether this is only related to a higher prevalence of the cardiovascular risk factors or to a similar prevalence of the risk factors as in women but a greater vascular susceptibility to these risk factors in men. This was tested by studying the association between various cardiovascular risk factors and urinary albumin excretion (UAE) in a large cohort of male and female subjects. While the prevalence of smoking and hypercholesterolemia was comparable between the genders, obesity was more common in women, and diabetes and hypertension were more frequent in men. The prevalence of microalbuminuria was about twofold higher in men. Interestingly, for a given level of any risk factor, UAE was higher in men than in women. On multivariate analysis with UAE as the dependent variable, an interaction with gender was found for the risk factors age, body mass index, and plasma glucose. Thus, for a higher age, body mass index, and glucose, the UAE is significantly increased in men when compared with women. It is concluded that gender differences exist in the association between cardiovascular risk factors and UAE. This is consistent with a larger vascular susceptibility to these risk factors in men as compared with women.  相似文献   
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