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1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors. 相似文献
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AimsTo investigate the seasonal variations of HbA1c values in a semi-arid climate among type 2 diabetic patients throughout 11 years of care.MethodsA retrospective cohort study of 2860 patients with 61,187 HbA1c measures. We calculated the averages of HbA1c values of all patients and sub-groups defined by age, gender, BMI, ethnicity, insulin use, smoking status and region of residence, matched to the mean temperature and diurnal range over the 30 and 60 days prior to the HbA1c test date.ResultsWe found a sinusoidal seasonal pattern with statistically significant HbA1c levels gaps between the spring peak and the autumn trough (F = 18.4, P < 0.001). The lowest values were in October-November and the highest in March or August with a difference of 0.17–0.31% (2–4 mmol/mol). We found different relations between the mean temperature and HbA1c depending on season, gender, age, ethnicity and smoking habits.ConclusionThe study identified specific subgroups in which the seasonal influence is particularly marked. A possible explanation is that during hot periods people tend to change their diet and decrease their physical activity, effecting indirectly diabetic imbalance. Recognition of the seasonal variations of HbA1c levels in this geographical region could help physicians with diabetes care and HbA1c control. 相似文献
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《Journal of neonatal nursing : JNN》2020,26(2):120-122
Background and objectiveReports on expenses to families of extreme preterm babies are scarce. Charges may vary based on regional socio-economic conditions. Systematic auditing of hospital care costs helps families develop a tangible feel of expected expenses. It also allows the medical team to identify areas where costs can be reduced. We studied expenses borne by the families towards care of an extreme preterm neonate during hospital stay.MethodsNeonates who were delivered <28 weeks and who completed care till discharge in the unit were included. The bills to the family were retrospectively analysed.ResultsThe median per day charge borne by the family was USD 107.4 (IQR 94.6–135.5). The median total cost to the patient was USD 9446.5. Maximum proportion of the costs were towards nursing charges.ConclusionsThe average per day charges was USD 107.4 (IQR 94.6–135.5). Stringent efforts should be made by the health care teams to optimise the costs to families. Neonatal intensive care needs to be commercially viable as well. 相似文献
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《Transfusion and apheresis science》2020,59(6):102908
IntroductionTemperature and time conditions during storage and distribution of blood components (BC) and their permissible deviations are strictly regulated. The degree of compliance with these requirements in daily practice of transfusion services (TS) is not well known.Materials and methodsWe conducted a survey among Spanish hospital TS covering different aspects of BC management in their daily activity.ResultsEighty-three TS managing 56 % of total transfusions answered the survey. Monitoring of red blood concentrates (RBC) temperature during in-hospital distribution was routinely performed by only 12 % of the TS. The main criterion for BC re-entry into the stock was the total time spent outside controlled temperature. Up to 41 % of the TS apply the “30-minute rule” to distributed RBC, while most services use a 60-minute rule for PC. No adverse events were detected when RBC that had remained longer than 30 or 60 min outside the TS were transfused. Fresh frozen plasma is usually thawed 2 h preissue and stored at 4 °C up to 24 h.Discussion and conclusionsIn the Spanish context, the 30- and 60-minute rules for re-entry of RBC and PC into the TS stock are loosely followed. Feedback for a large number of TS suggests that the extension of the 30-minute RBC rule to at least 60 min is feasible, if other safety requirements are met. Flexibility with some requirements could help reduce product loss without deleterious effect on BC safety. 相似文献
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BackgroundIt is not known if the tremor associated with an epidural top-up dose for intrapartum caesarean delivery is thermoregulatory shivering. A tremor is only shivering if it has the same frequency profile as cold stress-induced shivering. Thermoregulatory shivering is a response to a reduction in actual body temperature, whereas non-thermoregulatory shivering may be triggered by a reduction in sensed body temperature. This mechanistic study aimed to compare: 1. the frequency profiles of epidural top-up tremor and cold stress-induced shivering; and 2. body temperature (actual and sensed) before epidural top-up and at the onset of tremor.MethodsTwenty obstetric patients received an epidural top-up for intrapartum caesarean delivery and 20 non-pregnant female volunteers underwent a cold stress. Tremor, surface electromyography, core temperature, skin temperature (seven sites) and temperature sensation votes (a bipolar visual analog score ranging from −50 to +50 mm) were recorded.ResultsThe mean (SD) primary oscillation (9.9 (1.9) Hz) frequency of epidural top-up tremor did not differ from that of cold stress-induced shivering (9.0 (1.6) Hz; P=0.194), but the mean (SD) burst frequency was slower (6.1 (1.2) × 10−2 Hz vs 6.9 (0.7) × 10−2 Hz, respectively; P=0.046). Before the epidural top-up dose, the mean (SD) core temperature was 37.6 (0.6) °C. Between the epidural top-up dose and the onset of tremor the mean (SD) core temperature did not change (–0.1 (0.1) °C; P=0.126), the mean (SD) skin temperature increased (+0.4 (0.4) °C; P=0.002) and the mean (SD) temperature sensation votes decreased (−12 (16) mm; P=0.012).ConclusionThese results suggest that epidural top-up tremor is a form of non-thermoregulatory shivering triggered by a reduction in sensed body temperature. 相似文献
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《Journal of the Academy of Nutrition and Dietetics》2020,120(10):1715-1721
BackgroundOne in six US households with children experiences food insecurity, with higher rates in the summer. Approximately 3 million children receive free meals each summer weekday through the US Department of Agriculture’s Summer Nutrition Programs. However, participation in these programs has been declining in recent years and is lower than participation in programs that serve free or reduced-price meals during the school year.ObjectiveTo identify school and site characteristics associated with greater reach by school-based free summer meals program sites.DesignThis observational study combined program data, public school data, and Google Maps data to determine factors associated with site reach.Participants/settingLunchStop Summer Meals Program sites (N=100) and schools at which they were based during summer 2018 in Chicago, IL.Main outcome measuresReach of sites was measured by the mean daily meals served at each site throughout summer 2018.Statistical analyses performedAssociations between site reach and each independent variable were evaluated using Mann-Whitney tests and simple linear regressions. Variables significantly associated with site reach in bivariate analyses (P<0.05) were included in a multivariate linear regression.ResultsIn bivariate analyses, sites with greater reach were significantly more likely to be based at schools with higher attendance percentages, higher percentages of Hispanic/Latino students, larger student populations, and locations in a network of southwest Chicago schools. Those with greater reach were also significantly more likely to have continuity in program staff and more years of site operation (all P values ≤0.01). The last four factors remained significant in multivariate analysis.ConclusionsSchool-based summer meals programs may be able to reach more vulnerable children by taking into account continuity among sites and staff. Further research is needed to clarify whether the relationships between these variables and increased reach is causal. 相似文献
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目的:测量热牙胶充填系统携热头工作状态下的实际温度,为临床研究热损伤、观察温度升高对充填材料影响提供理论依据。方法:使用双通道K型电偶温度计测量3种热牙胶充填系统的不同大小携热头和携热头不同部位(工作端尖端和距尖端2 mm、5 mm、10 mm处)的实际温度(设置温度200 ℃),重复测量5次,比较不同充填系统、不同携热头大小、不同测量位点的实际工作温度和设置温度的差异,并用单因素方差分析法分析各因素的影响。结果:BeeFill 40/0.03携热头尖端工作温度最高(198.7±7.7)℃,与设定温度200 ℃差异无统计学意义(P>0.05),其余携热头工作温度均低于设定温度200 ℃,差异有统计学意义(P<0.05),BeeFill 60/0.06携热头距尖端10 mm处温度最低(69.9±4.0) ℃。所有携热头尖端(0 mm)及尖端2 mm处温度较高(112.1~198.7 ℃,中位数140.8 ℃)。结论:大部分热牙胶充填系统的携热头实际工作温度低于设定温度200 ℃。 相似文献
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《Urologic oncology》2015,33(4):168.e1-168.e7
ObjectiveAlthough tissue ablation by irreversible electroporation (IRE) has been characterized as nonthermal, the application of frequent repetitive high-intensity electric pulses has the potential of substantially heating the targeted tissue and causing thermal damage. This study evaluates the risk of possible thermal damage by measuring temperature development and distribution during IRE of porcine kidney tissue.MethodsThe animal procedures were conducted following an approved Institutional Animal Ethics Committee protocol. IRE ablation was performed in 8 porcine kidneys. Of them, 4 kidneys were treated with a 3-needle configuration and the remaining 4 with a 4-needle configuration. All IRE ablations consisted of 70 pulses with a length 90 µs. The pulse frequency was set at 90 pulses/min, and the pulse intensity at 1,500 V/cm with a spacing of 15 mm between the needles. The temperature was measured internally using 4 fiber-optic temperature probes and at the surface using a thermal camera.ResultsFor the 3-needle configuration, a peak temperature of 57°C (mean = 49±10°C, n = 3) was measured in the core of the ablation zone and 40°C (mean = 36±3°C, n = 3) at 1 cm outside of the ablation zone, from a baseline temperature of 33±1°C. For the 4-needle configuration, a peak temperature of 79°C (mean = 62±16°C, n = 3) was measured in the core of the ablation zone and 42°C (mean = 39±3°C, n = 3) at 1 cm outside of the ablation zone, from a baseline of 35±1°C. The thermal camera recorded the peak surface temperatures in the center of the ablation zone, reaching 31°C and 35°C for the 3- and 4-needle configuration IRE (baseline 22°C).ConclusionsThe application of repetitive high-intensity electric pulses during IRE ablation in porcine kidney causes a lethal rise in temperature within the ablation zone. Temperature monitoring should be considered when performing IRE ablation near vital structures. 相似文献