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761.
This study reviews current food safety regulations of food trucks and discusses possible inspection challenges and reasons for gaps between food safety regulations and practices. To be able to assess current food regulations at the state level, the Florida Department of Health (FDOH) was selected and their current materials and documents, publicly available on the DOH website, were briefly examined. This paper highlights possible reasons for safety risks and gaps between theory and application. Food regulations, inspection challenges, mobility of trucks, vendors’ personal hygiene, undocumented illnesses, temperature violations, and unlicensed trucks can be listed as potential gaps and safety risks. Regardless of the level of strict inspection facilities offered to the vendors, there are still incomplete and unsatisfactory results displayed in the county health department (CHD) webpages as open data. This review article shows that even though the United States Department of Agriculture (USDA), the Food and Drug Administration (FDA), and local health departments control safety regulations, street food operations still face great challenges and public health issues in Florida, as well as in many states in the United States. 相似文献
762.
Ozdemir Yalcinsoy Kubra Ozdamar Erol Yasemin Tekin Kemal Inanc Tekin Merve Sonmez Kenan 《International ophthalmology》2022,42(4):1289-1297
International Ophthalmology - To evaluate and compare the effects of different intraocular tamponade agents on lens density after vitrectomy. The participating patients were divided into four... 相似文献
763.
Objective:
This study compared the dosimetry of volumetric-arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) with a dynamic multileaf collimator using the Monte Carlo algorithm in the treatment of prostate cancer with and without simultaneous integrated boost (SIB) at different energy levels.Methods:
The data of 15 biopsy-proven prostate cancer patients were evaluated. The prescribed dose was 78 Gy to the planning target volume (PTV78) including the prostate and seminal vesicles and 86 Gy (PTV86) in 39 fractions to the intraprostatic lesion, which was delineated by MRI or MR-spectroscopy.Results:
PTV dose homogeneity was better for IMRT than VMAT at all energy levels for both PTV78 and PTV86. Lower rectum doses (V30–V50) were significantly higher with SIB compared with PTV78 plans in both IMRT and VMAT plans at all energy levels. The bladder doses at high dose level (V60–V80) were significantly higher in IMRT plans with SIB at all energy levels compared with PTV78 plans, but no significant difference was observed in VMAT plans. VMAT plans resulted in a significant decrease in the mean monitor units (MUs) for 6, 10, and 15 MV energy levels both in plans with and those without SIB.Conclusion:
Dose escalation to intraprostatic lesions with 86 Gy is safe without causing serious increase in organs at risk (OARs) doses. VMAT is advantageous in sparing OARs and requiring less MU than IMRT.Advances in knowledge:
VMAT with SIB to intraprostatic lesion is a feasible method in treating prostate cancer. Additionally, no dosimetric advantage of higher energy is observed.Randomized trials have shown a gain in biochemical relapse-free survival using dose escalation for prostate cancer.1 However, isolated local failure is still reported in nearly one-third of patients, even with higher radiotherapy (RT) doses.1 Local recurrence is of clinical importance because a relationship has been suggested between local control, distant metastasis and survival.2 It has also been demonstrated that intraprostatic failure mainly originates at the initial tumour location as a result of intrinsic resistance of a fraction of the tumour clones, which implies that selective dose escalation to the dominant intraprostatic lesion using simultaneous integrated boost (SIB) might be beneficial.3With new RT techniques, such as intensity-modulated RT (IMRT) and volumetric-arc therapy (VMAT), SIB could be delivered without increasing acute toxicity.4–7 Several recent studies have performed dosimetric comparison of IMRT and VMAT plans in prostate cancer;8–10 however, dosimetric evaluation of IMRT and VMAT plans delivering SIB is rare. In these studies, target volume and organs at risk (OARs) doses may vary with different treatment planning systems. Another aspect not often addressed in these planning studies is the photon energy level.4,8,9,11 Although higher energy photons have the potential advantage of reduced attenuation with depth, this may in turn increase the risk of secondary malignancies because of the presence of neutrons generated in the accelerator head at treatment energies >8 MV.12Functional imaging techniques can clearly demonstrate tumour within the prostate. MRI, MR spectroscopy (MRS) and positron emission tomography are capable of demonstrating intraprostatic lesions (IPLs).13 The advent of combined MRI with MRS or dynamic contrast enhanced (DCE)-MRI improves the detection rate of tumours within the prostate.13–15The aim of the present study was to make dosimetric comparisons of VMAT and 7-field IMRT with dynamic multileaf collimators (MLCs) using the Monte Carlo algorithm with XVMC code in the treatment of prostate cancer with or without SIB, which can provide improved dose calculation accuracy and has been implemented successfully in the clinical setting.16,17 Additionally, the impact of three photon energies on target volumes, OARs and normal tissue was evaluated in IMRT and VMAT plans. 相似文献764.
765.
Automated evaluation of parapapillary choroidal microvasculature in crowded optic discs: a controlled, optical coherence tomography angiography study
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Hatice Ard Hidayet Sener Ozge Temizyurek Hatice Kubra Sonmez Duygu Gulmez Sevim Cem Evereklioglu Fatih Horozoglu Ayse Busra Gunay Sener 《国际眼科》2024,17(1):113-118
AIM: To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography (OCT-A).
METHODS: Thirty patients with crowded discs, and 47 control subjects were enrolled in the study. One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm2 rectangular area. Radial peripapillary capillary (RPC) density, peripapillary retinal nerve fiber layer (pRNFL) thickness, cup volume, rim area, disc area, cup-to-disc (c/d) area ratio, and vertical c/d ratio were obtained automatically using device software. Automated parapapillary choroidal microvasculature (PPCMv) density was calculated using MATLAB software. When the vertical c/d ratio of the optic disc was absent or small cup, it was considered as a crowded disc.
RESULTS: The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes (P=0.740). There was no difference in pRNFL between the two groups (P=0.102). There were no differences in RPC density in whole image (P=0.826) and peripapillary region (P=0.923), but inside disc RPC density was higher in crowded optic discs (P=0.003). The PPCMv density in the inner-hemisuperior region was also lower in crowded discs (P=0.026). The pRNFL thickness was positively correlated with peripapillary RPC density (r=0.498, P<0.001). The inside disc RPC density was negatively correlated with c/d area ratio (r=-0.341, P=0.002).
CONCLUSION: The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs. 相似文献