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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   
2.
PurposeAssess multiparametric-MRI (mp-MRI) diagnostic accuracy in the detection of local recurrence of prostate cancer (PCa) after radical prostatectomy (PR) and before radiation therapy (RT).Materials and methodsA total of 188 patients underwent 1.5-T mp-MRI after RP before RT. Patients were divided into 2 groups: with biochemical recurrence (group A) and without but with high risk of local recurrence (group B). Continuous variables were compared between 2 groups using Student-t test; categoric variables were analyzed using Pearson chi-square. ROC analysis was performed considering PSA before RT, ISUP, pT and pN as grouping variables.ResultsPCa recurrence (reduction of PSA levels after RT) was 89.8% in group A and 80.3% in group B. Comparing patients with and without PCa recurrence, there was a significant difference in PSA values before RT for group A and for PSA values before RT and after RT for group B. In group A, there was a significant correlation between PSA before RT and diameter of recurrence and between PSA before RT and time spent before recurrence. The mp-MRI diagnostic accuracy in detecting PCa local recurrence after RP is of 62.2% in group A and 38% in group B. Diffusion weighted imaging is the most specific MRI-sequence and dynamic contrast enhanced the most sensitive. For PSA = 0.5 ng/ml, the AUC decreases while sensitivity and accuracy increase for each MRI-sequence. For PSA = 0.9 ng/ml, dynamic contrast enhanced-AUC increases significantly.Conclusionmp-MRI should always be performed before RT when a recurrence is suspected. New scenarios can be opened considering the role of diffusion weighted imaging for PSA  0.5 ng/ml.  相似文献   
3.
Background: Intraductal carcinoma and cribriform (IDC/C) tumor features are well-established prognosticators of biochemical recurrence (BCR), metastasis, and prostate cancer (PCa)-specific mortality. However, approximately 70% of PCa patients undergoing a radical prostatectomy are IDC/C negative, yet up-to 20% of these patients progress and experience BCR. Thus, tumor histopathologic characteristics such as IDC/C alone are limited in their ability to predict disease progression. Conversely, several nomograms such as Cancer of the Prostate Risk Assessment-Surgery (CAPRA-S) have been developed to aid in the prognostication of BCR, but not yet widely applied in clinical settings. Materials and methods: In this study, we assessed the combined prognostic utility of IDC/C, and CAPRA-S for BCR in 3 PCa patient cohorts. Results: CAPRA-S+IDC/C improved the predictive accuracy of BCR in all 3 cohorts (P < .001). Specifically, among IDC/C negative cases, CAPRA-S improved the prognostication of BCR in low-risk (Cohort 1; P < .001, Cohort 2; P < .001, Cohort 3; P = .003), intermediate (Cohort 1; P < .001, Cohort 2; P = .006, Cohort 3; P = .03) and high-risk (Cohort 1-3; P < .001) patients. Conversely, IDC/C improved the prognostication of BCR among CAPRA-S low-risk (Cohorts 1; P < .001 and Cohort 3; P = .003) patients. Conclusion: Our results suggest the investigation of histopathological IDC/C features in CAPRA-S low-risk patients and conversely, nomogram CAPRA-S among IDC/C negative patients improves the identification of patients likely to experience BCR, which would otherwise be missed through current assessment regimens. These patients can be offered more intensive monitoring and adjuvant therapies upfront to circumvent the development of recurrent cancer or overtreatment at the time of surgery.  相似文献   
4.
5.
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa.  相似文献   
6.
生化自动分析仪在进行噪音核查和反应限核查之前,均已完成线性核查,已确定线性反应区,从吸光度-时间回归线计算出每分钟吸光度变化速度(△A/min)。在此基础上进行噪音核查(Noise Check)和反应限核查(Reaction Limit Check)。  相似文献   
7.
Urinary 5-hydroxytryptophol (5-HTOL) is currently being evaluated as a marker of recent alcohol consumption. To compensate for urinary dilution, the molar ratio between 5-HTOL and 5-hydroxyindole-3-acetic acid (5-HIAA) is used. The 5-HTOL/5-HIAA ratio showed a satisfactory degree of individual stability when it was followed in a group of teetotallers for 1 month. The mean value of 5-HTOL/5-HIAA in a group of 69 persons abstaining from alcohol was 7.6 (pmoles 5-HTOL/nmoles 5-HIAA). Ninety-seven percent had values ranging from 4 to 17, with no value exceeding 20. A group of healthy volunteers were tested 12 hr after alcohol consumption and showed a dose-dependent and statistically significant elevation in the 5-HTOL/5-HIAA ratio. Four regular alcohol consumers who were followed during a period of 3 months of drinking had elevated values of the 5-HTOL/5-HIAA ratio in 60% of their urine samples. The present study indicates that urinary 5-HTOL/5-HIAA is a sensitive and reliable marker of recent alcohol consumption. We propose that a 5-HTOL/5-HIAA ratio greater than 20 (pmoles/nmoles) can be used to indicate recent alcohol consumption. This limit gives a low frequency of false positives; the statistical probability of having a value greater than 20 during abstinence from alcohol was calculated to be less than 0.001.  相似文献   
8.
本文将生化自动分析仪应用于健康检诊中,就其中1089名健康者的血清进行12项生化指标的检测,并对测得的结果进行分析整理,确定国人的正常值范围。同时又对自动分析仪的质量管理进行了探讨。  相似文献   
9.
VRML metabolic network visualizer   总被引:1,自引:0,他引:1  
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10.
Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals.  相似文献   
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