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321.
Definitive radiotherapy is an effective single-modality in T1 glottic cancer. Hypofractionated schemes could offer excellent results in a shorter treatment period. We aimed to evaluate the clinical outcomes and toxicity comparing conventional vs. hypofractionated radiotherapy treatment in T1N0M0-glottic cancer. Between Jan-1st, 2005 and August-1st, 2017, in a prospective cohort study, with 10-year follow-up, 138 patients were treated with conventional schedule 2 Gy/day, total dose 70 Gy/7 weeks (N = 71) or hypofractionated schedule 2, 2–2, 25 Gy/day, total dose 63, 8–63 Gy/5, 5 weeks (N = 67). Endpoints were clinical-response rate, local relapse-free survival (LRFS), laryngectomy-free survival (LFS), toxicity rates, relapse-free survival (RFS), metastasis-free survival (MFS), second tumour-free survival (2TFS), and overall survival (OS). All patients showed a complete clinical response. No differences were found for LRFS (p = 0.869), LFS (p = 0.975), RFS (p = 0.767), MFS (p = 0.601), 2TFS (p = 0.293), or OS (p = 0.685). Acute toxicity for skin and mucosae was similar (p = 0.550 and p = 0.698). Acute laryngeal toxicity was higher in the hypofractionation group (p = 0.004), due to an increase in slight moderate grade. No differences in late laryngeal edema were found (p = 0.989). Radiotherapy offers high rate survival, local control, and larynx preservation after 5–10-year follow-up. A hypofractionation could be preferable, since it offers the same results as conventional with fewer treatment sessions.  相似文献   
322.
323.
Chronic transplant dysfunction is a complex dynamic pathogenic process. Clinically, a decrease in glomerular filtration rate (GFR) becomes apparent leading to chronic renal insufficiency and dialysis or death from cardiovascular events. Chronic transplant dysfunction can develop into a chronic alIograft nephropathy (CAN) as a specific entity with dynamic progression. CAN includes a collection of immunologic and non-immunologic factors, rejection, ischemia time, donor and recipient characteristics and toxicity of calcineurin inhibitors. Despite improvements in immunosuppression, the long-range prognosis of renal allografts has not improved. Whether modern immunosuppressive concepts with reduction or avoidance of calcineurin inhibitors and a therapy based on antimetabolites, such as mycophenolate or mTOR-inhibitors could lead to a prolongation of transplant survival, remains to be seen.  相似文献   
324.
The incidence of hematological malignancies during pregnancy is low, and treatment in this setting is problematic. This study observed 21 pregnancies in 18 patients with hematological malignancies. Patients’ ages were between 19 and 43 (median 25) years. Two pregnancies ended with spontaneous abortion, one pregnancy ended with in utero death, three therapeutic abortions were carried out, and 15 infants were born alive but three of them died later. The median birth weight was 2.47 kg. Twelve babies survived to a median age of 36 (range 4–117) months. Eight babies were exposed to chemotherapy during the in utero period. One baby was exposed to chemotherapy during all the trimesters and was born prematurely and later died because of intracranial bleeding. Four babies were exposed to chemotherapy during the first trimester, one of them had low birth weight and floating thumb malformation, two of them had only low birth weight, and one was born healthy, but died at 3 months of age as a result of severe gastroenteritis. Two babies were exposed to chemotherapy during the second and third trimesters; one of them had low birth weight, and the other pregnancy ended in in utero death. One infant was exposed to chemotherapy during the third trimester and was born at term, but died because of pulmonary hemorrhage. We concluded that chemotherapy during all trimesters of pregnancy carries a significant risk for an unfavorable outcome.  相似文献   
325.
Cytogenetic abnormalities are observed in approximately two‐thirds of patients with acute myeloid leukemia (AML). Chromosome rearrangements are associated with specific subtypes of AML and associated prognosis. We report a patient with AML, M2, who was primarily refractory to standard induction chemotherapy with idarubicin and cytarabine. Flow cytometry of a bone marrow aspirate showed aberrant expression of B‐cell markers including CD19. Cytogenetic studies disclosed a translocation between 5q35 and 11q13. Fluorescence in situ hybridization analyses demonstrated that neither the NSD1 nor MLL genes were involved in this case. Further study is required to define conclusively the genes involved and their contribution to pathogenesis in this case.  相似文献   
326.
327.
Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes.  相似文献   
328.
We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model.  相似文献   
329.
Summary We present a case of blindness and Anton’s syndrome in a psychiatric patient with late diagnosis of a giant frontal meningioma. The criteria for advanced diagnostic imaging in the psychiatric population are discussed. We conclude that MR or CT scan is indicated in psychiatric in-patients who fail to improve with standard psychiatric treatment. This strategy should be submitted to a cost-benefit analysis.  相似文献   
330.
BACKGROUND: The laparoscopic resection of rectal cancer shows morbidity and oncological safety comparable to the open approach, but morbidity increases after conversion to open resection. No oncological long-term results are available for the latter patients. METHODS: From 01/01/2000-31/12/2002, patients with curatively resected rectal cancer enrolled in a observational study were evaluated for morbidity, mortality, tumor- and local recurrence rate, paying attention to patients with conversion from laparoscopic to open resection. RESULTS: 237 (3.3%) of 7,189 patients underwent laparoscopic resection (ITT). These patients showed significantly more T1/2 tumors (P<0.001) in earlier UICC stages (P<0.001) than open resected patients. 35 (14.8%) of 237 laparoscopic procedures were converted. Compared with patients receiving complete laparoscopic or open resection, these patients showed significantly higher frequencies of intraoperative (P<0.001) and general postoperative complications (P=0.003) as well as the highest overall morbidity (P=0.031). After a median follow-up of 30.1 months, the highest 5-year local recurrence rate was found in the converted group (16.0%). The laparoscopically resected patients showed a local recurrence rate of 3.3%, patients with open resection of 12.4% (P=0.082). The disease-free survival rate did not differ between the groups (P=0.585). CONCLUSION: Laparoscopic resection of rectal cancer provides oncological results similar to open resection. After conversion, the short and oncological long-term outcomes were worse. Considering a conversion rate of 15%, only a strict indication for the laparoscopic approach can be allowed, and laparoscopic resection should be performed at centers.  相似文献   
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