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41.
42.
The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose–volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients.  相似文献   
43.
The effects of temperature and background counterions on ion-exchange selectivity for alkali metal ions and tetraalkylammonium ions on strongly acidic cation-exchange resins have been investigated using superheated water ion-exchange chromatography (SW-IEC). We have found out that alkali metal ions show reversal in the order of the distribution coefficient (KD), from Li+ < Na+ < K+ < Rb+ in water at ordinary temperature to Rb+ < K+ < Na+ < Li+ in superheated water, when a relatively large cation such as cesium ion is used as the background counterion. The effect of counterion on the ion-exchange selectivity is enhanced with the ion-exchange resins of higher ion-exchange capacity and cross-linking degree. Tetraalkylammonium ions chosen as model ions for poorly hydrated ions also exhibit reversal in the order of KD at around 430 K in superheated water. However, the effect of the nature of alkali metal counterions on the change in KD values of tetraalkylammonium ions is rather small compared with the effect on the KD of alkali metal ions. These results are attributed to the change in local hydration structures of the ions in the ion-exchange resin due to dehydration of alkali metal ions enhanced by interionic contacts of the analyte ion with the coexisting counterion and lower hydration energy of the ions at elevated temperatures. Although it has been considered that temperature is not effective at changing the ion-exchange separation selectivity, significant selectivity changes can be achieved by SW-IEC.

Metal ions in cation-exchange resins are dehydrated by interionic contacts with a co-existing counterion at elevated temperatures, which causes a drastic change in separation selectivity.  相似文献   
44.
We herein report a 65-year-old man with progressive multifocal leukoencephalopathy (PML) after 2-year remission from acute myeloid leukemia who developed recurrent episodes of left hemiparesis with gadolinium enhancement on magnetic resonance imaging. Steroid pulse therapy for each exacerbation induced clinical and radiological improvement, suggesting that exacerbations are an excessive immune response to the JC virus and distinct from immune reconstitution inflammatory syndrome (IRIS). Although glucocorticoids are recommended only for IRIS, steroid pulse therapy should be considered as a therapeutic option in cases of exacerbation of hematologic malignancy-associated PML. Importantly, neuroimaging is not sufficient to differentiate excessive inflammation from a controlled inflammatory response, for which steroids are not recommended.  相似文献   
45.
A 42-year-old man with a history of surgery for tongue cancer was referred to our hospital due to an abnormal chest shadow. High-resolution computed tomography showed lower lobe reticulation. A physical examination revealed nail dystrophy, oral leukoplakia, and reticulated hypopigmentation. Lung biopsy revealed subpleural and perilobular fibrosis, suggestive of usual interstitial pneumonia. However, multiple pathological findings, including homogenous fibrosis and cell infiltration in the centrilobular region, which were compatible with nonspecific interstitial pneumonia, and bronchiolitis were also seen. Genetic testing showed a hemizygous missense mutation in the DKC1 gene, and the patient was diagnosed with dyskeratosis congenita. Although anti-fibrotic therapy was initiated, the patient''s respiratory function has continued to decrease.  相似文献   
46.
A 40-year-old Japanese woman developed malignant-phase hypertension complicated by thrombotic microangiopathy, progressing to end-stage renal disease. Five years later, she was diagnosed with pulmonary arterial hypertension and interstitial pneumonia. Despite a lack of overt skin sclerosis, nucleolar staining in our indirect immunofluorescence analysis and nailfold capillaroscopy facilitated the diagnosis of anti-PM/Scl antibody-positive systemic sclerosis. We observed the persistent presence of anti-PM/Scl antibodies throughout the clinical course, suggesting that her kidney disease was scleroderma renal crisis. Anti-PM/Scl antibodies can be associated with multiple organ diseases. Careful attention to a patient''s antinuclear antibody pattern and dermatological findings may help clarify the etiology of undiagnosed diseases.  相似文献   
47.
Journal of Gastroenterology - Predictive factors for intrahepatic cholangiocarcinoma in long-term follow-up of hepatolithiasis are unknown. We thus conducted a cohort study to investigate the...  相似文献   
48.
Tocilizumab (TCZ), a biologic that blocks the signal transduction of interleukin-6, has been used for the treatment of various autoimmune diseases. Many of these cases are sometimes complicated by ulcerative colitis (UC). However, the effect of TCZ on UC is unclear. We experienced two cases with concomitant UC that were treated with TCZ, one for Takayasu arteritis (TAK) and the other for relapsing polychondritis (RP). TCZ did not improve UC in either of these cases. TCZ might have adverse effects on the intestinal tract, since interleukin-6 signaling plays an important role in intestinal epithelium maintenance. Treatment with TCZ should therefore be carefully provided in patients complicated with UC.  相似文献   
49.
Hyodo  Ryota  Takehara  Yasuo  Naganawa  Shinji 《La Radiologia medica》2022,127(11):1181-1198
La radiologia medica - Thus far, ultrasound, CT, and 2D cine phase-contrast MRI has been adopted to evaluate blood flow and vascular morphology in the portal venous system; however, all these...  相似文献   
50.
We report an acute myocardial infarction in a patient with a single coronary artery. The right coronary artery arose from the middle portion in the left anterior descending artery through the transverse branch. This type of single coronary artery has not been previously reported. Moreover, this is the first report in which the culprit lesion in a patient with a single coronary artery was observed by intravascular ultrasound and coronary angioscopy. The patient underwent successful coronary stent deployment.  相似文献   
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