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91.
Microwave hyperthermia applicators are generally characterized at two or three frequencies. These frequencies usually are at the extremes of the applicator's operating range. However, such applicators are often used at arbitrary frequencies within their range. The most common reason for choice of frequency is to achieve acceptable coupling in the clinical configuration with a given patient. Occasionally a spurious transmission pattern will result from the frequency chosen that can lead to undetected high power densities well away from the target volume. In the present report, such a situation is discussed. The transmission pattern resembled "horns" reported at the field edge of certain accelerators. This pattern resulted in the inability to heat the target volume and the production of thermal blisters outside that volume. Such an occurrence underscores the need to characterize the transmission characteristics of a microwave hyperthermia applicator at all the frequencies used.  相似文献   
92.
BACKGROUND: Peripheral blood stem cell (PBSC) reinfusion has been widely used for hematopoietic reconstitution after high-dose chemotherapy. However, the optimal dose of granulocyte colony-stimulating factor (G-CSF) for PBSC mobilization in combination with chemotherapy for autograft remains unknown. METHODS: To find the optimal dose of glycosylated G-CSF (lenograstim) for PBSC mobilization in combination with chemotherapy for aggressive non-Hodgkin's lymphoma (NHL), we conducted a dose-finding study on 43 newly diagnosed patients who had unfavorable prognostic factors. They received four to six courses of cyclophosphamide, doxorubicin, vincristine and prednisolone combined with lenograstim every 2 weeks (biweekly CHOP therapy). PBSC apheresis was started after the third course of biweekly CHOP therapy. Lenograstim was given daily from day 3 until the day of the last apheresis. The optimum dose of lenograstim was assessed based on mobilization efficacy and safety profiles at a daily single dose of 2, 5 and 10 microg/kg for eight patients in each level. RESULTS: The collected number of CD34+ cells in the first apheresis products was higher in the 5 microg/kg group than in the 2 microg/kg group (median, 4.22 x 10(6) vs 2.49 x 10(6) CD34+ cells/kg, P = 0.051). The highest dose of 10 microg/kg (median, 2.99 x 10(6) CD34+ cells/kg) failed to show a dose dependence in PBSC mobilization. The efficacy and safety of the 5 microg/kg dose were further confirmed in an additional 19 patients. CONCLUSIONS: The present study suggests that the recommended dose of lenograstim for PBSC mobilization with CHOP therapy in untreated NHL is 5 microg/kg.  相似文献   
93.
Background: The outcomes for patients with NASH-related HCC after curative resection have not been clarified. This study compared the overall survival (OS), time-to-tumor recurrence (TTR), and recurrence-free survival (RFS) associated with NASH-related HCC and virus-related HCC after resection. Methods: Patients with HCC who underwent curative resection were retrospectively enrolled. Baseline characteristics, including disease etiologies and clinical and tumor features, were reviewed. The primary outcomes were OS, TTR, and RFS. Results: Two hundred and six patients were enrolled (HBV: n = 121, HCV: n = 54, NASH: n = 31). Of those with virus-related HCC, 84.0% achieved viral suppression. In both the overall and propensity-score-matched cohorts, those with NASH-related HCC experienced recurrence significantly earlier than those with virus-related HCC (median TTR: 1108 days vs. non-reached; p = 0.03). Through multivariate analysis, NASH-related HCC (hazard ratio (HR), 2.27; 95% confidence interval (CI), 1.25–4.12) was independently associated with early recurrence. The unadjusted RFS rate of the NASH-related HCC group was lower than the virus-related HCC group. There was no difference in the OS between the two groups. Conclusions: NASH-related HCC was associated with earlier tumor recurrence following curative resection compared to virus-related HCC. Post-surgical surveillance is crucial for detecting early recurrence in patients with NASH-related HCC.  相似文献   
94.
95.
To investigate the association of blood pressure and hypertension with disease severity among the patients with ankyloing spondylitis (AS). There were 167 AS patients enrolled in the cross-sectional study. Blood pressure was measured and the presence of hypertension was recorded. Patient’s disease severity, including disease activity, functional ability, patient’s global assessments, physical mobility and radiographic damage were evaluated. ESR and CRP levels were tested. We recorded patient’s medication use of NSAIDs, DMARDs and TNF-α blockers. Smoking, exercise habit, diabetes mellitus, hypercholesterolemia and obesity indices were assessed. Multivariate linear regression showed that systolic blood pressure was associated with TNF-α blocker [standard coefficient (β) = 0.194, P = .007], DMARDs (β = 0.142, P = .046), age (β = 0.211, P = .003), male gender (β = 0.242, P = .001) and body mass index (BMI) (β = 0.245, P = .001). Diastolic blood pressure was associated with cervical rotation (β = −0.174, P = .037), lateral lumbar flexion (β = −0.178, P = .019), m-SASSS (β = 0.198, P = .038) and BMI (β = 0.248, P = .003). Notably, multivariate logistic regression showed that hypertension was associated with m-SASSS (OR = 1.033, P = .033), age (OR = 1.098, P = .0010) and BMI (OR = 1.210, P = .003). Using ROC cure analyses, age, BASMI, BASRI-Total, m-SASSS, waist circumference, BMI and waist-to-height ratio were useful in predicting hypertension, and m-SASSS is the best (AUC = 0.784, P < .001). Advanced radiographic damage is an independent risk factor of hypertension in AS, and m-SASSS is the most useful disease severity parameter in predicting the presence of hypertension. Advanced radiographic damage, poor cervical rotation, lateral lumbar flexion, older age, male gender, TNF-α blocker, DMARDs use and obesity are associated with increased blood pressure.  相似文献   
96.
97.
The coronavirus disease 2019 (COVID-19) pandemic has caused a heavily burden on healthcare workers (HCWs) worldwide. The aim of this study was to compare differences in psychological and social impact between two waves of the pandemic among first- and second-line HCWs in Taiwan. The current study derived data from two cross-sectional surveys conducted in 2020 and 2021. Levels of depression, sleep disturbance, psychological distress, social impact, and demographic variables were collected through self-reported questionnaires. The independent t test was used to compare differences in scores between the first and second wave of the pandemic. Differences between first- and second-line HCWs were also analyzed. A total of 711 HCWs in the first wave and 560 HCWs in the second wave were recruited. For the first- and second-line HCWs, the social impact during the second wave was higher than during the first wave, and they expressed a higher intention to maintain social distancing and were more aware of the pandemic overseas in the second wave. The first-line HCWs had a trend of worse sleep quality during the second wave. In addition, sleep quality was worse in the first-line HCWs than in the second-line HCWs during both waves. The second-line HCWs expressed a greater desire to seek COVID-19-related information than the first-line HCWs during the first wave, and more intended to maintain social distancing during the second wave. Our results show the importance of evaluating the social and mental health burden of HCWs, and especially first-line workers.  相似文献   
98.
99.
Five new cucurbitane-type triterpenes, (23E)-25-methoxycucurbit-23-ene-3beta,7beta-diol (1), (23E)-cucurbita-5,23,25-triene-3beta,7beta-diol (2), (23E)-25-hydroxycucurbita-5,23-diene-3,7-dione (3), (23E)-cucurbita-5,23,25-triene-3,7-dione (4), and (23E)-5beta,19-epoxycucurbita-6,23-diene-3beta,25-diol (5), together with one known triterpene, (23E)-5beta,19-epoxy-25-methoxycucurbita-6,23-dien-3beta-ol (6), have been isolated from the methanol extract of the stems of Momordica charantia. The structures of the new compounds were elucidated by spectroscopic methods.  相似文献   
100.
目的 探讨改良Ⅱ期法耳廓再造的方法并总结6年来的临床应用经验。方法 对146例(155耳)小耳畸形患者行耳廓再造术,手术分Ⅱ期进行。Ⅰ期:采用“U”形切口,切除残耳,在耳后分离合适的腔隙,置入肋软骨耳支架,耳垂向后转位衔接于再造的耳廓下方。6个月后行Ⅱ期手术:掀起耳廓,耳后置入软骨块,颞浅筋膜瓣转移覆盖后行中厚皮片移植术。结果 146例患者中141例(150耳)Ⅰ期术后恢复顺利,伤口愈合良好;5例(5耳)Ⅰ期术后4~6d出现皮瓣尖端坏死,范围约1.0 cm×1.5 cm,经换药后痊愈,未出现软骨外露、感染等;139例(147耳)Ⅱ期术后耳后移植皮片成活良好,7例(8耳)Ⅱ期术后出现耳后移植皮片部分成活不良,换药1周后愈合。146例患者随访94例(97耳),失访52例(58耳),随访时间为术后6个月至2年,随访病例均无感染、软骨吸收等并发症,再造耳廓结构清晰,耳颅角稳定。结论 改良Ⅱ期法耳廓再造手术操作相对简单,易于掌握,是耳廓再造的较为理想的方法之一。  相似文献   
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