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51.
European Archives of Oto-Rhino-Laryngology - Stress has been suspected to play a role in rhinitis. The role of stress on nasal patency has been not yet elucidated. The aim was to evaluate the...  相似文献   
52.
Glasses in the TeO2-ZnO-Y2O3 (TZY) ternary system are examined in the present work. The vitrification domain of the chosen oxide matrix is determined and differential scanning calorimetry as well as X-ray diffraction measurements are carried out. The material characterizations reveal that Y2O3 incorporation cannot exceed 5 mol.% without causing detrimental crystallization within the glass. Optical transmission and refractive index investigations are conducted on compositions yielding fully amorphous samples. Next, the fiber drawing ability of selected yttrium-containing zinc-tellurite glasses is assessed and fiber-attenuation measurements in the mid-infrared are presented. Finally, a multimode step-index fiber is fabricated by combining a TZY cladding glass with a La2O3-based tellurite core glass. It is believed that yttrium-containing glasses could prove useful in association with other high glass transition temperature (>300 °C) TeO2-based materials for the design of robust optical fibers with precisely engineered refractive index profiles.  相似文献   
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Background

Fluoropyrimidine drugs are widely used in head and neck cancer (HNC). DPD deficiency is a pharmacogenetics syndrome associated with severe/lethal toxicities upon 5-FU or capecitabine intake. We have developed a simple, rapid, and inexpensive functional testing for DPD activity, as a means to identify deficient patients and to anticipate subsequent 5-FU-related toxicities. We present here the impact of fluoropyrimidine dose tailoring based on DPD functional screening in a prospective, open, non-controlled study, both in term of reduction in severe toxicities and of treatment efficacy.

Methods

About 65 patients with HNC (59?±?9?years, 52M/13F, Prospective Group) were entered into the study. Screening for DPD deficiency was performed prior to the beginning of the chemotherapy or radiochemotherapy. DPD status was evaluated by monitoring U/UH2 ratio levels in plasma as a surrogate marker for enzymatic functionality. 5-FU doses were reduced according to the extent of the detected DPD impairment, and adjusted on the basis of age, general condition, and other clinical/paraclinical covariates, if required. Treatment-related toxicities and subsequent impact on treatment delay were carefully monitored next for comparison with a retrospective, Reference subset of 74 other patients with HNC (mean age: 59?±?10, 58M/16F, Reference Group), previously treated in the same institute with similar schedule but using standard 5-FU dosage.

Results

Thirty-one out of 65 patients (48%) were identified as mildly (28%) to markedly (20%) DPD deficient. Subsequently, dose reductions ranging from 10 to 100% with 5-FU were applied in those patients. In this group, six patients (9%) experienced severe toxicities, none of them being life threatening, and no toxic death was encountered. In comparison, 16 out of 74 patients (22%) of the Reference Group displayed severe side effects after standard 5-FU administration, 13% being life-threatening toxicities (e.g., G4 neutropenia?+?sepsis). Moreover, one toxic death was observed in this Reference Group. No postponement or cancelation of forthcoming chemoradiotherapy courses occurred in the Prospective Group, whereas treatment had to be disrupted in six patients (8%) from the Reference Group. No difference in first-line therapy efficacy was evidenced between the two subsets (78 vs. 79% response, P?=?0.790).

Conclusions

Although non-randomized, this study strongly suggests that prospective determination of DPD status has an immediate clinical benefit by reducing the drug-induced toxicities incidence in patients treated with 5-FU, allowing an optimal administration of several courses in a row, while maintaining efficacy. Our preliminary results thus advocate for systematic DPD screening in patients eligible for treatment with fluoropyrimidine drugs in HNC.  相似文献   
57.
RotaTeq is an oral pentavalent rotavirus vaccine (RV5) that has shown high and consistent efficacy in preventing rotavirus gastroenteritis (RGE) in randomized clinical trials conducted mostly in industrialized countries. We projected the effectiveness of RV5 against RGE-related hospitalizations and deaths in 6 Asian countries by using a simple mathematical model. Model inputs included rotavirus surveillance data collected 2006-2007 in China, 2001-2002 in Hong Kong, 2005-2007 in India, 2005-2007 in South Korea, 2005-2007 in Taiwan, and 2001-2003 in Thailand; the numbers of rotavirus-related deaths in each country; and published rotavirus serotype-specific efficacy of RV5. The model projected an overall effectiveness in the region of 82% to 89% against RGE-related hospitalizations and a substantial reduction in RGE-related deaths, suggesting that RV5 could substantially reduce the burden of rotavirus disease in Asia.  相似文献   
58.
BackgroundRecurrence and distant metastases remain a significant issue in locally advanced rectal cancer (LARC). Several multimodal strategies are assessed in clinical trials.Patients and MethodsPatients with mid/low magnetic resonance imaging–defined high-risk LARC were randomized to arm A (12-week bevacizumab + FOLFOX-4 then bevacizumab–5-fluorouracil [5-FU]–radiotherapy [RT] before total mesorectal excision [TME]) or arm B (bevacizumab-5-FU–RT then TME). Long-term efficacy and safety up to 5 years’ follow-up are reported. No comparison between arms was planned.ResultsOverall, 91 patients (46 in arm A and 45 in arm B) were included. Main results have been presented previously. During the late follow-up period (> 4 weeks after surgery), 4 patients (8.7%) in arm A and 4 (8.9%) in arm B experienced grade 3/4 adverse events related to bevacizumab; the most frequent were 2 anastomotic fistulas (both in arm A) and abscesses (1 in arm A and 2 in arm B). At 5 years’ follow-up, 9 (19.6%) and 11 (24.4%) patients in arms A and B developed a fistula in the year after surgery, and 2 (4.3%) in arm A at > 1 year after surgery. Most resolved before study end. Five-year disease-free survival was 70% and 64.3% in arms A and B, respectively. Five-year overall survival was 90.5% (95% confidence interval, 76.7, 96.3) in arm A and 72.7% (95% confidence interval, 56.0, 83.9) in arm B.ConclusionNeoadjuvant bevacizumab + FOLFOX-4 may have the potential to increase survival outcomes when followed by bevacizumab–5-FU–RT and TME in LARC. Bevacizumab–5-FU–RT then TME was associated with a higher-than-projected rate of anastomotic fistulas. Further research of neoadjuvant strategies in LARC is encouraged.  相似文献   
59.
Continuous growth of mean tumor diameter in a subset of grade II gliomas   总被引:6,自引:0,他引:6  
Serial magnetic resonance images of 27 patients with untreated World Health Organization grade II oligodendrogliomas or mixed gliomas were reviewed retrospectively to study the kinetics of tumor growth before anaplastic transformation. Analysis of the mean tumor diameters over time showed constant growth. Linear regression, using a mixed model, found an average slope of 4.1mm per year (95% confidence interval, 3.8-4.4mm/year). Untreated low-grade oligodendrogliomas or mixed gliomas grow continuously during their premalignant phase, and their pattern of growth can be predicted within a relatively narrow range. These findings could be of interest to optimize patients management and follow-up.  相似文献   
60.
Exifone is a novel compound proposed for treating cognitive decline associated with age and shows corrective effects in animal models of memory dysfunction. The present experiments examined the antagonism by exifone of the amnesias induced in mice in a passive avoidance test by four benzodiazepines: bromazepam, diazepam, lorazepam and triazolam. Subsequent experiments investigated the specificity of exifone's antagonism of benzodiazepine-induced amnesia by examining its interaction with the effects of the benzodiazepines in the staircase test (anxiolytic/sedative activity) and the electroshock test (anticonvulsant activity). The results indicated that exifone clearly antagonised the amnesias induced by the four benzodiazepines, but was without intrinsic effects in the staircase or electroshock test and did not antagonise the effects of the benzodiazepines in these two tests. These results suggest that exifone might be useful for decreasing the amnesias induced by commonly used benzodiazepines without affecting their anxiolytic or anticonvulsant activity.Adlonec: marketed by Laboratoires Pharmascience, F-92400 Courbevoie, France  相似文献   
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