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81.

Background  

Although modest improvements in the survival of patients with non-small cell lung cancer (NSCLC) can be achieved with cisplatin-based chemotherapy (CT), its value is disputed in the geriatric setting. In this study, we evaluate the feasibility of vinorelbine/cisplatin CT for elderly NSCLC patients.  相似文献   
82.
This study aimed to evaluate and compare the effects of ambient temperature and post-manufacture heat-treatment on the mechanical behavior of nickel-titanium (NiTi) wires. Four types of commercial NiTi variants (Stock NiTi, heat treated “Blue”, “Gold”, “Superflex”, all Dentsply Maillefer, Ballaigues, Switzerland) were stressed in a tensile testing machine in a temperature-controlled water bath at three different temperatures. Stress and strain values were extrapolated from the raw data, and 2-way ANOVA and Tukey’s test for multiple comparisons were performed to compare the differences of the mechanical constants. Differential scanning calorimetry (DSC) tests established the martensitic transformation starting (Ms), finishing (Mf) and austenitic (reverse-martensitic) starting (As) and finishing (Af) points. Austenitic modulus of elasticity and transformation stress values increased with temperature for all NiTi groups. The martensitic modulus of elasticity, maximum transformation strain and ultimate tensile stress were not significantly affected by temperature changes. Stock NiTi and Gold wire samples presented with clearly delineated austenitic and martensitic transformations in the DSC experiments. Differences in manufacturing/heat treatment conditions and ambient temperature affect the mechanical behavior of nickel-titanium and may have clinical implications. Further improvements to the experimental setup could be considered to provide more accurate measurements of strain.  相似文献   
83.
Plant-derived (poly)phenolic compounds have been undoubtedly shown to promote endocrine homeostasis through the improvement of diverse metabolic outcomes. Amongst diverse potential mechanisms, the prebiotic modulatory effects exerted by these compounds on the gut microbiota have supported their nutraceutical application in both experimental and clinical approaches. However, the comprehension of the microbiota modulatory patterns observed upon (poly)phenol-based dietary interventions is still in its infancy, which makes the standardization of the metabolic outcomes in response to a given (poly)phenol a herculean task. Thus, this narrative review sought to gather up-to-date information on the relationship among (poly)phenols intake, their modulatory effect on the gut microbiota diversity, and consequent metabolic outcomes as a supportive tool for the future design of experimental approaches and even clinical trials.  相似文献   
84.
A concise synthesis of molnupiravir in a one-pot two-step approach starting from uridine is described. Formally, herein, two sets of one-pot two-reaction steps introducing simplicity for purifications and using chemically available reagents are presented. In this context, molnupiravir was obtained in up to 68% overall yield and multigram-scale. In addition, HPLC analysis showed the molnupiravir purity above 99%.

Fast, effective and chromatography column-free chemical synthesis of molnupiravir.  相似文献   
85.
86.
Ophidian accidents caused by the subspecies Crotalus durissus are responsible for high morbity and mortality rates. Acute renal failure is a common complication observed in these accidents. The aim of the present study was to investigate the renal effects promoted by the venom of C. d. collilineatus and its fractions, crotoxin and phospholipase A2. C. d. collilineatus (Cdc; 30 microg mL(-1)), crotoxin (CTX; 10 microg mL(-1)) and phospholipase A2 (PLA2; 10 microg mL(-1)) were tested in isolated rat kidney. The first 30 min of each experiment were used as an internal control and Cdc or its fractions, CTX and PLA2 were added to the system after this period. All experiments lasted 120 min. The venom of Cdc decreased perfusion pressure (PP; control120 = 110.3 +/- 3.69 mmHg; Cdc120 = 96.7+/-8.1 mmHg), renal vascular resistance (RVR; control120 = 6.42+/-0.78 mmHg mL g(-1) min(-1); Cdc120 = 4.8+/-0.56 mmHg/mL g(-1) min(-1)), urinary flow (UF; control120 = 0.19+/-0.03 mL g(-1) min(-1); Cdc120 = 0.12 +/- 0.01 mL g(-1) min(-1)), and glomerular filtration rate (GFR; control120 = 0.79 +/- 0.07 mL g(-1) min(-1); Cdc120 = 0.53 +/- 0.09 mL g(-1) min(-1)), but had no effect on the percent of sodium tubular transport (%TNa+), percent of chloride tubular transport (%TK+) and percent of potassium tubular transport (%TCl-). CTX and PLA2 reduced the GFR, while UF, PP and RVR remained stable during the full 120 min of perfusion. Crotoxin administration also diminished the %TK+ (control120 = 69.94 +/- 6.49; CTX120 = 33.28 +/- 4.78) and %TCl- (control120 = 79.53 +/- 2.67; CTX120 = 64.62 +/- 6.93). PLA2 reduced the %TK+, but exerted no effect on the %TNa+ or on that of TCl-. In conclusion, the C. d. collilineatus venom altered the renal functional parameters evaluated. We suggest that crotoxin and phospholipase A2 were involved in this process, since the renal effects observed would be due to the synergistic action of the components of the venom.  相似文献   
87.
Longitudinal studies evaluating the relationship between UPF consumption and the incidence of Metabolic Syndrome (MetS) and its components are still scarce. This study aimed to evaluate the effect of UPF consumption on the incidence of MetS and its components in adults. A prospective study was conducted with 896 participants from the 1978/79 Ribeirão Preto cohort, São Paulo, Brazil. UPF consumption was evaluated in %kcal and %g at ages 23–25 years. Incidence of MetS and its components were estimated at ages 37–39 years, according to the Joint Interim Statement criteria. Poisson regression was used to assess associations, and interactions with sex were investigated. UPF consumption had no association with MetS (%kcal Adjusted PR: 1.00; 95% CI: 0.99–1.01; %g Adjusted PR: 1.00; 95% CI: 0.99–1.01). However, women with higher UPF consumption, in %kcal and %g, had a higher risk of abdominal obesity (%kcal: p = 0.030; %g: p = 0.003); and women with higher UPF consumption, in %g, had a higher risk of low HDL-cholesterol (p = 0.041). For the other components of MetS, no significant associations were observed in either sex. These findings suggest evidence of no association between UPF consumption and MetS; however, consumption of UPF was associated with increased WC and low HDL-c, but only in women.  相似文献   
88.
血、尿中安眠酮及其代谢物的测定   总被引:1,自引:0,他引:1  
刘锋  刘荫棠  冯翠玲  罗毅 《药学学报》1994,29(8):610-616
通过一例安眠酮中毒病人血、尿中安眠酮及其代谢物的测定,描述了用紫外光谱(uv)、气相色谱(GC)和气相色谱质谱(GC/MS)法测定安眠酮及其代谢物的系统分析方法。样品的提取净化采用液一液萃取和固相萃取两种方法,都得到了很好的结果。紫外光谱用于测定血、尿中安眠酮和其代谢物的总量;气相色谱用于测定血、尿中安眠酮原药的含量;气相色谱质谱则用于鉴定血、尿中的安眠酮及其代谢物。除安眠酮外,血、尿中共检出10种安眠酮代谢物,其中包括两种乙酰化代谢物。此法还为临床救治提供指导。  相似文献   
89.
90.
Patients with Inflammatory Bowel Disease (IBD) are at increased risk of psychological and physical burden, including sexual dysfunction (SD). This study aimed to assess the prevalence of SD and to identify its predictive factors, in IBD patients. This unicentric cross-sectional case-control survey (ratio 2:1) included patients followed at the day hospital IBD consultation, in the Gastroenterology department of a tertiary referral center, for 2 years. Participants received anonymous questionnaires, concerning basic characteristics and sexual function, and a questionnaire on anxiety and depression, body image, fatigue, and IBD-specific health-related quality of life (QoL). We analyzed data from 120 IBD patients and 60 healthy controls. Forty-two female (56.8%) and 6 male (14.6%) IBD patients, and 6 women (15%) and 2 males (10%) of the control group presented SD. SD was significantly higher in IBD patients with age between 18 and 30 and 51 and 60 than in healthy controls (P < .05) Regarding multivariate analysis, age was a predictive factor for SD in males (P = .014), and anxiety and depression (P = .002) and fatigue (P = .043) in females. SD is a predictor of lower QoL among IBD patients, considering the last 15 (P < .001) and 60 days (P = .001), regarding univariate analysis. SD (P = .007), body image distortion (P < .001), and fatigue (P = .004) were predictors of low QoL (last 15 days, multivariate analysis). SD was more prevalent in IBD patients than in the control group and impacted negatively the QoL of patients. Age was a predictive factor for SD in men while anxiety and depression, and fatigue were predictive of SD in women.  相似文献   
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