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61.
62.
Simian Zhu Stella Corsetti Qifan Wang Chunhui Li Zhihong Huang Ghulam Nabi 《Journal of biophotonics》2019,12(10)
Non‐invasive detection of urinary bladder cancer remains a significant challenge. Urinary volatile organic compounds (VOCs) are a promising alternative to cell‐based biomarkers. Herein, we demonstrate a novel diagnosis system based on an optic fluorescence sensor array for detecting urinary bladder cancer VOCs biomarkers. This study describes a fluorescence‐based VOCs sensor array detecting system in detail. The choice of VOCs for the initial part was based on an extensive systematic search of the literature and then followed up using urinary samples from patients with urinary bladder transitional cell carcinoma. Canonical discriminant analysis and partial least squares discriminant analysis (PLS‐DA) were employed and correctly detected 31/48 urinary bladder cancer VOC biomarkers and achieved an overall 77.75% sensitivity and 93.25% specificity by PLS‐DA modelling. All five urine samples from bladder cancer patients, and five healthy controls were successfully identified with the same sensor arrays. Overall, the experiments in this study describe a real‐time platform for non‐invasive bladder cancer diagnosis using fluorescence‐based gas‐sensor arrays. Pure VOCs and urine samples from the patients proved such a system to be promising; however, further research is required using a larger population sample. 相似文献
63.
Iris M Markusse Jeska K de Vries-Bouwstra K Huub Han Peter AHM van der Lubbe Anne A Schouffoer Pit JSM Kerstens Willem F Lems Tom WJ Huizinga Cornelia F Allaart 《Arthritis research & therapy》2014,16(5)
Introduction
Personalized medicine is the holy grail of medicine. The EULAR recommendations for the management of rheumatoid arthritis (RA) support differential treatment between patients with baseline characteristics suggestive of a non-poor prognosis (non-PP) or poor prognosis (PP) (presence of autoantibodies, a high inflammatory activity and damage on radiographs). We aimed to determine which prognostic risk groups benefit more from initial monotherapy or initial combination therapy.Methods
508 patients were randomized to initial monotherapy (iMono) or initial combination therapy (iCombo). Disease outcomes of iMono and iCombo were compared within non-PP or PP groups as determined on baseline characteristicsResults
PP patients treated with iCombo after three months more often achieved ACR20 (70% vs 38%, P <0.001), ACR50 (48% vs 13%, P <0.001) and ACR70 response (24% vs 4%, P <0.001) than those treated with iMono, and had more improvement in HAQ (median decrease 0.75 vs 0.38, P <0.001). After 1 year, differences in ACR20 response and DAS-remission remained; PP patients treated with iCombo (vs iMono) had less radiographic progression (median 0.0 vs 1.5, P =0.001).Non-PP patients treated with iCombo after three months more often achieved an ACR response (ACR20: 71% versus 44%, P <0.001; ACR50: 49% vs 13%, P <0.001; ACR70: 17% vs 3%, P =0.001) than with iMono, and functional ability showed greater improvement (median decrease in HAQ 0.63 vs 0.38, P <0.001). After 1 year, differences in ACR20 and ACR50 response remained; radiographic progression was comparable between the groups.Non-PP and PP patients responded equally well to iCombo in terms of improvement of functional ability, with similar toxicity.Conclusions
Since PP and non-PP patients benefit equally from iCombo through earlier clinical response and functional improvement than with iMono, we conclude that personalized medicine as suggested in the guidelines is not yet feasible. The choice of treatment strategy should depend more on rapid relief of symptoms than on prognostic factors.Trial registration
Netherlands Trial Register NTR262 (registered 7 September 2005) and NTR265 (8 September 2005).Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0430-3) contains supplementary material, which is available to authorized users. 相似文献64.
65.
A two‐channel flow‐injection (FI) method is reported for the determination of iodide and iodine by its enhancement effect on the Ru(bpy)33+–NADH chemiluminescence (CL) system. The limit of detection (3 s of blank) was 1.0 × 10–9 mol/L iodide/iodine, with a sample throughput of 60/h. The calibration graphs over the range 1.0–50 × 10–8 mol/L gave correlation coefficients of 0.9994 and 0.999 (n = 5) with relative standard deviations (RSD; n = 4) of 1.0–2.5%, respectively. The effects of interfering cations, anions and some organic compounds were also studied. The method was applied to iodized salts and pharmaceutical samples and the results obtained were in good agreement with the value quoted. The CL method developed was compared with spectrophotometric method. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
66.
Characterization of milk composition in narrow‐ridged finless porpoises (Neophocaena asiaeorientalis) at different lactation stages
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Xianyuan Zeng Shiang‐lin Huang Zhengyi Qian Yujiang Hao Ding Wang Junhua Ji Ghulam Nabi 《Marine Mammal Science》2017,33(3):803-816
Lactation plays a vital role in reproductive success, evolving with ecological adaptations of mammalian life histories. Knowledge of the lactation process in odontocetes is scarce and limited to a handful of species. We investigated the changes in milk composition across different lactation stages, including prepartum mammary secretion and early, mid‐ and late lactation of narrow‐ridged finless porpoises. Prepartum mammary secretion was greenish and characterized by high protein, low sugar, and negligible fat contents. In contrast, milk fat became predominant over protein and sugar contents throughout all lactation stages. At the early lactation stage, the contents of all milk constituents except water varied greatly. At the mid‐late lactation stage, the gross milk composition was relatively stable and was composed of, on average, 67.34% ± 4.13% water, 9.96% ± 0.75% protein, 21.40% ± 3.24% fat, and 1.72% ± 0.73% sugar. Our findings provide new insight into milk composition at different lactation stages in the narrow‐ridged finless porpoise. 相似文献
67.
De novo reference intervals (RIs) for a total of thirty two hematological and serum biochemical attributes were established for rainbow trout (Oncorhynchus mykiss) cultured in Himalayan aquaculture system. For this purpose, long term assessment of hemato-biochemical parameters was carried over a period of one year from March 2019 to February 2020 and a total of 444 blood samples were analysed. Blood examination results were recorded systematically and reference intervals were established, notably for erythrocyte parameters: hematocrit (Hct) 29–40%, hemoglobin 8.32–12.28 g/dL, red blood cell (RBC) count 1.01–2.04 (×106/mm3); leukocyte parameters (x 103/mm3): total leukocytes 31.32–90.60, neutrophils 4.21–18.85, total lymphocytes 20.55–63.63, small lymphocytes 14.86–46.50, large lymphocytes 6.35–22.34 and monocytes 1.22–7.56; thrombocyte count 23.00–68.00 (×106/mm3). RIs were also established for red blood cell indices, vital serum constituents involved in carbohydrate, protein, lipid and nitrogen metabolism including the less known, diagnostically important, serum enzymes and electrolyte concentrations. Principal component analysis revealed that certain serum components were more efficient at distinguishing between the life stages (juvenile, adult) of fish by explaining about 92.7% of variation in the whole dataset compared to the principal hematological components which explained only about 80% of the variation. Significant (P < 0.05) differences were noted for RBC count, total leukocyte count (TLC), total protein, total cholesterol and uric acid with respect to the sex of fish. Moreover, clearly differentiable morphometric and morphological attributes were also noticed among erythrocytes, leukocytes (lymphocytes, neutrophils and monocytes) and thrombocytes. To our knowledge, the present study is the first of its kind that elucidates blood chemistry of cultured rainbow trout, O. mykiss in accordance to the guidelines framed by the American society of veterinary clinical pathologists (ASVCP). RIs reported here can help monitor the fish health status by improving the use of non-lethal diagnostics in piscine medicine. 相似文献
68.
明确物种生境空间分布格局及其与环境因素的关系,对了解该物种的生境需求和适宜生境空间分布至关重要。生境评价和预测是对物种进行有效保护的基础。以鹅喉羚(Gazella subgutturosa)为研究对象,以其重要栖息地新疆博州艾比湖国家级湿地自然保护区为研究区域,选取115个鹅喉羚分布点数据和23个环境变量因子,应用MAXENT模型分析其生境空间分布及主要影响因子,划分了鹅喉羚在研究区域的适宜生境,并对它的栖息地特征进行了分析。探讨了鹅猴羚生境选择与环境因子的关系。结果表明:气温日较差是影响鹅喉羚生境分布的主要环境因子。植被类型,坡度和最干月降水量对艾比湖鹅喉羚的生境选择影响不大。除了温度和降水在内的19项生物气候变量是鹅猴羚选择生境的重要因素之外,海拔和坡向等地形特征也影响鹅猴羚的生境选择性。鹅喉羚的高度适宜生境区主要分布在研究区域的北部和东部,中度及低度适宜生境区则分布于高度适宜生境区的边缘,而非适宜生境区主要集中在西部地区。研究不仅提供了鹅喉羚在艾比湖的实际分布状况及其栖息地特征,也为鹅喉羚在栖息地方面的研究,即鹅猴羚的栖息地选择和环境因子的关系方面提供了一个重要的依据。 相似文献
69.
Md. Abdullah Saeed Khan Mohammad Jahid Hasan Md. Utba Rashid Soumik Kha Sagar Sanzida Khan Susmita Zaman Sultan Mahamud Sumon Ariful Basher Mohammad Delwer Hossain Hawlader Mohammad Hayatun Nabi Nadira Sultana Kakoly 《PLoS neglected tropical diseases》2022,16(3)
BackgroundTetanus, a vaccine-preventable disease, is still occurring in the elderly population of low- and middle-income countries with a high case-fatality rate. The objective of the study was to elucidate the factors associated with in-hospital mortality of tetanus in Bangladesh.MethodsThis prospective observational study, conducted in two specialized infectious disease hospitals, conveniently selected adult tetanus patients (≥18 years) for inclusion. Data were collected through a preformed structured questionnaire. Kaplan Meier survival analysis and univariate and multivariable Cox regression analysis were carried out to assess factors associated with in-hospital mortality among patients. All analysis was done using Stata (version 16) and SPSS (version 26).ResultsA total of 61 tetanus cases were included, and the overall in-hospital mortality rate was 34.4% (n = 21). Patients had an average age of 46.49 ±15.65 years (SD), and the majority were male (96.7%), farmers (57.4%), and came from rural areas (93.4%). Survival analysis revealed that the probability of death was significantly higher among patients having an age of ≥ 40 years, incubation time of ≤12 days, onset time of ≤ 4 days, and having complication(s). However, on multivariable Cox regression analysis, age (adjusted hazard ratio [aHR] 4.03, 95% Confidence Interval [CI] 1.07–15.17, p = 0.039) and onset time (≤4 days) (aHR 3.33; 95% CI 1.05–10.57, p = 0.041) came as significant predictors of in-hospital mortality after adjusting for incubation period and complications.ConclusionOlder age and short onset time are the two most important determinants of in-hospital mortality of tetanus patients. Hence, these patients require enhanced emphasis and care. 相似文献
70.
Determination of manganese‐ and manganese‐containing fungicides with lucigenin–Tween‐20‐enhanced chemiluminescence detection
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A flow‐injection (FI) method is reported for the determination of Mn(II), maneb and mancozeb fungicides based on the catalytic effect of Mn(II) on the oxidation of lucigenin and dissolved oxygen in a basic solution. The Tween‐20 surfactant has been reported for first time to enhance lucigenin chemiluminescence (CL) intensity in the presence of Mn(II) (53%) and maneb and mancozeb (89%). The calibration graphs were linear in the concentration range of 0.001–1.5 mg L–1 (R2 = 0.9982 (n = 11) with a limit of detection (S/N = 3) of 0.1 µg L–1 for Mn(II) and 0.01–3.0 mg L–1 [R2 = 0.9989 and R2 = 0.9992 (n = 6)] with a limit of detection (S/N =3) of 1.0 µg L–1 for maneb and mancozeb respectively. Injection throughputs of 90 and 120 h–1 for Mn(II) and maneb and mancozeb respectively, and relative standard deviations of 1.0–3.4% were obtained in the concentration range studied. The experimental variables, e.g., reagents concentrations, flow rates, sample volume, and photomultiplier tube voltage, were optimized and potential interferences were investigated. The analysis of Mn(II) in river water reference materials (SLRS‐4 and SLRS‐5) showed good agreement with the certified values incorporating an on‐line 8‐hydroxyquinoline chelating column in the manifold for removing interfering metal ions. Recoveries for maneb and mancozeb were in the range of 92 ± 5 to 104 ± 3% and 91 ± 2 to 100 ± 4% (n = 3) respectively. The effect of 30 other pesticides (fungicides, herbicides and insecticides) was also examined in the lucigenin–Tween‐20 CL system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献