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Learning Discriminatory Information for Object Detection on Urine Sediment Image
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作者 Sixian Chan Binghui Wu +2 位作者 Guodao Zhang Yuan Yao Hongqiang Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期411-428,共18页
In clinical practice,the microscopic examination of urine sediment is considered an important in vitro examination with many broad applications.Measuring the amount of each type of urine sediment allows for screening,... In clinical practice,the microscopic examination of urine sediment is considered an important in vitro examination with many broad applications.Measuring the amount of each type of urine sediment allows for screening,diagnosis and evaluation of kidney and urinary tract disease,providing insight into the specific type and severity.However,manual urine sediment examination is labor-intensive,time-consuming,and subjective.Traditional machine learning based object detection methods require hand-crafted features for localization and classification,which have poor generalization capabilities and are difficult to quickly and accurately detect the number of urine sediments.Deep learning based object detection methods have the potential to address the challenges mentioned above,but these methods require access to large urine sediment image datasets.Unfortunately,only a limited number of publicly available urine sediment datasets are currently available.To alleviate the lack of urine sediment datasets in medical image analysis,we propose a new dataset named UriSed2K,which contains 2465 high-quality images annotated with expert guidance.Two main challenges are associated with our dataset:a large number of small objects and the occlusion between these small objects.Our manuscript focuses on applying deep learning object detection methods to the urine sediment dataset and addressing the challenges presented by this dataset.Specifically,our goal is to improve the accuracy and efficiency of the detection algorithm and,in doing so,provide medical professionals with an automatic detector that saves time and effort.We propose an improved lightweight one-stage object detection algorithm called Discriminatory-YOLO.The proposed algorithm comprises a local context attention module and a global background suppression module,which aid the detector in distinguishing urine sediment features in the image.The local context attention module captures context information beyond the object region,while the global background suppression module emphasizes objects in uninformative backgrounds.We comprehensively evaluate our method on the UriSed2K dataset,which includes seven categories of urine sediments,such as erythrocytes(red blood cells),leukocytes(white blood cells),epithelial cells,crystals,mycetes,broken erythrocytes,and broken leukocytes,achieving the best average precision(AP)of 95.3%while taking only 10 ms per image.The source code and dataset are available at https://github.com/binghuiwu98/discriminatoryyolov5. 展开更多
关键词 Object detection attention mechanism medical image urine sediment
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Simultaneous determination of fluorine and iodine in urine by ion chromatography with electrochemical pretreatment 被引量:4
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作者 Kang Kang Hu Wei Xiong Huang Yu Hua Su Rong Zong Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1483-1486,共4页
为在由有电气化学的预告的处理的离子层析(IC ) 的尿的氟的符号和碘的同时的决心的一个新方法被开发了。预告的处理在新奇电气化学的 oxidation&#x2013 被执行;中立化设备(EOND ) ,在哪个样品的碘化物被氧化到以碘处理和碱的消化... 为在由有电气化学的预告的处理的离子层析(IC ) 的尿的氟的符号和碘的同时的决心的一个新方法被开发了。预告的处理在新奇电气化学的 oxidation&#x2013 被执行;中立化设备(EOND ) ,在哪个样品的碘化物被氧化到以碘处理和碱的消化样品答案被抵销。在优化条件下面,察觉的限制(LOD, S/N = 3 ) 是 2.5 &#x3bc;为氟化物的 g/L 和 20 &#x3bc;为以碘处理的 g/L 分别地。恢复在 93 &#x2013 的范围; 102% 为氟化物和 86 &#x2013; 98% 为以碘处理。 展开更多
关键词 电化学预处理 离子色谱 同时测定 氟化物 尿碘 优化条件 检测限 回收率
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Research on Relationship Between Fluorine in Tap Water and That in Urine of Chinese Residents 被引量:2
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作者 王滨滨 郑宝山 +2 位作者 翟城 刘小静 安宁 《Chinese Journal Of Geochemistry》 EI CAS 2004年第4期373-379,共7页
In this study, the relationship between fluorine in drinking water and that in urine of urban residents in China is assessed. Fluorine concentrations in tap water and those in urine show a good correlation with a line... In this study, the relationship between fluorine in drinking water and that in urine of urban residents in China is assessed. Fluorine concentrations in tap water and those in urine show a good correlation with a linear regression coefficient of 0.9798, indicating that the fluorine concentrations in big cities under investigation are extremely low, and the main source of fluorine is tap water. The weather effect on the intake amount of fluorine is also discussed. When air temperature is above 15℃, people would intake more fluorine through drinking water with the rise of air temperature. When temperature is below 15℃, no remarkable relationship is observed between air temperature and the intake amount of fluorine. This phenomenon indicates that the main source of fluorine in China is tap water instead of foodstuff. 展开更多
关键词 自来水 尿液 口腔卫生 消毒净化
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Fluoridation routes,function mechanism and application of fluorinated/fluorine-doped nanocarbon-based materials for various batteries:A review
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作者 Weicui Liu Nanping Deng +5 位作者 Gang Wang Ruru Yu Xiaoxiao Wang Bowen Cheng Jingge Ju Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期363-393,I0011,共32页
With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms... With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms,doping fluorine atoms in nanocarbon-based materials is considered an effective way to improve the performance of used battery.However,there is still a blank in the systematic review of the mechanism and research progress of fluorine-doped nanostructured carbon materials in various batteries.In this review,the synthetic routes of fluorinated/fluorine-doped nanocarbon-based(CF_x)materials under different fluorine sources and the function mechanism of CF_x in various batteries are reviewed in detail.Subsequently,judging from the dependence between the structure and electrochemical performance of nanocarbon sources,the progress of CF_x based on different dimensions(0D–3D)for primary battery applications is reviewed and the balance between energy density and power density is critically discussed.In addition,the roles of CF_x materials in secondary batteries and their current applications in recent years are summarized in detail to illustrate the effect of introducing F atoms.Finally,we envisage the prospect of CF_x materials and offer some insights and recommendations to facilitate the further exploration of CF_x materials for various high-performance battery applications. 展开更多
关键词 Nanocarbon materials Fluorinated/fluorine-doped effect Function mechanism Various batteries
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Effects of Inhabiting and Life Patterns on the UV Spectral Properties of Small Mammalian Herbivores’ Urine
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作者 Junnian Li 《Open Journal of Forestry》 2023年第1期32-44,共13页
It is well known that avian predators can use prey excretions such as urine and feces to track their prey, and the urine and feces of small mammalian herbivores can reflect ultraviolet (UV) light and emit fluorescent ... It is well known that avian predators can use prey excretions such as urine and feces to track their prey, and the urine and feces of small mammalian herbivores can reflect ultraviolet (UV) light and emit fluorescent light. There are still some debates as to whether UV visibility of small mammalian herbivores’ urine is used as a hunting cue by avian raptors. Some studies in Europe have demonstrated that diurnal raptors are capable of utilizing these cues to target key prey species. However, researchers in Australia have argued that raptors do not use the UV visibility of urine while hunting. To our knowledge, there are no reports from Asia concerning the ultraviolet spectral characteristics of small mammal herbivores’ urine. This study examined the UV spectral properties of urine from 6 small mammal herbivores species by comparing the UV reflectance and fluorescence spectra of urine from small mammalian herbivores living in plateau meadows, plateau shrubs, open marshland, farmland, and semi-desert grassland in China. In addition, we compared the UV spectral properties of urine from ground-dwelling species of rodents and subterranean species to determine whether ultraviolet visibility of small mammal herbivores’ urine could be used as a visual signal by Asian vole-eating raptors. The results showed that: 1) the SC<sub>370</sub> values of urine from four small mammal herbivores species were ordered as plateau pika (plateau meadow) > root voles (plateau bush) > reed voles (swampland) > Brandt’s vole (desert grassland);and 2) UV fluorescence peak intensity and the wavelengths of urine from ground-dwelling species (such as the root vole, plateau pika, or Brandt’s vole) were significantly higher than those of subterranean-dwelling species (mandarin vole and plateau zokor). These results indicate that UV visibility of small mammal herbivores’ urine may act as a visual cue for raptors. 展开更多
关键词 Rodents urine Ultraviolet (UV) Light FLUORESCENCE
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Can the Urine Dipstick Test Be an Alternative in the Screening of Urinary Tract Infections for Inpatients in the Context of a Low-Income Country?
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作者 André Nagalo Odilon D. Kaboré +10 位作者 Senkaye-Lagom Aimée Kissou Hervé Kafando Boukary Kabré Emmanuel Zongo Cheick Ahmed Ouattara Yacouba Sawadogo Aoua Semdé Jacques Zoungrana Armel Poda Sylvain Godreuil Abdoul-Salam Ouédraogo 《Advances in Infectious Diseases》 2023年第4期627-640,共14页
Background: Urinary Tract Infection (UTI), a prevalent bacterial infection in adults, heavily relies on cytobacteriological examination of urine (CBEU) for diagnosis. However, in resource-limited countries, accessibil... Background: Urinary Tract Infection (UTI), a prevalent bacterial infection in adults, heavily relies on cytobacteriological examination of urine (CBEU) for diagnosis. However, in resource-limited countries, accessibility to CBEU remains hindered by cost and availability. This study aims to assess the utility of the Urinary Dipstick Test (UDT) in diagnosing UTIs among hospitalized patients in the context of limited resources. Methods: A cross-sectional study was conducted from February to May 2019, encompassing hospitalized patients who underwent CBEU at the bacteriology unit of Sour? Sanou University Hospital. UDT and CBEU were concurrently performed, and UDT’s analytical and diagnostic performance was evaluated against CBEU, considered the gold standard. Results: A total of 274 CBEU requests were registered, involving 274 patients (159 males) with a mean age of 45.8 ± 21.3 years (ranging from 1 to 90 years). UTI was confirmed in 90 patients, yielding a frequency of 32.85%. The UTI bacteriological profile was dominated by Enterobacteriaceae (75.23%), primarily Escherichia coli (60.55%). Nitrite and Leukocytes were positive in 54 (19.8%) and 157 (53.6%) of the samples tested. Among patients with confirmed UTI, Nitrite, and Leukocytes were positive in 30 (33%) and 71 (79%) patients respectively. UDT demonstrated variable performance based on nitrite and leukocyte combination: Sensitivity (57%-82%), Specificity (7%-98%), Positive Predictive Value (PPV) (43%-57%), Negative Predictive Value (NPV) (43%-67%). UDT performed slightly better in women (NPV = 88%) and inpatients without urinary catheters (NPV = 75% and PPV = 80%). Conclusion: This study underscores UDT’s potential utility in excluding UTIs among women, younger patients, and inpatients without urinary catheters, albeit with limited confidence. The UDT emerges as a complementary tool for UTI screening, particularly in resource-limited settings. 展开更多
关键词 urine Dipstick Test Urinary Tract Infection LMICs Burkina Faso
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Study on Distribution Characteristics and Occurrence Form of Soil Fluorine in Sorghum Base of Renhuai City
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作者 Ziping PAN Maoyan SHAO +2 位作者 Xubin HUANG Ting CHEN Luyao SUI 《Agricultural Biotechnology》 CAS 2023年第1期66-71,共6页
In order to find out the effects of soil fluorine on ecological environment and crop safety in the sorghum cultivation base of Renhuai City, Guizhou Province, the content and the occurrence forms of soil fluorine and ... In order to find out the effects of soil fluorine on ecological environment and crop safety in the sorghum cultivation base of Renhuai City, Guizhou Province, the content and the occurrence forms of soil fluorine and its influencing factors of Maoba Town were investigated and studied. The results showed that the total fluorine content in the soil of the sorghum base ranged from 668.60 to 2 596.80 mg/kg, with an average of 1 483.25 mg/kg, which was 3.10 and 1.85 times of the national soil background value and the average value of the soil in endemic areas, respectively. The spatial distribution of fluorine in the soil of the study area was uneven, and the fluorine content was in the order of Anliang Village>Yangliu Village>Houba Village>Xiongfeng Village. The soil fluorine contents of various forms varied greatly, and the distribution law was as follows: residual state>water soluble state>organically bound state>exchangeable state>Fe/Mn-F state. The residual fluorine content was the highest, accounting for more than 99% of total fluorine content, while the sum of other four forms was less than 1%, with their respective proportions ranging from 0.10% to 0.30%. The content and proportion of available fluorine in water-soluble and exchangeable states were relatively low, which had limited influence on the surrounding water environment and crop safety. The physicochemical properties of soil, such as pH, organic matter, cation exchange capacity and clay particles had a certain influence on the occurrence forms of soil fluorine, thus changing the availability and migration of soil fluorine, which might endanger the ecological environment safety, food safety and human health. 展开更多
关键词 Sorghum base Soil fluorine Occurrence form Distribution characteristics Renhuai City
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Diagnosis of an intermediate case of maple syrup urine disease:A case report
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作者 Yun-Ting Lin Yan-Na Cai +5 位作者 Tzer Hwu Ting Li Liu Chun-Hua Zeng Ling Su Min-Zhi Peng Xiu-Zhen Li 《World Journal of Clinical Cases》 SCIE 2023年第5期1077-1085,共9页
BACKGROUND Maple syrup urine disease(MSUD)is an autosomal recessive genetic disorder caused by defects in the catabolism of the branched-chain amino acids(BCAAs).However,the clinical and metabolic screening is limited... BACKGROUND Maple syrup urine disease(MSUD)is an autosomal recessive genetic disorder caused by defects in the catabolism of the branched-chain amino acids(BCAAs).However,the clinical and metabolic screening is limited in identifying all MSUD patients,especially those patients with mild phenotypes or are asymptomatic.This study aims to share the diagnostic experience of an intermediate MSUD case who was missed by metabolic profiling but identified by genetic analysis.CASE SUMMARY This study reports the diagnostic process of a boy with intermediate MSUD.The proband presented with psychomotor retardation and cerebral lesions on magnetic resonance imaging scans at 8 mo of age.Preliminary clinical and metabolic profiling did not support a specific disease.However,whole exome sequencing and subsequent Sanger sequencing at 1 year and 7 mo of age identified bi-allelic pathogenic variants of the BCKDHB gene,confirming the proband as having MSUD with non-classic mild phenotypes.His clinical and laboratory data were retrospectively analyzed.According to his disease course,he was classified into an intermediate form of MSUD.His management was then changed to BCAAs restriction and metabolic monitoring conforming to MSUD.In addition,genetic counseling and prenatal diagnosis were provided to his parents.CONCLUSION Our work provides diagnostic experience of an intermediate MSUD case,suggesting that a genetic analysis is important for ambiguous cases,and alerts clinicians to avoid missing patients with non-classic mild phenotypes of MSUD. 展开更多
关键词 Maple syrup urine disease BCKDHB gene Branched-chain amino acids Metabolic profiling Genetic analysis Case report
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Diagnostic value of matrix metalloproteinases 2, 7 and 9 in urine for early detection of colorectal cancer
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作者 Liu Peng Xin Zhang +2 位作者 Man-Li Zhang Tao Jiang Peng-Jun Zhang 《World Journal of Gastrointestinal Surgery》 2023年第5期931-939,共9页
BACKGROUND A noninvasive biomarker with high diagnostic performance is urgently needed for the early diagnosis of colorectal cancer(CRC).AIM To evaluate the diagnostic value of matrix metalloproteinases(MMPs)2,7 and 9... BACKGROUND A noninvasive biomarker with high diagnostic performance is urgently needed for the early diagnosis of colorectal cancer(CRC).AIM To evaluate the diagnostic value of matrix metalloproteinases(MMPs)2,7 and 9 in urine for CRC.METHODS Of 59 healthy controls,47 patients with colon polyps and 82 patients with CRC were included in this study.Carcinoembryonic antigen(CEA)in serum and MMP2,MMP7,and MMP9 in urine were detected.The combined diagnostic model of the indicators was established by binary logistic regression.The receiver operating characteristic curve(ROC)of the subjects was used to evaluate the independent and combined diagnostic value of the indicators.RESULTS The MMP2,MMP7,MMP9,and CEA levels in the CRC group differed significantly from levels in the healthy controls(P<0.05).The levels of MMP7,MMP9,and CEA also differed significantly between the CRC group and the colon polyps group(P<0.05).The area under the curve(AUC)distinguishing between the healthy control and the CRC patients using the joint model with CEA,MMP2,MMP7 and MMP9 was 0.977,and the sensitivity and specificity were 95.10%and 91.50%,respectively.For early-stage CRC,the AUC was 0.975,and the sensitivity and specificity were 94.30%and 98.30%,respectively.For advanced stage CRC,the AUC was 0.979,and the sensitivity and specificity were 95.70%and 91.50%,respectively.Using CEA,MMP7 and MMP9 to jointly established a model distinguishing the colorectal polyp group from the CRC group,the AUC was 0.849,and the sensitivity and specificity were 84.10%and 70.20%,respectively.For early-stage CRC,the AUC was 0.818,and the sensitivity and specificity were 76.30%and 72.30%,respectively.For advanced stage CRC,the AUC was 0.875,and the sensitivity and specificity were 81.80%and 72.30%,respectively.CONCLUSION MMP2,MMP7 and MMP 9 may exhibit diagnostic value for the early detection of CRC and may serve as auxiliary diagnostic markers for CRC. 展开更多
关键词 Colorectal cancer Early detection Matrix metalloproteinases urine BIOMARKER
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术前床上排尿训练联合集束化护理对心房颤动射频消融术患者卧位排尿功能的影响
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作者 魏小英 李嘉蔚 +2 位作者 陈群连 颜琼 殷然 《中国当代医药》 CAS 2024年第5期183-187,共5页
目的研究心房颤动(以下称“房颤”)患者在射频消融术治疗期间接受术前床上排尿训练联合集束化护理干预的临床效果。方法选取2021年7月至2022年8月南昌大学第一附属医院收治的64例房颤患者作为研究对象,采用随机数字表法将其分成对照组(3... 目的研究心房颤动(以下称“房颤”)患者在射频消融术治疗期间接受术前床上排尿训练联合集束化护理干预的临床效果。方法选取2021年7月至2022年8月南昌大学第一附属医院收治的64例房颤患者作为研究对象,采用随机数字表法将其分成对照组(32例)和观察组(32例)。对照组开展常规射频护理,观察组开展术前床上排尿训练联合集束化护理干预。比较两组的手术操作时间、术后首次排尿时间、导尿次数、术后12 h残余尿量、护理前后心理状态评分、治疗依从性、护理满意度、术后膀胱功能分级、尿潴留发生情况。结果观察组的手术操作时间、术后首次排尿时间短于对照组,差异有统计学意义(P<0.05)。观察组的导尿次数和术后12 h残余尿量少于对照组,差异有统计学意义(P<0.05)。观察组的住院时间短于对照组,差异有统计学意义(P<0.05)。护理前,两组患者的心理状态评分比较,差异无统计学意义(P>0.05);护理后,观察组的心理状态评分低于对照组,差异有统计学意义(P<0.05)。观察组的治疗依从性高于对照组,差异有统计学意义(P<0.05)。观察组的护理总满意度高于对照组,差异有统计学意义(P<0.05)。术后,观察组的膀胱功能分级优于对照组,差异有统计学意义(P<0.05)。观察组的尿潴留发生率低于对照组,差异有统计学意义(P<0.05)。结论房颤患者在射频消融术治疗期间接受术前床上排尿训练联合集束化护理干预,能够帮助改善膀胱功能,保持良好心态,缩短治疗操作时间和恢复时间,减少导尿次数,防止尿潴留的发生,使治疗依从性和满意度得到显著提升。 展开更多
关键词 心房颤动 射频消融术 术前床上排尿训练 集束化护理 排尿功能
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术前量化排尿训练联合术后盆底肌电刺激在前列腺癌根治术患者中的应用
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作者 徐静 宋思霖 许露伟 《中国医药导报》 CAS 2024年第3期175-178,共4页
目的 探讨术前量化排尿训练联合术后盆底肌电刺激对前列腺癌根治术患者的影响。方法 前瞻性纳入南京市第一医院2019年9月至2022年9月拟行前列腺癌根治术治疗的100例患者,以随机数字表法将其分为对照组与观察组,各50例。对照组接受术前... 目的 探讨术前量化排尿训练联合术后盆底肌电刺激对前列腺癌根治术患者的影响。方法 前瞻性纳入南京市第一医院2019年9月至2022年9月拟行前列腺癌根治术治疗的100例患者,以随机数字表法将其分为对照组与观察组,各50例。对照组接受术前常规护理与术后盆底肌电刺激,观察组在此基础上给予术前量化排尿训练。比较两组干预前后尿流动力学及排尿情况,并观察尿管拔除后24 h内及术后3个月排尿障碍发生情况。结果 干预后,两组膀胱容量、膀胱逼尿肌压力、尿流率、排尿间隔时间、每次尿量均高于干预前,且观察组高于对照组,差异有统计学意义(P<0.05);干预后,两组夜尿次数均少于干预前,且观察组少于对照组,差异有统计学意义(P<0.05);观察组尿管拔除后24 h内、术后3个月排尿障碍发生率均低于对照组,差异有统计学意义(P<0.05)。结论 应用术前量化排尿训练联合术后盆底肌电刺激可改善前列腺癌根治术后患者膀胱功能,提高排尿及控尿能力,降低排尿障碍发生率。 展开更多
关键词 前列腺癌 量化排尿训练 盆底肌电刺激 排尿障碍
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妊娠早、中期妇女尿碘/尿肌酐比值与亚临床甲状腺功能减退症合并自身抗体阳性的相关性
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作者 梁愿 王青 +3 位作者 吴芳 余红岚 许小红 周佳敏 《黑龙江医学》 2024年第8期927-930,共4页
目的:探讨妊娠早、中期妇女尿碘/尿肌酐比值(UIC/UCr)与亚临床甲状腺功能减退症(SCH)合并自身抗体阳性的相关性。方法:回顾性选取2018年1月—2021年6月贵阳市第一人民医院进行孕检的妊娠早、中期SCH孕妇作为研究对象,依据甲状腺自身抗... 目的:探讨妊娠早、中期妇女尿碘/尿肌酐比值(UIC/UCr)与亚临床甲状腺功能减退症(SCH)合并自身抗体阳性的相关性。方法:回顾性选取2018年1月—2021年6月贵阳市第一人民医院进行孕检的妊娠早、中期SCH孕妇作为研究对象,依据甲状腺自身抗体检测结果,将其分为:妊娠早、中期甲状腺抗体阳性组;妊娠早、中期甲状腺抗体阴性组;另选取同时期进行检查的妊娠早、中期健康孕妇作为对照组,每组各100例,共计300例,观察甲状腺过氧化物酶抗体(TPOAb)、甲状腺球蛋白抗体(TgAb)、UIC/UCr、促甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT3)、血清游离甲状腺素(FT4)等指标。结果:妊娠早期三组孕妇一般临床资料比较,差异无统计学意义(P>0.05),妊娠中期三组孕妇收缩压(SBP)、舒张压(DBP)比较,差异有统计学意义(F=7.024、11.357,P<0.05);UIC/UCr分析显示,与其他组别比较,妊娠早、中期阳性组孕妇均值和百分位分布数值最低;甲状腺激素及抗体水平比较,除FT3和FT4外,妊娠早、中期阳性组孕妇UIC/UCr、TPOAb、TgAb和TSH水平与健康组和阴性组比较,差异有统计学意义(F=71.710、279.102、130.017、275.949、22.991、220.702、288.882、184.459,P<0.001);相关性分析结果显示,UIC/UCr与TSH、TgAb、TPOAb水平呈负相关;多元线性回归分析结果发现,UIC/UCr、TSH是TPOAb、TgAb的主要影响因素。结论:妊娠早、中期SCH合并自身抗体阳性孕妇,UIC/UCr显著偏低且与TPOAb、TgAb关系密切,建议在临床中加强UIC/UCr指标观察。 展开更多
关键词 妊娠早、中期 尿碘尿肌酐比值 亚临床甲状腺功能减退症 甲状腺自身抗体阳性
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C-H-F氛围下金刚石薄膜的低温CVD生长过程分析
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作者 简小刚 梁晓伟 +4 位作者 姚文山 张毅 张斌华 陈哲 陈茂林 《金刚石与磨料磨具工程》 CAS 2024年第1期15-21,共7页
基于第一性原理的密度泛函理论对C-H-F氛围下低温CVD金刚石薄膜的生长过程进行仿真分析,计算H、F原子在氢终止金刚石表面发生萃取反应的吸附能、反应热与反应能垒,并分析CF_(3)、CF_(2)、CF 3种生长基团在带有活性位点基底上的吸附。结... 基于第一性原理的密度泛函理论对C-H-F氛围下低温CVD金刚石薄膜的生长过程进行仿真分析,计算H、F原子在氢终止金刚石表面发生萃取反应的吸附能、反应热与反应能垒,并分析CF_(3)、CF_(2)、CF 3种生长基团在带有活性位点基底上的吸附。结果表明:与H原子相比,F原子更容易在氢终止金刚石表面萃出H,并以HF形式脱附,且在C-H-F氛围下有利于在低温时产生更多的活性位点;CF_(3)、CF_(2)、CF基团在吸附后的结构和吸附能绝对值都更有利于金刚石相的生成,适当提高CF_(3)、CF_(2)、CF基团的浓度有助于实现金刚石相的更高速率生长。 展开更多
关键词 CVD金刚石薄膜 沉积机制 第一性原理 吸附 表面化学反应
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新型纳米杂化长链烷基/氨基共改性倍半硅氧烷防水剂的合成与性能研究
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作者 李小燕 安秋凤 +1 位作者 焦岚姣 杨博文 《陕西科技大学学报》 2024年第2期96-102,共7页
随着欧盟环保要求对PFOA、PFOS、APEO等含氟化合物的严格限制,无氟防水剂成为织物整理剂的主流.基于此,本研究将端环氧聚二甲基硅氧烷(α,ω-ESO)与N-β-(氨乙基)-γ-氨丙基甲基二甲氧基硅烷(KH-602)先氨解开环合成硅氧烷基封端的聚硅... 随着欧盟环保要求对PFOA、PFOS、APEO等含氟化合物的严格限制,无氟防水剂成为织物整理剂的主流.基于此,本研究将端环氧聚二甲基硅氧烷(α,ω-ESO)与N-β-(氨乙基)-γ-氨丙基甲基二甲氧基硅烷(KH-602)先氨解开环合成硅氧烷基封端的聚硅氧烷反应性中间体(AESO),再将其与正硅酸乙酯(TEOS)及辛基三乙氧基硅烷(OTES)进行水解缩聚,合成了一种新型纳米杂化长链烷基/氨基共改性倍半硅氧烷树脂,并以其制备得到防水剂RAPS@SiO_(2).以棉织物布样作为应用对象,用FT-IR、XRD、SEM、接触角测量仪等仪器对其进行表征测试.结果表明:与空白织物相比,采用3%浓度RAPS@SiO_(2)防水剂经一浸一轧工艺处理后的棉织物在保持原有光泽的同时,在防水性、柔软度等方面有明显提升,水接触角WCA=151.7°,滚动角SA=9.2°,静态吸水时间达到195 min,并且改性织物经过5次循环水洗、100次磨损后,仍然具有良好的疏水性能.无氟防水剂RAPS@SiO_(2)的开发为制备环境友好型超疏水织物防水剂提供新思路. 展开更多
关键词 无氟 改性聚硅氧烷 超疏水 防水剂
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提升杂环芳纶复合性能的研究进展
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作者 罗龙波 吕钧炜 +2 位作者 翟文 张殿波 刘向阳 《航空材料学报》 CAS CSCD 2024年第2期117-124,共8页
杂环芳纶是指主链中含有芳杂环(通常为苯并咪唑)的一类对位芳纶,其具有轻质、高强高模、高耐热、耐溶剂等优异性能。相比典型的芳纶Ⅱ纤维,杂环芳纶具有更加优异的力学性能,目前在我国的航空航天和防弹防护等领域得到了实际的应用。然而... 杂环芳纶是指主链中含有芳杂环(通常为苯并咪唑)的一类对位芳纶,其具有轻质、高强高模、高耐热、耐溶剂等优异性能。相比典型的芳纶Ⅱ纤维,杂环芳纶具有更加优异的力学性能,目前在我国的航空航天和防弹防护等领域得到了实际的应用。然而,与其他有机纤维类似,杂环芳纶由于表面惰性,其与树脂的复合性能相对较低,限制了其在先进复合材料领域的应用。本文从杂环芳纶表面改性和结构设计两方面出发,总结近年来提高杂环芳纶复合性能的设计思路、技术手段和研究成果,展望其在先进复合材料应用领域的发展趋势,为有机纤维的界面设计及改善界面粘接性提供帮助和参考。 展开更多
关键词 杂环芳纶 树脂基复合材料 直接氟化 层间剪切强度
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原发性痛风患者24 h尿液离子含量及其与肾结石的关系
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作者 张雷 何流 杨敏 《临床和实验医学杂志》 2024年第3期289-293,共5页
目的 探讨原发性痛风患者24 h尿液离子含量及其与肾结石的关系。方法 研究方法为回顾性分析,观察对象为2021年1月至2023年1月广安市人民医院入院的200例原发性痛风患者。超声检查显示,200例原发性痛风患者中122存在肾结石(肾结石阳性组)... 目的 探讨原发性痛风患者24 h尿液离子含量及其与肾结石的关系。方法 研究方法为回顾性分析,观察对象为2021年1月至2023年1月广安市人民医院入院的200例原发性痛风患者。超声检查显示,200例原发性痛风患者中122存在肾结石(肾结石阳性组),78例无肾结石(肾结石阴性组);160例存在下肢关节尿酸盐晶体沉积;DECT确诊68例尿酸盐结石(DECT阳性组),132例无肾结石(DECT阴性组)。比较肾结石阳性组与肾结石阴性组,DECT阳性组与DECT阴性组的临床资料与超声影像资料,对尿液离子含量与肾结石之间的相关性及肾结石形成危险因素予以分析;同时,将双能CT(DECT)影像结果作为肾尿酸盐结石诊断金标准,分析尿液离子含量对痛风伴发肾尿酸盐结石的诊断价值。结果 肾结石阳性组的痛风病程为(83.91±30.53)个月,明显长于肾结石阴性组[(48.64±26.52)个月],24 h尿草酸总量为(28.54±20.63) mg/24 h,明显高于肾结石阴性组[(20.09±9.74) mg/24 h],24 h尿枸橼酸总量为(355.63±219.52)mg/24 h,明显低于肾结石阴性组[(506.24±315.32) mg/24 h],差异均有统计学意义(P<0.05)。DECT阳性组患者痛风病程为(108.23±72.14)个月,明显长于DECT阴性组[(49.05±28.31)个月],血尿酸、24 h尿草酸总量、24 h尿尿酸总量分别为(522.98±109.14)μmol/L、(28.47±10.71) mg/24 h、(1 684.11±811.08) mmol/24 h,均明显高于DECT阴性组[(479.36±103.32)μmol/L、(23.54±10.82) mg/24 h、(1 517.81±886.53) mmol/24 h],24 h尿枸橼酸总量为(391.63±261.14) mg/24 h,明显低于DECT无阴性组[(555.91±316.24) mg/24 h],差异均有统计学意义(P<0.05)。痛风伴发肾尿酸盐结石诊断中24 h尿尿酸总量的ROC曲线下面积为0.202,无预测价值;24 h尿枸橼酸总量的ROC曲线下面积为0.672(95%CI:0.558~0.782),最佳预测值为272.5 mg(敏感度为0.938,特异度为0.518);24 h尿草酸的ROC曲线下面积为0.621(95%CI:0.512~0.730),最佳预测值为13.2 mg(敏感度为0.98,特异度为0.73)。Logistic回归分析显示,原发性痛风患者超声检查发现肾结石危险因素主要有低24 h尿枸橼酸总量、高血尿酸及长痛风病程(P<0.05);原发性痛风患者肾尿酸盐结石危险因素主要有低24 h尿枸橼酸总量、高血肌酐及长痛风病程(P<0.05)。结论 原发性痛风患者伴发肾尿酸盐结石时具有24 h尿草酸总量高、24 h尿枸橼酸总量低的特点;24 h尿草酸总量、24 h尿枸橼酸总量对痛风伴发肾尿酸盐结石具有较好的诊断价值。低24 h尿枸橼酸总量、长痛风病程是原发性痛风患者发生肾结石的重要危险因素。 展开更多
关键词 原发性痛风 24 h尿液离子含量 肾结石 诊断价值
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硝酸钍法测定排渣中氟含量的方法改进研究
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作者 金文进 王若钦 《当代化工研究》 CAS 2024年第3期71-73,共3页
硝酸钍滴定法因为其简单快速而成为氟化工生产中氟含量测定的的重要方法。为了提高硝酸钍法测定排渣中氟含量的准确度,减少试验带来的误差,以X射线荧光光谱法为对照,对实验过程中的样品称样量、溶样及酸度调节等各个因素进行了试验研究... 硝酸钍滴定法因为其简单快速而成为氟化工生产中氟含量测定的的重要方法。为了提高硝酸钍法测定排渣中氟含量的准确度,减少试验带来的误差,以X射线荧光光谱法为对照,对实验过程中的样品称样量、溶样及酸度调节等各个因素进行了试验研究,以期优化实验操作步骤。结果表明:样品研磨均匀,样品中盐酸处理干净并采用广范试纸调节酸度后按操作规程进行检测,与对照相比,不同分析者的结果异常,当用pH计调节滴定液的酸度为3.2左右时检测,该方法与X射线荧光光谱法结果吻合较好,检测结果准确可靠,可以用于测定排渣中氟的含量。 展开更多
关键词 氟含量 硝酸钍 方法
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响应曲面法优化高效除氟药剂的研制及除氟机理
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作者 章丽萍 姚瑞涵 +5 位作者 赵晓曦 雷文波 李蕙彤 战永祺 孙华冉 高乙清 《洁净煤技术》 CAS CSCD 2024年第1期217-227,共11页
我国电子、光伏、无机氟化工、煤矿开采、煤基化工等行业产生的废水普遍存在氟化物超标问题,除氟药剂法作为废水除氟的新方法,存在投药量及污泥产生量较大等问题。采用响应曲面BBD法对该除氟药剂的制备条件进行试验设计和优化,并与常用... 我国电子、光伏、无机氟化工、煤矿开采、煤基化工等行业产生的废水普遍存在氟化物超标问题,除氟药剂法作为废水除氟的新方法,存在投药量及污泥产生量较大等问题。采用响应曲面BBD法对该除氟药剂的制备条件进行试验设计和优化,并与常用混凝剂除氟性能进行对比。通过扫描电子显微镜分析(SEM)、X射线粉末衍射(XRD)分析手段对不同制备阶段除氟药剂进行表征分析,结合处理后上清液残留元素水平和各元素利用率对除氟机理进行探究。结果表明:除氟药剂最优制备条件为n(M)/n(Si)(M为金属总量)为44.91、n(Al)/n(Mg)为40.64、n(Al)/n(Fe)为34.92,在该条件下所制备的除氟药剂在投药量1.35 g/L时,氟离子质量浓度由20 mg/L降至0.71 mg/L,达到GB 3838—2002《地表水环境质量标准》Ⅲ类标准限值1.0 mg/L以下,氟离子去除率达96.45%,响应曲面法建立的模型相关系数R 2为0.9690;对于初始氟质量浓度10~200 mg/L的含氟水样,除氟药剂按比例投加,上清液剩余氟质量浓度均小于1.0 mg/L;与常用混凝剂的除氟性能顺序为:除氟药剂>PAC(聚合氯化铝)>PAFC(聚合氯化铝铁)>PFS(聚合硫酸铁);SEM和XRD表征分析发现除氟药剂形态和结构均发生改变,通过反应聚合形成多种多羟基聚合物,这些多羟基聚合物与氟离子间发生离子交换,从而去除氟离子;通过对上清液残留进行元素分析,结合所投加除氟药剂中各金属元素浓度,分析得出铝、硅、铁、镁的元素利用率分别为99.98%、97.16%、92.22%和18.39%;除氟药剂对多种实际含氟工业废水均高效且适用。 展开更多
关键词 除氟药剂 响应曲面法 除氟性能 除氟机理 元素利用率
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青少年体内35种抗生素和4种β-受体激动剂的测定及暴露现状分析
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作者 胡小键 李振环 +2 位作者 谢琳娜 付慧 朱英 《色谱》 CAS CSCD 2024年第2期185-193,共9页
为了解我国青少年体内抗生素和β-受体激动剂的暴露水平,本研究采用同位素稀释-高通量全自动固相萃取-超高效液相色谱-串联质谱法测定某中学442名青少年(11~15岁)尿液中的7类共35种抗生素(5种大环内酯类、4种四环素类、10种喹诺酮类、3... 为了解我国青少年体内抗生素和β-受体激动剂的暴露水平,本研究采用同位素稀释-高通量全自动固相萃取-超高效液相色谱-串联质谱法测定某中学442名青少年(11~15岁)尿液中的7类共35种抗生素(5种大环内酯类、4种四环素类、10种喹诺酮类、3种β-内酰胺类、11种磺胺类、1种喹噁啉类和1种林可酰胺类)和4种β-受体激动剂的水平。尿样测定结果采用尿肌酐进行校正,所得到的样品检出率用于统计分析。采用皮尔森卡方检验对目标物检出率与性别、年龄和体重等级间的相关性进行分析。在调整了混杂因素后,采用Logistic回归模型来评估目标物检出率与不同组别间的相关性。分析结果发现,442名青少年中有397名青少年的尿液中检出抗生素或β-受体激动剂,总体检出率为89.8%。除喹噁啉类抗生素未被检出外,实验中共有6类27种抗生素和2种β-受体激动剂被检出,检出率为0.2%~59.0%;其中强力霉素、土霉素和阿奇霉素的检出率最高,检出率分别为59.0%、56.1%和34.6%;四环素类和大环内酯类抗生素是主要检出的两类抗生素,检出率分别为81.9%和42.3%;优先作为兽用的抗生素检出率最高(85.1%),其次为人用抗生素(41.0%),β-受体激动剂的总体检出率为2.7%。统计分析发现,四环素类抗生素在男性青少年尿液中的检出率高于女性,男性检出风险是女性的2.17倍。大环内酯类抗生素在不同年龄组间的检出率存在差异,与11岁青少年组相比,12、13岁青少年组的检出风险更高。实验发现,大环内酯类抗生素的检出率与青少年的肥胖程度呈正相关;在调整了年龄和性别因素后,肥胖青少年尿液中大环内酯类抗生素的检出风险是正常体重者的2.35倍。研究结果表明,青少年普遍暴露于低剂量的抗生素,且食物和环境中的抗生素可能是青少年体内抗生素暴露的主要来源,大环内酯类抗生素的暴露可能与青少年的肥胖风险相关。 展开更多
关键词 超高效液相色谱-串联质谱 抗生素 β-受体激动剂 青少年 尿液 暴露分析
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1例高龄长期卧床男性患者并发紫色尿袋综合征的护理体会
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作者 苗苗 李君 +1 位作者 闫彤 孙依楠 《中西医结合护理》 2024年第3期93-95,共3页
本文总结1例高龄长期卧床男性患者并发紫色尿袋综合征(PUBS)的护理经验。PUBS的发生与尿路感染有关,护理人员应加强导管维护和相关尿路感染护理,同时给予饮食指导、便秘管理和心理护理,改善患者便秘症状,缓解负性情绪,提高治疗依从性,... 本文总结1例高龄长期卧床男性患者并发紫色尿袋综合征(PUBS)的护理经验。PUBS的发生与尿路感染有关,护理人员应加强导管维护和相关尿路感染护理,同时给予饮食指导、便秘管理和心理护理,改善患者便秘症状,缓解负性情绪,提高治疗依从性,加快患者康复。 展开更多
关键词 紫色尿袋综合征 高龄患者 卧床 尿路感染 细菌 便秘
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