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991.
In this work, an efficient and sensitive fluorometric sensor was developed to detect silver ions (Ag+). It is based on the cytosine–Ag+–cytosine (C–Ag+–C) structure via a dual-signal amplification strategy using glucose oxidase (GOx) and the hybridization chain reaction (HCR). A silver-coated glass slide (SCGS) acts as an ideal material for separation. Cytosine rich (C-rich) capture DNA (C-DNA) assembled themselves on the SCGS via Ag–S bonds and hybridized with signal DNA (S-DNA) to trigger the HCR. With specific base-pairing, the S-DNA and HCR products bind on the SCGS. Then, the GOx–biotin–streptavidin (SA) complexes bind to the HCR products through SA–biotin interactions. Owing to the formation of a particular C–Ag+–C structure between two neighboring C-rich C-DNA on the SCGS, the C-DNA/S-DNA/HP1-GOx/HP2-GOx complex gradually moved away from the SCGS as the concentration of Ag+ increased and the combined GOx fell into the buffer. H2O2 could be generated during the oxidation of glucose, catalyzed by GOx in the buffer. Afterward, H2O2 could oxidize the substrate (3-(p-hydroxyphenyl)-propanoic acid) when Horseradish peroxidase was present, giving rise to blue fluorescence. The proposed strategy reached a limit of detection (LOD) of 1.8 pmol L−1 with a linear detection range of 5 to 1000 pmol L−1 for Ag+. Moreover, this assay has been commendably used for the detection of Ag+ in actual samples with fairly good results.An assay for Ag+ based on a C–Ag+–C structure by utilizing a HCR/GOx dual-signal amplification strategy and SCGS as an ideal separation material. 相似文献
992.
谢添添 《中外女性健康研究》2021,(5):67-68
目的:观察并分析在头位难产助产护理中对产妇应用徒手旋转的效果。方法:选取本院产科收治的84例头位难产产妇为研究对象,按入院顺序将其分为对照组(42例,常规助产护理)与观察组(42例,徒手旋转助产护理)。评价两组的助产护理效果。结果:观察组产妇自然分娩率及新生儿Apgar评分显著高于对照组,第二产程时间、产后出血量以及新生儿不良反应发生率则明显低于对照组,数据差异明显,P<0.05。结论:徒手旋转的助产护理方式可缩短头位难产产妇的产程时间,降低剖宫产率及新生儿并发症发生率,确保分娩的顺利进行。 相似文献
993.
目的调查ICU患者双上肢握力及髋关节屈曲拉力及其主要影响因素。
方法选取2019年4月至7月青海省人民医院77例ICU患者为研究对象,男性55例,女性22例,平均年龄(56.09±18.44)岁。收集患者一般病例资料(包括一般社会学资料,入住ICU后,出ICU前及出ICU时评价指标),测量其在入住ICU时和出ICU时双上肢握力及髋关节屈曲拉力。
结果患者入住ICU时及出ICU时,上肢握力分别为(22.14±10.91)kg、(23.22±12.01)kg,差异有统计学意义(t=2.490,P=0.015);髋关节屈曲拉力分别为(9.99±6.23)kg、(11.14±7.87)kg,差异有统计学意义(t=4.605,P<0.001)。患者出ICU时,ADL评分较入住ICU时有显著改善,差异有统计学意义(Z=4.401,P<0.001),患者营养不良比例、红细胞、血红蛋白较入住ICU时有显著性下降,差异有统计学意义(χ2=65.07,t=5.208,t=2.688,P<0.05),其余化验指标均无显著性改变(P>0.05)。患者上肢握力与年龄(r=-0.540)、性别(r=-0.415)、婚姻状况(r=-0.512)、住ICU天数(r=-0.304)、机械通气天数(r=-0.246)、人工气道天数呈显著性负相关(r=-0.224),与ADL评分(r=0.316)呈显著正相关;髋关节屈曲拉力与性别(r=-0.452)、营养状态(r=-0.334)呈显著负相关。
结论ICU患者上肢握力及髋关节屈曲拉力呈现较低水平,随着疾病恢复逐渐增强。对于高龄、女性、有吸烟史、有饮酒史及已婚的患者在住ICU期间要更加关注其肌肉健康状态,患者住ICU期间要根据病情尽早拔除人工气道、缩短机械通气的时间,同时要加强患者的营养,为预防ICU患者肌肉衰减做好预防工作。 相似文献
994.
Liu-Hong Shi Liang Zhou Yin-Jiao Lei Lian Xia Lei Xie 《World Journal of Clinical Cases》2021,9(15):3662-3667
BACKGROUNDFine-needle biopsy is an accurate and cost-efficient tool for the assessment of thyroid nodules. It includes two primary methods: Fine-needle capillary biopsy (FNCB) and fine-needle aspiration biopsy. Needle tract seeding (NTS) is a rare complication of thyroid fine-needle biopsy mainly caused by fine-needle aspiration biopsy rather than FNCB. Here, we present an extremely rare case of a papillary thyroid carcinoma (PTC) patient with FNCB-derived NTS. CASE SUMMARYWe report a 32-year-old woman with PTC who showed subcutaneous NTS 1 year after FNCB and thyroidectomy. NTS was diagnosed based on clinical manifestations, biochemistry indices, and imaging (computed tomography and ultrasound). Pathological identification of PTC metastases consistent with the puncture path is the gold standard for diagnosis. Surgical resection was the main method used to treat the disease. After surgery, thyroid function tests and ultrasound scans were performed every 3-6 mo. To date, no evidence of tumor recurrence has been observed.CONCLUSIONFNCB is a safe procedure as NTS is rare, and can be easily removed surgically with no recurrence. Accordingly, NTS should not limit the usefulness of FNCB. 相似文献
995.
Dong Xiao Zhenya Zang Natakorn Sapermsap Quan Wang Wujun Xie Yu Chen David Day Uei Li 《Biomedical optics express》2021,12(6):3450
Measuring fluorescence lifetimes of fast-moving cells or particles have broad applications in biomedical sciences. This paper presents a dynamic fluorescence lifetime sensing (DFLS) system based on the time-correlated single-photon counting (TCSPC) principle. It integrates a CMOS 192 × 128 single-photon avalanche diode (SPAD) array, offering an enormous photon-counting throughput without pile-up effects. We also proposed a quantized convolutional neural network (QCNN) algorithm and designed a field-programmable gate array embedded processor for fluorescence lifetime determinations. The processor uses a simple architecture, showing unparallel advantages in accuracy, analysis speed, and power consumption. It can resolve fluorescence lifetimes against disturbing noise. We evaluated the DFLS system using fluorescence dyes and fluorophore-tagged microspheres. The system can effectively measure fluorescence lifetimes within a single exposure period of the SPAD sensor, paving the way for portable time-resolved devices and shows potential in various applications. 相似文献
996.
997.
灼口综合征(burning mouth syndrome,BMS)病因尚不明确,尚无有效的治疗方法,临床患者日渐增多。BMS是以舌部为主要发病部位,以烧灼样疼痛为典型表现的一组综合征。常不伴有明显的临床损害体征;无特征性的组织病理变化。由于持续的疼痛困扰以及不理想的用药效果,患者就医时往往有较高的期望值,就医后容易有较大的失望感,存在医患纠纷的隐患。作者对BMS的流行病学现状、临床表现、病因、分型、诊断标准及治疗等方面进行综述,以期对BMS的临床诊疗提供指导。 相似文献
998.
999.
Meng‐Hsuan Ho Hatice Hasturk Daphne F. Young Hua Xie 《Molecular oral microbiology》2020,35(5):193-201
Chronic periodontitis is one of the most common infectious inflammatory diseases worldwide. Current therapeutic options for the disease are only partially and temporarily successful due to periodontal re‐emergence of pathogens such as Porphyromonas gingivalis, a keystone bacterium in the oral microbial communities, which elicits a dysbiosis between the microbiota and the host. Previously, we reported a peptide inhibitor of P. gingivalis (SAPP) that specifically targets P. gingivalis and reduces its virulence potential in vitro. Here, we show that SAPP can modulate the ability of P. gingivalis to suppress the host innate immune system. Using a cytokine array analysis, we found that the levels of several cytokines including IL‐6, IL‐8, and MCP‐1 in the culture media of human oral keratinocytes (HOKs) were significantly diminished in the presence of P. gingivalis. Whereas the levels of these cytokines were restored, at least partially, in the culture media of HOKs by SAPP treatment. Furthermore, we also observed in an ex vivo assay that SAPP efficiently inhibited biofilm primed formation by mixed‐species oral bacteria, and significantly dampened the abnormally innate immune responses induced by these bacteria. We also demonstrated, using a mouse model, that SAPP could prevent alveolar bone loss induced by P. gingivalis. Our results suggest that SAPP specifically targets P. gingivalis and its associated bacterial communities and could be envisioned as an emerging therapy for periodontitis. 相似文献
1000.
目的探讨原发性干燥综合征(pSS)患者唇腺组织中IL-7的表达及其与临床血清学参数间的关联。
方法收集2015年1月至2017年12月汕头市中心医院pSS患者135例,以及同期唇外伤正常对照个体12例。免疫组织化学法检测两组个体唇腺组织中IL-7的表达,分别评估腺上皮细胞与浸润淋巴细胞IL-7的表达情况。Pearson相关分析唇腺组织IL-7的表达与抗核抗体(ANA)、C3、C4、C反应蛋白(CRP)、IgG等血清学指标间的关联性。
结果IL-7在唇腺组织内淋巴细胞、腺泡导管及上皮细胞均可表达。浸润的淋巴细胞IL-7表达阳性率在pSS患者(88.14%,119/135)显著高于正常对照个体(8.3%,1/12),差异有统计学意义(χ2 = 46.82,P<0.001)。pSS患者唇腺组织中腺泡与导管上皮细胞与浸润淋巴细胞IL-7的表达相关(r = 0.27,P = 0.0012),未发现有浸润淋巴细胞IL-7表达与血清指标间的相关性。
结论pSS患者唇腺组织中腺体上皮细胞、淋巴细胞IL-7异常高表达,且两者表达情况紧密相关,提示IL-7的表达可能参与了pSS腺体与淋巴细胞的相互作用,可作为pSS唇腺干预一个新的治疗靶点。 相似文献