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991.
Liu  Xiaoyun  Hou  Zhenghua  Yin  Yingying  Xie  Chunming  Zhang  Haisan  Zhang  Hongxing  Zhang  Zhijun  Yuan  Yonggui 《Brain imaging and behavior》2021,15(3):1420-1426
Brain Imaging and Behavior - This study aimed to examine the cerebral cortex characteristics (thickness, surface area, and curvature) in patients with major depressive disorder (MDD), and explore...  相似文献   
992.
993.
目的 探讨超声清洗时间和消毒灭菌频率对镍钛根管锉的抗拉性能的影响,以了解超声清洗和高温高压消毒灭菌法在镍钛根管锉灭菌中应用的安全性和可行性.方法 采用全新的ProTaper S2锉和F2锉各25支,分为5组:标准组(未处理)、对照组(未超声-高压灭菌)、A组(超声震荡50 min+高压灭菌5次)、B组(超声震荡100 min+高压灭菌10次)、C组(超声震荡150 min+高压灭菌15次),分别用万能测试仪对其进行抗拉伸强度的性能试验.结果 S2及F2的标准组之间的抗拉伸强度差异无统计学意义(P>0.05),提示样本间不存在差异性;经不同时间超声清洗及不同次数高温高压处理的S2镍钛锉抗拉伸强度测试结果显示:对照组、A组、B组、C组分别为(76.58±4.87)MPa、(71.00±5.39)MPa、(72.33±3.43)MPa、(66.81±4.08)MPa;F2镍钛锉抗拉伸强度结果分别为:(111.75±6.83)MPa、(110.46±3.88)MPa、(107.29±3.89)MPa、(94.53±6.61)MPa;A、B组与对照组的ProTaper S2锉和F2锉的抗拉强度差异均无统计学意义(P>0.05),即镍钛锉经超声震荡50 min+高压灭菌5次及超声震荡100 min+高压灭菌10次消毒后,其抗拉伸强度无明显影响;C组与对照组间差异存在统计学意义(P<0.05),即镍钛锉经超声震荡150 min+高压灭菌15次消毒后,对其抗拉伸强度有影响.结论 常规超声-高压灭菌消毒超过一定频率可能增加ProTaper系统镍钛根管锉折断可能性.  相似文献   
994.
Objective: To investigate the expression and correlation of transforming growth factor-β1 (TGF-β1) and fibroblast growth factor receptor 4 (FGFR4) in human hepatocellular carcinoma (HCC) and the relationship with clinicopathological features and prognosis.Materials and methods: The expression of TGF-β1 and FGFR4 in 126 HCC samples was detected immunohistochemically. Combined with clinical postoperative follow-up data, the expression of TGF-β1 and FGFR4 in HCC and the relationship with the prognosis of patients were analyzed by statistically.Results: The positive expression rate of TGF-β1 was 84.1% (106/126) in tumors, and that in peritumoral liver tissues was 64.3% (81/126); the positive expression rate of FGFR4 in tumors was 74.6% (94/126) and that in peritumoral liver tissues was 57.1% (72/126). The expression of TGF-β1 and FGFR4 in the carcinoma tissues was significantly higher than that in peritumoral liver tissues (p < 0.05). Intratumoral TGF-β1 and FGFR4 expression was associated with TNM stage (p < 0.05). TGF-β1 and FGFR4 expression levels didn''t significantly correlate with other clinicopathological parameters, including age, sex, tumor size, serum AFP level, tumor differentiation, lymph node metastasis, etc. (p > 0.05). TGF-β1 expression was positively correlated with FGFR4 expression (r = 0.595, p < 0.05). Patients with positive FGFR4 or TGF-β1 expression had shorter overall survival compared with negative expression (p < 0.05).Conclusions: The expression of TGF-β1 and FGFR4 could make synergy on the occurrence and progression of HCC, and may be used as prognosis indicators for HCC patients.  相似文献   
995.
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   
996.
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   
997.
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   
998.
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   
999.
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   
1000.
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