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排序方式: 共有146条查询结果,搜索用时 15 毫秒
1.
目的:了解转化生长因子β1(TGF-β1)对人牙髓细胞微丝和微管骨架的作用。方法:I型胶原酶消化组织块法体外培养人牙髓细胞,以20ng/ml的TGF-β1处理细胞,分别在第30min、1、6和24h收集细胞爬片,BODYPY-Phalloidin对微丝作直接荧光染色、Rhodamine RedTM对微管蛋白α(tubulin-α)作间接免疫荧光染色,采用激光扫描共聚焦显微镜观察TGF-β1作用于牙髓细胞后不同时间点微丝和微管的变化情况。结果:TGF-β1作用于人牙髓细胞后,微丝出现解聚重组现象,在30min时间点,肌动蛋白(actin)在细胞膜下聚合成纤维形肌动蛋白F-actin,同时胞质内的F-actin解聚,6h解聚最明显,24h后可见胞质内微丝重组。观察的各时间点,微管结构未见明显解聚重组现象。结论:TGF-β1能够使牙髓细胞微丝骨架重组。  相似文献   
2.
本文应用富里叶变换形状测试技术(FTP),针对人体关节测试研究,并从实际应用角度分析了FTP技术的误差及其改进方法,对标准平板和标准圆柱面的测定结果表明,精度可以达到0.05mm以上。  相似文献   
3.
In order to detect rapid eye movements (REM) automatically, the Discrete Wavelet Transform was applied to each 8-s segment of electrooculogram (EOG) data for 30 min of 8 h of normal sleep. The Haar function was used as an analysing wavelet because this function is similar to the REM waveform. By shifting the phase of the analysing wavelet by pi/4 of the function, 96% of REM could be detected. The artifacts caused by body movements could be detected simultaneously by this method. Computing time required for the detection of REM was only 11 s for 30 min EOG data.  相似文献   
4.
This work presents an automatic method for distortion correction and calibration of intra-operative spine X-ray images, a fundamental step for the use of this modality in computer and robotic assisted surgeries. Our method is based on a prototype calibration drum, attached to the c-arm intensifier during the intervention. The projections of its embedded fiducial beads onto the X-ray images are segmented by the proposed method, which uses its calculated centroids to undo the distortion and, afterwards, calibrate the c-arm. For the latter purpose, we propose the use of a constrained version of the well known Direct Linear Transform (DLT) algorithm, reducing its degrees of freedom from 11 to 3. Experimental evaluation of our method is included in this work, showing that it is fast and more accurate than other existing methods. The low segmentation error level also ensures accurate calibration of the c-arm, with an expected error of 4% in the computation of its focal distance.  相似文献   
5.
We report an extremely rare case of acute myelomonocytic leukemia (M4) with an MLL‐ELL fusion gene lacking the PML‐RARα rearrangement that transformed from hypergranular acute promyelocytic leukemia (APL) without showing any karyotypic evolution. The treatment was effective with chemotherapy for M4 and idarubicin plus a cytarabine‐based chemotherapy protocol without ATRA.  相似文献   
6.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
7.
8.
The arterial blood pressure waveform is variable during left ventricular assistance. The aim of this study is to examine the correlation between the left ventricular assist device (LVAD) condition and the arterial blood pressure waveform in a fixed cardiac output condition using a mock circuit. This mock circulation loop was composed of an aortic compliance chamber, a left atrial compliance chamber, a pneumatic pulsatile pump as a native heart, and a rotary blood pump representing the LVAD with left atrial drainage. The Fast Fourier Transform technique was utilized to analyze the arterial blood pressure waveform and calculate the pulsatility index (PI) and the pulse power index (PPI). The PI and PPI decreased with the increase of the LVAD rotational speed, exponentially. There was a significant negative correlation between the PI, PPI, and the LVAD rotational speed, flow rate, and assist ratio. The best correlation was observed between the PPI and the assist ratio (r = 0.986). From this viewpoint, an ideal LVAD condition may be estimated from the pulsatility change of the arterial blood pressure waveform.  相似文献   
9.
目的探讨腹膜纤维化的防治措施。方法Wistar大鼠30只随机分成三组。A组为模型组,每日腹腔注射4.25%的百特透析液20ml,B组为给药组每日腹腔注射透析液同时灌胃给药(血管紧张素转换酶抑制剂)一平苏,C组为空白对照组,每日腹腔注入生理盐水20ml。试验开始30天后取大鼠腹膜作病理组织学检查,同时收集血清和腹透液测定转化生长因子-β。结果A组和B组的腹膜明显纤维化并且转化生长因子-β血清和腹透液中都有增加,与C组差异都有显著性。结论高糖可以诱导腹膜纤维化。腹膜纤维化时转化生长因子-β血清和腹透液中都升高并且可被一平苏抑制。3平苏有抗腹膜纤维化的作用。  相似文献   
10.
The early clinical experience with a 3-Dimensional Fourier Transform Gradient Echo sequence with fat suppression in the evaluation of breast masses is reported. Ten female patients with breast malignancies were pre-operatively evaluated with this sequence and the results compared with the pathological specimens. The scanning protocol included a noncontrast sequence followed by an immediate post-contrast sequence (completed 4.5 min after intravenous contrast injection) and a delayed sequence. Images were assessed for maximum lesion and parenchymal enhancement, lesion size and additional enhancing abnormalities. In six patients, malignant masses enhanced maximally on the immediate post-contrast sequence with parenchyma enhancing maximally on delayed images. In three cases, there was preferential enhancement of malignant lesions over normal parenchyma but to a similar degree on both post-contrast sequences. In one case, both the lesion and parenchyma enhanced maximally on the delayed sequence. Magnetic resonance assessed lesion size accurately and also detected satellite malignancies in one case. However, lesion grade, associated in situ carcinoma and lymphovascular invasion did not impact on lesion enhancement. In this small series, a contrast-enhanced, fat-suppressed 3-D Gradient Echo Sequence detected breast carcinoma with high sensitivity. The technique holds promise but further evaluation is required.  相似文献   
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