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991.
实验教学在病理教学中占有重要地位。传统的挂图式实验教学法单一,不能准确定位镜下病理改变,讲解困难。根据院校自身病理切片资源及教材配套病理光盘图片资源自行制作病理实验教学图谱,具有方便、经济与教学内容配套及符合自身教学实际需要等优点,在实际教学中应用教学效果较好,对于高校病理实验教学具有一定的借鉴意义。 相似文献
992.
993.
Mingfeng Jiang Ling Xia Wenqing Huang Guofa Shou Feng Liu Stuart Crozier 《Medical engineering & physics》2009,31(8):979-985
Regularization is an effective method for the solution of ill-posed ECG inverse problems, such as computing epicardial potentials from body surface potentials. The aim of this work was to explore more robust regularization-based solutions through the application of subspace preconditioned LSQR (SP-LSQR) to the study of model-based ECG inverse problems. Here, we presented three different subspace splitting methods, i.e., SVD, wavelet transform and cosine transform schemes, to the design of the preconditioners for ill-posed problems, and to evaluate the performance of algorithms using a realistic heart-torso model simulation protocol. The results demonstrated that when compared with the LSQR, LSQR-Tik and Tik-LSQR method, the SP-LSQR produced higher efficiency and reconstructed more accurate epcicardial potential distributions. Amongst the three applied subspace splitting schemes, the SVD-based preconditioner yielded the best convergence rate and outperformed the other two in seeking the inverse solutions. Moreover, when optimized by the genetic algorithms (GA), the performances of SP-LSQR method were enhanced. The results from this investigation suggested that the SP-LSQR was a useful regularization technique for cardiac inverse problems. 相似文献
994.
[目的]探讨干部病房老年病人幸福度及相关因素.[方法]对干部病房老年病人进行方便取样调查,采用幸福度量表测量老年病人的生活满意度,采用社会支持评定量表评定老年病人的社会支持情况.[结果]干部病房老年病人的幸福度评分较高(32.30分±9.36分),以正性情感为主;干部病房老年病人的总体幸福度与有无配偶、社会支持水平、探望次数、文化程度密切相关;干部病房老年病人的负性情感与有无配偶、经济状况、性格类型有关.[结论]干部病房老年病人幸福度较高,与其社会支持水平、文化程度、经济状况有密切关系. 相似文献
995.
目的:研究未经正畸治疗的前牙有牙根吸收和无牙根吸收的错[牙合]患者的[牙合]及功能[牙合]特征,揭示引起牙根吸收的可能的[牙合]及咬合因素,为正畸治疗治疗前已有牙根吸收的患者提供可能的[牙合]及功能[牙合]参照标准。方法:用曲面断层片作为筛查方法,并用根尖片进一步确诊根尖吸收,对07年7月至08年3月在我正畸科初诊的患者进行调查,从中选择14名前牙根尖吸收为Ⅱ~Ⅲ度的错[牙合]畸形患者作为研究组,用年龄和性别作为控制标准随机选择14名无根尖吸收的错[牙合]畸形患者作为对照组,采用临床检查、模型分析和DenarMarkⅡ[牙合]架分析的方法研究两组的[牙合]和功能[牙合]特征,用spss14.0进行t检验统计分析。结果:两组的[牙合]特征不存在差异,临床检查和[牙合]架分析的结果均显示前牙牙根吸收组在侧方运动中前牙和后牙出现[牙合]干扰的数量高于对照组,其中[牙合]架分析发现牙根吸收患者在侧方运动中前牙出现[牙合]干扰的数量显著高于对照组(P〈0.05)。结论:未经治疗的错[牙合]畸形患者在侧方运动过程中前牙[牙合]干扰是发生前牙牙根吸收者可能原因。 相似文献
996.
Hai-Qing Ma Xiao-Ting Liang Jing-Jing Zhao Hui Wang Jian-Cong Sun Yi-Bing Chen Ke Pan Jian-Chuan Xia 《World journal of gastroenterology : WJG》2009,15(38):4844-4848
AIM: To investigate the expression of Neurensin-2 (NRSN2) in hepatocellular carcinoma (HCC) and its prognostic values in predicting survival. METHODS: The expression and prognostic significance of NRSN2 in HCC was examined by performing immunohistochemical analysis using a total of 110 HCC clinical tissue samples, and Western blotting analysis to further confirm the result. RESULTS: Decreased NRSN2 expression was shown in 70.9% cases. Loss of NRSN2 expression in HCC was significantly related to tumor size (P = 0.006). Larger tumor size was related to negative expression of NRSN2. Patients showing negative NRSN2 expression had a significantly shorter overall survival than those with positive expression (P = 0.008). Multivariate Cox regression analysis indicated that NRSN2 expression level was an independent factor of survival (P = 0.013). Western blotting analysis further confirmed decreased expression of NRSN2 in tumor tissues compared with non-tumorous tissues. CONCLUSION: Our study indicated that NRSIV2 could be a tumor suppressor gene for HCC and a candidate biomarker for long-term survival in HCC. 相似文献
997.
构建职业特色校园文化 培养高职学生职业精神 总被引:1,自引:0,他引:1
职业教育的健康发展和蓬勃兴旺首先依赖于职业精神的发扬光大。职业精神是与人们的职业活动紧密联系,具有自身职业特征的精神,它能鲜明地表达职业根本利益以及职业责任、职业行为上的精神要求。其基本要素有职业理想、职业态度、职业责任、职业技能、职业精神、职业良心、职业信誉和职业作风等。对于高职学生职业精神的培养, 相似文献
998.
老年妇科手术围手术期临床特点分析 总被引:3,自引:0,他引:3
目的探索老年妇科手术围手术期的临床特点。方法2001年1月至2004年3月老年妇女(年龄≥60岁)妇科手术病人50例为研究组,同期中年妇女(40~59岁)50例为对照组。监测麻醉前、达到完全阻滞平面时以及手术结束时病人的收缩压(SBP)、舒张压(DBP)、平均动脉压(MAP)、心率(HR)、血氧饱和度(SPO2)值,及术后最高体温、发热持续时间和其它并发症情况。结果两组病人达到完全阻滞平面时、手术结束时的SBP、DBP、MAP均较麻醉前显著降低(P<0.05),老年组下降幅度更大(P<0.001),而HR、SPO2及术后发热情况无明显差异。老年组术后并发症率16%,其中一例死于急性肺栓塞。中年组术后并发症率10%。结论老年妇女对妇科手术的耐受性较好,加强围手术期监护有助于提高手术的安全性。 相似文献
999.
Feng Xue Terumi Takahara Yutaka Yata Qiang Xia Kazunobu Nonome Eiji Shinno Masami Kanayama Shiro Takahara Toshiro Sugiyama 《Hepatology research》2008,38(8):810-817
Aim: There is growing evidence that the Rho/Rho-associated coiled coil-forming kinase (ROCK) signaling pathway is upregulated in tumors and plays a key role in cancer invasion and metastasis. Our aim was to test the anticancer effects of Rho/ROCK inhibitor, Y-27632, including possible mechanisms in a highly-metastasizing hepatocellular carcinoma (HCC) mouse model on its secretion of matrix metalloproteinase (MMP) and tumor progression.
Methods: Following orthotopic implantation of CBO140C12 HCC tumor fragments into the liver of mice, the mice were randomly assigned to a Y-27632-treated group or control group. After treatment for 4 weeks, specimens were obtained to evaluate tumor size, metastases, and immunohistochemical findings. In vitro , we examined the effects of Y-27632 and RhoC siRNA on MMP-2 and -9 expressions, invasiveness, and apoptosis in cultured tumor cells.
Results: Both RhoA and RhoC were upregulated in HCC-bearing livers, and Y-27632 significantly inhibited not only tumor growth and intrahepatic metastasis ( P < 0.05), but also tumoral MMP-9 expression. Moreover, Y-27632 treatment resulted in large necrotic areas in tumors. In vitro , Y-27632 and RhoC siRNA reduced MMP-2 and -9 expressions, as well as the chemotactic migration of tumor cells dose-dependently, and increased apoptosis eight times.
Conclusion: Y-27632 suppresses progression and limits the intrahepatic metastasis of established HCC. This could be linked to the decreased MMP expression and induction of apoptosis in tumor cells. Rho signaling may prove to be a productive target in anticancer therapy. 相似文献
Methods: Following orthotopic implantation of CBO140C12 HCC tumor fragments into the liver of mice, the mice were randomly assigned to a Y-27632-treated group or control group. After treatment for 4 weeks, specimens were obtained to evaluate tumor size, metastases, and immunohistochemical findings. In vitro , we examined the effects of Y-27632 and RhoC siRNA on MMP-2 and -9 expressions, invasiveness, and apoptosis in cultured tumor cells.
Results: Both RhoA and RhoC were upregulated in HCC-bearing livers, and Y-27632 significantly inhibited not only tumor growth and intrahepatic metastasis ( P < 0.05), but also tumoral MMP-9 expression. Moreover, Y-27632 treatment resulted in large necrotic areas in tumors. In vitro , Y-27632 and RhoC siRNA reduced MMP-2 and -9 expressions, as well as the chemotactic migration of tumor cells dose-dependently, and increased apoptosis eight times.
Conclusion: Y-27632 suppresses progression and limits the intrahepatic metastasis of established HCC. This could be linked to the decreased MMP expression and induction of apoptosis in tumor cells. Rho signaling may prove to be a productive target in anticancer therapy. 相似文献
1000.
Ming Zhou Haomin Song Xingyu Xu Alireza Shahsafi Yurui Qu Zhenyang Xia Zhenqiang Ma Mikhail A. Kats Jia Zhu Boon S. Ooi Qiaoqiang Gan Zongfu Yu 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(14)
A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (3–6). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (7–9) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (7–9). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (7–9), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime. 相似文献