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11.
12.
目前,临床上已有关于钙剂、骨化三醇联合降钙素治疗对骨折患者骨痂组织中血管内皮生长因子(vascular endothelial growth factor,VEGF)、降钙素受体(Calcitonin Receptor,CTR)核心结合因子α1(corebindingfactorα1,Cbfα1)表达影响的研究较为少见[1]。鉴于此,本文通过研究碳酸钙、骨化三醇联合降钙素对骨折模型大鼠骨密度水平和骨痂组织中VEGF、CTR、Cbfα1表达的影响,旨在为临床治疗提供思路支持,现作以下报道。 相似文献
13.
Zhengxian Huang Nan Xie Haichao Liu Yuehan Wan Yue Zhu Ming Zhang Yifan Tao Han Zhou Xiqiang Liu Jinsong Hou Cheng Wang 《Journal of oral pathology & medicine》2019,48(9):788-798
It has been suggested that tumour‐infiltrating lymphocytes (TILs) are associated with the progression of oral squamous cell carcinoma (OSCC). However, the prognostic value of TILs is inconclusive due to the heterogeneity of immune cells within the tumour microenvironment. In this meta‐analysis, we aimed to assess the prognostic value of TILs in OSCC. The PubMed, Cochrane, Embase, Scopus and Web of Science databases were searched up to April 20, 2019, and 33 studies were ultimately included in this meta‐analysis. Our pooled meta‐analysis showed that high infiltration of CD8+ TILs, CD45RO+ TILs and CD57+ TILs favoured better overall survival (OS). However, high infiltration of CD68+ macrophages and CD163+ macrophages was associated with poor prognosis in OSCC. These findings suggest that CD8+ TILs, CD45RO+ TILs, CD57+ TILs, CD68+ macrophages and CD163+ macrophages might serve as novel prognostic factors and therapeutic targets in OSCC. 相似文献
14.
A Stable Q Compensated Reverse Time Migration Method Based on Excitation Amplitude Imaging Condition
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Qingqing Li Li-Yun Fu Weijia Sun Wei Wei & Wanting Hou 《Communications In Computational Physics》2020,28(1):141-166
The stability and efficiency, especially the stability, are generally concerned
issues in Q compensated reverse time migration (Q-RTM). The instability occurs because of the exponentially boosted high frequency ambient noise during the forward
or backward seismic wavefield propagation. The regularization and low-pass filtering
methods are two effective strategies to control the instability of the wave propagation in Q-RTM. However, the regularization parameters are determined experimentally, and the wavefield cannot be recovered accurately. The low-pass filtering method
cannot balance the selection of cutoff frequency for varying Q values, and may damage
the effective signals, especially when the signal-to-noise ratio (SNR) of the seismic data
is low, the Q-RTM will be a highly unstable process. In order to achieve the purpose
of stability, the selection of cutoff frequency will be small enough, which can cause
great damage to the effective high frequency signals. In this paper, we present a stable Q-RTM algorithm based on the excitation amplitude imaging condition, which can
compensate both the amplitude attenuation and phase dispersion. Unlike the existing Q-RTM algorithms enlarging the amplitude, the exponentially attenuated seismic
wavefield will be used during both the forward and backward wavefield propagation
of Q-RTM. Therefore, the new Q-RTM algorithm is relative stable, even for the low
SNR seismic data. In order to show the accuracy and stability of our stable Q-RTM
algorithm clearly, an example based on Graben model will be illustrated. Then, a realistic BP gas chimney model further demonstrates that the proposed method enjoys
good stability and anti-noise performance compared with the traditional Q-RTM with
amplitude amplification. Compare the Q-RTM images of these two models to the reference images obtained by the acoustic RTM with acoustic seismic data, the new Q-RTM
results match the reference images quite well. The proposed method is also tested
using a field seismic data, the result shows the effectiveness of our proposed method. 相似文献
15.
目的研究吗啡依赖和戒断时大鼠杏仁核中神经甾体和氨基酸递质水平的变化。方法连续7天给予大鼠盐酸吗啡建立吗啡依赖模型。使用纳洛酮(2mg/kg)催促戒断,观察戒断症状并进行评分。将大鼠断头处死后,剥离大脑并分离出杏仁核,用液-液萃取和固相萃取法提取游离型和结合型神经甾体。神经甾体(包括脱氢表雄酮、孕烯醇酮、别孕烯醇酮、脱氢表雄酮硫酸酯和孕烯醇酮硫酸酯)的含量使用高效液相色谱-质谱法测定。甘氨酸、谷氨酸和γ-氨基丁酸的含量采用柱前OPA衍生-电化学检测-高效液相色谱法测定。结果与盐水对照组相比,吗啡依赖大鼠杏仁核中的脱氢表雄酮水平降低33 %(P<0·01)。与戒断对照组比较,吗啡戒断大鼠杏仁核中的孕烯醇酮和别孕烯醇酮水平分别升高45 %和42 %(P<0·05) ,γ-氨基丁酸水平降低18 %(P<0·01)。与吗啡依赖组比较,吗啡戒断组大鼠杏仁核中的孕烯醇酮和孕烯醇酮硫酸酯水平分别升高60 %和40 %(P<0·05) ,甘氨酸水平降低14 %(P<0·05)。结论吗啡依赖大鼠杏仁核中的脱氢表雄酮可能参与吗啡依赖的形成而与吗啡戒断症状的表达无关。其他神经甾体(包括孕烯醇酮、别孕烯醇酮和孕烯醇酮硫酸酯)则可能参与吗啡的戒断而与依赖的形成无关。纳洛酮催促戒断时,大鼠杏仁核中抑制性氨基酸递质的合成和释放受到抑制。表明大鼠杏仁核中的各种神经甾体和氨基酸递质在吗啡依赖和戒断时发生了不同的变化。 相似文献
16.
目的 研究乙型肝炎病毒(HBV)自身增强子I(enhancerI,ENHI)对HBV DNA疫苗免疫应答的影响。方法 采用PCR法以HBVadr亚型全基因DNA序列为模板分别扩增表面抗原(HBsAg)和HBsA-ENHI基因片段,重组到载体VR1012中,构建两种HBV DNA疫苗,转染CADS-7细胞及HepG2细胞并免疫BALB/c小鼠。采用蛋白印迹、ELISA、ELISPOT等方法检测其在COS-7和HepG2细胞内的表达及小鼠的体液及细胞免疫应答效果。结果 转染的HepG2和COS-7细胞均表达HBsAg;连接ENHI的HBV DNA疫苗转染HepG2细胞后HBsAg表达量明显升高,两种疫苗转染COS-7细胞表达HBsAg无明显差异;免疫小鼠后第2周产生HBsAb及HBsAg特异性细胞毒T淋巴细胞(CTL),两种疫苗免疫产生的HBsAb及HBsAg特异性CTL无明显差异。结论ENHI可使HBV DNA疫苗转染HepG2细胞表达HBsAg明显增加,对转染COS-7细胞表达HBsAg及接种BALB/C小鼠引起的免疫应答无明显影响。 相似文献
17.
实习护士的压力源分析及带教老师的应对方式 总被引:4,自引:0,他引:4
护理工作是脑力和体力相结合的双重劳动,对于接触这一工作不久的实习护十来说。由于特定的工作性质和职业的高要求,其身心承受很大的压力。为此,调查了我院115名实习护士压力的影响因素,所获得的信息将有助于临床工作者针对性地采取减轻压力措施,帮助护生掌握应对压力的有效策略,使实习护士在适度的压力状态下身心健康的学习工作,成为护理事业合格的后备力量。 相似文献
18.
用两株McAb及BA—ELISA法检测肺癌患者血清中肺癌相关抗原 总被引:1,自引:1,他引:0
肿瘤患者血清中肿瘤相关抗原含量甚微,通常需要高度敏感的测定系统方能进行检测.生物素-亲和素系统(BSA)是近年来建立的一种生物反应放大系统,由于BSA亲合力高、特异性强反应迅速,故自70年代后期引入免疫技术以来,大大改善和丰富了免疫学试验,成为新的检测系统.本实验用生物素标记两株抗人肺癌McAb——Lc86aE4和Lc86aC5,建立了BA-ELISA方法,并对肺癌患者血清中肺癌相关抗原(lung carcinoma associated antigen,LAA)进行了检测,证实BA-ELISA法具有特异、敏感及重复性好等优点. 相似文献
19.
Rolled finger gloves were used as ring tourniquets on a case of amputation injury of bilateral thumbs. Necrosis of soft tissue of the right thumb occurred due to mistakenly prolonged use of the tourniquet. Later the patient successfully underwent a toe-to-thumb transfer (modified wraparound procedure). The precautions in using finger tourniquets are stressed. 相似文献
20.
C L Hou 《中华整形烧伤外科杂志》1989,5(1):30-1, 77
Thirty cases of large pressure sores were treated by myocutaneous flaps (39 flaps) and the cure rate was 92%. Of them, 15 pressure sores were treated by gluteus maximus myocutaneous flaps, 12 in the greater trochanteric area by tensor fascia lata myocutaneous flaps, 7 in the ischiatic area by gracilis myocutaneous flaps and 4 in the ischiatic area biceps femoris myocutaneous flaps, 2 by a abductor hallucis myocutaneous flap and a flexor digitorum brevis myocutaneous flap. In author's opinion, myocutaneous flap transposition is simple, safe and reliable method in treating large pressure sores. These flaps increased the blood flow on recipient sites through its own intrinsic blood vessels so as to accelerate wound healing. 相似文献