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151.
The distribution of metallic ions in plant tissues is associated with their toxicity and is important for understanding mechanisms of toxicity tolerance. A quantitative histochemical method can help advance knowledge of cellular and subcellular localization and distribution of heavy metals in plant tissues. An immunohistochemical (IHC) imaging method for cadmium ions (Cd2+) was developed for the first time for the wheat Triticum aestivum grown in Cd2+-fortified soils. Also, 1-(4-Isothiocyanobenzyl)-ethylenediamine-N,N,N,N-tetraacetic acid (ITCB-EDTA) was used to chelate the mobile Cd2+. The ITCB-EDTA/Cd2+ complex was fixed with proteins in situ via the isothiocyano group. A new Cd2+-EDTA specific monoclonal antibody, 4F3B6D9A1, was used to locate the Cd2+-EDTA protein complex. After staining, the fluorescence intensities of sections of Cd2+-positive roots were compared with those of Cd2+-negative roots under a laser confocal scanning microscope, and the location of colloidal gold particles was determined with a transmission electron microscope. The results enable quantification of the Cd2+ content in plant tissues and illustrate Cd2+ translocation and cellular and subcellular responses of T. aestivum to Cd2+ stress. Compared to the conventional metal-S coprecipitation histochemical method, this new IHC method is quantitative, more specific and has less background interference. The subcellular location of Cd2+ was also confirmed with energy-dispersive X-ray microanalysis. The IHC method is suitable for locating and quantifying Cd2+ in plant tissues and can be extended to other heavy metallic ions.  相似文献   
152.

Background

With the expanding population of colorectal cancer (CRC) survivors in the United States, one concerning issue is the risk of developing second primary malignancies (SPMs) for these CRC survivors. The present study attempts to identify the incidence characteristics of SPMs after diagnosis of first primary colon cancer (CC) and rectal cancer (RC).

Methods

189,890 CC and 83,802 RC cases were identified from Surveillance, Epidemiology and End Results Program (SEER) database. We performed rate analysis on incidence trend of SPMs in both CC and RC. Expected incidence rates were stratified by age, race and stage, calendar year of first CRC diagnosis and latency period since first CRC diagnosis. The standardized incidence ratios (SIRs), measure for estimating risk of SPMs, were calculated for CC and RC respectively.

Results

The trends of incidence of SPMs in both CC and RC were decreasing from 1992 to 2012. Both CC and RC survivors had higher risk of developing SPMs (SIRCC = 1.13; SIRRC = 1.05). For CC patients, the highest risks of SPM were cancers of small intestine (SIR = 4.03), colon (SIR = 1.87) and rectum (SIR = 1.80). For RC patients, the highest risks of SPMs were cancers of rectum (SIR = 2.88), small intestine (SIR = 2.16) and thyroid (SIR = 1.46). According to stratified analyses, we also identified incidence characteristics which were contributed to higher risk of developing SPMs, including the age between 20 and 40, American Indian/Alaska Native, localized stage, diagnosed at calendar year from 2002 to 2012 and the latency between 12 and 59 months.

Conclusions

Both CC and RC survivors remain at higher risk of developing SPMs. The identification of incidence characteristics of SPMs is extremely essential for continuous cancer surveillance among CRC survivors.  相似文献   
153.
目的探讨对并发吸入性肺炎的长期鼻饲老年患者抗感染药物治疗和加强护理干预的效果。方法将100例长期采取鼻饲饮食的老年患者纳入研究对象,根据数字表的方式随机分为50例的对照组和50例的观察组。对照组患者给予常规护理,观察组患者给予抗感染药物和加强鼻饲饮食的护理干预,并通过适当的口腔护理和心理辅导来降低感染和改善患者不良的心理状态。对比两组患者护理后吸入性肺炎的减少情况,并比较两组患者护理后的心理状态和护理满意度。结果观察组患者给予抗感染药物和加强鼻饲饮食的护理干预,吸入性肺炎(10.00%)、腹泻(8.00%)和便秘的发生率(4.00%)明显低于对照组(38.00%,34.00%,30.00%);SAS评分(32.33±8.09)分和SDS评分(31.46±7.87)分明显低于对照组(48.57±12.15)分和(49.28±12.32)分;护理总满意度(98.00%)明显高于对照组(72.00%),组间比较差异有统计学意义(P0.05)。结论对长期鼻饲老年患者给予合理的抗感染药物和有效的护理干预,可以减少吸入性肺炎的并发情况,改善患者不良情绪,患者对护理的满意度也相应提高。  相似文献   
154.
目的:对比分析多种介入途径治疗门静脉系统血栓的临床疗效。方法:收集从2001年1月至2009年3月经我科治疗的37例门静脉系统(包括门静脉、肠系膜上、下静脉及脾静脉)血栓形成患者,根据介入治疗途径的不同分为三组:A组(13例)行经TIPS途径门静脉行碎栓溶栓及置管溶栓术;B组(19例)行直接经皮穿肝门静脉碎栓和或置管溶栓术;C组(5例)行经肠系膜上动脉置管溶栓治疗。所有的患者术后定期随访1-12个月,复查CT或彩超了解门静脉系统的血流变化及临床症状恢复情况。结果:A组:经治疗出院时11例(85%)患者门静脉完全再通,;1例(8%)门静脉血流部分再通,1例(8%)术后第二天因出血死亡。术后随访1、3、6、12月门静脉通畅率分别为:85%,77%,77%,62%;所有患者的临床症状均明显缓解。B组:经治疗出院时7例(37%)门静脉完全再通,9例(47%)部分再通,3例(16%)因出血中止溶栓;随访1、3、6月、12月门静脉通畅率分别为:32%,26%,16%,16%。C组:经治疗出院时5例(100%)患者门静脉均未再通,通畅率为0%,术后随访1-3个月内4例患者临床症状得到部分缓解。结论:经TIPS途径治疗后门静脉的再通率及临床症状改善均好于直接经皮穿肝及经肠系膜上动脉途径。经肠系膜上动脉置管溶栓法无法使已有侧支形成的门静脉主干复通,仅能一定程度缓解患者的临床症状。  相似文献   
155.
为明确工业配方中不同MgSO4添加量对枯草芽胞杆菌B201发酵过程及菌液保存的影响,采用单因素法设置5个MgSO4添加量梯度(质量分数,下同)( 0.13%、0.24%、 0.46%、0.87%、1.70%)。分别记录不同梯度MgSO4处理的发酵液灭菌前后pH值,以及发酵过程中的菌体形态的变化,统计发酵结束后细菌的发酵周期、活菌数和芽肥率,测量发酵结束后发酵液pH以及残糖和残氮含量。实验表明,MgSO4的不同添加量对菌株B201发酵及菌液保存均有显著影响。添加量为0.87%和1.70%处理组灭菌后培养基的pH较灭菌前升高,培养基由中性变为弱碱性。接种后12 h取样观察,菌体明显变形,视野内菌数较少,且随着MgSO4添加量的增加发酵液活菌数下降,残糖和残氮升高,不利于保存。MgSO4相对合适的添加量为0.13%、0.24%和0.46%,三种MgSO4添加量的发酵液活菌数、残氮含量无显著差异;MgSO4添加量为0.24%时菌株B201芽肥率最高为89.33%,而MgSO4添加量为0.13%和0.46%时,芽肥率分别为80%和82.67%;0.46%MgSO4添加量可加速菌株B201发酵进程,发酵周期较其他两个处理缩短45.8%。为提高菌株B201的发酵水平,降低其生产成本,综合考虑MgSO4的添加量以0.46%为宜。研究结果不仅为实验室菌株B201的发酵优化提供参考,还为培养基的优化拓宽了思路。  相似文献   
156.

Background and Objectives

Although there was growing evidence supporting the hypothesis that Notch1 was one of the few candidate genes linked with colorectal cancer (CRC) susceptibility, the precise level of Notch1 protein expression in benign and malignant colorectal diseases was still unknown. Our study has investigated the Notch1 expression in benign and malignant colorectal diseases as well as to investigate the role and clinicopathological significance of aberrant expression of Notch1 in CRC.

Methods

The protein expression of Notch1 was examined by immunohistochemistry in 901 clinical specimens with colorectal diseases, including 220 patients with ulcerative colitis, 232 patients with colorectal adenoma and 449 patients with colorectal cancer. Associations between the expression of Notch1 and various clinicopathological features, as well as survival status, were studied.

Results

Cytoplasmic Notch1 was expressed in 7.7% of patients with ulcerative colitis, 14.7% of patients with colorectal adenoma and 58.0% of patients with colorectal cancer, respectively. Colorectal cancer patients with high expression levels of Notch1 showed lower overall survival (OS) and disease-free survival (DFS) rates than those patients with low Notch1 expression.

Conclusions

Expression level of Notch1 was gradually increased from precancerous lesions to cancer. It might play as an oncogene in the CRC development, and might be potentially used as a biomarker for prognosis of CRCs.  相似文献   
157.
The digestive tract plays an important role in digestion and the acquisition of food energy. Understanding the impact of abiotic environments on digestive tract morphology is especially important for evolution of digestive tract across different environments. Here, we investigated altitudinal variation in digestive tract length in the Yunnan Pond Frog (Pelophylaxpleuraden) across five populations ranging from 1413 m to 1935 m a.s.1, in Ningnan County, Sichuan province in western China. Frogs were collected during the breeding season, from 1-5 June 2012. Our results revealed that females had longer digestive tract and relative digestive tract (i.e. digestive tract length / body size) lengths in com- parison to males, on average, but the differences between them decreased with increasing altitude. Digestive tract and relative digestive tract lengths increased with increasing altitude suggesting that a higher proportion of indigestible ma- terials may be consumed at high-altitude sites and result in a relative increase in digestive tract dimensions.  相似文献   
158.
小叶石楠果实中低极性化学成分GC-MS分析   总被引:1,自引:0,他引:1  
采用溶剂提取法从小叶石楠果实中提取低极性化学成分,并利用气相色谱—质谱仪对果实中的低极性化学成分进行分离和鉴定,同时用面积归一法测定各成分的相对百分含量。结果表明:已确认了25种成分,占果实中低极性化学成分的96.04%,其主要成分为亚麻酸甲酯(13.11%)、邻苯二甲酸二辛醇酯(10.13%)、角鲨烯(9.19%)、维生素E(8.67%)、十九烷(8.03%)。所鉴定的化合物多为该种植物中首次发现,为小叶石楠的进一步开发利用提供了科学依据。  相似文献   
159.
湿地土壤埋深对芦苇、香蒲种子萌发的影响   总被引:1,自引:0,他引:1  
土壤埋藏深度是影响湿地植物种子萌发与幼苗生长的重要因子。通过室内模拟实验,分析了松花江下游沿江湿地7种土壤埋深(0、5、10、15、20、25和30 mm)对芦苇和香蒲2种典型湿地植物种子发芽率、发芽速率、芽长和根长的影响,旨在利用芦苇、香蒲等湿地植物以有性繁殖的方式为松花江下游沿江湿地恢复提供技术支持。结果表明:土壤埋深对芦苇、香蒲种子的发芽率和发芽速率均有显著影响,2种植物种子发芽率、发芽速率随土壤埋深增加波动变化;0和25 mm土壤埋深时芦苇种子发芽率较高、发芽速度较快;0和>20 mm土壤埋深时香蒲种子发芽率较高、发芽速度较快;从芽长和根长来看,<10 mm的土壤埋深更利于2种植物存活和生长;相同土壤埋深情况下,芦苇种子较香蒲种子具有更强的萌发能力。  相似文献   
160.
为了分析样方大小对苔藓植物生态指标的影响,在环境相对一致的条件下,在各样点以巢式取样法调查苔藓植物盖度,取样的大小分别为20 cm× 20 cm,30 cm× 30 cm,40 cm×40 cm,50 cm× 50 cm,60 cm×60 cm.通过统计发现,随着取样面积的增加,目测法所获得的优势种、总的苔藓植物的盖度...  相似文献   
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