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1.
《北京城市总体规划(2016—2035)》首次提出需加强三山五园地区整体保护,为推进研究和保护“五园”之中唯一园址不存的畅春园,通过综合研究多件清宫历史图档、近现代航拍测绘影像及考古报告等资料的空间关系,复原畅春园及附属的西花园在乾隆和道光2个时期的平面布局,并初步确定其在海淀区的具体区位,以及位于三山五园地区保护红线之内的事实。在此基础上对两园的功能和景观布局进行了初步探讨,表明畅春园是一座跨越明清两代、艺术水平较高的大型人工山水园,对清代皇家园林的营建产生了重要的影响,因此具有较高的研究价值。  相似文献   
2.
为系统掌握常春二乔玉兰春夏季开花物候节律,探讨其与营养物质的关系,本研究以6年生常春二乔玉兰为试验材料,观测其年生长发育节律、春夏季开花物候特性以及茎段营养物质的含量变化。结果表明:(1)每年12月始至翌年2月下旬为常春二乔玉兰休眠期。2月下旬花芽膨大生长,并于3月开始春季开花,花期持续约20 d。4月进行营养生长,5月完成花芽分化。5月底部分花芽膨大并于6月开始开花,夏季花期持续约20 d。7~9月为未膨大花芽的发育滞缓期。此外,少量夏季开放的花的基部侧芽再次分化形成花芽。10~12月随着落叶的开始,树体逐渐进入休眠期。(2)常春二乔玉兰营养生长后分化的花芽能够花开两季。春季开花为先花后叶,开花率为100%,开花同步率较高,雌、雄蕊发育正常,为可育花。夏季开花为花叶同放,开花率约为30%,且开花同步率较低,开放的花内雌、雄蕊发育异常,为不育花。(3)春季开花期间可溶性糖和可溶性蛋白呈下降趋势,淀粉含量于开花后期下降;夏季开花期间可溶性糖和淀粉总体呈先降后升趋势,而可溶性蛋白总体呈下降趋势。综上所述,常春二乔玉兰春、夏季开花期内开花模式存在一定差异,其显著节律特征与营养物质含量变化有关,推测低水平的可溶性糖及高水平的淀粉和可溶性蛋白有利于春季开花的启动,而低水平的可溶性蛋白及高水平的可溶性糖和淀粉含量则有利于夏季开花的实现。  相似文献   
3.
化疗性静脉炎小鼠模型的建立   总被引:1,自引:0,他引:1  
黄吉春  郭勇  余鸿 《四川动物》2007,26(3):693-696
目的通过静脉注射盖诺(vinorelbine,VNB)为化疗性静脉炎(chemotherapy induced phlebitis,CIP)研究,提供效果稳定的CIP模型。方法49只成年小鼠随机分为6个实验组和1个对照组。实验组小鼠分别从右侧鼠尾静脉注射不同浓度的等体积VNB溶液,对照组则注射等体积生理盐水。注射后第5天对CIP临床表现进行分级评价后处死。制作石蜡切片并进行镜下分级。结果随注射VNB浓度及剂量的增加,小鼠静脉炎发生率也逐渐增高,但浓度剂量过高动物出现中毒死亡。用3.2mg/ml的VNB按38mg/kg注射组CIP发生率达100%,无动物死亡,出现红斑、水肿、条索状改变等典型CIP临床症状和内皮脱落、炎细胞浸润、组织水肿等CIP镜下改变,对照组未出现类似变化。结论本实验通过鼠尾静脉注射VNB成功建立了小鼠CIP模型。  相似文献   
4.
长春市不同土地利用生境土壤螨类群落结构特征   总被引:14,自引:1,他引:14  
2003年7月和9月对长春市郊区天然次生林、农田、防护林和市区公园绿地等典型土地利用生境进行土壤螨类调查,Tullgren法提取土壤螨类,应用个体密度、类群数量、群落多样性、丰富度和均匀度、甲螨群落MGP分析和捕食性螨类MI等指数,研究土壤螨类的群落生态结构特征,了解土地利用差异对土壤螨类群落结构的影响。研究区共捕获土壤螨类3亚目92属8703只,其中隐气门亚目(Cryptostigmata)54属5091只,前气门亚目(Prostigmata)17属1582只,中气门亚目21属2030只。研究结果表明:长春市土地利用差异对土壤螨类群落结构特征影响明显,其中地表凋落物的移除和耕作活动是影响螨类群落结构的主要因素,地表凋落物的移除显著减少螨类群落的类群数、个体密度、群落多样性和丰富度,耕作活动促进螨类个体向土壤剖面下层移动,而地表植物群落类型对土壤螨类群落生态结构特征影响差异不显著。  相似文献   
5.
长春地区出土的髌骨测量   总被引:1,自引:1,他引:0  
杜清太 《人类学学报》1984,3(2):114-117
本文对长春地区出土的140套成人干燥骨骼标本中的177个髌骨、股骨、胫骨进行了测量。  相似文献   
6.
Renal cell carcinoma (RCC) is currently one of the most treatment‐resistant malignancies and affects approximately three in 10,000 people. The impact of this disease produces about 31,000 new cases in the United States per year; and 12,000 people in the United States alone die from RCC annually. Although several treatment strategies have been investigated for RCC, this cancer continues to be a therapeutic challenge. For this reason, the aim of our study is to develop a more effective combinational therapy to treat advanced RCC. We examined the effect of vinorelbine on the signalling pathways of two human renal cancer cell lines (A498 and 786‐O) and also examined the in vivo effect of vinorelbine treatment alone and vinorelbine in combination with the anti‐VEGF antibody 2C3 on A498 and 786‐O tumour growth in nude mice. Tumour angiogenesis was measured by vWF staining, and apoptosis was determined by the TUNEL assay. We observed a significant tumour growth inhibition when using a combinational therapy of anti‐VEGF antibody 2C3 and vinorelbine in both A498 and 786‐O tumour‐bearing mice. The results suggest a breakthrough treatment for advanced RCC.  相似文献   
7.
目的:观察陀螺旋转式立体定向放射治疗系统(陀螺刀)联合长春瑞滨、顺铂(NP)方案治疗局部晚期非小细胞肺癌(NSCLC)的临床疗效观察及毒副反应。方法:94例局部晚期NSCLC患者,先给予陀螺刀治疗,单次治疗剂量3.2-5.0 Gy,等剂量曲线50%-70%,计划靶体积(PTV)覆盖95%以上,总剂量35-50 Gy,治疗后进行NP方案化疗4-6个周期。与同期144例单纯陀螺刀治疗局部晚期NSCLC患者治疗结果相比较。结果:联合治疗的94例患者,近期有效率为86.17%(81/94),6、12和24个月生存率分别为86.17%(81/94)、60.64%(57/94)和36.17%(34/94),毒性反应较轻。同期单纯陀螺刀治疗患者,近期有效率为88.19%(127/144),6、12和24个月生存率分别为87.50%(126/144)、44.44%(64/144)和23.68%(33/144)。结论:陀螺刀联合NP方案是一种对局部晚期NSCLC比较有效的治疗方法,毒副反应较轻。  相似文献   
8.
The characterizations of residue levels and sources of organochlorine pesticides (OCPs) in soils are necessary to evaluate the potential pollution and risks of OCPs to the ecosystems and human health. A total of 51 surface soil samples were collected from peri-urban vegetable fields of Changchun and 13 OCPs were analyzed to learn the composition, spatial distribution and sources. The concentrations were in the ranges of 0.94–107.8 ng g?1 for DDTs, 0.89–98.3 ng g?1 for HCHs, 0.22–18.20 ng g?1 for Chlordanes, nd–4.49 ng g?1 for aldrin and nd–9.66 ng g?1 for dieldrin, respectively. The total OCPs concentrations ranged from 2.44 to 177.1 ng g?1 and the higher residues were mainly distributed in northeast and southwest sites, as well as sites along the Yitong River. According to the concentrations and detection frequencies, DDTs and HCHs were the most dominant compounds. Compositional analysis and principal component analysis suggested that DDT, HCH and chlordane in most soil samples derived from historical application except the slight fresh introduction at some locations. There exist a variety of OCPs residues in peri-urban vegetable soils of Changchun, but it is still safe and suitable for agricultural production for the most part, and some specific locations with high OCPs residues ought to be a cause for concern.  相似文献   
9.
The goal of this study was to assess the antitumor efficacy and safety of lobaplatin-based regimens as the second line of treatment in patients with metastatic breast cancer (MBC) resistant to anthracyclines and taxanes, compared with that of cisplatin-based regimens. During August 2012 to April 2015, 87 patients who received lobaplatin-based regimens or cisplatin-based regimens were included. Medical records of the patients noted that lobaplatin (30?mg/m2) or cisplatin (25?mg/m2), combined with another chemotherapeutic agent such as Gemcitabine (1000?mg/m2) or Vinorelbine (25?mg/m2), was intravenously given to the patients on a basis of twenty-one days as one treatment cycle. All the patients were followed until August 2017. The endpoint of this study was progression-free survival (PFS), overall survival (OS), and estimated objective response rate (RR). Safety and drug tolerability data were also obtained. Lobaplatin-based regimens prolonged PFS compared to cisplatin-based regimens (median 13.2 vs 4.7?months, hazard ratio?=?0.37, 95% confidence intervals: 0.21–0.67, P?=?.0007), while OS was not significantly different between the two groups (hazard ratio?=?0.72, 95% confidence intervals: 0.40–1.30, P?=?.2767), as was objective RR (37.8% vs 33.4%, x2 = 0.19, P?=?.6653). Nausea/vomiting and renal injury were more frequent with cisplatin-based regimens. Our results show that lobaplatin-based regimens are superior to cisplatin in terms of efficacy and are better tolerated.  相似文献   
10.
乳腺癌是较早开始个体化治疗的肿瘤之一。表皮细胞生长因子受体(epidermalgrowthfactorreceptor,EGFR)6~表达与乳腺癌组织学分期、生长速度呈正相关,可作为乳腺癌患者预后的指标之一。临床上,长春瑞滨(Vinorelbine,NVB)~要作为耐药性晚期乳腺癌的挽救性化疗药物,单药治疗亦具有一定疗效。该研究结果发现,乳腺癌组织EGFR表达与NVB的敏感性相关(P=0.001),而与紫杉醇、阿霉素及5.氟尿嘧啶无相关性。EGFRFH性乳腺癌细胞MDA-MB-435s对NVB耐药,而EGFR阳性细胞MCF-7则敏感.但是EGFR中和性抗体会降低敏感性。进一步研究发现,NVB会引起MCF-7表面EGFI滚达上调,以及胞内ERK1/2激酶的磷酸化,且这一效应会被抗EGFR抗体部分抑制。研究结果表明,乳腺癌细胞对NVB的敏感性与膜表面EGFR表达水平相关,提示EGFR可作为NVB治疗敏感性的预测分子。  相似文献   
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