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101.
报道了浙江省发现的2种兰科植物新记录,分别是采集自浙江省台州市黄岩区划岩山的瘤唇卷瓣兰[Bul-bophyllum japonicum(Makino)Makino]与绿花斑叶兰[Goodyera viridiflora(Bl.)Lindley ex D.Dietrich].凭证标本保存于杭州师范大学标本馆(HTC).  相似文献   
102.
浙江江山公益林物种种间关系及CCA排序   总被引:3,自引:0,他引:3  
利用浙江省江山市80个公益林固定小班监测数据,基于生态位理论、种间联结、CCA排序方法对研究区内群落优势种种间关系及其与环境的关系进行研究。结果表明:江山市公益林群落中杉木、檵木、紫萁分别在乔木、灌木、草本层中占优势地位;石栎与青冈、隔药柃与山苍子、蕨与海金沙的生态位重叠指数值分别在乔、灌、草本层中最大;而CCA协变量矩阵偏典范对应分析说明物种分布主要受海拔、坡度、坡向(光照强度)以及腐殖质厚度的影响,总体上可以对89.44%的环境因子进行解释。并且还表明,生态位宽度较大的物种其生态位重叠值较大,并在CCA排序图物种集中区分布。反之,生态位重叠较小,在CCA排序图中将偏离物种集中区;除此之外,在CCA排序图上,物种间的距离与其生态位重叠值的大小及种间联结均有密切的关联,若未存在显著的联结性,随物种间的生态位重叠值越高,其在CCA排序上的距离越近,若存在显著联结性,则正相关缩小距离,负相关拉大距离。  相似文献   
103.
Aging is a worldwide challenge, and it is accompanied by the accumulation of senescent cells. Cellular senescence is traditionally defined as permanent cell growth arrest and currently includes the senescence-associated secretory phenotype (SASP). There are two main types of cellular senescence, including telomere-dependent replicative senescence and stress-induced premature senescence. The process of cellular senescence is mainly controlled by two effector pathways, namely, the p53-p21 and p16-retinoblastoma protein (pRB) pathways. Vascular smooth muscle cells (VSMCs) are integral parts of arteries and play an important role in vascular structure and function. VSMC senescence may be triggered by many factors, such as angiotensin II, oxidative stress, inflammation, DNA damage, and small molecule compounds. These inducers are able to genetically and epigenetically regulate VSMC senescence. The senescence of VSMCs together with the SASP contributes to chronic vascular inflammation, the loss of arterial function, and the development of age-related diseases. Current evidence suggests that the senescence of VSMCs might be harmful to individual health, whereas its influence on the lifespan is not clear. The purpose of this paper was to review the current knowledge regarding VSMC senescence and its relevance to hypertension, atherosclerosis, and diabetes, as well as the potential mechanisms responsible for VSMC senescence in these age-related diseases.  相似文献   
104.
105.
报道浙江省蕨类植物新记录种4个,即膜蕨科的毛蕗蕨Hymenophyllum exsertum Wall. ex Hook.、墨兰瓶蕨Vandenboschia cystoseiroides (Christ) Ching和管苞瓶蕨Vandenboschia kalamocarpa (Hayata) Ebihara,以及鳞毛蕨科的二型肋毛蕨Ctenitis dingnanensis Ching。凭证标本存放于浙江省景宁县林业局标本馆。  相似文献   
106.
OBJECTIVES: To report the long-term outcome and toxicity of locoregionally advanced nasopharyngeal carcinoma (LA NPC) treated with nimotuzumab (h-R3) plus intensity-modulated radiotherapy (IMRT) with or without chemotherapy. METHODS: From May 2008 to March 2014, 3022 newly histology-proven, nonmetastatic NPC patients were retrospectively reviewed; among them, 257 patients treated with h-R3 were enrolled in this study. The patients' age range was between 10 and 76 years. The distribution of patients by disease stage was 150 (58.4%) in stage III, 88 (34.2%) in stage IV A, and 19 (7.4%) in stage IV B. All the patients received the treatment of h-R3 plus IMRT, and from them, 239 cases were also treated with cisplatin-based chemotherapy. Acute and late radiation-related toxicities were graded according to the Acute and Late Radiation Morbidity Scoring Criteria of Radiation Therapy Oncology Group. The accumulated survival was calculated according to the Kaplan-Meier method. Log-rank test was used to compare the survival difference. Multivariate analysis was performed using Cox's proportional-hazard model. RESULTS: All 257 patients had completed combined treatment; 231 patients received h-R3 plus IMRT with induction chemotherapy (IC), while 26 patients received only h-R3 plus IMRT. With a median follow-up of 48 months (range, 13-75 months), the estimated 5-year local recurrence-free survival, regional recurrence-free survival, distant metastases-free survival, progression-free survival, and overall survival (OS) rates were 94.3%, 94.8%, 91.9%, 83.4%, and 86.2%, respectively. Univariate analysis showed that age, T stage, clinical stage, and IC were related with OS. Multivariate analysis indicated that T stage and IC were independent prognostic factors for OS. The incidence of grade 3 to 4 acute mucositis and leukocytopenia was 10.9% and 19.8%, respectively, with no cases of skin rash and infusion reaction. Xerostomia was the most common late complication, and the degree of dry mouth in most survivors was mild to moderate at the last follow-up time. CONCLUSION: h-R3 plus IMRT with or without chemotherapy showed promising outcomes in terms of locoregional control and survival without increasing the incidence of radiation-related toxicities for patients.  相似文献   
107.
植物种群格局与不同生活型之间物种共存的研究有助于理解物种的生态适应性。丘间低地是科尔沁沙地生态系统发育的一个关键阶段,在此生境中存在多种生活型的植物。采用样线法调查了科尔沁沙地丘间低地100个1 m×1 m样方,根据调查结果选取了分属于4个科3个生活型的15种植物为对象进行格局和共存机制的研究。经格局指数以及Poisson分布的t检验和χ2检验表明:15个物种的种群分布均为聚集分布,但聚集强度差别很大,这可能由种子扩散、物种形态、植物发育时期以及土壤养分条件差异导致;聚集指数DI、CI、m*、GI之间呈极显著正相关关系,表明它们表征共同的生态学意义,相互之间可以替代;多年生草本这一生活型内的物种相互共存较多,多年生草本与其他两个生活型共存较少,这可能与相同生活型物种生态位重叠度大有关。Spearman秩相关和Pearson相关对物种对的检验结果均表明:部分豆科植物与其他科的多年生草本共存机会较大,这可能与豆科植物对改良土壤和减少病虫害有关。物种聚集分布以及不同生活型内几个物种对正相关显著是物种适应环境的结果,对结果显著的部分植物进一步研究可以为沙地植被恢复提供理论指导。  相似文献   
108.
Aims The concentration of CO2 and other greenhouse gases in the atmosphere has considerably increased over last century and is set to rise further. Forest ecosystems play a key role in reducing CO2 concentration in the atmosphere and mitigating global climate change. Our objective is to understand carbon storage and its distribution in forest ecosystems in Zhejiang Province, China. Methods By using the 8th forest resource inventory data and 2011 2012 field investigation data, we estimated carbon storage, density and its distribution in forest ecosystems of Zhejiang Province. Important findings The carbon storage of forest ecosystems in Zhejiang Province was 602.73 Tg, of which 122.88 Tg in tree layer, 16.73 Tg in shrub-herb layer, 11.36 Tg in litter layer and 451.76 Tg in soil layer accounting for 20.39%, 2.78%, 1.88% and 74.95% of the total carbon storage, respectively. The carbon storage of mixed broadleaved forests was 138.03 Tg which ranked the largest (22.90%) among all forest types. The young and middle aged forests which accounted for 70.66% of the total carbon storage were the main body of carbon storage in Zhejiang Province. The carbon density of forest ecosystems in Zhejiang Province was 120.80 t•hm2 and that in tree layer, shrub-herb layer, litter layer and soil layer were 24.65 t•hm2, 3.36 t•hm2, 2.28 t•hm2 and 90.51 t•hm2, respectively. The significant relationship between soil organic carbon storage and forest ecosystem carbon storage indicated that soil carbon played an important role in shaping forest ecosystem carbon density. Carbon density of tree layer increased with age in natural forests, but decreased in the order over-mature > near-mature > mature > middle-aged > young forest in plantations. The proportions of young and middle aged forests were larger than any other age classes. Thereby, the carbon storage of forest ecosystems in Zhejiang Province could be increased through a proper forest management.  相似文献   
109.
2021年9月13日在浙江德清莫干山(30°36′27″N,119°51′39″E,海拔601 m)采集到1只刺猬标本。该标本耳较短,不超过周围棘刺长。体背棘刺短细,几无全白色棘刺,大部分棘刺从基部至刺尖分为4段:第1段白色,长度占棘刺长2/3以上;第2段黑色或深褐色,约3~5 mm;第3段白色,约1~3 mm;第4段,即棘刺尖端,黑色或深褐色。头骨吻部较短,鼻骨狭长;整个额部较为平直;矢状脊不发达,但明显可见;人字脊发达。这些特征与侯氏猬(Mesechinushughi)的鉴别特征基本一致。基于Cytb全序列构建的最大似然树显示,该标本与安徽的侯氏猬聚为一支(支持率100%),该支又与陕西的侯氏猬聚为一支(支持率97%),并构成单系群。该标本Cytb全序列与安徽的侯氏猬遗传距离为0.35%,与陕西的侯氏猬遗传距离为4.92%~5.27%。基于以上结果,确定该标本为侯氏猬。这是林猬属侯氏猬在浙江省的首次记录,也是继安徽发现侯氏猬以来,再次在长江以南发现侯氏猬的新分布点。根据已获取的信息,浙江的侯氏猬在浙西丘陵山区分布较广,主要栖息在林地生境,与东北刺猬(Erinaceus amuren...  相似文献   
110.
浙江常山黄泥塘全球层型剖面的中奥陶世疑源类   总被引:4,自引:0,他引:4  
尹磊明 《古生物学报》2003,42(1):89-103
浙江常山黄泥塘剖面在1996-1997年被国际奥陶系分会和国际地质科学联合会(IUGS)确立为全球中奥陶统达瑞威尔阶(Dariwillian)层型剖面,从该剖面宁国组Azygograptus suectcus-Exigraptus clavus笔石带至Undulograptus sinicus笔石亚带下部的页岩及灰岩中获得丰富的,保存不很好的疑源类化石,它们包含26个形态属,41个已知种和12个未定名种.该宁国组疑源类组合极少有环冈瓦纳古陆的“冷水“类型,根据疑源类类型在地层柱的首次出现,可划分两个与Azygograptus suecicus和Undulograptus austrodentatus笔石带相吻合的疑源类生物地层单元,结合中国南方在奥陶纪的古地理位置加以讨论,当前疑源类组合表明,中奥陶世环冈瓦纳古陆的“冷水“洋流至下扬子区已很微弱.  相似文献   
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