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1.
Castleman disease (CD) is a rare and heterogeneous disorder characterized by lymphadenopathy that may occur in a single lymph node (unicentric) or multiple lymph nodes (multicentric), the latter typically occurring secondary to excessive proinflammatory hypercytokinemia. While a cohort of multicentric Castleman disease (MCD) cases are caused by Human Herpes Virus-8 (HHV-8), the etiology of HHV-8 negative, idiopathic MCD (iMCD), remains unknown. Breakthroughs in “omics” technologies that have facilitated the development of precision medicine hold promise for elucidating disease pathogenesis and identifying novel therapies for iMCD. However, in order to leverage precision medicine approaches in rare diseases like CD, stakeholders need to overcome several challenges. To address these challenges, the Castleman Disease Collaborative Network (CDCN) was founded in 2012. In the past 3 years, the CDCN has worked to transform the understanding of the pathogenesis of CD, funded and initiated genomics and proteomics research, and united international experts in a collaborative effort to accelerate progress for CD patients. The CDCN’s collaborative structure leverages the tools of precision medicine and serves as a model for both scientific discovery and advancing patient care.  相似文献   

2.
C. Lobo, S. Amin, A. Ramsay, T. Diss and G. Kocjan Serous fluid cytology of multicentric Castleman’s disease and other lymphoproliferative disorders associated with Kaposi sarcoma‐associated herpes virus: a review with case reports Objective: The aim of this study is to describe and review the cytological features of Kaposi sarcoma‐associated herpes virus (KSHV) related entities, such as multicentric Castleman’s disease (MCD), plasmablastic‐lymphoma (PBL) and primary effusion lymphoma (PEL), which all may present as body cavity effusions. Serous fluid cytology of MCD and PBL has not, to our knowledge, thus far been described. Although different in nature, MCD, PBL and PEL are characterized by similar morphological features. Materials and methods: Body cavity effusions from four different patients with previously known or unknown KSHV‐related lymphoproliferations have been examined by routine cytology, immunocytochemistry (IC) and polymerase chain reaction (PCR). Results: MCD, PBL and PEL are all characterized by increased cellularity, comprising mainly lymphoid and plasmacytoid cells with variable proportions of immunoblasts. Immunocytochemistry and PCR results show the MCD to be CD138 and KSHV positive, CD30 negative, IgM, IgH and lambda restricted but IgH polyclonal. PBL was CD138 positive, kappa restricted, weakly positive with VS38 and over 80% positive with MIB 1. PEL was CD45, EMA, CD138, KSHV, p53 and CD3 positive, CD20, EBV, CD30, CD2, CD4, ALK1, epithelial and mesothelial markers negative, and PCR monoclonal B‐cell expanded (Ig‐kappa bands). Conclusion: Cytological examination of effusions in KSHV‐related lymphoproliferative disorders may show similar morphological features but clonality studies and immunocytochemistry are very helpful in distinguishing between these rare benign and malignant lymphoproliferative diseases.  相似文献   

3.
We investigated whether estrogenic recruitment could enhance the antitumor effect of chemotherapy in 165 patients with advanced breast cancer, presumably sensitive to hormonal treatments (ER + and/or PgR + lesions). The therapeutic regimen consisted of: (a) estrogenic suppression by aminoglutethimide 1 g/day + hydrocortisone 40 mg/day; surgical castration in premenopausal patients only; (b) FAC (5FU 500 mg/m2; ADM 50 mg/m2; CPA 500 mg/m2) for 3 weeks; (c) following randomization, exactly 24h prior to chemotherapy, patients had to take 1 tablet of either placebo (PL) or 50 μg ethinylestradiol (EE2). Tolerance, responses, time to progression and median survival were identical in both groups. Thus, EE2 before chemotherapy did not contribute to the efficacy of this particular therapeutic regimen, which yielded an overall response rate of 64%. We conclude that the validity of the hormonal recruitment concept has not yet been established in clinical practice, so that this approach remains experimental.  相似文献   

4.
通过去除法控制竹丛密度,人为设置4种竹丛密度梯度[密度1:(3.83±0.53)株/m~2;密度2:(16±1.80)株/m~2;密度3:(39±1.69)株/m~2;密度4:(69±2.15)株/m~2],测定不同密度竹丛下的微环境(包括土壤温度、湿度、电导率、凋落物厚度),研究竹丛密度及微环境对雷公鹅耳枥(Carpinus viminea Wall.)幼苗数量、存活动态、生长情况的影响。结果显示,竹丛密度对环境有显著影响,随着竹丛密度的增加,竹丛盖度、凋落物厚度、土壤温度升高明显;雷公鹅耳枥幼苗萌生量显著减少,4组密度梯度中幼苗数量分布依次排序为:密度1(28.53±3.14)株/m~2密度2(17.36±1.45)株/m~2密度3(12.36±0.93)株/m~2密度4(8.92±0.93)株/m~2,表明随着小径竹密度增加,其对雷公鹅耳枥幼苗萌发的抑制作用越强;小径竹的密集生长可对雷公鹅耳枥幼苗的存活率产生影响,且对幼苗的生长具有一定抑制作用。研究结果表明小径竹密集生长的环境不仅抑制了雷公鹅耳枥新生幼苗的分布和幼苗生长,还对种群的更新以及森林群落的演替产生一定的负面影响。  相似文献   

5.
目的: 探讨恶性血液病外周血淋巴细胞亚群变化特征及临床意义。方法: 采用流式细胞仪检测64例初诊的血液系统恶性肿瘤患者的外周血淋巴细胞亚群。病种包括急性髓系白血病(acute myeloid leukemia,AML)、急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)、霍奇金淋巴瘤(Hodgkin’s lymphoma,HL)、非霍奇金淋巴瘤(Non-Hodgkinlymphoma,NHL)。分析比较30例正常人的外周血淋巴细胞亚群与实验组的差异,并对64例恶性血液病患者中连续动态监测的21例急性白血病患者外周血淋巴细胞亚群结果变化与预后关系进行分析。结果: 不同成人恶性血液病患者年龄分组淋巴细胞亚群变化无明显差异;恶性血液病患者中CD3 +CD8 + T淋巴细胞百分比、Treg细胞百分比均增加;CD16 +/CD56 +NK细胞百分比及CD4 +/CD8 +比值均下降;CD3 +T淋巴细胞数量、CD3 +CD4 +淋巴细胞数、CD3 +CD8 +淋巴细胞数量、CD3 -CD19 +淋巴细胞数量、CD16 +/CD56 +NK淋巴细胞数量及CD4 +/CD8 +比值均减少;急性白血病及恶性淋巴瘤患者外周血淋巴细胞亚群与正常对照组比较存在一定的差异;急性白血病未缓解组的Treg细胞比例明显高于急性白血病首疗程缓解组及对照组;急性白血病复发组Treg细胞比例明显高于急性白血病持续缓解组以及对照组;对21例急性白血病患者动态监测的淋巴细胞亚群发现,化疗缓解的患者Treg在化疗过程中逐渐下降,至第3~6个疗程逐渐接近正常对照,化疗未缓解的患者Treg细胞在化疗过程中逐渐上升或持续大于10%,明显高于完全缓解组,复发患者Treg在化疗过程中先下降后明显上升。 结论: 恶性血液病患者免疫功能显著低于健康人,且伴随免疫功能紊乱,且不同疾病类型、不同的疾病状态免疫紊乱的程度不一,Treg细胞比例可以用来预测急性白血病患者疗效及复发,可以为患者的临床治疗方案及用药强度提供指导依据。  相似文献   

6.
周扬  张丹桔  宋思梦  李勋  张艳  张健 《植物研究》2017,37(6):915-925
林窗大小与植物计量化学的耦合关系是林分管理的基础,马尾松人工林相关研究尚欠缺。本文以宜宾高县来复镇41 a生马尾松(Pinus massoniana)人工林为研究对象,设置8个梯度不同大小林窗(CK:0 m2、G1:100 m2、G2:225 m2、G3:400 m2、G4:625 m2、G5:900 m2、G6:1 225 m2、G7:1 600 m2),通过调查,选取自然更新优势草本铁芒萁(Dicranopteris dichotoma)、芒(Miscanthus sinensis)和皱叶狗尾草(Setaria plicata)进行叶片N,P生态化学计量特征探究。结果发现:研究区优势草本叶片平均N含量为15.25 mg·g-1,P含量为1.19 mg·g-1,更新植物受限元素主要为N元素;随林窗面积增大,林内光照强度、温度和湿度均显著增加,优势草本叶片N、P含量受林窗大小显著影响,各物种P含量随林窗面积增大呈降低趋势;不同物种N含量随林窗大小改变的变化规律不同,芒萁N含量随林窗面积增大而显著下降,芒和皱叶狗尾草随林窗面积增大N含量显著增加;在叶片N、P化学计量水平上,芒萁的最适林窗面积为100~225 m2,芒和皱叶狗尾草最适林窗面积为1 225~1 600 m2。上述结果说明通过调整林窗来进行近自然改造和森林抚育等措施,能够促进人工林内养分循环,有利于提高马尾松人工林生态系统生产力。  相似文献   

7.
生物过滤法处理城市污水处理厂臭气   总被引:12,自引:0,他引:12  
对某城市污水处理厂沉砂池的臭气进行了生物过滤处理。生物过滤池滤料层高1.5m,滤料体积55m3,臭气处理量为12000m3·h-1。对除臭效果120d的监测和研究结果表明,进气中H2S浓度在1.96~4.63mg·m-3之间,NH3的浓度为2.21~5.68mg·m-3。处理后,出气中H2S的浓度在0.03~0.97mg·m-3间,去除率均达80%以上,NH3浓度最高值仅为0.46mg·m-3,低于1.0mg·m-3的一级排放标准。生物除臭复合微生物主要包括细菌、酵母和霉菌,其中细菌含量最高,每克干滤料细菌含量达1.8~3.1×108CFU。菌种鉴定结果表明,除臭菌主要有芽孢杆菌属(Bacillus)、假单胞菌属(Pseudomonas)、动胶菌属(Zoogloea)、不动杆菌属(Acinetobacter)、硫杆菌属(Thiobacillus)、酵母属(Saceharomyces)、假丝酵母属(Candida)、曲霉属(Aspergillus)、青霉属(Penicillium)、根霉属(Rhizopus)等种属的微生物。  相似文献   

8.
This study was designed to assess the tolerability of chronomodulated infusion chemotherapy, individualized by the rhythm of peripheral blood cells. Twenty patients with metastatic gastric cancer were randomized to chronotherapy or day-time arms of 5-fluorouracil (FU) (600 mg/m2, 8 h inf.d1-5) and folinic acid (FA) (20 mg/m2, iv, d1-5) in the first cycle and crossed-over to the other arm in the following cycles. Ten of 18 evaluable patients were assigned to chronotherapy arm and eight to day-time in the first cycle. Although there was no significant difference between two arms on enrollment, chronotherapy arm yielded an improvement of 45% of QLQ-C30 scores (p = 0.021) and the day-time arm had 11% improvement (p = 0.575). After the crossing-over, chronotherapy arm, again, had a significant improvement in QLQ-C30 scores, compared to the day-time arm (14% vs. -18%, p = 0.001, respectively). Mucositis/diarrhea was significantly higher in the day-time arm compared to chronotherapy arm (p = 0.015). In conclusion, chronomodulated infusion of 5-FU might improve the quality of life.  相似文献   

9.
在新疆北部地区自然生态条件下,采用棉花品种‘新陆早45号’为试验材料,设置5种滴灌定额处理(W1:600 m3·hm-2,W2:540 m3·hm-2,W3:480 m3·hm-2,W4:420 m3·hm-2,W5:360 m3·hm-2),研究了棉花叶面积指数、冠层开度、群体光吸收率、群体光合速率和产量对不同滴灌定额的响应.结果表明: 随着滴灌定额减少,棉花叶面积指数、群体光吸收率、群体光合速率均呈现降低趋势,其中W1与W2处理间的上述参数在盛蕾期至吐絮期均无显著差异;冠层开度则随滴灌定额减少呈增加的趋势.籽棉产量和皮棉产量均以W1处理最高,分别为6549和2677 kg·hm-2;W2处理籽棉产量仅比W1处理低6.5%,灌溉水利用效率较W1处理高3.9%.相关分析表明,盛花期至盛铃期叶面积指数、群体光吸收率和群体光合速率均与籽棉产量呈显著或极显著正相关.因此,控制滴灌定额在540 m3·hm-2有利于棉花在盛花至盛铃期保持较高的叶面积指数、增加冠层开度、保证光吸收率,进而增强群体光合速率,在不显著降低产量前提下提高灌溉水利用效率.  相似文献   

10.
s Kaposi's sarcoma-associated herpesvirus (KSHV) was first identified as the etiologic agent of Kaposi's sarcoma (KS) in 1994.KSHV infection is necessary,but not sufficient for the development of Kaposi sarcoma (KS),primary effusion lymphoma (PEL),and multicentric Castleman disease (MCD).Advances in the prevention and treatment of KSHV-associated Diseases have been achieved,even though current treatment options are ineffective,or toxic to many affected persons.The identification of new targets for potential future therapies and the randomized trial to evaluate the efficacy of new antivirals are required.  相似文献   

11.
为研究风车草(Cyperus alternifolius)和香根草(Vetiveria zizanioides)迁移养分的能力,建立17.0m2风车草潜流式人工湿地和13.3 m2香根草潜流式人工湿地处理猪场废水,在四个季节末测定植物生物量和组织氮、磷、铜、锌含量.结果表明,香根草地下部生物量大于风车草,地上部生物量则是风车草大于香根草.风车草年地上部收获量为3406.47 g·m-2,比香根草的1483.88 g·m-2高2.3倍;风车草的氮含量为22.69 mg·g-1,比香根草的15.44 mg·g-1高7.25 mg·g-1;风车草的磷含量为6.09 mg·g-1,比香根草的5.47 mg·g-1高0.62 mg·g-1.植株含铜、锌量风车草略比香根草高.风车草每年迁移N 68.72 g·m-2和P18.49 g·m-2,香根草迁移N 8.93 g·m-2和P 3.69 g·m-2.风车草人工湿地每年由植物迁移的氮、磷、铜、锌比香根草高4~7倍.  相似文献   

12.
Following the demonstration in 1994, that Kaposi's sarcoma (KS) was associated with a novel virus (KSHV or HHV-8) belonging to the lymphotropic herpes family, this virus was also found in certain lymphoid neoplasias of immunodeficient (HIV+) and immune competent hosts. The association of HHV-8/KSHV infection is now well established with primary effusion lymphoma (PEL) or body cavity based lymphoma (BCBL) and multicentric Castleman's disease (MCD) of the plasma cell type. A possible pathogenic role of HHV-8/KSHV in other lymphoid tumours including primary central nervous system lymphoma (PCNSL) and multiple myeloma (MM) as well as some atypical lymphoproliferations and sarcoidosis has also been suggested, but this is at present a controversial matter, or not confirmed. SeveralHHV-8/KSHV genes, including potential oncogenes, genes homologous to various cellular genes and growth factors have been incriminated in the pathogenesis of KS and PEL/BCBL, but a common pathogenic mechanism for the clearly diverse proliferations represented by PEL, MCD and KS is at present not evident.  相似文献   

13.
周伟  王丹丽  林勉  徐善良  邹秀 《生态科学》2013,32(4):500-508
根据2009年秋~2010年夏每季采样调查,分析和研究了浙江省宁波港海区浮游动物种类组成和数量分布的四季变化特征。结果表明: 经鉴定浮游动物共有70种,隶属3门35属。其中桡足类的种类最多,占总种数的73.54%; 优势种主要有中华异水蚤、矩形龟甲轮虫、伪长腹剑水蚤、挪威小星猛水蚤、小星猛水蚤属、驼背隆哲水蚤、短角长腹剑水蚤等。浮游动物群体丰度呈现出夏季>秋季>春季>冬季的现象,四季平均丰度分别为2.50×103 ind/m3、40.16×103 ind/m3、3.72×103 ind/m3、1.20×103 ind /m3。生物量呈现出夏季>春季>秋季>冬季的现象,四季平均生物量分别为88.94 mg/m3、931.22 mg/m3、58.74 mg/m3、24.49 mg/m3。与历史资料以及邻近海域比较发现,浮游动物丰度和生物量小于或接近于东海各海域。生物多样性分析显示,夏季与春秋冬三季生物多样性(H')有显著性差异(P<0.05),夏季具有较高的生物多样性,Shannon-Wiener多样性指数(H')、种类丰富度(D)、Pielou均匀度指数(J)、最大多样性指数(H'max)基本呈现出夏季>春季>秋季>冬季。与邻近海域相比,多样性指数(H')、种类丰富度(D)、最大多样性指数(H'max)呈下降趋势。  相似文献   

14.
【目的】本研究旨在了解桑螟Diaphania pyloalis幼虫不同饲养密度对其生长发育和繁殖的影响。【方法】本研究测定了室内同一条件下5个幼虫密度(130, 650, 1 300, 1 950和2 600头/m2)下桑螟生长发育和繁殖指标,包括发育历期、幼虫存活率、化蛹率、成虫羽化率、蛹重、产卵期、单雌产卵量等。【结果】幼虫密度对桑螟的生长发育和繁殖均产生不同程度影响,幼虫密度偏低或偏高都不利于桑螟生长发育和繁殖。其中以1 300和1 950头/m2 2种幼虫密度下的桑螟幼虫生长发育和成虫繁殖状态均最佳且两密度下各项指标无明显差异,1 300头/m2密度下,桑螟的幼虫历期、蛹历期和成虫历期分别为11.32, 6.33和5.31 d; 1 950头/m2密度下,桑螟的幼虫历期、蛹历期和成虫历期分别为11.50, 6.00和5.47 d。1 300头/m2幼虫密度下,桑螟化蛹率、成虫羽化率和幼虫存活率分别为86.67%, 100%和86.67%, 1 950头/m2<...  相似文献   

15.
探究siRNA敲减沉默信息调节因子2(SIRT2)对1-甲基-4-苯基吡啶离子(MPP+)诱导的帕金森病细胞模型细胞损伤的影响和机制。CCK-8法检测不同浓度MPP+处理对体外培养小鼠海马神经元HT-22细胞生存率的影响。将细胞分为对照组、MPP+最佳浓度处理组(1 mmol/L MPP+处理组)、阴性转染组(对照组基础上转染SIRT2阴性序列)、SIRT2 siRNA处理组(损伤组基础上转染SIRT2 siRNA)。观察各组细胞凋亡情况,检测凋亡相关蛋白(Bcl-2、Bax、Caspase-9)、线粒体分裂及融合相关蛋白(Drp1、Fis1、OPA1、Mfn1、Mfn2)。与对照组相比,MPP+处理组细胞抑制率均升高,细胞抑制率随MPP+浓度增加而逐渐增加(P<0.05)。与SIRT2 siRNA转染组相比,损伤组Bax、Caspase-9、Drp1、Fis1蛋白表达和细胞凋亡率升高,Bcl-2、Mfn1、Mfn2蛋白表达降低(P<0.05)。SIRT2在MPP+诱导帕金森病细胞模型中表达升高,抑制SIRT2可减轻MPP+诱导帕金森病细胞模型中细胞凋亡并促进线粒体融合,从而对神经元具有一定的保护作用。  相似文献   

16.
The rate of Hg2+-assisted chloride release from several mer-[CrCl(diamine)(triamine)]2+ complexes has been measured as a function of pressure, Hg2+ concentration and temperature. The calculated activation volumes are independent of [Hg2+] and temperature and kinetic parametes 104 kHg (25 °c) (M−1 s−1), ΔH (kJ mol−1), ΔS (J K−1 mol−1), ΔV (cc mol−1) are: (en)(dpt): 6.44. 75.5, −52, −5.0; (ibn)(dpt): 5.81, 89.5, −6, −0.03; (Me2tn)(dpt): 22.2, 84.9, −11, −0.5; (tn)(dpt): 29.1, 87, −1, +0.3; (en)(2,3-tri): 1.94, 87.0, −24, −5.7; (en)(Medpt): 0.417, 94.6, −11, −0.8; (tn)(Medpt): 9.14, 98.3, +26, +1.8.  相似文献   

17.
《植物生态学报》2015,39(8):785
Aims The objective of the study was to evaluate the dynamics of recalcitrant components during foliar litter decomposition at different forest gap size in Pinus massoniana plantation in the low hilly land, Sichuan basin. Methods The experiment was set up by thinning P. massoniana plantation to establish seven different gap sizes (G1: 100 m2, G2: 225 m2, G3: 400 m2, G4: 625 m2, G5: 900 m2, G6: 1225 m2, G7: 1600 m2). The contents of four recalcitrant components (condensed tannins, total phenol, lignin, cellulose) in foliar litter of two native species (Cinnamomum camphora and Toona ciliata) placed in litterbags at different locations in the forest gaps were evaluated. The litterbags placed under closed canopy were used as the control. Litterbags with air-dried leaves of C. camphora and T. ciliata were placed at center, edge of the gap and under the closed canopy in November 2013, and collected in December 2013, February 2014, May 2014 and August of 2014 for lab analysis. Important findings The results showed that: 1) Forest gap size had significant effect on the content of condensed tannins, total phenol and lignin for T. ciliata in gap center. However, the forest gap size had no significant effect on the content of recalcitrant components in the litters of C. camphora and cellulose content of T. ciliata. With the increase of gap size, except for cellulose content, the other three recalcitrant components content in small and medium sized gaps (G1-G5) were significant lower than in large gaps (G6, G7). 2) The condensed tannis content of T. ciliata at the gap center were significant lower than at the gap edge. The lignin contents at gap center of G3 was significant reduced in the C. camphora litter. The condensed tannins, total phenol, and lignin contents of T. ciliata litter in small and medium gaps significantly decreased. 3) The contents of the four recalcitrant components in both species’ foliar litter changed with time. The contents of condensed tannins and cellulose decreased and the content of lignin increased significantly with time, however, the total phenol content increased initially, and then decreased. Therefore, small and medium sized gaps (100-900 m2) could be the optimal gap sizes to promote the degradation of litter recalcitrant components for two native species in P. massoniana plantations.  相似文献   

18.
【目的】本研究旨在明确氰氟虫腙对草地贪夜蛾Spodoptera frugiperda幼虫的毒力水平和田间防治效果,为科学使用氰氟虫腙防治草地贪夜蛾提供参考依据。【方法】采用饲料混毒法在室内测定了氰氟虫腙与4种常用杀虫剂甲维盐、氯虫苯甲酰胺、虱螨脲和茚虫威对草地贪夜蛾3和6龄幼虫的致死中浓度(LC50)及LC90值,以及LC90浓度的这些杀虫剂对3龄幼虫的致死中时(medium lethal time, LT50)值。采用人工喷雾方法测定了玉米田中22%氰氟虫腙悬浮剂(6.6 g/667 m2)、22%氰氟虫腙悬浮剂(17.6 g/667 m2)、5.7%甲维盐水分散剂(1 g/667 m2)和150 g/L茚虫威悬浮剂(2 g/667 m2)对草地贪夜蛾幼虫的防效。【结果】室内生测结果显示,供试的5种杀虫剂中氰氟虫腙对草地贪夜蛾3和6龄幼虫均具有较高的毒力,其LC50值分别为2.64和4.3...  相似文献   

19.
林窗通过改变森林微环境及土壤环境而影响凋落物难降解物质的降解, 目前关于人工林林窗对凋落物分解过程中难降解物质影响的研究较少。该文采用凋落物分解袋法, 以马尾松(Pinus massoniana)人工林人工砍伐形成的7个不同面积的林窗(G1: 100 m2、G2: 225 m2、G3: 400 m2、G4: 625 m2、G5: 900 m2、G6: 1225 m2、G7: 1600 m2)为研究对象, 以林下为对照, 研究了林窗大小对两种乡土树种——樟(Cinnamomum camphora)和红椿(Toona ciliata)凋落叶分解过程中难降解物质(木质素、纤维素、总酚、缩合单宁)含量的影响。结果表明: 1)林窗大小对林窗中心红椿凋落叶缩合单宁、总酚、木质素的含量有显著影响, 对其纤维素含量和樟凋落叶中4种难降解物质含量均无显著影响。随着林窗面积的增大, 红椿凋落叶中除纤维素含量外的其余3种难降解物质含量, 中小型林窗(G1-G5, G1: 100 m2, G2: 225 m2, G3:400 m2, G4: 625 m2, G5: 900 m2)低于大型林窗(G6、G7, G6: 1225 m2, G7: 1600 m2)。2)林窗不同位置, 只有红椿凋落叶中缩合单宁含量林窗中心显著低于边缘, 其余难降解物质含量和樟凋落叶中4种难降解物质含量均无显著差异。樟凋落叶的木质素含量在G3林窗显著低于林下; 红椿凋落叶除纤维素含量外的其余难降解物质含量, 中小型林窗从林窗中心到边缘均显著低于林下。3)随着分解时间的延长, 两种凋落叶都表现出缩合单宁、纤维素含量降低, 木质素含量升高, 总酚含量先升高后降低的变化趋势。研究结果表明: 中小型林窗(100-900 m2)较大面积林窗干扰更有利于凋落叶中难降解物质的降解, 而林窗内的环境异质性应该是凋落物中难分解物质分解动态的主要调控因子, 并且这种效应依赖于初始凋落物质量。  相似文献   

20.
The intent of the proposed system was to develop an in situ biotreatment system for swine manure that should involved minimum handling by the farmer. A demonstration plant has been installed in the Paris region. The intensive lagooning system consists of algal ponds, daphnid ponds and a polishing fish pond working in series with a total area of 2100 m2 and a total volume of 3600 m3.

The performance of the system was evaluated under winter conditions with raw decanted swine manure by measuring N-NH4+ and P-PO43− removal, pH, temperature, water oxygen, algal biomass and daphnid productions.

Results showed that low temperatures (<5°C) did not allow any significant biomass production (0·41–0·68 g dry mass/m2 d). Ammonia-nitrogen, mostly stripped (98% lost by stripping), and phosphate removals were small. However, as soon as the temperature increased in spring (March), ammonia-nitrogen removal was improved with a large contribution (71%) due to stripping and the algal productivity increased to ≈ 3·5 g dry mass/m2 d; CO2 appeared to be a limiting factor.

Ammonia-nitrogen, nitrate, nitrite and orthophosphate showed marked variations that could be correlated with manure overdoses.  相似文献   


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