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早熟甜油蟠桃新品种——‘新月’的选育 被引量:3
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作者 林云弟 韩霞 +4 位作者 赵庆柱 张东起 高静 邱玉宾 赵婧杰 《果树学报》 CAS CSCD 北大核心 2013年第6期1089-1090,F0002,共3页
‘新月’是由‘燕蟠’בAT163’杂交培育出的早熟甜油蟠桃新品种。果实发育期78 d左右。花蔷薇型,花粉多,自花结实。果实扁平形,平均单果质量111 g。果皮底色白色,90%以上果面着鲜红色,果肉白色,质地细脆,可溶性固形物含量14.4%... ‘新月’是由‘燕蟠’בAT163’杂交培育出的早熟甜油蟠桃新品种。果实发育期78 d左右。花蔷薇型,花粉多,自花结实。果实扁平形,平均单果质量111 g。果皮底色白色,90%以上果面着鲜红色,果肉白色,质地细脆,可溶性固形物含量14.4%。耐贮运,抗裂果,不易流胶。 展开更多
关键词 油蟠桃 新品种 '新月’ 早熟
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评《〈新月〉的态度》 被引量:2
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作者 廖超慧 《华中科技大学学报(社会科学版)》 2002年第6期F003-F003,共1页
关键词 《<新月>的态度》 '新月' 文艺思想
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油蟠桃果实发育规律与品质相关因子变化研究 被引量:1
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作者 林云弟 高静 +5 位作者 韩霞 赵庆柱 杨志莹 李田 邱玉宾 赵婧杰 《中国农学通报》 2016年第7期69-73,共5页
为研究油蟠桃果实生长发育规律以及主要品质指标的形成和变化规律,以‘紫月’、‘新月’、‘美月’油蟠桃为试材,对果实发育过程中纵横径、单果重、可溶性总糖、可滴定酸、淀粉含量和落果进行研究。结果表明:‘紫月’、‘新月’、‘美... 为研究油蟠桃果实生长发育规律以及主要品质指标的形成和变化规律,以‘紫月’、‘新月’、‘美月’油蟠桃为试材,对果实发育过程中纵横径、单果重、可溶性总糖、可滴定酸、淀粉含量和落果进行研究。结果表明:‘紫月’、‘新月’、‘美月’果实发育规律基本符合核果类果实双"S"型曲线。随着果实的生长发育,‘新月’、‘美月’可溶性总糖含量变化呈逐步上升趋势,可滴定酸变化呈先升后降趋势,果实淀粉含量呈递减趋势。落果波相观察‘美月’有3次落果高峰;‘紫月’、‘新月’分别有2次落果高峰,且第1次落果期时间较长,可能与‘紫月’、‘新月’果实发育期比‘美月’短有关。总体看来,油蟠桃果实生长发育规律以及主要品质相关因子的变化规律与普通桃、油桃相似。 展开更多
关键词 油蟠桃 果实发育 品质 '紫月’ '新月’ '美月’
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New details indicated by different stainings during conjugation of ciliated protozoa Paramecium 被引量:2
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作者 高欣 杨仙玉 +3 位作者 朱嘉骏 袁进强 王逸雯 宋敏国 《Zoological Research》 CAS CSCD 北大核心 2011年第6期651-656,共6页
During conjugation of Paramecium caudatum, nuclear events occur in a scheduled program. Morphological studies on nuclear behavior during conjugation of P. caudatum have been performed since the end of the 19th century... During conjugation of Paramecium caudatum, nuclear events occur in a scheduled program. Morphological studies on nuclear behavior during conjugation of P. caudatum have been performed since the end of the 19th century. Here we report on new details concerning the conjugation of P. caudatum through the staining of conjugating ceils with protargol, carbol fuchsin solution, Hoechst 33342 and immunofluorescence labeling with monoclonal antibody of anti-a tubulin. 1) The crescent nucleus is a characteristic of the meiotic prophase of P. caudatum, has an unstained area. We stained this area with protargol, which was separated from the chromatin area and was not detected by the other stainings. 2) In regards to the four meiotic products, it has long been considered that only one product enters the paroral cone region (PC) and survives after meiosis. However, our protargol and immunofluorescence labeling results indicated that PC entrance of the meiotic product happened before the completion of meiosis instead of after. 3) In our previous study, protargol staining indicated the presence of a swollen structure around the central part of the "U" and "V" shaped spindles connecting the two types of prospective pronuclei. However, immunofluorescence labeling with anti-a tubulin antibodies gave a different image from protargol. All these observations form the basis for further studies of their molecular mechanisms. 展开更多
关键词 PARAMECIUM CONJUGATION CRESCENT PC entrance Connecting spindles
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ACUPOINT-LIKE STRUCTURE AND MERIDIAN-LIKE DISTRIBUTION ON THE BODY SURFACE OF PLATYFISH 被引量:1
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作者 李继伟 晋志高 +1 位作者 张璐 蒋瑾 《World Journal of Acupuncture-Moxibustion》 2008年第1期33-37,共5页
Objective To probe into whether an acupoint-like and meridian-like structure was existed in platyfish. Methods Adult platyfish was put in 30 μM 4-Di-2-ASP water solution for 3 h, then, in pipe water for 20min, afterw... Objective To probe into whether an acupoint-like and meridian-like structure was existed in platyfish. Methods Adult platyfish was put in 30 μM 4-Di-2-ASP water solution for 3 h, then, in pipe water for 20min, afterward, the fish was anesthetized in 10% aether water solution, and the fluorescent labeling was observed under fluorescent microscope with B-3A combination filter. Results The labels observed under the microscope were in round bright dot, a majority of dots were distributed separately and a part of them was in cluster (2- 5 dots/cluster) on various parts of the body in regular arrangement. The labels on the head were circularly distributed around the eye and two arches were formed posterior to the eye and in the inferior 3/4 quadrant. These two arches joined one arch in the anterior superior 1/4 quadrant. On the fish trunk, it was observed that the labels were distributed from the back to the abdomen along the longitudinal axis of the trunk, forming 6 lines, located on No. 2, 4, 6, 7, 8 and 9 scale rows successively on the dorsal part of fish. Each line was composed of 7 to 22 label clusters and 1 -5 labels were counted in each cluster. The labels were arranged as 3-4 lines on the tail. Conclusion 1) Acupoint-like and meridian-like structure was existed in platyfish. 2)The skin sensory organs of animal were not distributed evenly all over the body. Instead, a number of sensory organs were put together in cluster and a number of them were in linear distribution regularly along the long axis of the trunk, which was similar to the distribution of traditional meridians and acupoints. 展开更多
关键词 Platyfish Research of meridian and collateral Research of acupoint Neuromast
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Ingestion of Brachionus plicatilis under different microalgae conditions 被引量:3
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作者 周文礼 唐学玺 +3 位作者 乔秀英 王悠 王仁君 冯蕾 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期473-479,共7页
The effects of four microalgae, Chlorella vulgaris, Platymonas helgolandicavar, Isochrysis galbana, and Nitzschia closterium on the grazing and filtering rates of the marine rotifer, Brachionus plicatilis, were evalua... The effects of four microalgae, Chlorella vulgaris, Platymonas helgolandicavar, Isochrysis galbana, and Nitzschia closterium on the grazing and filtering rates of the marine rotifer, Brachionus plicatilis, were evaluated under laboratory conditions. The grazing rates in separate cultures of the four microalga were as follows: C. vulgaris 〉 P. helgolandicavar 〉 L galbana 〉 N. closterium. However, the filtering rates occurred in the following order: P. helgolandicavar 〉 N. closterium 〉 C. vulgaris 〉 L galbana. A mixed diets experiment revealed that P. helgolandicavar was the preferred diet of B. plicatilis. In addition, the grazing rate of B. plicatilis increased gradually as the density of the microalgae increased, until concentrations of 2.5×10^6 cells mL^-1 for C. vulgaris and 1.5×10^6 cells mL^-1 for I. galbana were obtained. Furthermore, the filtering rate increased slightly when the density of the microalgae was low, after which it declined as the microalgal density increased. The grazing rates of B. plicatilis were as follows during the different growth phases: stationary phase 〉 exponential phase 〉 lag phase 〉 decline phase. Additionally, the filtering rates during the growth phases were: exponential phase 〉 lag phase 〉 stationary phase 〉 decline phase. The results of this study provide foundational information that can be used to explore the optimal culture conditions for rotifers and to promote the development of aquaculture. 展开更多
关键词 Brachionus plicatilis MICROALGAE grazing rate filtering rate SELECTIVITY
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Analysis of phospholipids in microalga Nitzschia closterium by UPLC-Q-TOF-MS 被引量:6
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作者 严小军 李海英 +1 位作者 徐继林 周成旭 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期106-112,共7页
Precise structural identification of phospholipids in the microalga Nitzschia closterium has been established using ultra performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectr... Precise structural identification of phospholipids in the microalga Nitzschia closterium has been established using ultra performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (UPLC-ESI-Q-TOF-MS) for direct analysis of total lipid extracts.Mass spectrometry was performed in reflective time-of-flight using electron spraying ionization in negative mode.Phospholipid molecular species identification was based on the characteristic product ions and neutral loss yielded by different phospholipids under ESI-MS/MS mode.The molecular species were confirmed by the carboxylate anions produced by phospholipids in negative mode;the regiospecificity of the two acyl chains was determined from the ratio of sn-1 to sn-2 carboxylate anion abundances.As a result,18 lipid molecular species were identified for the first time in this microalga,comprising seven phosphatidylcholines (PC),two phosphatidylethanolamines (PE),two phosphatidylinositols (PI),and seven phosphatidylglycerols (PG).Lipid standards of PC,PE,PI,and PG were added to the total lipids as internal standards for semiquantitative analysis,revealing concentrations of phospholipids in this species between 0.09 and 3.37 nmol/mg.This method can produce a full structural profile of intact phospholipid molecular species and can be used for study of the physiological and ecological functions of lipids by monitoring their individual changes over time. 展开更多
关键词 Nitzschia closterium PHOSPHOLIPIDS UPLC-Q-TOF-MS
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Preparation and characteristics of biosilica derived from marine diatom biomass of Nitzschia closterium and Thalassiosira 被引量:1
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作者 漆亚 王欣 成家杨 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期668-680,共13页
In this study, biosilica of high purity was successfully prepared from marine diatom (Nitzschia closterium and Thalassiosira) biomass using an optimized novel method with acid washing treatment followed by thermal t... In this study, biosilica of high purity was successfully prepared from marine diatom (Nitzschia closterium and Thalassiosira) biomass using an optimized novel method with acid washing treatment followed by thermal treatment of the biomass. The optimal condition of the method was 2% diluted HCl washing and baking at 600℃. The SiO2 contents of N. closterium biosilica and Thalassiosira biosilica were 92.23% and 91.52%, respectively, which were both higher than that of diatomite biosilica. The SiO2 morphologies of both biosilica are typical amorphous silica. Besides, IV. closterium biosilica possessed micropores and fibers with a surface area of 59.81 m^2/g. And Thalassiosira biosilica possessed a mesoporous hierarchical skeleton with a surface area of 9.91 m^2/g. The results suggest that the biosilica samples obtained in this study present highly porous structures. The prepared porous biosilica material possesses great potential to be used as drug delivery carrier, biosensor, biocatalyst as well as adsorbent in the future. 展开更多
关键词 BIOSILICA PREPARATION DIATOM Nitzschia closterium THALASSIOSIRA
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Succession and seasonal variation in epilithic biofilms on artificial reefs in culture waters of the sea cucumber Apostichopus japonicus 被引量:3
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作者 LIU Liming DU Rongbin +2 位作者 ZHANG Xiaoling DONG Shuanglin SUN Shichun 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期132-152,共21页
Periphytic biofilms in aquaculture waters are thought to improve water quality, provide an additional food source, and improve the survival and growth of some reared animals. In the AsiaPacific region, particularly in... Periphytic biofilms in aquaculture waters are thought to improve water quality, provide an additional food source, and improve the survival and growth of some reared animals. In the AsiaPacific region, particularly in China, artificial reefs are commonly used in the commercial farming of sea cucumbers. However, few studies have examined the epilithic biofilms on the artificial reefs. To gain a better understanding of the succession of epilithic biofilms and their ecological processes in sea cucumber culture waters, two experiments were conducted in culture waters of the sea cucumber Apostichopus japonicus in Rongcheng, China, using artificial test panels. On the test panels of succession experiment, more than 67 species were identified in the biofilms. On the test panels of seasonal variation experiment, more than 46 species were recorded in the biofilms. In both experiments, communities of epilithic biofilms were dominated by diatoms, green algae and the annelid Spirorbis sp. In the initial colonization, the dominant diatoms were Cocconeis sp., Amphora spp. and Nitzschia closterium in June, which were succeeded by species of Navicula, Cocconeis and Nitzschia(July to September), and then by Licmophora abbreviata, Nitzschia closterium and Synedra spp. in the following months. A diatom bloom in the autumn and filamentous green algae burst in the summer were also observed. Ecological indices well annotated the succession and seasonal changes in epilithic communities. Multidimensional scaling(MDS) analysis found significant differences in diatom community composition among months and seasons. Fast growth of biofilms was observed in the summer and autumn, whereas the biomass of summer biofilms was largely made up of filamentous green algae. Present results show that the components of epilithic biofilms are mostly optimal foods of A. japonicus, suggesting that biofilms on artificial reefs may contribute important nutritional sources for sea cucumbers during their growth seasons. Future works should include quantitative determination of the contribution of epilithic biofilms to the diet of A. japonicus, potential roles of epilithic biofilms in regulating the water quality of sea cucumber ponds, and the regulation of epilithic biofilms in sea cucumber culture ponds. 展开更多
关键词 artificial reef sea cucumber culture waters epilithic biofilm succession seasonal variation Apostichopus japonicus diatom
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Cylindrotheca closterium Is a Species Complex as Was Evidenced by the Variations of rbcL Gene and SSU rDNA
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作者 LI Haitao YANG Guanpin SUN Ying WU Suihan ZHANG Xiufang 《Journal of Ocean University of China》 SCIE CAS 2007年第2期167-174,共8页
The genus Cylindrotheca consists of a small group of marine diatoms with a few species described. Eleven isolates of diatoms identified as Cylindrotheca closterium morphologically were obtained from Jiaozhou Bay with ... The genus Cylindrotheca consists of a small group of marine diatoms with a few species described. Eleven isolates of diatoms identified as Cylindrotheca closterium morphologically were obtained from Jiaozhou Bay with their nuclear-encoded small-subunit ribosomal RNA (SSU rDNA) and chloroplast-encoded rbcL gene sequences determined in this study. Interestingly, very high sequence divergences of SSU rDNA and rbcL gene were found among these isolates, and numerous nucleotide variation of rbcL gene caused relatively few variation of deduced amino acid sequence. Phylogenetic analyses based on SSU rDNA and rbcL gene, respectively, grouped the isolates into 6 clades. Phylogenetic tree of SSU rDNA placed all the Cylindrotheca isolates together, separating them into two lineages clearly. LineageⅠ was composed of the eleven C. closterium isolates obtained in this study together with another C. closterium isolate, but some clades were not well supported. LineageⅠwas contained two C. closterium isolates and one C. fusiformis isolate. Phylogenetic analysis of rbcL gene also separated the Cylindrotheca isolates into two well-defined lineages. The eleven C. closterium isolates formed a lineage and all clades were supported strongly. Statistical comparisons of SSU rDNA indicated that the average distance within lineageⅠwas significantly higher than that of other microalgae species (P 〈0.01). These results suggested the existence of cryptic species within C. closterium. 展开更多
关键词 Cylindrotheca closterium species complex rbcL gene SSU rDNA
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China Unveils Its First Mars Probe and Rover
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作者 YAO Tianyu 《Aerospace China》 2016年第3期60-60,共1页
A press conference was held in Beijing on August 23,marking the launch of a public competitive campaign to obtain a name and logo for China’s Mars mission.The project and its progress were introduced at the conferenc... A press conference was held in Beijing on August 23,marking the launch of a public competitive campaign to obtain a name and logo for China’s Mars mission.The project and its progress were introduced at the conference and the external appearance of the Mars probe and the rover was revealed.China’s Mars mission will be implemented in two steps.The objective of the first step is to achieve orbiting,landing,and roving.Mars sampling will be the purpose of the second step。 展开更多
关键词 rover campaign landing marking appearance Rover Probe launch steps roving
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The clinical and pathological characteristics of Chinese patients with pauci-immune crescent glomerulonephritis 被引量:1
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作者 唐政 姚小丹 +4 位作者 胡伟新 曾彩虹 陈惠萍 刘志红 黎磊石 《Chinese Medical Journal》 SCIE CAS CSCD 2001年第4期38-42,105,共6页
目的 对寡免疫复合物型新月体肾炎进行临床病理分析。方法 采用病理检查包括 :光镜检查、免疫病理分析、血清学检查、肾功能检查以及统计学分析。结果  6 4 0 0例非移植肾活检中发现 2 4例寡免疫复合物型新月体肾炎 (PICGN)患者 ,占... 目的 对寡免疫复合物型新月体肾炎进行临床病理分析。方法 采用病理检查包括 :光镜检查、免疫病理分析、血清学检查、肾功能检查以及统计学分析。结果  6 4 0 0例非移植肾活检中发现 2 4例寡免疫复合物型新月体肾炎 (PICGN)患者 ,占肾活检总数的 0 37% ,占新月体肾炎总数的 2 3 9% ,其中女性 16例 ,男性 8例 ,平均年龄 33岁。血管炎中微型多动脉炎 (33 3% )和结节性多动脉炎 (8 3% )为常见继发病因。抗中性粒细胞胞浆抗体 (ANCA)阳性率为 52 2 %。临床上多表现为急进性肾功能减退 (75 0 % ) ,发作性肉眼血尿发生率高 (58 3% ) ,高血压发生率为 4 5 8% ,肾病综合症发生率为 4 1 7% ,2 5%患者出现少尿无尿症状。除贫血外 ,肾外表现较少。病理上血管襻坏死 (6 2 5% )、单核及中性粒细胞浸润(6 6 7% )及小血管炎等为常见的急性病变 ;然而 ,小球硬化 (4 5 8% )、小管萎缩 (83 3% )、间质纤维化 (75 0 % )等慢性化病变也较严重。 2 2例患者行免疫抑制治疗 ,16例随访 8— 92个月 ,有 4例肾功能在正常范围 (<12 4 μmol/L) ,8例行非透析保守治疗 ,仅 4例进入终末期肾功能衰竭需进行维持性血透析治疗。结论 免疫抑制冲击治疗是治疗PICGN的有效方法。 展开更多
关键词 pauci-immune crescent glomerulonephritis·clinico-pathology·anti-neutrophil cytoplasmic antibody
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Glomerular chemokine expression and the effect of steroid and cyclophosphamide pulse therapy in human crescentic glomerulonephritis
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作者 陈书芬 刘志红 +3 位作者 陈惠萍 周虹 王建平 黎磊石 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第9期1301-1307,共7页
OBJECTIVE: To study glomerular expression of C-C chemokines, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha and beta (MIP-1alpha, MIP-1beta) and the effect of steroid and cyclophosp... OBJECTIVE: To study glomerular expression of C-C chemokines, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha and beta (MIP-1alpha, MIP-1beta) and the effect of steroid and cyclophosphamide (CTX) intermittent intravenous pulse therapy on expression in patients with crescentic glomerulonephritis (CGN) to further investigate the underlying mechanism of the treatment. METHODS: Twelve patients with initial biopsy-proven CGN(2), 6 with lupus nephritis (lupus-CGN, LN-CGN) and 6 with vasculitis, (vasculitis-CGN, V-CGN) were enrolled in this study. They underwent an initial biopsy before steroid and CTX intermittent intravenous pulse therapy and were biopsied again one to three months later. Expression of MCP-1, MIP-1alpha, MIP-1beta, and CD68 in glomeruli with cellular and fibrocellular crescents were examined by immunohistochemical analysis in serial sections of renal biopsies. The effect of the pulse therapy on histopathological changes was also observed. RESULTS: Although steroid and CTX intermittent intravenous pulse therapy markedly reduced the degree of glomerular crescent formation both in LN-CGN and V-CGN, the effect of the therapy on glomerular chemokine expression was significantly different between LN-CGN and V-CGN. It was found that steroid and CTX intermittent intravenous pulse therapy reduced the expression of CD68, MCP-1, and MIP-1alpha, but had no effect on MIP-1beta in glomeruli with cellular crescents of patients with LN-CGN. In patients with V-CGN, the therapy also reduced the expression of CD68, but had no effect on MCP-1, MIP-1alpha, and MIP-1beta in glomeruli with cellular crescents. It was noted that the degree of glomerulosclerosis and tubular interstitial fibrosis increased more significantly at the second biopsy in V-CGN as compared to LN-CGN. CONCLUSIONS: The efficacy of steroid and CTX intermittent intravenous pulse therapy in CGN might be affected by reduction of glomerular chemokine expression. The different changes in glomerular expression of MCP-1 and MIP-1alpha in patients with LN-CGN and V-CGN after pulse therapy may correlate to different responses to treatment and prognosis. 展开更多
关键词 Adolescent Adrenal Cortex Hormones Adult Antigens CD Antigens Differentiation Myelomonocytic Biopsy Chemokines CC Child CYCLOPHOSPHAMIDE Female GLOMERULONEPHRITIS Humans Kidney Glomerulus Macrophage Inflammatory Protein-1 Male Middle Aged Monocyte Chemoattractant Protein-1
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The distribution and significance of renal infiltrating cells in patients with diffuse crescentic glomerulonephritis
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作者 唐政 吴燕 +5 位作者 胡伟新 姚小丹 周红 陈惠萍 刘志红 黎磊石 《Chinese Medical Journal》 SCIE CAS CSCD 2001年第12期35-37,103-104,共5页
Objective To study the significance and distribution of renal infiltrating cells, including monocytes (CD68+ cells), proliferative cell nuclear antigen positive cells (PCNA+ cells), CD4+ and CD8+ cells in diffuse cres... Objective To study the significance and distribution of renal infiltrating cells, including monocytes (CD68+ cells), proliferative cell nuclear antigen positive cells (PCNA+ cells), CD4+ and CD8+ cells in diffuse crescent glomerulonephritis (DCGN). Methods Fifty-six patients with DCGN were studied, including 10 cases of anti-glomerular basement membrane (GBM)-type Ⅰ DCGN, 26 immune complex-type Ⅱ DCGN, and 20 cases of pauci-immune-type Ⅲ DCGN. Glomerular and interstitial infiltrates of CD68+ and PCNA+ cells, and interstitial infiltrates of CD4+ and CD8+ cells were detected by using four-layer PAP methods. Results There was a significant increase of renal infiltrating CD68+, PCNA+, CD4+ and CD8+ cells in patients with DCGN compared with that in normal controls. In patients with type Ⅰ DCGN, there was a higher number of renal infiltrating CD68+ and PCNA+ cells than that in patients with type Ⅱ and Ⅲ DCGN. A glomerular infiltrates of CD68+ and PCNA+ cells correlated with the interstitial infiltrates of CD4+ cells in type Ⅰ or Ⅲ DCGN patients. In lupus DCGN patients, the numbers of renal infiltrating CD68+ and PCNA+ cells were similar to vasculitis or type Ⅲ DCGN patients.Conclusion These findings demonstrate that the renal infiltrates of CD68+ and PCNA+ cells play an important role in patients with DCGN, that the infiltrates of CD4+ cells correlate with the infiltrates of CD68+ and PCNA+ cells may be an active marker of DCGN, and that cell-mediated immunity may contribute to crescent formation in lupus DCGN patients. 展开更多
关键词 CD68 + cells · PCNA + cells · CD8 + cells · crescentic glomerulonephritis
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Feathered sand ridges in the Kumtagh Desert and their position in the classification system 被引量:2
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作者 QU JianJun LIAO KongTai +3 位作者 DONG GuangRong NIU QingHe JING ZheFan HAN QinJie 《Science China Earth Sciences》 SCIE EI CAS 2011年第8期1215-1225,共11页
Feathered sand ridges in the northeastern Kumtagh Desert in China cover an area of 4016 km 2 and consist of crescent sand ridges and interridge tongue-shaped dunes.Differences in grain size,mineral composition and alb... Feathered sand ridges in the northeastern Kumtagh Desert in China cover an area of 4016 km 2 and consist of crescent sand ridges and interridge tongue-shaped dunes.Differences in grain size,mineral composition and albedo between crescent sand ridges and tongue-shaped dunes,and between windward and leeward slopes of tongue-shaped dunes,result in their feathery appearance in aerial and satellite imagery.Measurements of the sand drift potential in the region show that the sand-moving wind for feathered sand ridges can be divided into three sectors;i.e.north-northeasterly,easterly and east-northeasterly sectors roughly corresponding to the southeast,northwest and southwest slip faces.Our findings suggests that the crescent sand ridges resulting from the connection of barchan dunes along the prevailing wind direction are longitudinal dune ridges rather than transverse ones.Tongue-shaped dunes and quasi-dune shapes have obvious distinctions and are new transverse dune types.According to McKee's dune shape classification,the feathered sand ridges are not a deformation dune type but a complex one.According to Wu's dune morphological and genetic classification,they are not dune ridges or compound dune ridges that form under the action of unidirectional winds or two winds intersecting at an acute angle,but are complex dune ridges that form under the action of three winds intersecting at an acute angle. 展开更多
关键词 Kumtagh Desert feathered sand ridge tongue-shaped dune morphologic characteristics aeolian sand landform classification
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Assessments of tear meniscus height, tear film thickness, and corneal epithelial thickness after deep anterior lamellar keratoplasty 被引量:2
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作者 Wen-jia XIE Ye-sheng XU +1 位作者 Xia ZHANG Yu-feng YAO 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第3期218-226,共9页
Objective: To assess the lower tear meniscus height(LTMH), central tear film thickness(CTFT), and central corneal epithelial thickness(CCET) after deep anterior lamellar keratoplasty(DALK). Methods: This was... Objective: To assess the lower tear meniscus height(LTMH), central tear film thickness(CTFT), and central corneal epithelial thickness(CCET) after deep anterior lamellar keratoplasty(DALK). Methods: This was a retrospective cross-sectional study of 20 patients who had DALK in one eye over a three-month period. LTMH, CTFT, and CCET of the operated eyes and the unoperated fellow eyes were measured using high-definition optical coherence tomography(HD-OCT). Correlations between three OCT assessments and age, time following surgery, graft size, bed size, and the number of residual sutures were analyzed. Results: Compared to patients with keratoconus, patients with other corneal conditions had significantly higher CCET in the fellow eye(P=0.024). For all patients, CCET in the operated eye was significantly negatively correlated with the number of residual sutures(R=-0.579, P=0.008), and was significantly positively correlated with time following surgery(R=0.636, P=0.003). In the fellow eye, a significant positive correlation was found between age and CCET(R=0.551, P=0.012), and a significant negative correlation between age and CTFT(R=-0.491, P=0.028). LTMH was found to be significantly correlated between operated and fellow eyes(R=0.554, P=0.011). There was no significant correlation between LTMH and age, bed/graft size, time following surgery, or residual sutures(all possible correlations, P0.05). Conclusions: Patients with keratoconus tend to have a thinner central corneal epithelium. Corneal epithelium keeps regenerating over time after DALK. DALK did not induce a significant change in tear volume compared with the fellow eye. Postoperative tear function might depend on an individual's general condition, rather than on age, gender, bed/graft size, time following surgery, or residual sutures. 展开更多
关键词 Tear meniscus height Corneal epithelial thickness Tear film Deep anterior lamellar keratoplasty (DALK) High-definition optical coherence tomography (HD-OCT) KERATOCONUS
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Evolution of downsized crescent-shaped dune in wind tunnel experiment 被引量:1
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作者 ZHANG Yang WANG Yuan JIA Pan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第1期143-151,共9页
The migration of a downsized crescent-shaped dune was investigated in a wind tunnel experiment.Quantified upwind influx and vertical oscillation of the sand bed were introduced to modulate the saturation level of the ... The migration of a downsized crescent-shaped dune was investigated in a wind tunnel experiment.Quantified upwind influx and vertical oscillation of the sand bed were introduced to modulate the saturation level of the sand flux above the dune surface to affect dune evolution.The evolution was recorded by top-view photography and then abstracted as the evolution of self-defined characteristic quantities using a digital image processing algorithm.The results showed that,in contrast to the case for spanwise quantities,the evolution of streamwise quantities corresponds to a linear increase in the modulation magnitude more positively and in a monotonic and convergent manner.In contrast with quantities on the windward face,the changes in quantities with respect to the horns were nonmonotonic with time and almost uncorrelated with the variation in modulation strength,which reveals the distinctiveness of leeside evolution. 展开更多
关键词 crescent-shaped dune wind tunnel experiment saturation level of sand flux digital image processing dune evolution
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