期刊文献+
共找到2,140篇文章
< 1 2 107 >
每页显示 20 50 100
肾活检组织Masson染色方法的改良
1
作者 邓田 赵丽平 +1 位作者 贾丹 刘云霄 《实用医技杂志》 2024年第1期48-50,I0001,共4页
目的 通过对传统Masson染色方法的改良,解决肾活检光镜诊断中Masson染色存在的色彩浑浊,定位不清等问题。方法 收集2021-2022年的25例膜性肾病标本,分别采用改良染色法与传统方法,对比染色质量进行评分。结果 25例膜性肾病4种Masson染... 目的 通过对传统Masson染色方法的改良,解决肾活检光镜诊断中Masson染色存在的色彩浑浊,定位不清等问题。方法 收集2021-2022年的25例膜性肾病标本,分别采用改良染色法与传统方法,对比染色质量进行评分。结果 25例膜性肾病4种Masson染色结果比较,发现变色酸2R-亮绿+Bouin二次固定+胰酶消化法在色彩鲜明、嗜复红蛋白定位清晰及不易褪色、切片整体评分方面均优于传统方法,差异有统计学意义(P<0.05)。结论 改良后的Masson的染色方法在色彩对比度、持久度均优于传统方法。 展开更多
关键词 肾穿刺活检 masson染色 Bouin液 胰酶消化法
下载PDF
基于ANA模块的基面车床数字化改造应用
2
作者 刘义刚 赵玉苗 +1 位作者 耿秀明 田磊 《科技与创新》 2024年第22期38-40,共3页
首先对ANA模块的功能、软硬件配置要求、连接、使能及ANA模块的驱动配置作出阐述,并对其电气原理图进行详细分析,同时对基面车床工作台工作原理进行叙述,对比改造前后的工作情况,对基面车床改造过程的ANA模块的连接方法、启动配置、数... 首先对ANA模块的功能、软硬件配置要求、连接、使能及ANA模块的驱动配置作出阐述,并对其电气原理图进行详细分析,同时对基面车床工作台工作原理进行叙述,对比改造前后的工作情况,对基面车床改造过程的ANA模块的连接方法、启动配置、数据配置进行一一详述,最后对ANA模块的使用给基面车床数字化改造后带来的效率提升、精度提高予以肯定。 展开更多
关键词 ana模块 基面 车床数字化改造 生产效率
下载PDF
Complete Convergenceand Complete Moment Convergence for Weighted Sums of ANA Random Variables
3
作者 MENG Bing WU Qunying 《应用概率统计》 CSCD 北大核心 2024年第5期710-724,共15页
In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distri... In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distribution.The obtained results not only extend those of An and Yuan[1]and Shen et al.[2]to the case of ANA random variables,but also partially improve them. 展开更多
关键词 ana random variables complete convergence complete moment convergence weighted sums
下载PDF
显示胶原纤维的3种Masson染色方法的选择与比较
4
作者 曹阳 章如松 +4 位作者 魏雪 余波 李颖 饶秋 马恒辉 《诊断病理学杂志》 2024年第6期577-578,共2页
1资料与方法1.1临床资料收集60例不同组织标本作为研究对象,包括肺组织、肠黏膜组织、肾穿刺组织、升主动脉壁组织、子宫组织等,均用4%中性缓冲甲醛液固定(pH 7.2),常规脱水、透明、浸蜡、包埋,切片4μm。1.2试剂见表1。1.3操作步骤1.3.... 1资料与方法1.1临床资料收集60例不同组织标本作为研究对象,包括肺组织、肠黏膜组织、肾穿刺组织、升主动脉壁组织、子宫组织等,均用4%中性缓冲甲醛液固定(pH 7.2),常规脱水、透明、浸蜡、包埋,切片4μm。1.2试剂见表1。1.3操作步骤1.3.1Masson三色染色液具体操作步骤略,详见Masson三色染液(武汉塞维尔生物科技有限公司)说明书。1.3.2改良Masson三色染液具体操作步骤略,详见改良Masson三色染液(珠海贝索生物技术有限公司)说明书。 展开更多
关键词 胶原纤维 masson染色 病理诊断 选择 比较
下载PDF
Bouin氏固定液在Masson三色染色法中的应用
5
作者 魏海燕 丁瑞欣 杨建法 《诊断病理学杂志》 2024年第1期74-74,78,共2页
Masson染色是病理学中常用的特殊染色方法之一,其在穿刺组织评估纤维化中具备不可替代的优点。目前,Masson染色常用方法有Masson三色染色法及Pollak三色染色法,其中Masson三色染色法最为常用,但其染色方法偶有出现胶原纤维显色欠清、着... Masson染色是病理学中常用的特殊染色方法之一,其在穿刺组织评估纤维化中具备不可替代的优点。目前,Masson染色常用方法有Masson三色染色法及Pollak三色染色法,其中Masson三色染色法最为常用,但其染色方法偶有出现胶原纤维显色欠清、着色混乱等问题。 展开更多
关键词 Bouin氏固定液 masson三色染色 胶原纤维
下载PDF
Antibody Pattern: Correlation of Age and Gender in ANA and Anti-ds-DNA Prevalence
6
作者 Usama Ahmed Hijazi Mallick +1 位作者 Amber Khan Muhammad Zubair 《Journal of Clinical and Nursing Research》 2024年第6期373-381,共9页
The study was designed to find the prevalence of ANA antibodies and anti-dsDNA antibodies in samples tested at AFIP Rawalpindi and their correlation with age and gender and to find positive and negative predictive val... The study was designed to find the prevalence of ANA antibodies and anti-dsDNA antibodies in samples tested at AFIP Rawalpindi and their correlation with age and gender and to find positive and negative predictive values of ANA antibodies.For this purpose,twelve thousand nine hundred sixty-seven(12,967)patients were analyzed for ANA with four hundred sixty-eight(468)healthy samples tested as control and four thousand seven hundred three(4,703)patients tested for ds-DNA antibodies.Retrospective data of all samples tested by indirect immunofluorescence(IF)for ANA antibodies and dsDNA antibodies was collected.To address positive and negative predictive values another control group(autoimmunity not suspected)of serum samples was taken from the healthy population.For the first group,age,gender,ANA antibodies and ds-DNA antibodies results(both tests performed by IIF)data was collected from a computer record cell;for the second control group,ANA antibodies were performed by IIF.12,967 and 4,703 samples(Group 1)were tested for ANA antibodies and dsDNA antibodies,respectively,during this period.1,119(9%)and 99(2%)were found positive for ANA antibodies and ds DNA antibodies.Among these positive samples,850(76%)and 73(74%)were females respectively.Gender predisposition towards autoimmunity(ANA)was found significant with a P value of(P=0.001).Relation of age was also found significant with anti-ANA antibodies with a P value of(P=0.001).This study shows a negative correlation between age(P=0.025)and gender(P=0.001)with anti-dsDNA which is also significant.High prevalence was found below the mean age of 38 years(SD±16.635)for ANA antibodies and the mean age of 35 years(SD±15.066)for ds-DNA antibodies.The age of ANA antibodies and dsDNA antibodies positive patients ranged from 1 year old to 98 years old and 2 years old to 95 years old respectively.In the second(autoimmunity-free)control group,a total of 468 samples were tested for ANA antibodies and 9(2%)were found positive.Positive predictive value(PPV)was 8.6%and negative predictive value(NPV)was 98%.ANA is a sensitive test for autoimmunity and it is significantly related to female gender and increasing age.The low prevalence of ANA antibodies among clinically suspected cases suggests that rationalization of test prescriptions is needed.Anti-ds-DNA is also a sensitive test for diagnosis of SLE and it is significantly related to female gender and increasing age. 展开更多
关键词 ana Anti ds-DNA AUTOIMMUNITY SLE Immune fluorescence
下载PDF
Dyke-Davidoff-Masson综合征临床及影像特征分析
7
作者 曾林 倪广峰 《影像诊断与介入放射学》 2024年第3期213-217,共5页
目的分析Dyke-Davidoff-Masson综合征(DDMS)的临床表现与影像学特征。方法回顾性分析13例DDMS患者的临床及CT、MRI资料。12例行CT平扫,4例行MRI平扫,3例同时行CT及MRI平扫。结果后天性DDMS 8例,先天性DDMS 5例,临床表现为癫痫12例,偏瘫9... 目的分析Dyke-Davidoff-Masson综合征(DDMS)的临床表现与影像学特征。方法回顾性分析13例DDMS患者的临床及CT、MRI资料。12例行CT平扫,4例行MRI平扫,3例同时行CT及MRI平扫。结果后天性DDMS 8例,先天性DDMS 5例,临床表现为癫痫12例,偏瘫9例,肢体萎缩3例,智力低下及精神障碍各9例,面部不对称2例,性功能障碍1例,双侧耳廓畸形1例。DDMS分型:Ⅰ型6例,Ⅱ型4例,Ⅲ型3例。13例均见单侧大脑半球萎缩及同侧侧脑室扩大,中线结构向患侧移位12例,同侧基底神经节及大脑脚萎缩各10例,海马萎缩6例,交叉性小脑萎缩及双侧小脑萎缩各3例,脑软化9例,脑穿通畸形4例,胼胝体细小3例,脑裂畸形并透明隔缺如1例。13例均有不同程度同侧颅骨代偿性改变,表现为颅骨增厚、额窦及乳突过度气化。结论DDMS主要临床表现为癫痫、偏瘫、智力低下及精神障碍,典型影像征象为单侧大脑半球萎缩及同侧颅骨代偿性改变。 展开更多
关键词 Dyke-Davidoff-masson综合征 大脑半球萎缩 体层摄影术 X线计算机 磁共振成像
下载PDF
丙戊酸钠结合卡马西平对难治性癫痫患者脑电图变化及GADA、ANA水平表达的影响
8
作者 陈倩 韩忠海 +2 位作者 冯雪 王亚振 张蕾 《中国科技期刊数据库 医药》 2024年第6期0098-0102,共5页
以难治性癫痫患者为例,予丙戊酸钠+卡马西平治疗,全面性分析效果。方法 患者110例(收治:2022.01至2022.12),按掷硬币分组法,平分A、B组,予卡马西平、丙戊酸钠+卡马西平治疗。比对、分析效果。结果 (1)A组治疗总有效率为81.82%(45/55),B... 以难治性癫痫患者为例,予丙戊酸钠+卡马西平治疗,全面性分析效果。方法 患者110例(收治:2022.01至2022.12),按掷硬币分组法,平分A、B组,予卡马西平、丙戊酸钠+卡马西平治疗。比对、分析效果。结果 (1)A组治疗总有效率为81.82%(45/55),B组为96.36%(53/55),后者比前者高(2=5.986,P=0.014)。(2)治疗后,患者α、β波段脑电相关功率升高,δ、θ波段脑电相关功率降低,B组改善效果比A组好(P<0.05)。(3)患者GADA、ANA水平降低,且B组比A组低(P<0.05)。(4)治疗后,患者MoCA评分均提高,B组比A组高(P<0.05)。(5)A组不良反应发生率为9.09%(5/55),B组为5.45%(3/55),两组相比(2=0.135,P=0.714)。结论 丙戊酸钠结合卡马西平对难治性癫痫患者效果甚佳好,改善病症和脑电图变化,降低GADA、ANA水平,且不良反应少,安全性高。 展开更多
关键词 难治性癫痫 丙戊酸钠 卡马西平 脑电图变化 抗谷氨酸脱羧酶抗体(GADA) 抗核抗体(ana)
下载PDF
投加石灰石和菱镁矿对酸化土壤上马尾松(Pinus massoniana)林的影响 被引量:9
9
作者 黄永梅 段雷 +2 位作者 靳腾 杨永森 郝吉明 《生态学报》 CAS CSCD 北大核心 2006年第3期786-792,共7页
为了确定酸化森林生态系统的修复效果,在重庆铁山坪的马尾松林内设立了6个10m×10m的样地,其中2个作为对照样地,另外4个分别在土壤表面施撒石灰石和菱镁矿粉末,各有2个重复。在处理前和处理1a后的生长季末各进行了一次植被观测,协... 为了确定酸化森林生态系统的修复效果,在重庆铁山坪的马尾松林内设立了6个10m×10m的样地,其中2个作为对照样地,另外4个分别在土壤表面施撒石灰石和菱镁矿粉末,各有2个重复。在处理前和处理1a后的生长季末各进行了一次植被观测,协方差分析和多重比较的结果显示投加修复剂对马尾松生长的影响已经初步显现,马尾松的胸径增量和针叶平均长度都有显著的增加,而针叶中Ca、Mg元素含量也表现出显著的差别。另外,立木更新的变化、细根生物量的增加和物种多度的变化也较明显,总体来说生态系统有恢复的趋势。土壤上层细根的增加较快,这与在土壤表面施撒修复剂,上层土壤的化学变化较显著是一致的。而两种修复剂对生态系统的影响也表现出明显的差异,相对而言,施撒菱镁矿的效果可能会更好。由于土壤修复的效果是长期的,其影响观测还将继续下去。 展开更多
关键词 酸化 土壤修复 石灰石 菱镁矿 马尾松
下载PDF
心脏死亡器官捐献供肾零点活检冷冻组织改良PAS、Masson和PASM染色技术
10
作者 陈昕 黄海建 +2 位作者 王晨 陈新 陈惠玉 《临床与实验病理学杂志》 CAS 北大核心 2023年第9期1130-1132,共3页
随着国际标准化心脏死亡器官捐献(donation after cardiac death, DCD)工作的广泛开展,DCD来源的供肾在临床的应用逐渐增多。DCD供肾移植术后并发症亦呈逐渐增加趋势,如移植肾缺血再灌注损伤、机会性病毒感染、排斥反应等,这就要求临床... 随着国际标准化心脏死亡器官捐献(donation after cardiac death, DCD)工作的广泛开展,DCD来源的供肾在临床的应用逐渐增多。DCD供肾移植术后并发症亦呈逐渐增加趋势,如移植肾缺血再灌注损伤、机会性病毒感染、排斥反应等,这就要求临床医师评估供肾质量,除了临床评分及肉眼评估外,肾移植术中零点穿刺标本是评估移植肾功能、预测器官分配或远期存活的金标准[1]。 展开更多
关键词 肾移植 心脏死亡器官捐献 PAS masson PASM
下载PDF
Physiological responses of needles of Pinus massoniana elite families to phosphorus stress in acid soil 被引量:4
11
作者 HE You-lan LIU Ai-qin +4 位作者 Mulualem Tigabu WU Pengfei MA Xiang-qing WANG Chen Per Christer Oden 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期325-332,共8页
Pinus massoniana Lamb. is a major timber species widely planted in the South China, where the soil is acidic and deficient in phosphorus (P) due to fixation by aluminum and iron. Understanding the physiological resp... Pinus massoniana Lamb. is a major timber species widely planted in the South China, where the soil is acidic and deficient in phosphorus (P) due to fixation by aluminum and iron. Understanding the physiological responses to rhizospheric insoluble P is essential for enhancing plantation productivity. Thus, a sand culture experiment was conducted with four levels of P treatment (0, 5, 20 g insoluble P and 10 g soluble P), and 11 P. massoniana elite families. Physiological responses were measured after two months of stress. Compared to the normal soluble P treatment, the insoluble P treatment significantly reduced the proline content and the APase activity in the needles, while it significantly increased the catalase activity by 1.3-fold and malondialdehyde content by 1.2-fold. Soluble protein content was unaffected by the treatments, but chlorophyll content was significantly lower in P-deprived treatment compared with soluble and insoluble P treatments. These physiological responses also exhibited highly significant variation among families (p 〈 0.01). The findings suggest that increased catalase activities in the presence of insoluble P might be involved in the activation of an anti-oxidation defense mechanism that scavenges the reactive oxygen species elicited by the stress. And this response has a strong genetic control that can be exploited to identify desirable genotypes. 展开更多
关键词 masson pine phosphorus stress anti-oxidative system lipid peroxidation
下载PDF
Microwave vacuum drying characteristics of Pinus massoniana wood 被引量:3
12
作者 Li Xian-jun Li Wen-jun Zhang Bi-guang 《Forestry Studies in China》 CAS 2007年第1期63-67,共5页
Microwave-vacuum (MV) drying characteristics of plantation Masson pine (Pinus massoniana) were studied experimentally for various levels of microwave radiation time, initial moisture content 0VIC), vacuum level a... Microwave-vacuum (MV) drying characteristics of plantation Masson pine (Pinus massoniana) were studied experimentally for various levels of microwave radiation time, initial moisture content 0VIC), vacuum level and wood thickness. The results show that the process of MV drying for wood can be significantly divided into a short accelerating rate drying period, a long constant rate drying period and falling rate drying period, and the second drying period can extend to levels of mean MC below the fiber saturation point. With the increase of initial MC and microwave radiation time, the drying rate of wood increases significantly. The vacuum level affects the drying rate in a slightly positive way. Within the range of 2 to 6 cm, the effects of sample thickness on the drying rate can be negligible. 展开更多
关键词 WOOD DRYING microwave-vacuum masson pine
下载PDF
Microfibril angle variability in Masson Pine (Pinus massoniana Lamb.) using X-ray diffraction 被引量:1
13
作者 Zhang Bo Fei Ben-hua +1 位作者 Yu Yan Zhao Rong-jun 《Forestry Studies in China》 CAS 2007年第1期33-38,共6页
The microfibril angle of fiber walls is an ultra-mieroscopic feature affecting the performance of wood products. It is therefore essential to get more definitive information to improve selection and utilization. X-ray... The microfibril angle of fiber walls is an ultra-mieroscopic feature affecting the performance of wood products. It is therefore essential to get more definitive information to improve selection and utilization. X-ray diffraction is a rapid method for measuring microfibril angles. In this paper, the variability of microfibril angle in plantation-grown Masson pine was investigated by peak-fitting method. This method was compared with the traditional hand-drawn method, 40% peak height method and half peak height method. X-ray diffraction measurements indicated that the microfibril angle changed as a function of the position in the tree. The mean microfibril angle decreased more gradually as the distance increased from the pith and reached the same level in mature wood. The microfibril angle also seemed to decrease clearly from the base upward. Differences of angle-intensity curves between heartwood and sapwood were also examined. 展开更多
关键词 X-ray diffraction microfibril angle peak-fitting method half peak height method masson pine
下载PDF
Simulation of the biomass dynamics of Masson pine forest under different management
14
作者 ZHANG Gui-lian WANG Kai-yun +1 位作者 LIU Xin-wei PENG Shao-lin 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期305-311,共7页
TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cut... TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cutting). The purpose was to represent biomass dynamics involved in its development, which can provide scientific arguments for management of Masson pine forest. The results showed the scenario that 10% or 20% of biomass of the previous year was thinned every five years from 15 to 40 years made total biomass of pine forest increase slowly and it took more time to reach a mature community; If clear cutting and thinning were combined, the case C (clear cutting at 20 years of forest age, thinning 50% of remaining biomass at 30 years of forest age, and thinning 50% of remaining biomass again at 40 years of forest age) was the best scenario which can accelerate speed of development of Masson pine forest and gained better economic values. 展开更多
关键词 TREE submodel BIOMASS Rate of nitrogen uptake Dinghushan masson pine forest
下载PDF
Dyke-Davidoff-Masson综合征CT及MRI特征 被引量:1
15
作者 田斌 丁辉 +2 位作者 娄琴 张琴 李静 《中国医学影像技术》 CSCD 北大核心 2023年第11期1626-1629,共4页
目的 观察Dyke-Davidoff-Masson综合征(DDMS)CT及MRI特征。方法 回顾性分析8例DDMS患者临床及影像学资料,观察其CT及MRI表现。结果 8例CT和MRI均见患侧大脑半球萎缩、颅窝缩小;7例患侧侧脑室扩大,中线结构向患侧偏移,伴不同程度颅骨代... 目的 观察Dyke-Davidoff-Masson综合征(DDMS)CT及MRI特征。方法 回顾性分析8例DDMS患者临床及影像学资料,观察其CT及MRI表现。结果 8例CT和MRI均见患侧大脑半球萎缩、颅窝缩小;7例患侧侧脑室扩大,中线结构向患侧偏移,伴不同程度颅骨代偿性改变,包括颅骨代偿性增厚、鼻窦扩大、乳突过度气化等;5例丘脑萎缩;4例大脑脚萎缩;4例脑软化;1例豆状核萎缩伴钙化。结论 DDMS的CT及MRI表现具有一定特征性,包括受累侧大脑半球萎缩伴同侧颅骨代偿性改变。 展开更多
关键词 Dyke-Davidoff-masson综合征 脑萎缩 体层摄影术 X线计算机 磁共振成像
下载PDF
ANA-12靶向抑制BDNF/TrkB信号缓解奥沙利铂诱导化疗大鼠的痛觉行为
16
作者 赵佳佳 万文军 +2 位作者 杨荷雨 谢敏 刘玲 《天津医药》 CAS 北大核心 2023年第1期35-40,共6页
目的 探讨ANA-12靶向抑制脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)信号缓解奥沙利铂(OXA)化疗痛的作用及机制。方法 将18只雄性SD大鼠按照随机数字表法分为3组:对照组、OXA组以及OXA+ANA-12组,每组6只。OXA组和OXA+ANA-12组腹... 目的 探讨ANA-12靶向抑制脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)信号缓解奥沙利铂(OXA)化疗痛的作用及机制。方法 将18只雄性SD大鼠按照随机数字表法分为3组:对照组、OXA组以及OXA+ANA-12组,每组6只。OXA组和OXA+ANA-12组腹腔注射OXA(4 mg/kg,连续5 d)构建化疗痛模型,模型构建成功后OXA+ANA-12组进行ANA-12鞘内给药(20 g/L)。给药完毕后,对各组大鼠进行痛觉行为学检测,记录大鼠自发性缩足反射次数和机械痛觉阈值的变化;采用HE染色、免疫印记和免疫荧光检测脊髓炎性细胞浸润情况及白细胞介素(IL)-1β、肿瘤坏死因子(TNF)-α、离子钙结合衔接分子1(Iba1)、BDNF、TrkB和核转录因子κB(NF-κB)表达水平变化。结果 行为学分析显示,与对照组相比,OXA连续注射可显著增加自发缩足次数以及机械刺激敏感性;与OXA组相比,鞘内注射ANA-12显著降低自发缩足次数,增加机械性痛觉阈值。形态学及蛋白表达分析显示,与对照组相比,OXA诱导脊髓炎症,激活BDNF/TrkB信号,上调IL-1β、TNF-α、Iba1和NF-κB的表达;与OXA组相比,ANA-12显著抑制BDNF/TrkB信号,下调IL-1β、TNF-α、Iba1和NF-κB的表达水平。结论 ANA-12鞘内给药通过阻断BDNF/TrkB信号来抑制脊髓炎症,缓解化疗痛。 展开更多
关键词 化学疗法 肿瘤 局部灌注 脊髓炎 小神经胶质细胞 脑源性神经营养因子 受体 trkB 奥沙利铂 ana-12
下载PDF
Nail Holding Performance of Self-Tapping Screws on Masson Pine and Chinese Fir Dimension Lumbers
17
作者 De Li Bengang Zhang +7 位作者 Yuan Tu Guoming Xiao Meifen Tian Xiaoxue Xu Xiao Zhong Qiaoyan Zhang Zhigang Wu Jiankun Liang 《Journal of Renewable Materials》 EI 2023年第10期3725-3738,共14页
Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects o... Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored.The results showed that:(1)The nail holding strength of the tangential section was the maximum,followed by that of the radial section,and that of the cross section was the minimum.(2)The nail holding strength of Masson pine was higher than that of Chinese fir.(3)The nail holding strength grew with the increase in the diameter of self-tapping screws,but a large diameter would lead to plastic cracking of the timber,thus further affecting the nail holding strength.Masson pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm.(4)Under a large diameter of screws,prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength.(5)Prefabricated guiding bores were more necessary for the screw connection of Masson pine.The results obtained could provide a scientific basis for the screw connection design of Masson pine and Chinese fir timber structures. 展开更多
关键词 masson pine Chinese fir self-tapping screws nail holding performance
下载PDF
In Situ Generation of Copper Nanoparticles in Heat-Treated Copper-Containing Masson’s Pine as a Preservative Process for Sawn Timber
18
作者 Minting Lai Guijun Xie +2 位作者 Wanju Li Lamei Li Yongjian Cao 《Journal of Renewable Materials》 SCIE EI 2023年第6期2665-2678,共14页
Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lam... Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lamb.)was vacuum impregnated with a basic copper salt solution(copper hydroxide,diethanolamine,and polyethylene glycol 200)prior to heat-treatment at 220℃ for 3 h.Antifungal properties,surface chemistry,crystal structure and sugar contents were tested,compared with heat treatment alone.The results showed that the samples treated by heating without copper salt treatment showed poor suppression of fungal growth,the copperimpregnated heat-treated wood suppressed(100%)the growth of Botryodiplodia theobromae Pat.,Aspergillus niger V.Tiegh.,Penicillium citrinum Thom,and Trichoderma viride Pers.The combined results of X-ray photoelectron spectroscopy,X-ray diffraction and sugars analysis suggested that fungal inhibition by the heat-treated copper-bearing Masson’s pine was mainly due to the reduction of the metal salt by PEG200 at high temperature to generate copper nanoparticles.In addition,the reduced sugar content of the treated timber,and hence the nutrient substrate for spoilage microbes,reduced in the presence of the metal salts at high-temperature.This study has demonstrated an effective method of increasing low-grade wood’s utility and commercial value. 展开更多
关键词 Heat treatment masson’s pine sawn timber inhibition of fungal growth copper nanoparticles
下载PDF
H离子对Masson染色影响的机制探究与改进方法
19
作者 潘恋恋 薛先亚 +2 位作者 韩枭 刘鑫 任勇 《诊断病理学杂志》 2023年第12期1145-1146,共2页
Masson染色是鉴别胶原纤维与肌纤维的一种重要方法,可协助诊断一些疾病^([1])。其主要染液为丽春红与苯胺蓝,也是重要的阴离子染料,在医学领域中被广泛应用^([2])。在日常病理工作中,技术员经常遇到试剂盒反复开瓶后,丽春红与苯胺蓝着... Masson染色是鉴别胶原纤维与肌纤维的一种重要方法,可协助诊断一些疾病^([1])。其主要染液为丽春红与苯胺蓝,也是重要的阴离子染料,在医学领域中被广泛应用^([2])。在日常病理工作中,技术员经常遇到试剂盒反复开瓶后,丽春红与苯胺蓝着色暗淡,这会对病理诊断产生一定的影响^([3])。本文从丽春红与苯胺蓝的分子结构出发,探索两种染液染色失效的原因及改进方法,现介绍如下。1材料与方法1.1材料1.1.1标本选取2020-01—2021-12间本院病理科慢性阑尾炎石蜡包埋组织50例。 展开更多
关键词 H离子 masson染色 丽春红 苯胺蓝 阑尾
下载PDF
Fungal diversity and community composition responses to the reintroduction of fire in a non-managed Mediterranean shrubland ecosystem
20
作者 Juncal Espinosa Tatek Dejene +3 位作者 Mercedes Guijarro Xim Cerdá Javier Madrigal Pablo Martín-Pinto 《Forest Ecosystems》 SCIE CSCD 2023年第2期268-278,共11页
Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning ca... Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning can mitigate the risk of wildfires by reducing the fuel load but prescribed burning may also alter the soil properties and reduce microbial and fungal activity,causing changes in the availability of nutrients deep in the soil layer.Although fungal communities are a vital part of post-fire restoration,some fire effects remain unclear.To examine the short-term effects of prescribed burning on soil fungal communities in Doñana Biological Reserve(SW Spain),we collected soil samples pre-burn and 1 day,6 and 12 months post-burn from burned plots to perform physicochemical and metabarcode DNA analyses.Results:Prescribed burning had no significant effect on the total fungal operational taxonomic unit richness and abundance.However,changes in soil pH,nitrogen and potassium content post-burn affected fungal community composition.Small non-significant changes in pH and phosphorous affected the composition of ectomycorrhizal fungi.Conclusions:The ectomycorrhizal fungal community appears to be resilient to the effects of low-to moderate-intensity fires and saprotrophic taxa may benefit from this kind of fire.This finding revealed that prescribed burning is a potentially valuable management tool for reducing fire hazards in shrublands that has little effect on the total richness and abundance of fungal communities. 展开更多
关键词 Doñana National Park Ectomycorrhizal fungi Fire ecology Forest management Global change Prescribed burning WILDFIRE Saprotrophic fungi
下载PDF
上一页 1 2 107 下一页 到第
使用帮助 返回顶部