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太行山油松人工林材积生长率表的编制 被引量:2
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作者 梁守伦 朱世忠 +2 位作者 王洪涛 王万常 冀永敏 《山西林业科技》 北大核心 1996年第4期8-11,共4页
收集了太行山区油松人工林标准地148块及其平均解析木148株,利用曲线PV=ADB分别立地质量等级和密度级编制了材积生长率表。在解析木株数少、直径范围小的情况下,用解析木各年龄的数据编表,提高了解析木的信息利用率,编... 收集了太行山区油松人工林标准地148块及其平均解析木148株,利用曲线PV=ADB分别立地质量等级和密度级编制了材积生长率表。在解析木株数少、直径范围小的情况下,用解析木各年龄的数据编表,提高了解析木的信息利用率,编出了满足精度要求的生长率表,编表中使用与生长率公式相对应的直径,避免了不直接对应的误差。 展开更多
关键词 材积生长率表 生长率曲线 油松
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杉木人工林材积生长率表编制的研究 被引量:10
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作者 程光明 《福建林业科技》 北大核心 2006年第3期56-59,共4页
利用森林资源连续清查固定样地中的复位样木生长量测定数据,以材积生长率Pv为因变量,年龄T和胸径D为辅助变量,选择Pv=aTbDc为基本模型,采用逐步回归技术建立可变参数的材积生长率模型,并用改进单纯形法优化参数。结果表明:材积生长率表... 利用森林资源连续清查固定样地中的复位样木生长量测定数据,以材积生长率Pv为因变量,年龄T和胸径D为辅助变量,选择Pv=aTbDc为基本模型,采用逐步回归技术建立可变参数的材积生长率模型,并用改进单纯形法优化参数。结果表明:材积生长率表在理论值与实际值差异不显著,且误差小,精度高,在林业生产实践中有应用价值。 展开更多
关键词 杉木 生长率表 模型
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利用连清资料编制材积生长率表 被引量:11
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作者 曾伟生 《中南林业调查规划》 1992年第4期19-22,共4页
利用广西的森林资源连续清查资料,以实例的形式详细介绍了编制单木和林分材识生长率表的方法和步骤,为今后各省区编制生长率表提供了重要的参考依据。
关键词 森林资源 生长率表 材积
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连江县湿地松人工林单木材积生长率表的研制 被引量:3
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作者 陈文雄 《林业勘察设计》 2012年第2期5-8,共4页
在连江县森林资源连续清查的湿地松人工林固定样地中,随机抽取复位样木,按前后两次测定的生长量数据计算材积生长率。以材积生长率为因变量,年龄和胸径为自变量,选择理查德方程为基本方程,对变量及参数作数学处理后构建材积生长率模型,... 在连江县森林资源连续清查的湿地松人工林固定样地中,随机抽取复位样木,按前后两次测定的生长量数据计算材积生长率。以材积生长率为因变量,年龄和胸径为自变量,选择理查德方程为基本方程,对变量及参数作数学处理后构建材积生长率模型,用免疫进化算法进行优化拟合。据此编制的材积生长表经检验理论值与实际值差异不显著,精度符合要求,在林业生产上有实用价值。 展开更多
关键词 湿地松 生长率表 模型
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一元立木材积生长率表的编制
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作者 董景林 冯保新 《吉林林业科技》 北大核心 1991年第3期19-21,24,共4页
关键词 一元立木 材积 生长率表 材积
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利用PB—700微机编制林木生长率表
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作者 张军 《内蒙古林业调查设计》 1989年第4期8-16,共9页
关键词 林木 生长率表 编制 计算机 数据处理
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巢湖地区国营林场杉木,马尾松,黑松人工林立木蓄积连年生长率表的编制
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作者 刘兆平 《安徽林业科技》 1991年第2期34-36,F003,共4页
关键词 林场 立木蓄积 生长率表 人工林
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柳杉人工林材积生长率表编制的研究
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作者 叶振环 《林业勘察设计》 1999年第2期7-11,共5页
把材积生长率作为年龄、胸径的函数,采用山本公式、多模型选优法、逐步回归法建立柳杉人工林材积生长率的数学模型,并用改进单纯形法进行优化,从而为提高材积生长率表的编制精度提供客观依据。
关键词 柳杉人工林 材积生长率表 单纯形法 编制
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油松连年生长率表的研制
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作者 李德民 李世界 《辽宁林业科技》 1993年第3期19-22,共4页
依据154株油松解析木材料,用幂函数式P=aA^b100回归方法配置了油松树高、胸径、材积连年生长率回归方程并编表。其回归相关指数分别为0.949、0.950、0.948;估计精度分别为80%、87%、86%,经F检验,可应用于资源档案的消长分析,确定采... 依据154株油松解析木材料,用幂函数式P=aA^b100回归方法配置了油松树高、胸径、材积连年生长率回归方程并编表。其回归相关指数分别为0.949、0.950、0.948;估计精度分别为80%、87%、86%,经F检验,可应用于资源档案的消长分析,确定采伐量及生产。 展开更多
关键词 油松 连年生长率表 编制
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黑龙江省小兴安岭北坡林分生长率模型的建立 被引量:6
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作者 郑春华 高振寰 杨胜涛 《防护林科技》 2014年第7期32-33,共2页
通过采集的120 890株编表样木数据,编制了黑龙江省小兴安岭北坡的主要林分生长率表,确定了y=a+blnx(y—林分生长率,x—林分年龄)为林分总长率和净生长率回归模型。经检验,本生长率表精度较高、适用性强,可供生产经营单位、管理部门和科... 通过采集的120 890株编表样木数据,编制了黑龙江省小兴安岭北坡的主要林分生长率表,确定了y=a+blnx(y—林分生长率,x—林分年龄)为林分总长率和净生长率回归模型。经检验,本生长率表精度较高、适用性强,可供生产经营单位、管理部门和科学研究使用。 展开更多
关键词 小兴安岭北坡 主要林分 生长率表
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试论生长量表的两种编制方法
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作者 淡永红 《云南林业调查规划》 1989年第2期31-34,共4页
我在编制曲靖、东川地区云南松各直径材积生长量与材积生长率表的过程中发现了一个值得注意的问题:用径阶平均法与用直接输入法编的表,各自呈现出不同的规律性。一开始,我用CASIOfx—3600P的“LR“状态直接输入D(带皮直径)与Pd(平均年... 我在编制曲靖、东川地区云南松各直径材积生长量与材积生长率表的过程中发现了一个值得注意的问题:用径阶平均法与用直接输入法编的表,各自呈现出不同的规律性。一开始,我用CASIOfx—3600P的“LR“状态直接输入D(带皮直径)与Pd(平均年直径生长率)。由于数据量太大(相对于CASIO来说。有174对数据)。 展开更多
关键词 生长 生长率表 原木材积
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福建青冈天然林生长规律的研究 被引量:15
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作者 杨长职 《华东森林经理》 2005年第3期29-33,共5页
利用闽清雄江黄楮林自然保护区的福建青冈天然林解析木材料,选择合适的生长方程建立胸径、树高和材积生长模型,对其生长规律进行了分析,并编制了材积生长率表。
关键词 福建青冈 生长规律 生长模型 生长率表
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Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems 被引量:5
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作者 刘宝良 刘鹰 +3 位作者 刘子毅 仇登高 孙国祥 李贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期982-990,共9页
Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 (final density -39 kg/m^3), medium densities DE (-29 kg/m^3) and D3 (~19 kg/m^3), and low density D4 (-12 kg/m^3)- for 40 day... Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 (final density -39 kg/m^3), medium densities DE (-29 kg/m^3) and D3 (~19 kg/m^3), and low density D4 (-12 kg/m^3)- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight (SGRw) but did affect specific growth rate in terms of energy (SGRe). Stocking density significantly influenced the ration level (RLw and RLe), feed conversion ratio (FCRw and FCRe) and apparent digestibility rate (ADR). Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry. 展开更多
关键词 stocking density Atlantic salmon GROWTH body composition energy budget recirculatingaquaculture system
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Effect of Shrimp(Litopenaeus vannamei) Farming Waste on the Growth, Digestion, Ammonium-Nitrogen Excretion of Sea Cucumber(Stichopus monotuberculatus) 被引量:1
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作者 CHEN Yanfeng LUO Peng +1 位作者 HU Chaoqun REN Chunhua 《Journal of Ocean University of China》 SCIE CAS 2015年第3期484-490,共7页
In this study, specific growth rate(SGR), ingestion rate(IR), food conversion ratio(FCR), apparent digestion ratio(ADR) and ammonium-nitrogen excretion were determined for sea cucumber(Stichopus monotuberculatus) rear... In this study, specific growth rate(SGR), ingestion rate(IR), food conversion ratio(FCR), apparent digestion ratio(ADR) and ammonium-nitrogen excretion were determined for sea cucumber(Stichopus monotuberculatus) reared in plastic containers(70 L; 4 containers each diet treatment). Sea cucumbers were fed with five diets containing different amounts of farming waste from shrimp(Litopenaeus vannamei)(100%, 75%, 50%, 25% and 0) and a formulated compound(20% sea mud and 80% powdered algae). Sea cucumbers grew faster when they were fed with diet D(25% shrimp waste and 75% formulated compound) than those fed with other diets. Although IR value of sea cucumber fed with diet A(shrimp waste) was higher than those fed with other diets, both the lowest SGR and the highest FCR occurred in this diet group. The highest and the lowest ADR occurred in diet E(formulated compound) and diet A group, respectively, and the same to ammonium-nitrogen excretion. The contents of crude protein, crude lipid and total organic matter(TOM) in feces decreased in comparison with corresponding diets. In the feces from different diet treatments, the contents of crude protein and TOM increased gradually as the contents of crude protein and TOM in diets increased, while crude lipid content decreased gradually as the crude lipid content in diets increased. 展开更多
关键词 sea cucumber Stichopus monotuberculatus SHRIMP Litopenaeus vannamei GROWTH DIGESTION ammonium-nitrogenexcretion
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Growth and energy budget of juvenile lenok Brachymystax lenok in relation to ration level 被引量:1
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作者 刘洋 李钟杰 +3 位作者 张堂林 苑晶 牟振波 刘家寿 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期347-355,共9页
We evaluated the effect of ration level (RL) on the growth and energy budget of lenok Brachymystax lenok. Juvenile lenok (initial mean body weight 3.06±0.13 g) were fed for 21 d at five different ration level... We evaluated the effect of ration level (RL) on the growth and energy budget of lenok Brachymystax lenok. Juvenile lenok (initial mean body weight 3.06±0.13 g) were fed for 21 d at five different ration levels: starvation, 2%, 3%, 4% bwd (body weight per day, based on initial mean values), and apparent satiation. Feed consumption, apparent digestibility, and growth were directly measured. Specific growth rates in terms of wet weight, dry weight, protein, and energy increased logarithmically with an increase in ration levels. The relationship between specific growth rate in terms of wet weight (SGRw, %/d) and RL (%) was characterized by a decelerating curve: SGRw=- 1.417+3.1661n(RL+ 1). The apparent digestibility coefficients of energy exhibited a decreasing pattern with increasing ration level, and there was a significant difference among different RLs. Body composition was significantly affected by ration size. The relationship between feed efficiency rate in terms of energy (FERe) and RL was: FERe=- 14.167+23.793RL-3.367(RL)2, and the maximum FERe was observed at a 3.53% ration. The maintenance requirement for energy of juvenile lenok was 105.39 kJ BW (kg)-0.80/d, the utilization efficiency of DE for growth was 0.496. The energy budget equation at satiation was: 100IE=29.03FE+5.78(ZE+UE)+39.56 HE+25.63 RE, where IE is feed energy, FE is fecal energy, ZE+UE is excretory energy, HE is heat production, and RE is recovered energy. Our results suggest that the most suitable feeding rate for juvenile lenok aquaculture for wet weight growth is 2.89% bwd, whereas for energy growth, the suggested rate is 3.53% bwd at this growth stage. 展开更多
关键词 ration level GROWTH energy budget Brachymystax lenok
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Dietary guaiacol improves the growth of juvenile abalone,Haliotis discus hannai Ino
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作者 张文兵 麦康森 +2 位作者 徐玮 刘付志国 谭北平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期697-702,共6页
We conducted a preliminarily study on the effects of dietary guaiacol on growth performance of abalone, Haliotis discus hannai Ino. Seven semi-purified diets were formulated with graded levels of guaiacol (0, 5, 10, ... We conducted a preliminarily study on the effects of dietary guaiacol on growth performance of abalone, Haliotis discus hannai Ino. Seven semi-purified diets were formulated with graded levels of guaiacol (0, 5, 10, 50, 100, 500, and 1 000 mg kgl). Abalone (initial weight: 0.29 ± 0.01 g; initial shell length: 8.55 ± 0.27 mm) were fed with these diets in a re-circulated water system for 152 days. Guaiacol significantly improved the specific growth rate (SGR) (P〈0.05); excessive dietary guaiacol (1 000 mg kg1) led to significantly high mortality (P〈0.05), and lipid content in the soft body increased significantly after dietary guaiacol (P〈0.05). Activities of catalase and phenoloxidase (PO) in the viscera were significantly stimulated by dietary guaiacol (P〈0.05). Broken-line analysis based on SGR indicated that the minimum dietary guaiacol for the optimal growth of juvenile abalone is 15.43 mg ·kg^-1. 展开更多
关键词 Haliotis discus hannai GROWTH body composition GUAIACOL
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Comparative Utilization of Different Fibre Feedstuffs by Weaning/Growing Pigs in the Tropics 被引量:2
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作者 Emmanuel Oluropo Akinfala Omotola Macaulay Samuel Temitope Ogundeji 《Journal of Agricultural Science and Technology(A)》 2014年第2期149-154,共6页
This study was conducted to investigate the effect of feeding different fibre feedstuffs on the performance, nutrient utilization and economics of production of weaning/growing pigs. Five fibre feedstuffs--palm kernel... This study was conducted to investigate the effect of feeding different fibre feedstuffs on the performance, nutrient utilization and economics of production of weaning/growing pigs. Five fibre feedstuffs--palm kernel cake (PKC), wheat offal (WO), corn bran (CB), rice bran (RB) and brewers' dried grain (BDG) were used at 25% in each of the five experimental diets that were formulated in this study. Twenty weaner pigs (12.75 ± 0.6 kg) were used for the growth study while 15 pigs (14.95 ± 0.57 kg) were used for the digestibility study. The design of the experiment was completely randomized. The results of the study showed that the performance of the experimental animals were significantly influenced (P 〈 0.05) by the dietary treatments. The apparent digestibility of the crude protein, crude fiber and ether extract showed significant differences (P 〈 0.05) while there was no significant difference (P 〉 0.05) in the apparent digestibility of their dry matter, ash and nitrogen free extract. The diet that contained WO had the best growth response and apparent nutrient digestibility. Results of economics of production also showed that diet with WO gave the best (P 〈 0.05) value in feed cost/'kg gain and net profit/animal. It can be concluded from this study that although all the animals fed the different fibre feedstuffs performed satisfactorily on all the parameters monitored, but for optimum growth, apparent nutrients digestibility and economics of production. WO should be used as a fibre feedstuff in the diets of weaning/growing pigs in the tropics. 展开更多
关键词 PIGS performance DIGESTIBILITY economics of production DIETS
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Effects of Dietary Soy Isoflavones on Feed Intake,Growth Performance and Digestibility in Juvenile Japanese Flounder(Paralichthys olivaceus) 被引量:9
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作者 MAI Kangsen ZHANG Yanjiao +3 位作者 CHEN Wei XU Wei AI Qinghui ZHANG Wenbing 《Journal of Ocean University of China》 SCIE CAS 2012年第4期511-516,共6页
An 8-week feeding trial was conducted to investigate the effects of dietary soy isoflavones on feeding intake,growth performance,and digestion of juvenile Japanese flounder(Paralichthys olivaceus).Four isonitrogenous(... An 8-week feeding trial was conducted to investigate the effects of dietary soy isoflavones on feeding intake,growth performance,and digestion of juvenile Japanese flounder(Paralichthys olivaceus).Four isonitrogenous(49% crude protein) and isoenergetic(20.1 MJ kg-1) diets were formulated to contain four graded levels of soy isoflavones,namely,0,1,4 and 8 g soy isoflavones in 1 kg of diet.Each diet was randomly fed to triplicate tanks of fish(Initial average weight:2.58 g ± 0.01 g),and each tank was stocked with 35 fish.No significant difference was observed among diets with levels of 0,1 and 4 g kg-1 soy isoflavones in feed intake,weight gain,feed efficiency ratio(FER),proximate composition of fish whole body and apparent digestibility coefficients(ADC) of nutrients and energy(P>0.05).However,high dietary soy isoflavones level(8 g kg-1) significantly depressed weight gain,FER,whole-body crude lipid content of fish and ADC of nutrients(P<0.05).These results indicate that high level of dietary soy isoflavones(above 4 g kg-1) significantly depresses growth responses and FER of Japanese flounder.However,as the content of soy isoflavones in soybean meal is around 1 to 3 g kg-1,the adverse effects might be neglected when soybean products are used as a fish feed ingredient. 展开更多
关键词 soy isoflavones feed intake DIGESTIBILITY GROWTH Japanese flounder
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Feeder Type Affects Growth in Weanling Horses
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作者 Carol Jean Thompson Kevin Halden Kline 《Journal of Agricultural Science and Technology(A)》 2015年第7期616-620,共5页
In the interest of decreasing feed costs while maximizing the growth of weanling horses, this study examined the potential difference in the average daily gain (ADG), gain to feed ratio (G/F), and apparent dry mat... In the interest of decreasing feed costs while maximizing the growth of weanling horses, this study examined the potential difference in the average daily gain (ADG), gain to feed ratio (G/F), and apparent dry matter and crude protein digestibility in horses fed with the same diet provided in different feeder types. Sixteen weanling standardbred horses were used for the duration of the 9-week study. The horses were given 2.5% of their body weight in hay and grain daily, 2% hay and 0.5% grain, as fed in two equal feedings at 7:00 am and 7:00 pm. The first treatment used a combined hay and grain feeder with the hay rack positioned over a manger compartment. The second treatment provided hay in an open hay rack and grain in a separate, open-topped feed tub, not positioned under the hay rack. The two groups, with eight horses--four female and four male in each group, were fed in one manner or the other for the length of the study. The weanlings fed in the combined hay and grain feeder had a greater ADG (0.52 kg/d vs. 0.41 kg/d) and G/F (0.06 vs. 0.05) than the horses with the separate hay and grain feeders. Both ADG and G/F means between treatments were statistically different (P 〈 0.05). There was not a significant difference (P 〉 0.05) in the apparent digestibility of dry matter or crude protein between the two groups. Therefore, it was concluded that the combined feeding system resulted in greater growth and apparent G/F most likely due to decreased feed wastage; however, apparent digestibility was not different between feeding systems. 展开更多
关键词 HORSE GROWTH DIGESTIBILITY feeder.
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Study on the protein expression and amplification of HER2 gene in gastric cancer
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作者 Sunan Wang Yingying Li +4 位作者 Zhengshun Xu Wenzhao Zhao Tian Yun Wuling Zhu Yangkun Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第6期267-272,共6页
Objective: The aim of the study was to investigate the human epidermal growth factor receptor 2(HER2) gene amplification and protein expression and interpretation points in the stomach mixed carcinomas. Methods: Immun... Objective: The aim of the study was to investigate the human epidermal growth factor receptor 2(HER2) gene amplification and protein expression and interpretation points in the stomach mixed carcinomas. Methods: Immunohistochemistry(IHC) and fluorescence in situ hybridization(FISH) technique were used to detect HER2 gene amplification and expression of HER2 protein in 442 cases of gastric mixed carcinoma. Results: The expression rate of HER2 protein was 41.2%(182/442): the HER2 protein expression IHC 3+ extensive type in 18 cases, partial type in 21 cases, focal type in 8 cases, accounting for 10.6%(47/442); the HER2 protein expression IHC 2+ extensive type in 23 cases, partial type in 28 cases, focal type in 11 cases, accounting for 14.0%(62/442); the HER2 protein expression IHC 1+ extensive type in 27 cases, partial type in 31 cases, focal type in 15 cases, accounting for 16.5%(73/442). HER2 gene amplification rate of 442 cases was 16.1%(71/442). In 182 cases of HER2 protein positive expression, the HER2 gene cluster amplification rate was 14.8%(27/182), large granular amplification rate 11.0%(20/182), punctate amplification rate 6.0%(11/182) and high polysomy 7.1%(13/182). In 71 cases of HER2 gene amplification, there was 42 cases of HER2 protein expression IHC 3+, 22 cases of HER2 protein expression IHC 2+, and 7 cases of IHC 1+. Conclusion: HER2 detection of gastric mixed carcinoma has great heterogeneity, HER2 protein positive expression is divided into extensive type, partial type and focal type, and HER2 gene positive amplification is divided into cluster amplification, large granular amplification, punctate amplification and high polysomy. These typing of HER2 protein expression and HER2 gene amplification provide reference index to quantify for targeted therapeutic effect of anticancer drugs. 展开更多
关键词 stomach neoplasms mixed tumor human epidermal growth factor receptor 2 (HER2) gene HER2 proteinfluorescence in situ hybridization (FISH) immunohistochemistry (IHC)
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