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A monitoring-modeling approach to SO42- and NO3- secondary conversion ratio estimation during haze periods in Beijing, China
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作者 Xiaoqi Wang Wei Wei +2 位作者 Shuiyuan Cheng Chong Zhang Wenjiao Duan 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期293-302,共10页
SO42- and NO3- are important chemical components of fine particulate matter(PM2.5),especially during haze periods.This study selected two haze episodes in Beijing,China with similar meteorological conditions.A monitor... SO42- and NO3- are important chemical components of fine particulate matter(PM2.5),especially during haze periods.This study selected two haze episodes in Beijing,China with similar meteorological conditions.A monitoring-modeling approach was developed to estimate the secondary conversion ratios of sulfur and nitrogen based on monitored and simulated concentrations.Measurements showed that in Episode 1(24th–25th October,2014),the concentrations(proportions)of SO42- and NO3- reached 35.1μg/m3(14.9%) and 55.0μg/m3(22.9%),while they reached 14.4μg/m3(9.3%) and 59.1μg/m3(38.1%)in Episode 2(26th–27th October,2017).A modeling system was applied to apportion Beijing’s SO42- and NO3- in primary and secondary SO42-/NO3- emitted from local and regional sources.Thus,secondary conversion contributions considering the local and regional level were defined.The former primarily focused on Beijing atmospheric oxidation ability and the latter mainly considered the existence form of Beijing SO42-/NO3- under the regional transport impacts.Finally,secondary oxidation ratios were estimated through combining secondary conversion contribution coefficients for simulated and monitored concentrations.At regional level,sulfur oxidation ratios in polluted(clean)days during two sampling periods were0.57–0.72(0.07–0.52)and 0.74–0.80(0.08–0.61),nitrogen oxidation ratios were 0.20–0.29(0.05–0.15)and 0.34–0.38(0.02–0.29),indicating that atmospheric oxidation was enhanced when considering regional transport through 2014–2017.At the local level,sulfur oxidation ratios were 0.66–0.71(0.04–0.48)in haze(clean)days,while nitrogen oxidation ratios were0.16–0.29(0.02–0.16).The atmospheric oxidation ability markedly increased in PM2.5pollution days,but changed only slightly between the two periods. 展开更多
关键词 HAZE PERIODS SO42- and NO3- SECONDARY CONVERSION SECONDARY oxidation ratio
Feasibility of aluminum recovery and MgAl2O4 spinel synthesis from secondary aluminum dross 预览
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作者 Yong Zhang Zhao-hui Guo +2 位作者 Zi-yu Han Xi-yuan Xiao Chi Peng 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期309-318,共10页
The feasibility of aluminum recovery from secondary aluminum dross by extraction with NaOH solution and the subsequent synthesis of MgAl2O4 spinel by sintering the extracted slag were studied. The extraction percentag... The feasibility of aluminum recovery from secondary aluminum dross by extraction with NaOH solution and the subsequent synthesis of MgAl2O4 spinel by sintering the extracted slag were studied. The extraction percentage of soluble aluminum from the dross reached 80% at a temperature of 353 K, liquid-to-solid ratio of 12 mL·g^-1, stirring speed of 300 r·min^-1, and an extraction time of 15 min;the hydrolysis percentage of AlN reached 40% with an extraction time of 30 min. The activation energies of the soluble aluminum and AlN extracted from the dross were 7.15 and 8.98 kJ·mol^-1, respectively, indicating that their kinetics were controlled by outer diffusion without a product layer. The extracted slag was sintered in the temperature range 1373–1773 K;MgAl2O4 spinel with a compressive strength as high as 69.4 MPa was produced in the sample sintered at 1673 K for 3 h. This value exceeds the threshold (40 MPa) prescribed by the National Standard for the Magnesia and Magnesia-alumina Refractory Bricks of China (GB/T 2275?2007). These results establish the effectiveness of aluminum recovery from secondary aluminum dross and subsequent MgAl2O4 spinel synthesis. 展开更多
关键词 SECONDARY ALUMINUM DROSS reuse extraction sintering magnesium ALUMINATE SPINEL
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微课在中职实训课教学中的应用探讨 预览
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作者 朱良 《现代职业教育》 2019年第8期224-225,共2页
微课教学模式近年来在实际教学中应用越来越广。针对中职实训课教学来说,使用微课十分符合课程特点和教学需要,同时也能有效提高学生自主学习的能力和对专业技能的理解能力。论述微课在中职实训课程中的意义、应用、产生的效果及在应用... 微课教学模式近年来在实际教学中应用越来越广。针对中职实训课教学来说,使用微课十分符合课程特点和教学需要,同时也能有效提高学生自主学习的能力和对专业技能的理解能力。论述微课在中职实训课程中的意义、应用、产生的效果及在应用中要注意的问题。 展开更多
关键词 微课 中职 实训课程
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继发性肺弥漫大B细胞淋巴瘤误诊为肺癌9例临床分析 预览
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作者 张祥娥 黄颂平 《中国临床新医学》 2019年第1期62-65,共4页
目的探讨误诊为肺癌的继发性肺弥漫大B细胞淋巴瘤(SPDLBCL)的临床特点和误诊原因。方法对收治的9例初诊为肺癌,后经病理确诊的SPDLBCL患者的临床资料进行回顾性分析。结果9例患者中,男女比例为5∶4。既往否认吸烟史。6例既往无免疫系统... 目的探讨误诊为肺癌的继发性肺弥漫大B细胞淋巴瘤(SPDLBCL)的临床特点和误诊原因。方法对收治的9例初诊为肺癌,后经病理确诊的SPDLBCL患者的临床资料进行回顾性分析。结果9例患者中,男女比例为5∶4。既往否认吸烟史。6例既往无免疫系统疾病。主要症状为咳嗽、咳痰、发热、气喘、胸痛、声音嘶哑,主要体征为浅表淋巴结肿大,呼吸音减低及肺部湿性啰音。实验室检查6例外周血淋巴细胞计数下降,8例乳酸脱氢酶(LDH)升高。CT发现肺部肿块7例(1例多发),6例可见周围磨玻璃影,3例可见支气管狭窄,3例可见胸腔积液,6例可见肺门、纵隔淋巴结肿大;多发结节2例,位于双肺,1例可见肺门、纵隔淋巴结肿大。7例行增强CT检查,1例未见强化,1例明显强化,1例轻度强化,4例不均匀强化。确诊方式:4例行淋巴结活检,3例行CT引导下肺穿刺,2例行气管镜,经病理结合免疫组化确诊为SPDLBCL。结论SPDLBCL临床少见,临床和影像学缺乏特异性,极易误诊。当患者血LDH升高,而CT检查肺内结节肿块边缘不规则,不均匀强化,伴周围磨玻璃影的出现,提示SPDLBCL可能,最终确诊需结合病理及免疫组织化学检查。 展开更多
关键词 弥漫大B细胞淋巴瘤 肺肿瘤 继发性 误诊
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The Effects of Secondary Metabolites of Rangeland and Pasture Plants on the Animal Health in Mediterranean Ecological Conditions 预览
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作者 Emre Kara Mustafa Sürmen 《美中医学:英文版》 2019年第2期63-72,共10页
Grazed areas including rangelands and pastures cover approximately 51%of the Earth’s continental surface.The plant species which are in these areas which form a wide biodiversity with living and non-living organisims... Grazed areas including rangelands and pastures cover approximately 51%of the Earth’s continental surface.The plant species which are in these areas which form a wide biodiversity with living and non-living organisims,stand out with both as a forage source and medical use.In this natural habitat,plants are surrounded by a large number of potential enemies.Since plants are not able to escape from these enemies(herbivores and pathogenes),plants produce substances which are not functional for growing and develop but protect plants against external factors as defence mechanisms.These substances are called secondary metabolites.These substances which are seen differently from the primer metabolites,possess charachteristics specific to each plant species.Secondary metabolites of plant origin can be divided into three main groups as terpens,phenolic compounds and nitrogenous compounds.Terpenes have negative effects on many mammals and insects,because they are toxic.The lignin,a phenolic compound,is located in the plant cell wall and has a particularly digestibility-lowering effect.In addition,flavanoids,which are again phenolic compounds,are thought to be produced against harmful effects of UV rays and pathogen invasion.Tannins,another phenolic compounds,are generally toxic.When plants which have tannins are grazed by herbivorous,they significantly reduce chances of growth and survival of animals.Finally,the alkaloids which are in the nitrogenous secondary products,are seen in a very wide area.These metabolites,especially in invasive plants that are heavily exposed to heavy grazing rangelands and pastures,affect the nervous system in livestock and can cause paralysis and even sudden deaths These three secondary metabolite groups are also commonly found in plants that are not properly managed in the meadow and pasture areas of the Mediterranean climate zone and can cause economic damage by affecting animal health and quality of animal products,especially in areas where animal production is seen.However,these economic lo 展开更多
关键词 RANGELAND SECONDARY METABOLITES TOXIC PLANTS ANIMAL health.
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Effect of Heat Treatment on Microstructure and Stress Rupture Properties of a Ni–Mo–Cr–Fe Base Corrosion-Resistant Superalloy
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作者 Tao Liu Mei Yang +3 位作者 Jun-Song Wang Jia-Sheng Dong Li Wang Lang-Hong Lou 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期116-126,共11页
The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni–Mo–Cr–Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope ... The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni–Mo–Cr–Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope and scanning electron microscope were employed for the microstructure observation, and X-ray diffraction, electron probe micro-analyzer, and transmission electron microscope were used for phase determination. It was found that the grain size increased and the volume fractions of initial M6C carbides decreased along with the increase in solution treatment temperature. When tested at 650 °C/320 MPa, the stress rupture lives decreased with the increase in solution treatment temperature, but the stress rupture lives increased slightly at first and then decreased for the samples solution heat treated at 1220 °C when tested at 700 °C/240 MPa. The elongations showed the descendent trends under these two conditions. The stress rupture life and elongation for the aged samples all showed a noticeable improvement at 650 °C/320 MPa, but there was no noticeable improvement at 700 °C/240 MPa. The reasons can be attributed to the grain size, test conditions, and the initial and secondary carbides. 展开更多
关键词 Corrosion-resistant SUPERALLOY Heat treatment Stress RUPTURE properties SECONDARY carbides
术中甲状旁腺激素测定在甲状旁腺切除中应用
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作者 陈安举 徐先发 《国际耳鼻咽喉头颈外科杂志》 2019年第1期23-26,31共5页
人体甲状旁腺合成和分泌甲状旁腺激素,甲状旁腺激素作用于骨骼和肾脏,从而调节血钙水平。甲状旁腺自身病变或其他疾病引起钙磷紊乱,导致甲状旁腺过度分泌甲状旁腺激素引起甲状旁腺功能亢进。继发性甲状旁腺功能亢进是慢性肾脏病患者的... 人体甲状旁腺合成和分泌甲状旁腺激素,甲状旁腺激素作用于骨骼和肾脏,从而调节血钙水平。甲状旁腺自身病变或其他疾病引起钙磷紊乱,导致甲状旁腺过度分泌甲状旁腺激素引起甲状旁腺功能亢进。继发性甲状旁腺功能亢进是慢性肾脏病患者的常见并发症之一,引起钙磷代谢失调、骨组织病变等一系列临床症状。对于难治性继发性甲状旁腺亢进,甲状旁腺切除术是主要的治疗手段。术中甲状旁腺激素测定是甲状旁腺手术过程中的一种功能性诊断工具,可以预测手术成功与否,并帮助术者决定是否需要进一步的探查,从而减少不必要的探查所导致的手术并发症。 展开更多
关键词 甲状旁腺 甲状旁腺功能亢进症 继发陛 甲状旁腺切除术 甲状旁腺激素
继发性甲状旁腺功能亢进不同手术方式的疗效分析
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作者 李会政 刘琳 张颖 《中国耳鼻咽喉头颈外科》 CSCD 2019年第2期59-62,共4页
目的分析比较甲状旁腺次全切除术和甲状旁腺全切+前臂自体移植术对于治疗尿毒症继发性甲状旁腺功能亢进的临床疗效。方法回顾性分析2012年1月~2018年6月在大连市友谊医院行手术治疗的继发性甲状旁腺功能亢进患者资料31例。病例分为2组,... 目的分析比较甲状旁腺次全切除术和甲状旁腺全切+前臂自体移植术对于治疗尿毒症继发性甲状旁腺功能亢进的临床疗效。方法回顾性分析2012年1月~2018年6月在大连市友谊医院行手术治疗的继发性甲状旁腺功能亢进患者资料31例。病例分为2组,Ⅰ组行甲状旁腺次全切除术(20例),Ⅱ组行甲状旁腺全切+前臂自体移植术(11例)。对患者术前,术后1周、1、3、6个月血钙、血磷、血PTH水平、临床症状改善程度等资料进行分析。结果术后血钙、血磷、血i PTH均较术前明显下降,差异有统计学意义(P<0.05)。两组间术前、术后血钙、血磷及术后6个月血iPTH的水平差异不大,无统计学意义(P>0.05)。两组患者术后骨痛、皮肤瘙痒、不安腿综合征均得到明显改善,两组间症状减轻程度差异无统计学意义(P>0.05)。结论两种术式均能有效治疗尿毒症继发性甲状旁腺功能亢进,手术安全性高,两组对血钙、血磷的影响无明显差异,全切+前臂自体移植组短期内甲状旁腺激素下降更加明显。二者均存在复发的可能性,全切+前臂自体移植术二次手术简便易行,具有一定的优势。 展开更多
关键词 甲状旁腺功能亢进症 继发性 疗效比较研究 外科手术 甲状旁腺次全切除术
A zinc(Ⅱ) MOF based on secondary building units of infinite wavy-shaped chain exhibiting obvious luminescent sense effects
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作者 Kai Li Kunhuan He +3 位作者 Quanwen Li Bin Xia Qinglun Wang Yinghui Zhang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期499-501,共3页
A new metal-organic framework (MOF),{[Zn7 (BPS)4 (OH)6 (H2O)2]·5 H2O]n}(1), (H2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthesized un... A new metal-organic framework (MOF),{[Zn7 (BPS)4 (OH)6 (H2O)2]·5 H2O]n}(1), (H2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction and further confirmed by PXRD, TGA and IR spectrum. The solid-state emission spectra reveal that compound 1 presents strong luminescence emission bands at room temperature. The fluorescent properties of compound 1 in diverse organic solvents indicated that 1 has palpable luminescent sense effects for DMF and DMAC. 展开更多
关键词 METAL-ORGANIC frameworks Secondary building unit SOLID-STATE emission spectra Fluorescent properties LUMINESCENT SENSE EFFECTS
Study on volt-ampere characteristics of solar array arcs in LEO spacecraft
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作者 朱立颖 刘治钢 +3 位作者 张晓峰 王超 李小飞 赵冰欣 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第2期39-46,共8页
The primary and secondary arcs volt-ampere characteristics of low earth orbit solar arrays are studied in this research. Using three gallium-arsenide solar cell samples, the gap lengths of the solar cell are set to 1,... The primary and secondary arcs volt-ampere characteristics of low earth orbit solar arrays are studied in this research. Using three gallium-arsenide solar cell samples, the gap lengths of the solar cell are set to 1, 2, and 3 mm. First, the primary arc voltage characteristics of a solar array are analyzed. It is found that two steps are involved in the primary arc voltages, which are 116 and 22 V according to our experiment and are independent of the electrostatic discharge current and the gap lengths. By comparing with the arc pattern, we determined that current chopping may be the reason for the stepped arc voltage. Then, the characteristics of the secondary arc of the solar array are demonstrated. The study shows that the secondary arc voltage values increase with the gap length. In the case of the same cell with a fixed gap length, the voltage of the secondary arc increases with the string current. Finally, the relationship between the secondary arc voltage and the gap length is obtained which helps the string voltage and the gap length selection for system design. 展开更多
关键词 primary ARC SECONDARY ARC solar ARRAY
Outcomes of secondary sulcus intraocular lens implantation in unilateral anterior persistent fetal vasculature
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作者 Jing-Hua Liu Song-Feng Li +2 位作者 Guang-Da Deng Yong-Hong Jiao Hai Lu 《国际眼科杂志:英文版》 SCIE CAS 2019年第4期592-596,共5页
AIM: To evaluate the surgical results of sulcus intraocular lens (IOL) implantation in children with unilateral anterior persistent fetal vasculature (PFV) underwent primary vitrectomy combined with lensectomy and pre... AIM: To evaluate the surgical results of sulcus intraocular lens (IOL) implantation in children with unilateral anterior persistent fetal vasculature (PFV) underwent primary vitrectomy combined with lensectomy and preservation of the peripheral anterior capsule. METHODS: Twenty-two eyes of 22 children with unilateral anterior PFV who underwent sulcus secondary IOL implantation were analyzed. Main outcome measures were preoperative and postoperative visual acuity, and complications both intraoperatively and postoperatively. RESULTS: Review of 22 consecutive patients identified best-corrected visual acuity (BCVA) improvement from 1.37±0.84 to 0.73±0.57 logarithm of the minimal angle of resolution (logMAR) after IOL implantation (P<0.001) with a mean follow-up was 16.55±5.86mo. Average age at secondary IOL implantation was 41.05±15.41mo. Three eyes (13.64%) achieved BCVA of 0.3 logMAR at the final visit. Transient intraocular pressure rise (4 eyes;18.18%), postoperative increased inflammation (3 eyes;13.64%) and postoperative hypotony (2 eyes;9.09%) were common complications. CONCLUSION: Properly preservation of the anterior lens capsule during the primary surgery facilitated secondary sulcus IOL implantation in pediatric patients with anterior PFV, with favorable postoperative visual outcomes and compatible percentage of complications. 展开更多
关键词 SECONDARY SULCUS INTRAOCULAR lens implantation SULCUS PERSISTENT FETAL VASCULATURE
Fujita-type Phenomenon of the Nonlocal Diffusion Equations with Localized Source
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作者 Lili YANG Zhongping LI 《数学研究及应用:英文版》 CSCD 2019年第2期171-180,共10页
In this paper, we investigate the Cauchy problem for the nonlocal diffusion system with localized source ut = J*u-u + a(x)v~p, v_t = J*v-v + a(x)u~q. We first prove that the Fujita curve is(pq)_c*-= 1+max{p+1, q+1}bas... In this paper, we investigate the Cauchy problem for the nonlocal diffusion system with localized source ut = J*u-u + a(x)v~p, v_t = J*v-v + a(x)u~q. We first prove that the Fujita curve is(pq)_c*-= 1+max{p+1, q+1}based on whether there exist global solutions, thatis, if 1 < pq(pq)_c,then every nonnegative solution blows up in finite time, but for pq >(pq)_c,there exist both global and non-global solutions to the problem. Furthermore, we establish the secondary critical curve on the space-decay of initial value at infinity. 展开更多
关键词 NONLOCAL diffusion system Fujita CRITICAL CURVE secondary CRITICAL CURVE global EXISTENCE BLOW-UP
Algicidal activities of secondary metabolites of marine macroalgal-derived endophytic fungi 预览
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作者 MIAO Fengping ZUO Jincheng +1 位作者 LIU Xianghong JI Naiyun 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期112-121,共10页
Red tide occurrs frequently and causes signifi cant damage to the environment and human health.As a result,development of new effi cient and environment friendly red-tide microalgae inhibitors has gained increasing at... Red tide occurrs frequently and causes signifi cant damage to the environment and human health.As a result,development of new effi cient and environment friendly red-tide microalgae inhibitors has gained increasing attention in recent times.Algicolous endophytic fungi with unique habitats are promising sources for active agents owing to their abundant secondary metabolites and distinguished activities.In this study,the algicidal activities of 49 marine macroalgal-derived endophytic fungi against phytoplankton Alexandrium tamarense,Prorocentrum donghaiense,Heterosigma akashiwo,and Chattonella marina were examined using 96-well microplate.Four fungal strains,including Aspergillus wentii(pt-1),A.ustus(cf-42),and A.versicolor(dl-29,pt-20),exhibited potent algicidal activities.A total of 32 pure compounds isolated from these fungi were noted to possess diff erent degrees of algicidal activities.Of those,11 compounds comprising fi ve anthraquinones,two terpenoids,and four steroids showed high 24-h inhibition rates for the four red tide algae,with 24 h EC 50 values ranging from 0.01 to 14.29μg/mL.Among them,compound 1(1,5-dihydroxy-3-methoxy-7-methylanthraquinone)presented the strongest activity against H.akashiwo,and could decrease its chlorophyll a(Chl a)and superoxide dismutase contents and increase the soluble protein,malondialdehyde,and peroxidase contents.These results suggested that the identifi ed anti-algal compound might inhibit the growth of red tide algae by weakening photosynthesis(reducing Chl a content),destroying cell membrane,and damaging the antioxidant system. 展开更多
关键词 algicidal activity ENDOPHYTIC FUNGUS SECONDARY METABOLITE MARINE ALGA
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Comparison of water quality in two catchments with different forest types in the headwater region of the Hun River,Northeast China 预览
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作者 Jiao-jun Zhu Li-zhong Yu +2 位作者 Tian-le Xu Xiaohua Wei Kai Yang 《林业研究:英文版》 CAS CSCD 2019年第2期565-576,共12页
In the headwater catchments of the Hun River,Northeast China,secondary forests(SF)have been replaced by plantations since the 1960s.Concern has been growing over this loss and the decline in water quality caused by th... In the headwater catchments of the Hun River,Northeast China,secondary forests(SF)have been replaced by plantations since the 1960s.Concern has been growing over this loss and the decline in water quality caused by the plantations.To test the effects of plantations on water quality,we selected two separate catchments covered by SF and Pinus koraiensis plantations(KP)to monitor physical and chemical properties of various hydrological variables including throughfall,stemflow,through-litterfall and runoff(flowing out of outlets of the catchments).The physical properties of water declined after water flowed through the two catchments as compared with rainwater.The pH of runoff in both catchments also dramatically decreased.The concentrations of Cl^-,NO3^-and NH4^+in the runoff from the two catchments were similar(concentrations of Cl^-and NH4^+in both catchments were similar to those in rainwater).Total P concentration in runoff of the SF catchment was higher than that of the KP catchment(P concentrations in both catchments were also higher than in rainwater)because P concentrations in litter and soil of the SF catchment were higher than those in the KP catchment.In summary,the rainwater became acidic in both catchments,but the responses of most water quality variables were similar in the two catchments,suggesting that appropriate ratios of KP in SF are feasible for secondary forest recovery and for preserving water quality(KP did not cause a decline in quality)in the headstream regions in Northeast of China. 展开更多
关键词 Forested CATCHMENTS SECONDARY FORESTS Plantations Water quality
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CDA Application in Secondary ESL Class in Western China
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作者 潘梦来 《海外英语》 2019年第4期250-252,共3页
English as second language(ESL)theoretical studies and practice have witnessed great development in recent years in China with more schools diversifying the forms and contents of English classes over the last decade.A... English as second language(ESL)theoretical studies and practice have witnessed great development in recent years in China with more schools diversifying the forms and contents of English classes over the last decade.After these years development,however,studies on ESL teaching in China,especially western China where teaching quality is relatively low and teaching resources are not sufficient lags behind that in some other developed countries though some progress has been made.Students’capability on essential discourse analysis has not gained deserved attention.This article intends to introduce critical discourse analysis(CDA),a tool to explore discourse and social relations to secondary ESL class in western China in an attempt to find a new channel to improve students’learning effects and teaching quality of the region. 展开更多
关键词 CDA SECONDARY ESL CLASS WESTERN China
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肺癌骨转移患者血清和转移灶中LCN2和PDGF-BB的检测及意义 预览
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作者 曹亚男 李晶晶 +5 位作者 张航 高聪 董翔 任鹏飞 孟晨旭 李烦繁 《临床与实验病理学杂志》 CAS CSCD 北大核心 2019年第2期187-191,共5页
目的探讨脂质运载蛋白2(lipocalin-2,LCN2)和血小板衍生生长因子BB(platelet derived growth factor-BB,PDGF-BB)在肺癌患者血清、癌组织和骨转移灶中的表达。方法应用蛋白芯片筛选19例(9例仅发生骨转移和10例无远处转移)肺癌患者血清... 目的探讨脂质运载蛋白2(lipocalin-2,LCN2)和血小板衍生生长因子BB(platelet derived growth factor-BB,PDGF-BB)在肺癌患者血清、癌组织和骨转移灶中的表达。方法应用蛋白芯片筛选19例(9例仅发生骨转移和10例无远处转移)肺癌患者血清中差异表达的细胞因子;采用免疫组化法检测12例无远处转移的肺癌原发灶和12例仅发生骨转移的骨转移灶中LCN2和PDGF-BB因子的表达。结果非小细胞肺癌患者血清中LCN2和PDGF-BB在骨转移组中的表达明显高于无远处转移组(P <0. 05);小细胞肺癌患者血清中未检测到差异表达的细胞因子(P> 0. 05)。免疫组化结果显示LCN2和PDGF-BB在非小细胞肺癌患者骨转移灶中呈高表达,高于肺癌原发灶组织(P <0. 05)。结论 LCN2、PDGF-BB在非小细胞肺癌骨转移患者血清及骨转移灶中高表达,可能在骨髓微环境中参与肺癌骨转移的发生、发展,有望成为肺癌骨转移的重要检测指标和潜在治疗靶点。 展开更多
关键词 肺肿瘤 非小细胞肺癌 继发性 LCN2 PDGF-BB
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Chitosan tubes enriched with fresh skeletal muscle fibers for delayed repair of peripheral nerve defects 预览
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作者 Alessandro Crosio Benedetta Elena Fornasari +5 位作者 Giovanna Gambarotta Stefano Geuna Stefania Raimondo Bruno Battiston Pierluigi Tos Giulia Ronchi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期1079-1084,共6页
Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump... Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump of chronically transected nerves;moreover,Schwann cells undergo atrophy,losing their ability to sustain regeneration.In the present study,to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth,we combined the use of an effective conduit(a chitosan tube)with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers).This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction.Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft,considered the“gold standard”technique for nerve reconstruction.Since hollow tubes not always lead to good results after long defects(>20 mm),we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps,as muscle fibers create a favorable three-dimensional environment and release trophic factors.All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number:864/2016/PR)on September 14,2016. 展开更多
关键词 tubulization Schwann cells SCAFFOLD tissue engineering NERVE reconstruction morphometrical analyses GRASPING test secondary repair MEDIAN NERVE NERVE REGENERATION
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Biomass increment and mortality losses in tropical secondary forests of Hainan,China 预览
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作者 Junfu Zhao Chunsheng He +6 位作者 Chunlin Qi Xu Wang Haiyan Deng Chunxin Wang Haiwei Liu Lianyan Yang Zhenghong Tan 《林业研究:英文版》 CAS CSCD 2019年第2期647-655,共9页
Secondary forests,created after heavy logging,are an important part of China’s forests.We investigated forest biomass and its accumulation rate in 38 plots in a tropical secondary forest on Hainan Island.These second... Secondary forests,created after heavy logging,are an important part of China’s forests.We investigated forest biomass and its accumulation rate in 38 plots in a tropical secondary forest on Hainan Island.These secondary forests are moderate carbon sinks,averaging 1.96–2.17 t C ha^-1 a^-1.Biomass increment is largely by medium-sized(10–35 m)trees.Tree mortality accounts for almost 30%of the biomass and plays a negligible role in biomass accumulation estimates.Mortality rate is highly dependent on tree size.For small trees and seedlings,it is related to competition due to elevated irradiance after logging.Regarding prospective biomass and rates of accumulation,recovery is not as rapid as in secondary forests of cleared land.Therefore,tropical forests are susceptible to logging operations and need careful forest management. 展开更多
关键词 Tropical secondary forest management Carbon SINK Inventory Dynamic PLOT LOGGING
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Under Osmotic Stress with PEG 预览
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作者 Jinhua LIU Qian LIU +1 位作者 Jia LI Yongqing ZHANG 《农业生物技术:英文版》 CAS 2019年第1期57-60,共4页
[Objectives]This study was conducted to study the Germination characteristics and secondary metabolism regulation of Scutellaria baicalensis Georgi under osmotic stress.[Methods]The activity of praline,soluble sugar a... [Objectives]This study was conducted to study the Germination characteristics and secondary metabolism regulation of Scutellaria baicalensis Georgi under osmotic stress.[Methods]The activity of praline,soluble sugar and protein was detected with ultraviolet spectrophotometry.The activity of phenylalanine ammonia-lyase(PAL)and cinnamic acid 4-hydroxylase(C 4H)was determined with ultraviolet spectrophotometry.The secondary metabolites were detected by high performance liquid chromatography(HPLC).[Results]The germination percentage,germination potentiality and germination index decreased at first and increased subsequently along with the enhancement of PEG concentration.The praline content,the soluble sugar content and the soluble protein content in S.baicalensis seedlings increased along with the enhancement of PEG concentration and the differences from the CK were significant(P<0.05).The PAL and C 4H in S.baicalensis seedlings decreased after osmotic stress and the differences from the CK were significant(P<0.05).The results indicate that,the scutellarin,baicalin,wogonoside,baicalein,wogonin and oroxylinA contents decreased after osmotic stress and the differences from the CK were significant(P<0.05).[Conclusions]The quality of the skullcaps could be improved by improving the activity of PAL and C 4H. 展开更多
关键词 GERMINATION characteristics PAL C 4H SECONDARY METABOLITES
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SPECT/CT融合显像在继发性甲状旁腺功能亢进症中的临床价值 预览
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作者 陈正国 刘启榆 +2 位作者 吴春燕 陈娇 何川东 《中国临床医学影像杂志》 CAS 2019年第3期169-173,共5页
目的:探讨术前99m Tc-甲氧异腈(MIBI)核素双时相显像与SPECT/CT融合显像在继发性甲状旁腺功能亢进症中的临床价值。方法:回顾分析经病理证实的38例继发性甲状旁腺功能亢进症患者术前99m Tc-MIBI核素双时相显像与SPECT/CT融合显像的影像... 目的:探讨术前99m Tc-甲氧异腈(MIBI)核素双时相显像与SPECT/CT融合显像在继发性甲状旁腺功能亢进症中的临床价值。方法:回顾分析经病理证实的38例继发性甲状旁腺功能亢进症患者术前99m Tc-MIBI核素双时相显像与SPECT/CT融合显像的影像资料。结果:99m Tc-MIBI核素双时相显像与SPECT/CT融合显像诊断继发性甲状旁腺功能亢进症的灵敏度分别为86.52%、95.74%;统计分析显示两者之间差异有统计学意义。结论:术前99m Tc-MIBI核素SPECT/CT融合显像对继发性甲状旁腺功能亢进症的评估优于核素双时相显像,SPECT/CT融合显像是继发性甲状旁腺功能亢进症术前定位理想的检查方法。 展开更多
关键词 甲状旁腺功能亢进症 继发性 99M锝甲氧基异丁基异腈 体层摄影术 发射型计算机 单光子
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