1. Introduction

Many therapeutic agents are used in medicine against diseases and different plants comprise of the sources of these compounds[1,2].In fact, according to Pan et al.[2], more than 35000 species of plants possess curative potentials because of their phytochemical constituents. These chemical constituents are functionally classified as primary and secondary metabolites. Primary metabolites, essential for development, growth and reproduction of plant, are proteins,lipids, nucleic acids and carbohydrates. Secondary metabolites,produced in response to the involvement of plant with the environment or as possible defensive mechanisms against aggressive agents, can be represented by many compounds as alkaloids, flavonoids and terpenoids[3].

Most of the commercially available drugs are derived from plants or generated from natural products. Some compounds of plant and/or derived from plant were discovered throughout history. Among these compounds, we can find capsaicin (Capsicum spp.), aspirin (Salix alba L.), atropin (Atropa belladonna), morphine (Papaver somniferum L.), quinine (Cinchona sp.), pilocarpine (Pilocarpus jaborandi and Pilocarpus microphyllus), colchinine (Colchicum autumnale),etoposide (Podophyllum peltatum L.), masoprocol (Larrea divaricata Cav.), metformin (Galega officinalis), levodopa (Mucuna pruriens),dicumarol (Melilotus officinalis), vinblastine, vincristine, vinrosidine,vinorelbine and vinflunine (Catharanthus roseus), solamargine(Solanumdu lcamara), taxol (Taxus brevifolia), artemisinin (Artemisia annua), maytansine (Maytenus ovatus), irinotecan (Camptotheca acuminata), and arglabin (Artemisia glabella Kar.)[4-30]

Currently, about 80% of the immunosuppressive, cardiovascular,antimicrobial and antitumor drugs are originated from plants. The identification and isolation of compounds and/or phytochemical groups are crucial for the discovery of new therapies[1,2,31-33].

Tithonia diversifolia (T. diversifolia) (Hemsl) A. Gray, is a perennial and shrub species of the family Asteraceae, tribe Heliantheae, which is native in Central America and Mexico and popularly known as Mexican sunflower[34-36]. Many representatives of this species are found throughout the world, especially in Asia, Africa and America[35].

In the literature, T. diversifolia is described as an important source of biologically active molecules[35], which possesses many compounds in leaves and inflorescences belonging to sesquiterpene lactones and flavonoids classes, and derivatives of trans-cinnamic acid[37,38].Extracts and secondary metabolites isolated from in florescences and leaves showed significant biological properties, such as antitumor[39],anti-in flammatory[37], antihyperglycemic[40] and antimicrobial[41].

周内尿素连续小幅探涨为市场带来新的操作思路，业内谨慎心态渐感释怀，只是追涨的意愿有限，一旦价格继续探涨，下游需求或将被再度刺激。客观分析全国52%左右的开工率确为高价尿素的保障条件。目前，虽尿素外贸因瓶颈无从谈起，但内需方面却渐被业内认可。预计下周国内尿素主产区出厂报价1900-1950元/吨。

In this study we explore the phytochemical characterization as well as investigate antioxidant profile, antimicrobial properties against pathogenic species of bacteria and Candida sp. and cytotoxicity against mice splenocytes promoted by saline extract of T. diversifolia leaves.

2. Materials and methods

2.1. Processing of plant leaves and extract preparation

The plant was collected in city of Paudalho, interior of the State of Pernambuco, Brazil. The botanical identification was carried by Herbarium Geraldo Mariz of the Center of Biosciences of the Federal University of Pernambuco. Plant was deposited, under identification number 82.703. For two days, the humidity was removed for obtainment of dried leaves. These leaves were crushed in reverse black oster and the pulverized material (20 g) was diluted in 200 mL of NaCl (0.15 M/10% (w/v). Therefore, using an orbital and alternative incubator shaker (Lab Companion™ IS-971) the material was kept under agitation (400 rpm) in constant temperature(28 ℃) for 16 hours. After the stirring time, the material was filtered using paper filter and centrifuged (15 min, 10000 × g). The obtained supernatant was collected and called saline extract from T.diversifolia leaves. After this, the extract was lyophilized, and 9.2 g of crude material was obtained.

2.2. Phytochemical bioprospecting

2.2.1. Determination of total phenolic compounds

The contents of total phenols were determined through method described by Li et al.[42] with few modifications. One mg/mL of diluted extract was dissolved in distilled water. A total of 100 μL of Folin solution (1:10 v/v) was added to 200 μL of this diluted extract.After incubation, the extracts were protected from light for 3 min,and 0.08 mL of Na2CO3 (7.5%) was added. Extracts were then incubated again and protected from light, at 21 ℃, for 120 min. After incubation time, the extracts were read in the spectrophotometer(765 nm). Distilled water was the blank on the calibration curve. A calibration curve of the graphical representation of the absorbance as a function of the concentration of gallic acid (0-500 μg/mL) was prepared and the linear equation (Y = 0.004 8x + 0.="1>, R2² =0.9999). Phenols were indicated in gallic acid equivalent (mg GAE/g of extract).

2.2.2. Investigation of total flavonoids

The measurement of total flavonoid amount was performed similarly to the method used by Woisky and Salatino[43], with some modifications. Using test tubes, 1 mL of the extract, previously diluted (1 mg/mL) was added. After this, 1 mL of the 3% solution of aluminum chloride (AlCl3) prepared with methanol was added in tubes. After incubation (30 min), in dark (21 ℃), the absorbance was obtained (425 nm). A standard curve with quercetin (0-500 μg/mL)was performed to obtain the equation (Y = 0.023x + 0.1509, R2² =0.9956). The assays were obtained in quintuplicate. Flavonoids were indicated in quercetin equivalent (mg QE/g of extract).

2.2.3. Ultra-High Performance Liquid Chromatography coupled to Mass Spectrometry

Ultra-High Performance Liquid Chromatography was performed with an Acquity H-Class (Waters) employing a 2.1 mm × 100 mm BEH column with a particle size of 1.7 μm. The column was maintained under a constant temperature of 40 ℃ and the auto injector at 10 ℃. We used an aqueous solution (eluent A) containing 2% methanol (MeOH),5 mM ammonium formate and 0.1% formic acid and a methanol solution (eluent B) containing 0.1% formic acid, which were pumped at a flow rate of 0.3 mL/min. Ten microliters of the T. diversifolia extract was injected. Elution was performed in gradient mode and the initial condition (98% A / 2% B) was maintained for 0.25 min. The B ratio increased linearly to 99% in 8.5 min, remaining at 99% B for 1 min,followed by an immediate decrease to 2% B, where it was maintained for up to 11 min. The ultra-performance liquid chromatography system was coupled to a single quadrupole mass spectrometer SQ Detector 2(Waters). The data were obtained in fullscan mode, analyzing masses between 100 and 1000 Da, in negative ionization. The acquisition of the chromatograms and mass spectra was obtained through MassLynx™ software (Waters).

周贝利（2011）指出，真正的原儒所奉行的是一种具有高度人生智慧的依时变通的灵活处世原则，而非循规蹈矩的固定行为模式。同时，也正是这种主张因时、因事、因地、因势通权达变，反对泥古不化、僵守一端的理论张力，才使得儒学具备了与时具迁的生命力，而经权思想正是这种儒学生命力的集中体现。但也不应该忽视另一方面的内容，从总体上来看，经主权从、经贵权轻、经制约权、权服务于经是先秦儒家在经与权的关系上的共同旨归。

2.3. Antioxidant activities in vitro

2.3.1. Free radical sequestration by 2,2-diphenyl-1-picrylhydrazyl (DPPH·)

The antioxidant ability of saline extract was investigated through the stable radical DPPH·, as described by Blois[44]. We performed a serial dilution with 400 μL of the saline extract (3.9; 7.8; 15.6; 31.3;62.5; 125; 250 and 500 μg/mL). In each concentration was added 0.25 mL of the DPPH· solution (1 mM and OD517 = 0.650 ± 0.50).After incubation time (25 min/21 ℃/in the dark), the absorbance was obtained in 517 nm. The DPPH· solution added to water was used as control. The sequestration of DPPH· radicals was measured by using the equation:

《法制晚报》在刊发这条消息时，配了一幅漫画。画面中的两个人，正举着手机飞跑。其中一个一边跑一边说：“快点，还有5公里，走访还没有完成！”这真是可笑，在大街上跑步，就算是走访吗？而某些上边的考核者，看的只是行走的里程数字。至于你在哪里走，去干什么，全凭“指下生花”。

The chromatogram and mass spectrum of this extract (Figures 1 A and B, respectively) indicated the presence of important classes of biologically active compounds. Identified fifteen compounds were between terpenes and phenolics, based on retention time, peak area and mass characteristics (Table 1). Total phenol compounds and total flavonoids of saline extract from T. diversifolia leaves showed (22.185 ± 0.201) mg GAE/g and (3.220 ± 1.085) mg QE/g,respectively.

Where As is the sample absorbance and Ac is the control absorbance.

2.3.2. Total antioxidant activity

The stock solution of the FRAP assay was prepared using acetate buffer (300 mM / 16 mL of CH3COOH and 3.1 g of CH3COONa) at 3.6 pH, 10 mM TPTZ (2,4,6-tripyridyl-triazine) solubilized in FeCl3 solution (20 mM) and HCl (40 mM) as described by Benzie et al.[46].The assay solution was prepared by combination of the acetate buffer,TPTZ and FeCl3 in a ratio of 10:1:1 (v/v/v) and incubated for 5 min at 37 ℃. Saline extract (25 μL in 1 mg/mL) was added in 0.180 mL of FRAP solution. After stirring, the extract was rested for 30 min at 37 ℃, protected from light. Subsequently the absorbance was obtained at 593 nm. A standard curve with FeSO4 (0–1000 μg/mL)was performed to obtain the equation (Y = 0.002 4x + 0.as e, R2²=0.9953). The results were obtained as mg EFeSO4 (Ⅱ)/g of extract.

ATT (%) = [(As - Ac)/(Aaa - Ac)]×× 100.

Where Ac is the control absorbance, As is the sample absorbance and Aaa is the Ascorbic acid absorbance.

在产品方面，丝绸企业难以突破“丝绸即是面料”的限制，在设计、材料、工艺、包装、营销等方面，难以将丝绸的文化魅力全方位地展示出来。面对日益激烈的市场竞争，个别商家采取模仿、复制、抄袭等不良手段，“山寨”之风甚嚣尘上。囿于“仿制思维”，企业生产出大量类同化产品，难以面对消费者的求新心理和挑剔眼光。

2.3.3. FRAP assay

The authors declare no conflict of interest.

The total antioxidant activity of saline extract was measured as a function of ascorbic acid, according to Pietro et al.[45]. Saline extract(100 μL in 500 μg/mL) was mixed with ascorbic acid (1 mg/mL) and with 1 mL of phosphomolybdenum solution (600 mM sulfuric acid,28 mM sodium phosphate and 4 mM ammonium molybdate). This mixture was incubated in water bath (95 ℃ / 90 min). After cooling,the absorbance was obtained at 695 nm against a blank (1 mL solution with 0.1 mL of water). A standard curve with ascorbic acid(0-500 μg/mL) was performed to obtain the equation (Y = 0.019x +0.0723, R2 = 0.9937). The total antioxidant activity measured by the equation:

2.4. Antimicrobial activity test

2.4.1. Bacterial and fungal strains, culture conditions and preparation of samples

Fungal strains were obtained from the culture collections at Mycology Department from Federal University of Pernambuco and bacteria isolates were provided by the culture collection of the Departamento de Antibióticos da Universidade Federal de Pernambuco. Stock cultures were kept under refrigeration (-20 ℃) in sterilized skim milk containing 10% (v/v) glycerol. Microorganisms pathogens used in this investigation were Candida albicans (C.albicans), Candida krusei, Candida tropicalis, Candida parapsilosis (C.parapsilosis), Candida glabrata, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Salmonella enteritidis, Staphylococcus aureus and Staphylococcus saprophyticus. For antimicrobial activity assay, bacterial and yeast species were cultured in Mueller Hinton and Sabourand Dextrose agar medium, respectively, overnight at 36 ℃, and subsequently the colonies were resuspended in sterile saline solution (0.15M NaCl) and turbidimetrically adjusted at a wavelength of 600 nm (OD600) to obtain the suspension equivalent to 106 CFU/mL. For the assay, the samples were filtered on the sterile polyvinylidene difluoride syringe filter (pore size: 0.22 μm;diameter: 13 mm).

2.4.2. Determination of minimum inhibitory concentration(MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC)

The MIC of the leaf extract of T. diversifolia was determined by the microtiter test based on CLSI[47] criteria. In 96-well microtiter plates, the extract (12 mg/mL) was added (80 μL) into the fourth well from which a serial dilution in sterile Milli-Q water was performed to the twelfth well of the same row. Subsequently, 40 μL of Mueller Hinton (bacteria) or Sabourand Dextrose (yeast) broths were added to all wells, but to the first one was filled with 200 μL of the culture medium, corresponding thus to the sterility medium control. Antibiotics ampicillin and tetracycline (8 μg/mL) and antifungal fluconazole (64 μg/mL), obtained from Sigma-Aldrich(USA), were used as positive controls in the second well. Finally, the bacterial or yeast suspensions (80 μL, 106 CFU/mL) were added in the second well to the last well in the row. The third well (containing microorganisms in the absence of the sample) corresponded to the 100% growth control or negative control. The plates were incubated at 36 ℃ and the optical density was measured at time zero and after 24 h of incubation. The MIC90 and MIC50 corresponded to the lowest concentration of the sample capable of promoting a reduction of ≥90% or ≥50%, respectively, in optical density, as compared to the 100% growth control. For determination of the MBC and the MFC, aliquots of the wells containing concentrations of ≥MIC50 samples were inoculated into petri dishes containing Mueller Hinton or Sabourand Dextrose agar medium, which were subsequently incubated at 36 ℃ for 24 h. The MBC and MFC corresponded to the lower concentration of the sample which was able to reduce the number of CFU in 99.9% in relation to the initial inoculum. For this study, three independent experiments, performed in triplicate, were used.

Studies affirm that the species belonging to the Asteraceae family presents high concentrations of sesquiterpenes lactones[35,54] and also shows that compounds such as sesquiterpenes lactones, caffeinederived acids, diterpenes and flavonoids are commonly found in the aerial parts of T. diversifolia[38]. Our results demonstrated that, similar to other extracts from leaves of T. diversifolia (using different types of solvents), saline extract used in this study is rich in terpenoids and phenolics compounds[36,37,50,55,56]. In fact, Gama et al.[57] and Pantoja et al.[58] demonstrated higher antioxidant capacity promoted by ethanol extract of the in florescences of T. diversifolia which can be attributed to the phenols of this species. The phenolic compounds are agents that induce effectively to the antioxidant action due mainly to their reducing properties, which give them the ability to act as reducing agents, hydrogen and/or oxygen donors[59-61]. Our results also showed a similar profile of these studies, especially when compared to the commercial antioxidant BHT, when no significant difference between extract and standard was observed.

2.5. Obtainment of murine splenocytes for cytotoxicity assay

家长反映的看上去只是鸡毛蒜皮的小事，但确实折射出了我这个北方男人粗犷有余、细腻不足的一面，与其到校长室去投诉，不如给他们一个机会，直接向我提意见。于是，我把周末的周记改为命题作文：朱老师，我想对您说。为了让学生说真话，我要求周记必须从优点和不足两个方面来写。

Female BALB/c mice (6–8 weeks old) were obtained from the animal facilities of the Keizo Asami Immunopathology Laboratory–LIKA located in Federal University of Pernambuco, Brazil. Mice were kept under standard laboratory conditions (20–22 ℃/ 12 hours of day and night cycle / standard diet and water). All experimental procedures were performed in accordance with Ethics Committee of Animal Use of Federal University of Pernambuco, Brazil (protocol number: 0048 approved in December of 2016).

2.5.2. Preparation of splenocytes

This procedure was performed in accordance to Melo et al.[48].Cells of the spleens of mice were processed in polystyrene conic tubes (15 mL) with Ficoll-PaqueTM PLUS solution with the density adjusted to 1.076 g/mL. After three centrifugations, cells were counted in a Neubauer chamber, using the trypan blue solution. Cells were only used when viability was ＞95%.

2.5.3. Investigation of cell death

Mice splenocytes (106 cells) were treated with T. diversifolia saline extract in 50, 25, 12.5, 6 and 3 μg/mL and were maintained in 48-well plates for 24 h to evaluate the cytotoxicity power of the extract. Untreated cells, only in RPMI 1640 medium, were used as control. After this, lymphocytes were centrifuged twice at 26 ℃,450 × g for 10 min. The pellet was resuspended in a cytometer tube containing 300 μL of binding buffer of cell viability kit (Becton Dickinson Biosciences). Annexin Ⅴ-FITC (1:500) and propidium iodide-PE (20 μg/mL) were added to tube. Samples was obtained in FACSCalibur flow cytometer (BD®) and analyzed using Cell Quest Pro software (BD®).

2.5.4. Cell proliferation analysis

2.5.1. Animals

Same protocol to obtained splenocytes was used for proliferation assay. After splenocytes obtainment, cell solution was centrifuged at 300 × g (21 ℃/5 min) with sterile PBS 1X added with SFB 5%(pH 7.2). After this, the cell solution was adjusted to1×106 cells/mL and was incubated (for 10 min) with 5mM of 5(6)-carboxy fluorescein diacetate N-succinimidyl ester. Cells were centrifuged at 300 × g/5 min with sterile PBS 1××. Cells stained were cultured for 24 and 48 h with 12.5 μg/mL of saline extract from T. diversifolia leaves and only culture complete RPMI 1640 medium (negative control). After culture time cells were centrifuged (300 ××g/5 min), they were carried on FACSCalibur flow cytometer (BD®) and results were analyzed using Cell Quest Pro software (BD®).

2.6. Statistical analysis

Shapiro–Wilke test was applied to evaluate normal hypothesis. The statistical difference between two groups was analyzed by Wilcoxon test and among more than three groups by ANOVA. Significance level considered was 5%. GraphPad Prim 5.01 software was used in our statistical tests.

3. Results

3.1. Phytochemical analysis

DPPH· (%) = [(As - Ac)/Ac] × 100

3.2. Antioxidant activities in vitro

Results of antioxidant capacity promoted by saline extract of T.diversifolia leaves showed that the extract had an antioxidant capacity(3.042±0.019 mg AAE/g) similar to butylated hydroxytoluene (BHT)standard [(4.12±0.10) mg AAE/g]. The extract also promoted lowerfree radical sequestration [(10.11±1.15)% mg/mL; (93.13±0.58)%mg/mL; (90.04±0.16)% mg/mL, to saline extract, BHT and ascorbic acid, respectively] and was able to induce a reduction of ferric ion[(236.53±26.97) mg EFeSO4 (Ⅱ)/g; (679.17±25.98) mg EFeSO4 (Ⅱ)/g;(1215.00±48.55) mg EFeSO4 (Ⅱ)/g to saline extract, BHT and ascorbic acid, respectively].

3.3. Antimicrobial assay

The saline extract of T. diversifolia did not show antibacterial activity against bacterial isolates tested (data not shown). However, this compound demonstrated potential fungistatic and fungicidal properties in vitro against pathogenic species of Candida. Results showed that saline extract induced MIC50 in C. albicans (0.293 μg/mL), Candida krusei (0.0024 μg/mL) and C. parapsilosis (0.293 μg/mL). It also induced MIC90 in the above same fungal strains (0.293 μg/mL; 0.0048 μg/mL and 0.293 μg/mL, respectively) and MFC in C. albicans (150 μg/mL) and C. parapsilosis (0.375 μg/mL). Fluconazole, used as positive control, showed potential effects to all strains tested (except Candida tropicalis) and MIC50 values obtained were 0.25 μg/mL, 32 μg/mL, 4 μg/mL and 64 μg/mL to C. albicans, Candida krusei, C.parapsilosis and Candida glabrata, respectively.

3.4. Cell viability promoted by saline extract from T.diversifolia leaves

After the antimicrobial properties were evaluated, we performed a cytotoxicity test to investigate if saline extract from T. diversifolia leaves was able to kill mice splenocytes. For this test, cell cultures were treated with different concentrations of saline extract and results showed that this extract might be used with safety in concentrations equal to and lower than 25 μg/mL (Figure 2).Moreover, we evaluated if saline extract also was able to promote cell activation and proliferation in these cells. Our results showed that saline extract promoted splenocytes proliferation in higher values especially at 24 hours of assay (Figure 3).

高效准确的识别叶芽和花芽，才能够准确的运用各种修剪技术，提高冬剪的效率和质量，使树体合理负载，节约养分，有效克服树体大小年现象。

㉗高晓霞:《日本审计院》，载审计署审计科研所编《世界主要国家和国际组织审计概况》，中国时代经济出版社2014年版，第291页。

4. Discussion

T. diversifolia is commonly used in folk medicine in several continents[9] due to its phytomedicine and ethnopharmacological applicability in the treatment of various organic disturbances[49]. The extracts of T. diversifolia are used orally because of their analgesic capacity[50], antimalarial[51], antipyretic[52] and antidiabetic[53], and are topical applied by their anti-in flammatory potential[52] and in the treatment of microbial infections in the genitals organs[49].

2.1.6 酒炖熟地黄[4] 取生地黄，加入黄酒拌匀，闷润至酒吸尽，连续炖制48 h后（炖制24 h时，上下翻动1次），70 ℃干燥至熟地黄饮片的含水量不超15.0%时取出，放凉即得（100 kg生地黄用黄酒40 kg），即为样品熟地黄VI。

T. diversifolia species, as well as the entire Asteraceae family present high amounts of terpenoids, a natural compound with antimicrobial effects[37,38,54,62]. Several tests performed with extracts and compounds isolated from various tissues of T. diversifolia proved the potential antimicrobial capacity against many pathogenic species of bacteria and fungi[38,41].

However, we did not find results of antibacterial activity to our saline extract, but a significant antifungal action was observed. These results were reinforced by Ait-Ouazzou and collaborators[63] and Zengin and Baysal[64] that demonstrated that terpenoids compounds present in their preparations did not show in vitro inhibitory capacity against growth of the bacterial species. Moreover, Duraipandiyan et al.[62] demonstrated that two sesquisterpenic lactones (ostunolide and eremanthin) isolated from Costus speciosus (Asteraceae) were not be able to inhibit bacterial growth, but both compounds showed fungistatic properties. Assays with T. diversifolia, performed by Obafemi et al.[65] and Olayinka et al.[66], also demonstrated that ethanolic extracts, aqueous extracts, fractions and sesquiterpenic compound isolated from leaves, roots and stem, respectively,presented a potential antifungal activity against C. albicans.

Fluconazole is a potent antifungal agent in microbiology field for the treatment of candidiasis[67,68]. When we compare the fungistatic results observed from saline extract with those of fluconazole, it is indicated that the extract from T. diversifolia leaves also possesses antifungal potentials against Candida species.

Different plant extracts are indicated by traditional medicine for the treatment of viral[69-71], bacterial and fungal infections[72-75]. However,the misconception that natural products, besides not being toxic, also not possess side effects, induces the population to indiscriminate and inappropriate use, which in turn results in serious health problems, such as poisoning[76]. Many treatments, promoted by natural compounds,may be immunosuppressive or cause serious side effects[77,78]. Here we also investigated if saline extract, prepared using an usual physiological concentration (NaCl 0.15M), is dangerous to normal cells because many communities used T. diversifolia tea for some diseases[49,53].Our results showed that in appropriate dose, saline extract from T.diversifolia leaves is able to activate mice splenocytes and induce higher cell proliferation in these cells at 24 hours of assay, indicating a possible immunostimulant effect. Similar to our findings, other studies show that extracts from T. diversifolia leaves were able to promote the differentiation of mesenchymal stem cells[79] and did not promote cytotoxicity against human peripheral blood mononuclear cells and mouse macrophages[80].

In conclusion, saline extract from T. diversifolia leaves presented higher amounts of terpenoids and phenolics compounds, being suggestive of the presence of sesquisterpenes lactones. This extract showed antioxidant capacity, reduction of the ferric ion and antifungal properties against Candida species. Moreover, the extract promoted cell proliferation in mice splenocytes. These results indicate that, in future, saline extract from Tithonia diversifolia leaves can be investigated as a prototype candidate for antifungal agent and/or adjuvant of the antimicrobial conventional therapies.

Conflict of interest statement

3) 标准差椭圆及重心轨迹图表明：厦门市民宿聚集区为思明区，民宿分布大致经历了北→南→北→西北的回旋式演变，如今民宿分布的空间发展趋势是向西北—东南延伸，逐步向岛外扩展.

Acknowledgments

传统评价方式以某次考试或者单纯以卷面成绩作为评价学生的唯一标准，往往会打击学生的学习积极性，弊端日渐显现。因此，我们必须创新评价机制。针对学生爱玩和爱竞争的心理，在语文日常教学中，可借鉴游戏中的激励机制对学生进行评价。如在每天的学习中，学生背诵诗文、完成作业、主动回答问题等都可以作为考核内容，每完成一项，应给予相应的奖励分，每天有专人考核并公布考核结果，前三名要展示在教室光荣榜上，考核成绩日日更新，每月班级排行榜分为状元、榜眼、探花等不同级别，实践证明，这种评价机制极大地提高了学生的学习积极性。

The authors thank Nucleus of Technological Platforms (NPT-1)located at Aggeu Magalhães Institute (IAM).

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