Light Competition Contributes to the Death of Masson Pines of Coniferous-Broadleaf Mixed Forests in Subtropical China

In the process of subtropical forest succession, it has long been recognized that population decline of Masson pines in coniferous-broadleaf mixed forest is caused by shading from broadleaf trees. However, little is known about the mechanism underlying the interaction between them. Here, we first chose two sets of Masson pine plots approximately aged 60 years in subtropical mountainous areas in eastern China (i.e., pure coniferous forest vs. coniferous-broadleaf mixed forest). Then, we measured and compared tree height, diameter at breast height, first branch height (FBH), live crown ratio (LCR) of Masson pines between the two sets of plots, and also determined the difference in growth performance of Masson pines relative to their neighboring broadleaf trees in the mixed forest stand. Compared with plots in pine forests, Masson pines in mixed plots had lower tree height and crown breadth, higher FBH, lower LCR, and leaf area. Furthermore, the difference of mean FBH between reference trees (Masson pines) and their neighboring trees (i.e., broadleaf trees) in mixed forest plots was greater than that in pine forest plots, and the ratio of LCR between Masson pines and their neighbors (0.46) in mixed forest was significantly smaller than in pine forest (1.05), indicating that those broadleaf trees around Masson pines probably affected their growth. The mean distance between Masson pines and neighboring trees (1.59 m) in mixed forest plots was significantly shorter than in pine forest plots (2.77 m) (p < 0.01), suggesting that strong competition may occur between reference trees and their neighbors. There was a significant difference in the ratio of crown volume between reference tree Masson pine and its neighboring trees in mixed forests (p < 0.01), indicating that the ratio of biomass synthesis to consumption of pines was much lower than their nearby broadleaf trees in mixed forest. Our results have demonstrated for the first time that Masson pines’ population decline is affected by shade-tolerant broadleaf late-successional species, which can be primarily attributed to the distinctive light transmittance of dominant species nearby (pure pine vs. mixed forest). This study provides a new perspective for future studies on the mechanism of forest succession.

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Can Carbon Sequestration in Tasmanian “Wet” Eucalypt Forests Be Used to Mitigate Climate Change? Forest Succession, the Buffering Effects of Soils, and Landscape Processes Must Be Taken into Account

International Journal of Forestry Research ◽

10.1155/2020/6509659 ◽

2020 ◽

Vol 2020 ◽

pp. 1-16

Author(s):

Peter D. McIntosh ◽

James L. Hardcastle ◽

Tobias Klöffel ◽

Martin Moroni ◽

Talitha C. Santini

Keyword(s):

Climate Change ◽

Forest Fires ◽

Forest Succession ◽

Mixed Forest ◽

Mixed Forests ◽

Soil C ◽

C Stocks ◽

Mitigate Climate Change ◽

Eucalypt Forests

Small areas of the wetter parts of southeast Australia including Tasmania support high-biomass “wet” eucalypt forests, including “mixed” forests consisting of mature eucalypts up to 100 m high with a rainforest understorey. In Tasmania, mixed forests transition to lower biomass rainforests over time. In the scientific and public debate on ways to mitigate climate change, these forests have received attention for their ability to store large amounts of carbon (C), but the contribution of soil C stocks to the total C in these two ecosystems has not been systematically researched, and consequently, the potential of wet eucalypt forests to serve as long-term C sinks is uncertain. This study compared soil C stocks to 1 m depth at paired sites under rainforest and mixed forests and found that there was no detectable difference of mean total soil C between the two forest types, and on average, both contained about 200 Mg·ha−1 of C. Some C in subsoil under rainforests is 3000 years old and retains a chemical signature of pyrogenic C, detectable in NMR spectra, indicating that soil C stocks are buffered against the effects of forest succession. The mean loss of C in biomass as mixed forests transition to rainforests is estimated to be about 260 Mg·ha−1 over a c. 400-year period, so the mature mixed forest ecosystem emits about 0.65 Mg·ha−1·yr−1 of C during its transition to rainforest. For this reason and because of the risk of forest fires, setting aside large areas of wet eucalypt forests as reserves in order to increase landscape C storage is not a sound strategy for long-term climate change mitigation. Maintaining a mosaic of managed native forests, including regenerating eucalypts, mixed forests, rainforests, and reserves, is likely to be the best strategy for maintaining landscape C stocks.

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Appropriate Removal of Forest Litter is Beneficial to Pinus tabuliformis Carr. Regeneration in a Pine and Oak Mixed Forest in the Qinling Mountains, China

Forests ◽

10.3390/f10090735 ◽

2019 ◽

Vol 10 (9) ◽

pp. 735

Author(s):

Xueying Huo ◽

Dexiang Wang ◽

Deye Bing ◽

Yuanze Li ◽

Haibin Kang ◽

...

Keyword(s):

Activated Carbon ◽

Seed Germination ◽

Natural Regeneration ◽

Mixed Forest ◽

Forest Litter ◽

Pine Forest ◽

Qinling Mountains ◽

Mixed Forests ◽

Pinus Tabuliformis ◽

Plant Ash

Research Highlights: Natural regeneration is important in pine–oak mixed forests (Pinus armandii Franch., Pinus tabuliformis Carr., and Quercus aliena Bl. var. acuteserrata Maxim.ex Wenz.), but allelopathy as a limiting factor has not been studied. Our research provides insights into allelopathy in pine–oak mixed forest litter. Background and Objectives: Allelopathy among tree species occupying the same ecological niche in mixed forests may adversely affect regeneration. We studied allelopathy in pine and oak forest litter to determine the effect on regeneration, whether it is offset by adding activated carbon or plant ash, and what allelopathic substances are present. Materials and Methods: We used laboratory seed culture and field seeding to determine pine and oak litter regeneration effects on P. tabuliformis and P. armandii in the Qinling Mountains, China. In the laboratory, we irrigated seeds with three different litter concentrations. A fourth treatment incorporated activated carbon. The field study established small quadrats in mixed forest to study how removing or retaining litter and spreading plant ash affected sown seeds. High performance liquid chromatography–mass spectrometry was used to compare differences in chemical substances in extracts with and without activated carbon. Results: Litter extracts significantly affected germination rates in both species. Seedling morphological and physiological indexes showed that litter extracts negatively affected growth in both species, but activated carbon alleviated this inhibitory effect on P. armandii. Forest stand and litter did not affect P. armandii seed germination. Pinus tabuliformis germination rates were significantly higher in plots with removed litter than when litter was retained or plant ash spread, and lower in oak than pine forest. Allelopathic substances detected in pine forest were trioctyl trimellitate, amyloid β-Peptide 10–20, and triisobutyl phosphate, potentially affecting P. armandii seed germination and growth. Conclusions: Appropriate removal of litter in mixed forests can improve the natural regeneration ability of P. tabuliformis.

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Diversity and distribution of the large centipedes (Chilopoda: Scolopendromorpha) in the Phia Oac - Phia Den National Park, Vietnam

Journal of Threatened Taxa ◽

10.11609/jott.7451.13.8.19102-19107 ◽

2021 ◽

Vol 13 (8) ◽

pp. 19102-19107

Author(s):

Le Xuan Son ◽

Nguyen Thi Tu Anh ◽

Tran Thi Thanh Binh ◽

Thu Anh T. Nguyen ◽

Anh D. Nguyen

Keyword(s):

National Park ◽

Mixed Forest ◽

Pine Forest ◽

Bamboo Forest ◽

Mixed Forests ◽

Elevation Range ◽

Different Types

The scolopendromorph fauna of the Phia Oac - Phia Den National Park, northernmost Vietnam has been studied. As a result, a total of 17 species in eight genera and three families have been recorded in five different types of habitats (wood forest, bamboo forest, wood-bamboo mixed forest, pine forest, and grassland-shrubs) and from three elevation range (<1,000 m, 1,000–1,600 m, and >1,600 m). Scolopendridae is the most diverse family with nine recorded species. Of the five habitats, most species have been found in wood forests and wood-bamboo mixed forests (11 species each habitat), and at the elevation range of 1,000–1,600 m (15 species). The research also recommended that this number does not reflect the true biodiversity of this region; more intensive surveys are needed to have a better understanding of the scolopendromorph diversity in the Phia Oac - Phia Den National Park.

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Preliminary afforestation effect of the mixed forest Betula alnoides in southern Fujian China

Agricultural Reviews ◽

10.18805/ijare.a-409 ◽

2019 ◽

Author(s):

Bihua Chen ◽

Bijiang Fang ◽

Guobiao Chen ◽

Qinggen Chen ◽

Xinhua Dai ◽

...

Keyword(s):

Early Stage ◽

Mixed Forest ◽

Tree Height ◽

National Forest ◽

Beijing Area ◽

Significant Difference ◽

One Year ◽

Betula Alnoides ◽

Forest Farm ◽

Small Forest

The tissue-cultured seedlings of Betula alnoides were introduced to plant in Wanshiqing Area of Fujian Hua’an Jinshan National Forest Farm and Beijing Area of Fujian Longhai Jiulongling National Forest Farm. B.alnoides was mixed with Castanopsis hystrix with 4 patterns in Wanshiqing Area, and mixed with Cunninghamia lanceolata with three patterns in Beijing Area. After one year the sample plots were set and each tree in the plots was investigated. The results showed the effects of the mix afforestation patterns to the growth of B. alnoides were significant difference in the early stage. The optimal pattern was the pure forest of B. alnoides with the best tree height and DBH. It was possible that the pure forest crowns closed after one year and created a small forest climate. The termites, crickets, Anoplophora chinensis and Batocera lineolata were found damaging to the B. alnoide in Wanshiqing Area, but not in Beijing Area.

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Analysis The Effect of Gene and Platelet Testing Guide Dual Anti-Upgrade Therapy After PCI in Patients With ACS

10.21203/rs.3.rs-1201847/v1 ◽

2021 ◽

Author(s):

Guofeng Guo

Keyword(s):

Platelet Reactivity ◽

Light Transmittance ◽

Loss Of Function ◽

Significant Difference ◽

Cyp2c19 Gene ◽

Allele Group ◽

Risk Patients ◽

The Difference ◽

Medical University

Abstract Objective To analyze whether CYP2C19 gene and platelet testing guide ACS patients PCI benefit from postoperative dual antiplatelet escalation therapy. Methods Selecting ACS patients with 209 routine PCI surgery from January 2018 to January 2019 in Department of Cardiology, Third Affiliated Hospital of Guangzhou Medical University. Preoperative administration of aspirin 300mg and clopidogrel 600mg, and continued administration of clopidogrel 75mg/d and aspirin 100mg/d after operation. Genotype and light transmittance aggregation (LTA) was detected by gene chip 24 h after operation. According to genotype the remaining patients were divided into non loss of function (Non-LOF) alleles group Extensive-metabolisms (EMs) type, loss of function (LOF) alleles group as Intermediate metabolic (IMs) type and Poor-metabolisms (PMs) type. Define the maximum platelet aggregation rate (MPA)≥46% as hyperplatelet reactivity (HPR). The LOF group consisted of 23 patients who had both HPR and proclopidogrel and were upgraded to tigrillo for further treatment.The remaining patients without HPR who continued to be treated with clopidogrel comprised 90 patients in the LOF group without upgrade and 95 patients in the non-LOF group who continued to be treated with clopidogrel.Major adverse cardiovascular events (MACE) were recorded in the follow-up period of 1 year, and the incidence of MACE in the three groups was compared to determine whether gene and platelet detection could guide the benefit of dual anti-platelet upgrade therapy in ACS patients after PCI. Results There were 26 cases occurred during follow-up MACE, among which the incidence of unstable angina recurrence and overall MACE in the LOF allele-not-up group was the highest and significantly different compared with the Non-LOF allele group (P<0.05), there was no significant difference compared with the LOF allele-up group (0.05). while there was no significant difference between the Non-LOF allele and the LOF allele upgrading group (P>0.05). Conclusions Gene is an important factor in the difference of platelet reactivity and is associated with MACE. Upgraded treatments for high-risk patients screened for gene and platelet testing did not benefit.

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Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals

Diseases of Aquatic Organisms ◽

10.3354/dao03468 ◽

2020 ◽

Vol 139 ◽

pp. 93-102 ◽

Cited By ~ 3

Author(s):

MF Van Bressem ◽

P Duignan ◽

JA Raga ◽

K Van Waerebeek ◽

N Fraijia-Fernández ◽

...

Keyword(s):

South Africa ◽

Bone Development ◽

Bottlenose Dolphins ◽

Fatal Outcome ◽

Population Level ◽

Cape Coast ◽

Osteolytic Lesions ◽

Immune Mediated ◽

Significant Difference ◽

The Difference

Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature T. aduncus 4.6 times more likely affected than adults, while for S. plumbea, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 S. plumbea, 21 T. aduncus), suggesting potential cohort-linked immune-mediated resistance to infestation. Crassicauda spp. may play a role in the natural mortality of S. plumbea and T. aduncus, but the pathogenesis and population level impact remain unknown.

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Perbedaan Penggunaan Antikoagulan K2EDTA DAN K3EDTA Terhadap Hasil Pemeriksaan Indeks Eritrosit

Jurnal Laboratorium Khatulistiwa ◽

10.30602/jlk.v1i2.147 ◽

2018 ◽

Vol 1 (2) ◽

pp. 114

Author(s):

Wahdaniah Wahdaniah ◽

Sri Tumpuk

Keyword(s):

Screening Test ◽

Venous Blood ◽

The Body ◽

Ethylene Diamine ◽

P Value ◽

Cross Sectional ◽

Significant Difference ◽

Ethylene Diamine Tetra Acetate ◽

The Difference ◽

Index Value

Abstract: Routine blood examination is the earliest blood test or screening test to determine the diagnosis of an abnormality. Blood easily froze if it is outside the body and can be prevented by the addition of anticoagulants, one of which Ethylene Diamine Tetra Acetate (EDTA). Currently available vacuum tubes containing EDTA anticoagulants in the form of K2EDTA and K3EDTA. K3EDTA is usually a salt that has better stability than other EDTA salts because it shows a pH approaching a blood pH of about 6.4. The purpose of this research is to know the difference of erythrocyte index results include MCH, MCV and MCHC using K3EDTA anticoagulant with K2EDTA. This research is a cross sectional design. This study used venous blood samples mixed with K2EDTA anticoagulant and venous blood mixed with K3EDTA anticoagulants, each of 30 samples. Data were collected and analyzed using paired different test. Based on data analysis that has been done on MCH examination, p value <0,05 then there is a significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value. Then on the examination of MCV and MCHC obtained p value <0.05 then there is no significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value.Abstrak: Pemeriksaan darah rutin merupakan pemeriksaan darah yang paling awal atau screening test untuk mengetahui diagnosis suatu kelainan. Darah mudah membeku jika berada diluar tubuh dan bisa dicegah dengan penambahan antikoagulan, salah satunya Ethylene Diamine Tetra Acetate (EDTA). Dewasa ini telah tersedia tabung vakum yang sudah berisi antikoagulan EDTA dalam bentuk K2EDTA dan K3EDTA. K3EDTA biasanya berupa garam yang mempunyai stabilitas yang lebih baik dari garam EDTA yang lain karena menunjukkan pH yang mendekati pH darah yaitu sekitar 6,4. Tujuan dari penelitian ini adalah untuk mengetahui perbedaan hasil indeks eritrosit meliputi MCH, MCV dan MCHC menggunakan antikoagulan K3EDTA dengan K2EDTA. Penelitian ini merupakan penelitian dengan desain cross sectional. Penelitian ini menggunakan sampel darah vena yang dicampur dengan antikoagulan K2EDTA dan darah vena yang dicampur dengan antikoagulan K3EDTA, masing-masing sebanyak 30 sampel. Data dikumpulkan dan dianalisis menggunakan uji beda berpasangan. Berdasarkan analisis data yang telah dilakukan pada pemeriksaan MCH didapatkan nilai p < 0,05 maka ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit. Kemudian pada pemeriksaan MCV dan MCHC didapatkan nilai p < 0,05 maka tidak ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit.

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Pengaruh Jumlah Pencucian Beras dengan Kadar Klorin

Jurnal Laboratorium Khatulistiwa ◽

10.30602/jlk.v1i1.102 ◽

2017 ◽

Vol 1 (1) ◽

pp. 89

Author(s):

Indah Purwaningsih ◽

Supriyanto Supriyanto

Keyword(s):

Mucous Membrane ◽

Confidence Level ◽

Iodometric Titration ◽

Titration Method ◽

Anova Test ◽

Average Value ◽

Significant Difference ◽

The Difference

Abstract: Chlorine is a green halogen-shaped halogen gas at normal temperature and serves as bleach, stain remover and disinfectant. Chlorine is now widely used for bleaching rice so that less quality rice looks like quality rice. Chlorine is very toxic and causes mucous membrane irritation, highly reactive and very powerful oxidizer. The purpose of this research was to determine the difference of chlorine level in chlorinated rice washed once, twice and 3 times. The sample in this study amounted to 11 samples calculated by replication formula. Each sample was treated 3 times, ie 1 washed once, 2 washed twice and washed 3 times. The samples then examined by iodometric titration method. Based on the results of the study using ANOVA test, 11 samples obtained the average value of chlorine after washed once amount of 0.0176%, after washed twice amount of 0.0111%, and after washed 3 times amount of 0.0052% with the value significance p = 0.03 (p <0.05) at 95% confidence level which means there was a significant difference between chlorine levels in chlorinated rice washed once, twice and 3 times.Abstrak: Klorin merupakan unsur halogen berbentuk gas berwarna kuning kehijauan pada suhu normal danberfungsi sebagai pemutih, penghilang noda maupun desinfektan. Klorin sekarang banyak digunakan untuk bahan pemutih beras agar beras yang kurang berkualitas tampak seperti beras berkualitas. Klorin sangat toksik dan menyebabkan iritasi membran mukosa, sangat reaktif dan merupakan oksidator yang sangat kuat. Tujuan dari penelitian ini ialah untuk mengetahui perbedaan kadar klorin pada beras berklorin yang dicuci sebanyak 1 kali, 2 kali dan 3 kali. Sampel dalam penelitian ini berjumlah 11 sampel yang dihitung dengan rumus replikasi. Setiap sampel diberi perlakuan sebanyak 3 kali, yaitu 1 kali pencucian, 2 kali pencucian dan 3 kali pencucian. Sampel penelitian kemudian diperiksa dengan metode titrasi iodometri. Berdasarkan hasil penelitian menggunakan uji Anova secara komputerisasi terhadap 11 sampel diperoleh nilai rata-rata kadar klorin setelah 1 kali pencucian sebesar 0,0176 %, setelah 2 kali pencucian sebesar 0,0111 %, dan setelah 3 kali pencucian sebesar 0,0052 % dengan nilai signifkansi p = 0,03 (p<0,05) pada tingkat kepercayaan 95% yang artinya ada perbedaan yang bermakna antara kadar klorin pada beras berklorin yang dicuci sebanyak 1 kali, 2 kali dan 3 kali.

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P-Removal in Completely Mixed Systems

Water Science & Technology ◽

10.2166/wst.1985.0254 ◽

1985 ◽

Vol 17 (11-12) ◽

pp. 325-326 ◽

Cited By ~ 2

Author(s):

H J. G. W. Donker ◽

P. Opic ◽

H. P. de Vries

Keyword(s):

Mixed System ◽

Domestic Waste ◽

Recirculation Flow ◽

Start Up ◽

Significant Difference ◽

Aerobic Reactor ◽

The Difference ◽

Positive Effect ◽

Mixed Systems ◽

P Removal

Ca. 60 % of the Dutch activated sludge plants consist of completely mixed systems, experiments have been carried out in completely mixed pilot plants to study the biological P-removal. The research was carried out in two pilot plants. The pilot plants consisted of: anaerobic reactor, anoxic reactor, aerobic reactor and a clarifier. All the reactors were completely mixed. Both plants were fed with settled domestic waste water at a sludge loading of 400 and 250 g COD/kg sludge.day respectively. The results are given below:sludge loading (g COD/kg sludge.day)400400250ratio Anaerobic : Anoxic : Aerobic1: 1:2,71:1:4,11:1:2,7P-removal (%)802875N-removal (%)505065COD-removal (%)858585 It has been shown that there is no significant difference between the results at the two different sludge loadings. Remarkable is the difference between the ratio 1:1:2,7 in combination with the internal recirculation flow anoxic-anaerobic of 160 % and the ratio 1:1:4,1 with a recirculation flow of 30 %. During the start-up at a sludge loading of 250 g COD/kg sludge.day and an internal recirculation flow of 30 %, bulking sludge developed almost immediately. The Premoval was completely disturbed. Increasing the internal recirculation flow to 160% had a positive effect on settling properties and P-removal. This investigation has pointed out that a completely mixed system is suitable for biological P-removal, without negatively affecting the nitrification. Important factors in the process are the ratio anaerobic:anoxic:aerobic and the recirculation flows.

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Effect of Levetiracetam on Cognitive Function and Clonic Seizure Frequency in Children with Epilepsy

Current Molecular Medicine ◽

10.2174/1566524019666190729113321 ◽

2019 ◽

Vol 19 (9) ◽

pp. 699-703

Author(s):

Shihao Zhou ◽

Qiong Zhan ◽

Xiaomei Wu

Keyword(s):

Cognitive Function ◽

Effective Rate ◽

Clonic Seizure ◽

Conventional Group ◽

Significant Difference ◽

Random Number Table ◽

Clonic Seizures ◽

The Difference ◽

Experimental Group ◽

Executive Ability

Background: This study aimed to explore the clinical effect of levetiracetam in the treatment of children with epilepsy. Methods: 136 children with epilepsy were selected from January 2017 to December 2017. According to the random number table method, they were divided into the experimental group and the conventional group, with 68 cases in each group. The conventional group was treated with valproate, while the experimental group was treated with levetiracetam. The effective rate, the cognitive function and the frequency of clonic seizures in the two groups were compared. Results: There was no significant difference in the total effective rate between the two groups (P>0.05). There was no significant difference in attention, executive ability, abstract and orientation scores between the two groups before treatment (P>0.05). After treatment, the focus of attention (106.54±6.56), executive ability (105.76±6.77), abstract and directional score (106.65±6.57) were significantly higher than that of the conventional group. The difference in the two groups was statistically significant (P<0.05). After 3 months of treatment, the frequency of myoclonic seizures (9.22±0.95) and the frequency of tonic-clonic seizures (11.68±1.36) were found to be significantly lower than those of the conventional group, and the difference between the two groups was statistically significant (P<0.05). Conclusion: Levetiracetam is effective in the treatment of children with epilepsy. It can effectively improve the cognitive function of the patients, reduce the frequency of myoclonic seizures and tonic-clonic seizures, and has a high promotion value.

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