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In situ posture of anterior body of Metagonimus yokogawai in experimentally infected dog (개의 실험적 요꼬가와흡충증에서 충체의 자세)

  • 장영기;강신영
    • Parasites, Hosts and Diseases
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    • v.23 no.2
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    • pp.203-213
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    • 1985
  • The in situ posture of anterior body of Metagonimus yokogawai was observed in experimental metagonimiasis of dog. The metacercariae were collected from naturally infected sweetfish by peptic digestion; a total of 8 dogs was orally infected with 10,000 metacercariae respectively. Two dogs were killed on 3 days, 9 days, 4 weeks and 10 weeks after the infection. The postures of worms in histological section of small intestine and of whole worms collected from the fixed intestinal mucosa were examined by light and scanning electron microscope. The results were summarized as follows: 1. The recovery rates of worms were 42.6% on 3 days, 55.0% on 9 days, 33.2% on 4 weeks and 9. 8% on 10 weeks after the infection respectively. 2. In histological sections of small intestine, most of worms were found at intervillous spaces as ovoid sections of posterior body. However, many worms, especially in 3 day-old worms, revealed protruded anterior body in glandular lumens of crypt. Some sections of anterior body were bifurcated or sacculated. 3. The worms collected from fixed intestinal mucosa under dissecting microscope exhibited a variety of postures. Many worms showed flat shapes with a concavity or curvatures. However, in many worms, the anterior body made a single or multiple protrusions. 4. By SEM observation of protruded anterior body, a longitudinal groove was found. 5. The frequency of worms with protruded anterior body decreased in 9 days, 4 weeks and 10 weeks than in 3 day-old worms. The above findings indicated that the anterior body of juvenile and adult M. yokogawai protruded to lumens of glandular crypt by folding their lateral portions to make a reversible tubelike structure. Frequent multiple protrusions were considered to be made to adapt the microniche of glandular crypts of dog intestine.

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Phytochemical compounds and quality characteristics of spray-dried powders with the blanching condition and selected forming agents from pressed extracts of Ligularia fischeri leaves (블랜칭 처리 및 부형제 종류에 따른 곰취 착즙액 분무건조 분말의 phytochemical 성분 및 품질특성)

  • Kim, Jae-Won;Park, In-Kyung;Youn, Kwang-Sup
    • Food Science and Preservation
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    • v.20 no.5
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    • pp.659-667
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    • 2013
  • This study was performed to determine the effects of the blanching condition (immersion ratio 1:15 (w/v) for 3 min at $95^{\circ}C$, and solution containing 1% sodium chloride) and selected forming agents (dextrin DE=10, dextrin DE=20, ${\beta}$-cyclodextrin; each forming agents added 5%) on the phytochemical compounds and quality characteristics of Ligularia fischeri leaves. The moisture was not affected by the forming agent. The color of a, b and chroma values were low in the blanching treatment groups and were significantly lowest with ${\beta}$-cyclodextrin (CD). The polyphenol and flavonoid contents in the blanching treatment groups were higher than those in the non-blanching-treatment group. The ascorbic acid content was higher in the non-blanching-treatment group and was significantly highest in the group treated with dextrin (DE=10) whereas the blanching treatment groups showed lower dehydroascorbic acid content than the non-blanching-treatment group. The water absorption was higher in the non-blanching-treatment group and was significantly highest in the group treated with CD. The water solubility in the blanching treatment groups treated with dextrin (DE=20) and CD was higher than that in the blanching treatment group treated with DE=10. The total chlorophyll and chlorophyll a and b contents were high in the blanching treatment group treated with CD, and for the total carotenoid contents, the same tendency as that seen with the chlorophyll content was observed. With regard to the particle diameter, those in the blanching treatment groups were lower than that in the non-blanching-treatment group and was significantly lowest in the blanching treatment groups treated with DE=20 and CD. The result of SEM observation showed that the spray-dried powders in blanching treatment groups treated with the DE=20 and CD forming agents had uniform particle distribution.

Microsporogenesis of Hibiscus syriacus L and Its Sporoderm Differentiation (무궁화의 화분형성 및 화분벽의 분화발달)

  • 김인선
    • Journal of Plant Biology
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    • v.38 no.1
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    • pp.95-105
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    • 1995
  • Complete microsporogenesis of Hibiscus syriacus L. were carried out employing LM, TEM, and SEM to investigate the pollen ontogeny that undergoes considerable structural differentiation. The process first began with several cell diYisions in the anther primordium that produces 3 different tissues of epidennal, archesporial, and connective tissues. Only archesporial tissue involved further differentiation into the tapetum and formation of reproductive cells, pollen mother cells (PMC). The tapetum and PMC were closely associated with each other structurally and metabolically by exhibiting numerous plasmodesmata, mitochondria, and many small vacuoles in their dense cytoplasm. A callosic wall began to surround the PMC while meiosis took place in the PMC to produce 4 microspores. When thick callose encircled each microspore as a frame, the sporodenn development initiated from the plasma membrane of a pollen grain in a tetrad. The first fonned sporoderm layer was bacules and tectum of sexine that originated from the plasma membrane. After the dissolution of a callose, further development Qf sporoderm continued in the order of nexine 1, nexine 2, and intine layer. The nexine layer was thicker (ca. $2-3.5\;\mu\textrm{m}$) than the intine layer whose thickness was about $0.9-1.5\;\mu\textrm{m}$. Upon completion of the sporoderm development, that is after intine formation, spines and apertures of pollen surface ornamentation initiated from the tectum. Spines were dimorphic, about $4-9\;\mu\textrm{m}\;an;15-20\;\mu\textrm{m}$ in length, and no basal cushion was detected. The mature pollen grains ranged $100-200\;\mu\textrm{m}$ in diameter, but their average was about $170\;\mu\textrm{m}$. About 120 spines were observed over the spheroidal pollen surface. Apertures were simple punctures of $2-3\;\mu\textrm{m}$ in diameter and about 50 apertures were arranged somewhat helically over the surface. Comparing such features of form and size of the pollen, sporodenn sculpture and structure, and aperture and spine conditions with known evolutionary trends in the genus Hibiscus, Hibiscus syriacus seemed to possess many advanced features in the sporodenn differentiation.iation.

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Antiemetic Effect of Dexamethasone in Dogs Sedated with Xylazine (Xylazine hydrochloride로 진정시킨 개에 대한 Dexamethasone의 항구토 효과)

  • Yang Jung-hoon;Kang Han-sem;Bae Jae-sung;Song Chang-hyun;Kim Jung-eun;Jin Hee-kyung;Jang Kwang-ho
    • Journal of Veterinary Clinics
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    • v.22 no.2
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    • pp.94-99
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    • 2005
  • This prospective study aimed to assess the efficacy of dexamethasone to prevent xylazine induced emesis in dogs. The antiemetic effect of graded, single high-dose intravenous dexamethasone against xylazine hydrochloride was studied. Clinically healthy mixed breed dogs that weighed $ 4.64\pm1.25kg$ were used in this study. Food and water were given 3 hours before the experiment. Venous blood specimens were collected from all experimental animals for hema-tological and blood chemical test pre- and post-experiment. Twenty-eight experimental animals were randomly divided into 4 groups; the group treated with 0.2ml/kg of normal saline (Control group), the groups treated with 1mg/kg (D1 group), 2mg/kg (D2 group) and 4 mg/kg of dexamethasone (D4 group). Three doses of the dexamethasone or normal saline was administered intravenousely to each group and after 5 minutes, xylazine (2.2 mg/kg) was administered intramuscularly. The time until onset of the first emetic episode and rate of emesis were investigated. At the same time, the extent of sedation was scored subjectively 5, 15, 30 and 60 minutes after injection of xylazine hydrochloride using Visual Sedation Score. The time until onset of the first emetic episode was $203.25\pm11.35$ sec in Control group, $187.33\pm48.0l$ sec in D1 group and 218.33± 13.58 sec in D2 group. The rate of xylazine induced emesis were $57\%$ in Control group and $43\%$ in D1 and D2 group respectively. On the other hand, any emetic episodes were not observed in 04 group. At extent of sedation score, all experimental animals especially including the animals in D1 group were highly sedated at 15 minutes after administration of xylazine hydrochloride. Hematological and blood chemical values showed normal ranges pre- and post-experiment. We concluded that prior treatment with 4 mg/kg of dexamethasone hardly caused xylazine-induced emesis without disturbing the sedative effect of xylazine in dogs.

Study on Affecting Variables Appearing through Chemical Pretreatments of Poplar Wood (Populus euramericana) to Enzymatic Hydrolysis (이태리 포플러의 화학적 전처리 공정을 통한 효소가수분해 영향 인자 분석)

  • Koo, Bon-Wook;Park, Nahyun;Yeo, Hwanmyeong;Kim, Hoon;Choi, In-Gyu
    • Journal of the Korean Wood Science and Technology
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    • v.37 no.3
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    • pp.255-264
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    • 2009
  • To evaluate the effects of chemical pretreatments of lignocellulosic biomass on enzymatic hydrolysis process, Populus euramericana was pretreated for 1 hr with 1% sulfuric acid ($H_2SO_4$) at $150^{\circ}C$ and 1% sodium hydroxide (NaOH) at $160^{\circ}C$, respectively. Before the enzymatic hydrolysis, each pretreated sample was subjected to drying process and thus finally divided into four subgroups; dried or non-dried acid pretreated samples and dried or non-dried alkali pretreated samples and chemical and physical properties of them were analyzed. Biomass degradation by acid pretreatment was determined to 6% higher compared to alkali pretreatment. By the action of acid ca. 24.5% of biomass was dissolved into solution, while alkali degraded ca. 18.6% of biomass. However, reverse results were observed in delignification rates, in which alkali pretreatment released 2% more lignin fragment from biomass to the solution than acid pretreatment. Unexpectedly, samples after both pretreatments were determined to somewhat higher crystallinity than untreated samples. This result may be explained by selective disrupture of amorphous region in cellulose during pretreatments, thus the cellulose crystallinity seems to be accumulated in the pretreated samples. SEM images revealed that pretreated samples showed relative rough and partly cracked surfaces due to the decomposition of components, but the image of acid pretreated samples which were dried was similar to that of the control. In pore size distribution, dried acid pretreated samples were similar to the control, while that in alkali pretreated samples was gradually increased as pore diameter increased. The pore volume which increased by acid pretreatment rapidly decreased by drying process. Alkali pretreatment was much more effective on enzymatic digestibility than acid pretreatment. The sample after alkali pretreatment was enzymatically hydrolyzed up to 45.8%, while only 26.9% of acid pretreated sample was digested at the same condition. The high digestibility of the sample was also influenced to the yields of monomeric sugars during enzymatic hydrolysis. In addition, drying process of pretreated samples affected detrimentally not only to digestibility but also to the yields of monomeric sugars.

The Difference of the Cleaning and Wettability-maintaining Efficacy of Lens Care Solution to RGP Lens (관리 용품에 따른 RGP 렌즈의 세척효과 및 습윤성 차이)

  • Kim, Myoung-Hea;Park, Mi-Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.1
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    • pp.27-34
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    • 2006
  • We investigated the question whether the efficacy of cleaning tear components on RGP lens and preserving the superior wettability of RGP lens depended on the different type of contact lens care system - RGP lens care solution, SCL care solution, combined solution both for SCL and RGP lens or saline solution. The removal efficacy of the deposited protein was examined by Lowry protein assay and Scanning Electro Microscope(SEM) and residual lipid concentration on RGP lens was determined by High Pressure Liquid Chromatology(HPLC). Wettability was assessed with an equilibrium water-in-air contact angle method. When cared by RGP lens solution, it was demonstrated that 62 percent out of the adhered protein on RGP lens were removed and the removal efficacy of RGP lens solution was not only 4 times than saline solution and the alternative but also higher twice than SCL solution. Contrarily, the SCL solution had the most excellent removal efficacy of the adhered protein on SCL. These results suggest that the cleaning efficacy is thought to be affected by the other factors like the viscosity of care solutions, which mutual contact between RGP lens and care solutions is on the increase due to the viscosity enhancer in RGP lens care solution. RGP lens solution had the greatest removing efficacy to cholesterol and the residual cholesterol concentration was decreased to 50%. It is significant for RGP lens to preserve the superior wettability which means the predictive value for comfortable wearing and it showed that the RGP lens solution offered the most excellent efficacy to maintain the surface wettability. Combined solution both for SCL and RGP lens had weak efficacy of cleaning and maintaining wettability for RGP lens compared to RGP lens care solution.

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THE CHANGE OF THE CONFIGURATION OF HYDROXYAPATITE CRYSTALS IN ENAMEL BY CHANGES OF PH AND DEGREE OF SATURATION OF LACTIC ACID BUFFER SOLUTION (유산 완충용액의 pH 및 포화도 변화에 따른 법랑질 내 수산화인회석 결정 형태의 변화)

  • Chon, Young-Eui;Jung, Il-Young;Roh, Bung-Duk;Lee, Chan-Young
    • Restorative Dentistry and Endodontics
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    • v.32 no.6
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    • pp.498-513
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    • 2007
  • Since it was reported that incipient enamel caries can be recovered, previous studies have quantitatively evaluated that enamel artificial caries have been, remineralized with fluoride showing simultaneously the increase of width of surface layer and the decrease of width of the body of legion. There is, however, little report which showed that remineralization could occur without fluoride. In addition, the observations on the change of hydroxyapatite crystals also have been scarcely seen. In this study, enamel caries in intact premolars or molars was induced by using lactic acidulated buffering solutions over 2 days. Then decalcified specimens were remineralized by seven groups of solutions using different degree of saturation(0.212, 0.239, 0.301, 0.355) and different pH(5.0, 5.5, 6.0) over 10 days. A qualitative comparison to changes of hydroxyapatite crystals after fracturing teeth was made under SEM(scanning electron microscopy) and AFM(atomic force microscopy). The results were as follows: 1. The size of hydroxyapatite crystals in demineralized area was smaller than the normal ones. While the space among crystals was expanded, it was observed that crystals are arranged irregularly. 2. In remineralized enamel area, the enlarged crystals with various shape were observed when the crystals were fused and new small crystals in intercrystalline spaces were deposited. 3. Group 3 and 4 with higher degree of saturation at same pH showed the formation of large clusters by aggregation of small crystals from the surface layer to the lesion body than group 1 and 2 with relatively low degree of saturation at same pH did. Especially group 4 showed complete remineralization to the body of lesions. Group 5 and 6 with lower pH at similar degree of saturation showed remineralization to the body of lesions while group 7 didn't show it. Unlike in Group 3 and 4, Group 5 and 6 showed that each particle was densely distributed with clear appearance rather than crystals form clusters together.

Yellowish Friable Embryogenic Callus (YFEC) Production and Plant Regeneration from Immature Embryo Cultures of Domestic Maize Cultivars and Genotypes (Zea may L.) (국내 옥수수 품종 및 계통의 미숙배 배양으로부터 Yellowish Friable Embryogenic 캘러스 (YFEC) 생산과 식물체 재생)

  • Cho Mi-Ae;Park Yun-Ok;Kim Jin-Suck;Park Ki-Jin;Min Hwang-Ki;Liu Jang-Ryol;Choi Pil-Son
    • Journal of Plant Biotechnology
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    • v.32 no.2
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    • pp.117-121
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    • 2005
  • Immature embryos of 3 cultivars (Du Me Chal, Mi Baek Chal, Heug Jeom Chal) and 5 genotypes (HW1, KL103, HW3, HW4, KW7) were cultured on medium containing MS salts, Eriksson's vitamins, 1 mg/L 2,4-dichlorophenoxyacetic acid, 25 mM proline, 100 mg/L casamino acid, 3 mM MES, 1.7 mg/L $AgNO_3$ and 20 g/L sucrose (SIM). Frequency of somatic embryo formation on explant of immature embryos showed in HW1 (45.20%), KL103 (5.75%), HW3 (37.20%), HW4 (30.10%), KW70 (55.20%), Mi Baek Chal (18.74%), Heug Jeom Chal (22.41%), Du Me Chal (36.72%) and Hi II type (<10%), respectively. Yellowish friable embryogenic callus (YFEC) such as type II callus of Hi II genotype only produced from the HW3 and Heug Jeom Chal, whereas other cultivars and genotypes were directly formed somatic embryos with late-embryonic stages or expanded yellowish compact somatic embryo with morphological abnormality. The yellowish friable embryogenic callus (YFEC) could be proliferated on the same medium, which were maintained embryogenic capacity for 6 months over. Upon transfer to first regeneration and second regeneration medium, somatic embryos converted to plantlets at a frequency of approximately 100%. However, the expanded somatic embryos with abnormal morphology were slowly proliferated when subcultured on the same medium, and some of them were degenerated or converted to plantlets at a frequency of approximately 25%. Accordingly, The Heug Jeom Chal and HW3 genotype will be further used for development of high frequency transformation system in domestic maize germplasm.

PHYSICAL PROPERTIES AND SURFACE TOPOGRAPHY OF ORTHODONTIC STAINLESS STEEL WIRES : COMPARING A NEW KOREAN PRODUCT WITH OTHERS FROM FOREIGN COMPANIES (여러 스테인레스 스틸 호선의 물성 및 표면의 비교)

  • Lee, Sung-Ho;Kim, Tae-Woo;Chang, Young-Il
    • The korean journal of orthodontics
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    • v.31 no.1 s.84
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    • pp.149-157
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    • 2001
  • The purpose of this study was to investigate the property of a new Korean stainless steel wire(Jinsung Ind.) comparing with other foreign Products. Five types of stainless steel wires (Standard, Resilient, HI-T of Unitek, Stainless steel of Ormco and Jinsung Ind.) in 0.016x0.022 and 0.019x0.02 were tested to observe for Composition analysis, size difference, tensile properties, flexure bending property, tortion property, surface hardness and surface topography by means of SEM. The findings suggest that: 1. In maximum tensile strength of tensile properties, Unitek Hi-T showed the greatest value, followed by Unitek Resilient, Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Unitek Hi-T showed highest value, followed by Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Resilient, Unitek Standard in 0.019x 0.025. 2. In elongation rate, Unitek Standard showed the greatest value, fellowed by Ormco Stainless Steel, Unitek Hi-T, Unitek Resilient, Jinsung Stainless Steel in 0.016x0.022, and Unitek Hi-T showed the highest value, followed by Unitek Standard, Ormco Stainless Steel, Jinsung Stainless Steel, Unitek Resilient in 0.019x0.025. 3. In modulus of elasticity, Jinsung Stainless Steel showed the greatest value, followed by Unitek Hi-T, Unitek Resilient, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Unitek Resilient showed the highest value followed by Jinsung Stainless Steel, Ormco Stainless Steel, Unitek Hi-T, Unitek Standard in 0.019x0.025. 4. In bending fatigue test, Jinsung Stainless Steel showed the greatest fracture resistance, followed by Unitek Hi-T, Unitek Standard, Unitek Resilient, Ormco Stainless Steel in 0.016x0.022, and Unitek Hi-T showed the greatest fracture resistance followed by Jinsung Stainless Steel, Unitek Resilient, Unitek Standard, Ormco Stainless Steel in 0.019x0.025. 5. In twist test, Unitek Resilient showed the greatest fracture resistance, followed by Jinsung Stainless Steel, Unitek Hi-7, Ormco Stainless Steel, Unitek Standard in 0.016x0.022, and Jinsung showed the greatest fracture resistance, followed by Unitek Resilient, Unitek Standard, Ormco Stainless Steel, Unitek Hi-T. 6. In surface topography, every products showed indentation and pitting. Jinsung stainless steel wire showed long thin indentation and relatively smooth surface. Unitek wires showed indentation and pitting and Ormco wire showed a lot of irregular pittings.

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APPLICATION OF ACIDIC PRIMER FOR ORTHODONTIC ADHESIVE SYSTEM (Acidic primer를 이용한 교정용 브라켓 접착의 전단결합강도)

  • Kim, Jin-Hee;Jin, Hun-Hee;Oh, Jang-Kyun
    • The korean journal of orthodontics
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    • v.31 no.1 s.84
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    • pp.137-147
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    • 2001
  • Acidic primer is the bonding agent which combines the conditioning and priming agent into the single solution and was originally developed for the dentin bonding system. It is less harmful to the tooth structure and more convenient to manipulate than the traditional etching procedure. The Purpose of this study is to evaluate the shear bond strength of various bonding materials when the enamel is treated with acidic primer for the bracket bonding procedure. Fifty recently extracted human premolars were randomly separated into five groups -Group I using Clearfil Liner Bond 2 adhesive system to the enamel treated with acidic primer, Group II using Transbond XT adhesive system to the enamel treated with acidic primer, Group III using panavia 21 adhesive system to the enamel treated with acidic primer, Group IV using Fuji-Ortho LC adhesive system to the enamel treated with acidic primer, Group V using Transbond XT adhesive system to the enamel treated with 37$\%$ phosphoric acid. The shear bond strength was measured with Instron universal testing machine after storing in $37^{\circ}C$ water bath for 48 hours. After debonding, the teeth and brackets were examined under scanning electron microscope (SEM) and assessed with the adhesive remnant index (ARI). The results were as follows : 1. There were no significant differences in shear bond strength between group III ($8.69{\pm}2.72MPa$), group IV (9.7 ± 3.16 MPa), and group V ($10.48{\pm}2.60MPa$) (p>0.05). 2. The shear bond strength of group III and group IV was significantly higher than that of group I ($1.09{\pm}0.53MPa$), and Group II ($2.70{\pm}1.46MPa$) (p<0.05). 3. The ARI of group IV ($2.1{\pm}1.1$) and group V ($2.9{\pm}0.3$) was significantly higher than that of group I ($0.2{\pm}0.4$), group II ($0.3{\pm}0.9$) and group III ($0.2{\pm}0.4$) (p<0.05). 4. There were no significant difference between the ARI of group IV and group V (p>0.05). This result suggests that the combination of acidic primer and some bonding adhesive can provide sufficient shear bond strength for clinical orthodontics.

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