• 제목/요약/키워드: needles

검색결과 689건 처리시간 0.024초

Physical, chemical, mechanical, and micromorphological characterization of dental needles

  • de Oliveira Monteiro, Marco Antonio;Antunes, Alberto Nogueira da Gama;Basting, Roberta Tarkany
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제21권2호
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    • pp.139-153
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    • 2021
  • Background: In anesthetic techniques, touching bones can cause needle bending. Theoretically, a needle should support such deflection without fracturing. However, it is possible that a needle may fracture depending on the quality and type of needle used. This study evaluated the physical, chemical, and micromorphological characteristics of long and short dental anesthetic needles, as well as the mechanical properties of flexural load and bending resistance when needles are subjected to different bending angles. Methods: Long and short needles (30G, Jets, Misawa, Selekto, Terumo, Unoject and 27G, Dencojet, Injex, Jets, Misawa, Procare, Setoject XL, Terumo) were evaluated. Scanning electron microscopy was used to evaluate the needle bevels and energy-dispersive X-ray spectroscopy was used for the chemical analysis of needle compositions. Flexural loading and bending strength assessments were performed using a universal testing machine by bending the needles (n = 5) to angles of 30°, 60°, or 90°, or until fracture occurred. Results: The Injex 27G, Jets 27G, and Septoject XL 27G needles were all less than 30 mm in length. There were small percentage variations in the chemical compositions of the needles. Superior smoothness was observed for the Unoject 30G needle, which exhibited the highest fracture resistance at 60°. The Jets 30G needle exhibited greater resistance to fractures at 90°. The Procare 27G needle exhibited the highest load resistance to bending, followed by the Septoject XL 27G needle, and both needles were tied for the lowest fracture resistance. No needle fractured when bent to 30° or at less than three bends to 60° or 90°. Conclusions: Greater needle resistance to bending increases the probability of early fracturing. Thinner and shorter needles are more resistant than longer and thicker needles. Performing a single bend does not result in any significant risk of fracture or obliterate the lumen, allowing for the continued passage of anesthetic liquid.

소나무잎에 침착된 PAHs 특성 (Characteristics of PAHs Absorbed on Pine Needles)

  • 천만영
    • Environmental Analysis Health and Toxicology
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    • 제23권3호
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    • pp.213-220
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    • 2008
  • The characteristics of PAHs accumulated on pine needles which were used as passive samplers of atmospheric POPs were studied. Atmospheric PAHs were accumulated on pine needles. The absorbed rate of PAHs was higher in gaseous state than in particulate and is not constant. The accumulation rate did not change too much among different classes of pine trees. Therefore young pine needles is better as a passive sampler of atmospheric PAHs for short monitoring period.

소나무 종별 대기 중 PCBs의 침착특성 (Deposition Characteristics of Atmospheric PCBs by Type of Leaves in Pine Needles)

  • 신은상;여현구;조기철;천만영
    • 한국환경보건학회지
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    • 제32권1호
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    • pp.46-52
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    • 2006
  • Results for the concentrations of total polychlorinated biphenyls (total PCBs) and the PCB profile with different types of leaves from four coniferous trees (pine needles) at the same sampling site are presented. Concentrations of total PCBs detected in pine needles were very similar among them regardless of their different types of leaves, which means a possibility for bio-monitoring regional contamination of PCBs. Correlation coefficients(r) of PCB congeners between pine needles were very significant (r>0.97, p<0.001), which showed that PCB congener's patterns of each pine needle were similar. Profiles of PCBs detected in pine needles showed correlation with gaseous phase PCBs in air, otherwise not with particle phase PCBs in air. Therefore, it was estimated that dry gaseous deposition was a principal pathway of PCBs accumulation in pine needles. In addition, although we analyse a different types of leaves in pine needles at the same region, they can be used to identify regional contamination patterns of PCBs for larger regions.

침구의학에서 플라시보 대조군과 플라시보 효과 (Placebo Control and Placebo Effect in Acupuncture Medicine)

  • 채윤병;엔크 폴
    • Korean Journal of Acupuncture
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    • 제35권2호
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    • pp.47-55
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    • 2018
  • Objectives: Clinical improvements can be observed following placebo administrations in clinical trials. Randomized controlled trials have been conducted to disentangle the specific effects of therapeutic interventions over the past decade. In acupuncture trials, non-penetrating placebo needles offer the opportunity to determine the specific effects of needling. Methods: The present review provides an overview of the concept of the placebo effect and the characteristics of the placebo needles. Results: Placebo control can contribute to minimize for bias and the contextual and psychological components of therapeutic interventions. Placebo control should meet two criteria: blinding efficacy (indistinguishable from active treatment) and physiological inertness. In the case of acupuncture, however, it is difficult to meet both criteria simultaneously. The dilemma of placebo needles suggests that placebo needles do not constitute proper control in acupuncture research. Considering the characteristics of placebo needles, patients are more likely to perceive placebo needles as active treatment in acupuncture trials compared to placebo pills in pharmaceutical trials. Placebo response might be observed more frequently to placebo needles than to placebo pills. When acupuncture treatments are utilized in clinical use, placebo effects can be enhanced by exploiting patients' expectations in the contextual or environmental cues that surround medical intervention. Conclusions: We have to consider these unique characteristics of placebo needles in order to avoid drawing premature conclusions that acupuncture itself is just a placebo.

소나무잎에 침착된 PCBs의 샘플링 오차에 관한 연구 (A Study on The Sampling Error of PCBs Deposited on Pine Needles)

  • 천만영;김태욱
    • 한국환경농학회지
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    • 제17권2호
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    • pp.117-121
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    • 1998
  • 대기중에 PCBs의 바이오 모니터용으로 널리 이용되고 있는 소나무잎을 채취할 때 발생하는 오차를 줄이기 위한 방법에 관하여 연구한 결과 다음과 같은 결론을 얻었다. 1. 새잎에서부터 3년생 잎까지 소나무잎에 농축된 ${\sum}$PCBs의 농도는 거의 일정한 율로 증가하는 바소나무잎은 대기중 PCBs의 장기간에 걸친 바이오 모니터링용으로 이용할 수 있음을 알았다. 반면,이러한 특성은 어린잎과 오래된 잎을 혼합하여 분석하거나 서로 다른 지역 간의 오염도를 비교할 때 연도가 서로 다른 잎들 중의 농도를 비교해서는 아니된다는 것을 말해준다. 2. 서로 수령이 다른 몇 그루의 나무에서 채취한 잎중 ${\sum}$PCBs의 차이는 거의 없었다. 3. 높은 나무 꼭데기에서 자라는 잎에 침착된 ${\sum}$PCBs 농도가 지상 가까이에서 자라는 나뭇잎에서 보다 낮은 농도를 보였다. 4. 다른 나뭇가지나 숲으로 가려져 있어 통풍이 원활하지 못하는 곳에서 자라는 잎은 통풍이 잘 되는 곳에서 자란 잎에 비하여 침착된 ${\sum}$PCBs의 농도거 상당히 낮은 값을 보였다.

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Analysis of a Targeted Intervention Programme on the Risk Behaviours of Injecting Drug Users in India: Evidence From the National Integrated Biological and Behavioural Surveillance Survey

  • Sahu, Damodar;Ranjan, Varsha;Chandra, Nalini;Nair, Saritha;Kumar, Anil;Arumugam, Elangovan;Rao, Mendu Vishnu Vardhana
    • Journal of Preventive Medicine and Public Health
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    • 제55권4호
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    • pp.407-413
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    • 2022
  • Objectives: This study provides insights on the impact of a targeted intervention (TI) programme on behaviour change among injecting drug users (IDUs) in India. Methods: This paper examined the data from the Integrated Biological and Behavioural Surveillance 2014-2015 for IDUs in India. Logistic regression was performed to understand the factors (TI programme services) that affected injecting risk behaviours by adjusting for covariates. Propensity score matching was conducted to understand the impact of the TI programme on using new needles/syringes and sharing needles/syringes in the most recent injecting episode by accounting for the covariates that predicted receiving the intervention. Results: Participants who received new needles and syringes from peer educators or outreach workers were 1.3 times (adjusted odds ratio, 1.29; 95% confidence interval [CI], 1.09 to 1.53) more likely to use new needles/syringes during most recent injecting episode than participants who did not receive needles/syringes. The matched-samples estimate (i.e., average treatment effect on treated) of using new needles in the most recent injecting episode showed a 2.8% (95% CI, 0.0 to 5.6) increase in the use of new needles and a 6.5% (95% CI, -9.7 to -3.3) decrease in needle sharing in the most recent injecting episode in participants who received new needles/syringes. There was a 2.2% (95% CI, -3.8 to -0.6) decrease in needle sharing in the most recent injecting episode among participants who were referred to other services (integrated counselling and testing centre, detox centres, etc.). Conclusions: The TI programme proved to be effective for behaviour change among IDUs, as substantiated by the use of new needles/syringes and sharing of needles/syringes.

미녹시딜을 내포한 용융형 고분자 마이크로 니들의 길이에 따른 특성 및 발모 효능 관찰 (Characteristics and Hair Growth Efficacy of Water Dissolving Micro-needles Containing Minoxidil Regarding Length of Micro-needles)

  • 한미리;김은영;정용현;김명석;박정환
    • 폴리머
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    • 제37권3호
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    • pp.393-398
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    • 2013
  • 본 실험에선 미녹시딜을 함유한 수용성 고분자 젤로부터 solvent casting 방법으로 250과 $750{\mu}m$ 두 가지 길이의 미녹시딜이 함유된 용융형 고분자 마이크로 니들(micro-needle)을 제작하였다. 제작된 미녹시딜을 함유한 용융형 고분자 마이크로 니들은 기계적 강도가 입증된 고분자 니들과 동일한 형태 및 기계적 강도를 나타냈으며, 성공적으로 피부를 투과함을 확인하였다. 제조된 고분자 마이크로 니들의 경우 피부 적용 후 최소 30분 이상은 부착되어야 전체 니들의 50% (v/v) 이상이 피부 내로 용융되었으며, 니들 적용부위에서 서서히 약물의 방출 및 확산을 확인할 수 있었다. 또한 C57BL/6 동물 모델을 통해 미녹시딜이 함유된 250, $750{\mu}m$ 길이의 고분자 마이크로 니들이 무처리군 혹은 미녹시딜 처리군에 비해 발모에 긍정적인 영향을 나타냄을 확인할 수 있었다.

솔잎 추출물의 염색성과 기능성 (제1보) -솔잎 추출물의 특성과 셀룰로오스섬유에 대한 염색성- (Dyeability and Functionality of Pine Needles Extract (part I) -Characteristics of Pine Needles Extract and Dyeing Properties of Cellulose Fiber-)

  • 우효정;이정순
    • 한국의류학회지
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    • 제35권2호
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    • pp.218-229
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    • 2011
  • Dyeing properties of cotton and ramie fabrics with pine needles colorants were studied by investigating the analysis of pine needles colorants, the effect of dyeing conditions (such as dye concentration, dyeing temperatures and times on dye uptakes), effect of mordants, and color change. The various colorfastness of dyed fabrics were evaluated for practical use; in addition, the antimicrobial ability, ultraviolet-cut ability, and deodorant ability were estimated. In the UV-Visible spectrum, the wavelength of the maximum absorption for pine needles extract was 285nm, and pine needles colorants produced a yellow color. From FT-IR and GC-MS results, it was assumed that chromophoric substance from pine needles extracts were mixed with flavonol tannin and flavanol tannin. An increased dyeing concentration resulted in a larger dye uptake and a Freundlich absorption isotherm was obtained. A larger dye uptake occurred as the dyeing time and temperature increased. Post-mordanting was more effective than pre-mordanting and the dye uptake of fabrics improved by mordanting. The colorfastness of dyed fabrics showed a low rating; however, colorfastness to washing and dry cleaning of cotton fabrics mordanted with N.Cu, and friction fastness of ramie fabric mordanted with Cu improved. The dyed fabrics showed very good antimicrobial abilities of 99.9%. In addition, the ultraviolet-cut ability and deodorant ability improved in fabrics dyed with pine needles extracts.

솔잎 추출물의 성분 분석 및 염색물의 건강안전 기능성 평가 (Components of Pine Needles Extract and Functionality of the Dyed Fabrics)

  • 전미선;박명자
    • 복식문화연구
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    • 제18권2호
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    • pp.371-381
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    • 2010
  • The pine needles can be used for four seasons in normal living and it can be taken friendly everywhere as it is distributed over 50% in Korea. The pine needles consist of vitamins, protein, minerals, essential oil and enzyme related to antimicrobial activity. It has effect like high blood pressure, neuralgia and hanged over by terpene, glucokinin, rutin, apigenic acid and tannin. Also the extract of them can be used for dyeing of fabrics. However, the extract components and effects of them are not well known yet. Therefore, the purpose of this study was to investigate the volatile components of the pine needles extract and functionality. The pine needles extract was dyed into various fabrics(nylon, silk, wool and soybean) and mordanted with Al, Cu, Cr, Fe and Sn. The extracted aroma compounds were compared by gas chromatography-mass spectrometry. The major volatile compounds of pine needles verified by using SPME were alpha-pinene, beta-pinene, beta-phellandrene, caryophyllene, ethanon, benzen. A total of 15 compounds were identified by using the SPME fibers. In the UV-visible spectra, the maximum absorption of wavelength of the pine needles ethanol extract appeared at 460, 630nm for chlorophyll component and at 237, 281nm for tannin component with the pine needles distilled water extract. Most of sample showed high antibacterial effect in none mordant but wool fabric showed high antibacterial effect in mordants. The result of UV block test showed a superior ability of blocking ultraviolet ray infiltration in all sample.

구침(九鍼)의 형태와 용도에 대한 문헌연구 (Literature Study on the Conformation and Application of Nine Classical Needles)

  • 손인철;권오상;김유리;안성훈;김재효
    • Korean Journal of Acupuncture
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    • 제28권1호
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    • pp.157-169
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    • 2011
  • Objective : Nine classical needles have been recorded in oriental medical classics as a diversified instrument for acupuncture to treat patients with various symptoms. Recently, it has suggested that doctors didn't make full use of acupuncture and that poor understanding of the nine needles has caused the lack of usage. Methods : It has studied bibliographically about the conformation including a length & shape and application & usages of the nine classical needles presented in oriental medical classics. Results : Chamchim (shear needle) has 1.6 chon (寸) length, sharp apex treating fever in the head and trunk; Wonchim (roun-pointed needle) has 1.6 chon, eggshaped apex treating disease of flesh by massaging with it; Sichim (spoon needle) has 3.5 chon, thick body with round sharp apex treating weakness of Qi; Bongchim (lance needle) has 1.6 chon, a triangled apex treating chronic disease with bleeding; Pichim (stiletto needle) has 4 chon, razor sharp applying to surgery of big pus; Wonlichim (round-sharp needle) has 1.6 chon, thin body, sharp apex treating acute arthralgia syndromes; Hochim (filiform needle) has various lengths which treats various disease of meridians and organs; Jangchim (long needle) has 7 chon, sharp apex treating chronic arthralgia syndromes in deeper place of body; Daechim (large needle) has 4 chon, nail like apex applying to excrete artheredema in joints. Conclusions : The conformation of nine classical needles has been changed from those recorded in oriental medical classics since it was developed. However, the usage of nine classical needles has remained the same. Therefore it is considered that intrinsic attribute of the nine needles has preserved even though the conformation of nine classical needles has changed.