• Title/Summary/Keyword: protuberance

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Structural Features of Various Trichomes Developed in Salvinia natans (부유부엽성 생이가래 모용의 구조적 특징)

  • Ji, Sang-Yong;Kim, In-Sun
    • Applied Microscopy
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    • v.32 no.4
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    • pp.319-327
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    • 2002
  • Salvinia natans, an unique water fern having a small rootless body, developed three different types of trichomes throughout the plant. The most peculiar type exhibiting rows of obvious, whitish, multicellular trichome clusters was noticed in the upper surface of the floating leaves. Eight to ten branches within a cluster extended ca. $370{\sim}420{\mu}m$ from the leaf surface. No stalk cell was found, however, four large epidermal cells were discernable at the base of four central branches in the cluster. Each branch consisted of $8{\sim}10$ obliquely-oriented small cells that gradually decreased in size toward the branch tip. The second type was found in the lower surface of the floating leaves, stems, and sporocarps. Multicellular uniseriate trichomes, ca. $430{\sim}980{\mu}m$ long, were distributed all over these structures. The tip of trichome was acicular, but a semi-spheric protuberance of approximately $24{\sim}32{\mu}m$ in diameter occurred at the base of each trichome. The protuberance appeared to be firmly attached to the side of the basal cell, however, internal connection to the trichome cell itself was uncertain. The third type was similar to the second in that multicellur uniseriate trichomes with acicular tip and a protuberance at the base were present. However, the trichomes were considerably long relative to the second type, and only occurred along the surface of highly dissected, submerged leaves. A majority of the trichomes exceeded more than 2 mm in length that hung downward in the water. Regardless of trichome type, all trichomes contained a huge central vacuole with very thin cytoplasm, resulting from the fusion of several vacuoles during early trichome development. The various densely-distributed trichomes formed in Salvinia natans probably play an important role in plant buoyancy.

Surgical Treatment of Malignant Tumors in Shoulder Girdle (견갑관절 주위 악성종양의 치료경험)

  • Song, Seok-Whan;Chang, Ju-Hai;Kang, Yong-Koo;Kim, Jung-Man;Kim, Hyoung-Min;Rhee, Seung-Koo;Woo, Young-Kyun;Bahk, Won-Jong;Moon, Myung-Sang;Kim, Yang-Soo
    • The Journal of the Korean bone and joint tumor society
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    • v.1 no.1
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    • pp.68-76
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    • 1995
  • To evaluate the clinical result of surgical treatment of malignant tumors in shoulder girdle, nine patients who were treated in Department of Orthopedics, Catholic University Medical College between January 1991 and December 1993, were evaluated. There were 5 men, 4 women. The mean age at operation was 47 years(range from 22 to 64 years). Of 9 patiens, 2 were soft tissue tumors(1 MFH, 1 dermatofibrosarcoma protuberance); one was treated with forequarter amputation, and the other with wide excision, Seven were bone tumor(2 chondrosarcoma, 1 osteosarcoma, 1 MFH, 1 plasmacytoma, 1 thyroid carcinoma metastasis, 1 malignant schwannoma); one patient was treated with segmental excision of proximal humerus, 4 with Malawer type I-A resection and arthroplasty or arthrodesis, 1 with Malawer type V-B resection and arthrodesis. Five patients received adjuvant chemotherapy, with or without local radiation therapy, and one patient received radiation therapy alone. All patients have survived now, but I had local recurrence. Functional results of arthrodesis and arthroplasty were similar.

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Clinical Application of $^{18}F-FDG$ PET in Nonmelanomatous Skin Cancer (비흑색종 피부암에서 $^{18}F-FDG$ PET의 임상 이용)

  • Yoon, Joon-Kee
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.sup1
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    • pp.149-152
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    • 2008
  • Nonmelanomatous skin cancer includes basal cell carcinoma, squamous cell carcinoma, merkel cell carcinoma and dermatofibrosarcoma protuberance. So far, there have been a few reports that $^{18}F-FDG$ PET was useful in the evaluation of metastasis and therapeutic response in nonmelanomatous skin cancer, however, those are very weak evidences. Therefore, further studies on the usefulness of $^{18}F-FDG$ PET in nonmelanomatous skin cancer are required.

Larval Development of Latreutes acicularis Ortmann (Crustacea: Decapoda: Hippolytidae) Reared in the Laboratory

  • Yang, Hoi-Jeong
    • Animal cells and systems
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    • v.11 no.1
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    • pp.79-92
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    • 2007
  • Eight zoeal stages and one decapodid of the hippolytid shrimp Latreutes acicularis Ortmann, 1890 are described from laboratory-reared material hatched from egg from ovigerous females collected from Shimoda, Japan. The presence of a minute dorsomedian protuberance on the third abdominal somite, the spinules on the dorsal margin of the fourth and fifth abdominal somites, and a pair of dorsolateral spines on the fourth and fifth abdominal somites readily distinguish the larvae of L. acicularis from those of L. anoplonyx Kemp, 1914 and L. laminirostris Ortmann, 1890, the other two known larvae of Latreutes from East Asia.

Five Cases of Diphyllobothrium latum Infection (광절열두조충감염 5예)

  • 이순형;서병양
    • Parasites, Hosts and Diseases
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    • v.21 no.2
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    • pp.150-156
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    • 1983
  • Five cases of Diphyllobothrium latum infection were proved by collection of worms after treatment with bithionol, niclosamide or praziquantel, during 1975~1983. The patients were 4 males and one female aged 10~64 years residing in Seoul or Wando-gun, Chollanam-do, Korea. All of them remembered the history of eating several kinds of raw marine fish and 2 persons said they ate the raw mesh of perch, Lateolabrax japcnicus. Three amcnE them experienced abdominal pain, 2 natural discharge of a chain of segments, but none revealed any sign of anemia. The average egg size in stool varied $59~67{\times}41~48{\mu\textrm{m}}$ according to cases. The eggs were characterised by ovoid to elliptical shape, terminal operculum, and distinct abopercular protuberance. One naturally discharged segment (30cm) and 4 complete strobilae (320~680cm) with scolices obtained after treatments were examined. The morphological characters of proglottids such as rosette-form uterus with 3~6 loops, vaginal pore included in the cirrus sac, separated seminal vesicle from cirrus sac, etc. were all compatible with D. latum. These are the 7th~11th cases of D. latum infection proved by worms in Korea.

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Fretting Corrosion Behavior of Tin-plated Electric Connectors with Variation in Temperature (온도변화에 따른 주석 도금한 전기 커넥터의 미동마멸 부식 거동)

  • Oh, Man-Jin;Kang, Se-Hyung;Lee, Man-Suk;Kim, Ho-Kyung
    • Tribology and Lubricants
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    • v.30 no.3
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    • pp.146-155
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    • 2014
  • In this study, we conduct fretting corrosion tests on tin-plated brass coupons to investigate the effect of temperature on fretting corrosion for various span amplitudes. We prepare a coupled fretting corrosion specimens using a tin-plated brass coupon with a thickness of $10{\mu}m$. One specimen is a flat coupon and the other specimen is a coupon with a protuberance in 1 mm radius, which is produced using 2 mm diameter steel ball. We conduct fretting corrosion tests at $25^{\circ}C$, $50^{\circ}C$, $75^{\circ}C$, $100^{\circ}C$ by rubbing the coupled coupons together at the contact between the flat and protuberance coupons. We measure electric resistance of the contact during the fretting corrosion test period. There is increase in resistance with fretting cycles. It is found that rate of increase in electric resistance becomes faster with increase in testing temperature. Magnitude of friction coefficient increases with fretting span amplitudes. And, change in friction coefficient becomes desensitized to the increment in span amplitude. Assuming that failure cycle is the cycle with an electric resistance of $0.01{\Omega}$, we find that failure lifetime ($N_f$) decreases with increase in testing temperature. Furthermore, based on the assumption that the damage rate of the connector is inversely related to the failure cycle, we calculate the activation energy for fretting damage to be 13.6 kJ/mole by using the Arrhenius equation. We propose a method to predict failure cycle at different temperatures for span amplitudes below $30{\mu}m$. Friction coefficients generally increase with increase in span amplitude and decrease in testing temperature.

Morphologic descritions of Taenia asiatica sp. n. (신종 조충 Taenia asiatica sp.n.의 형태학적 기재)

  • 엄기선;임한종
    • Parasites, Hosts and Diseases
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    • v.31 no.1
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    • pp.1-6
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    • 1993
  • Among taenited tapeworms inferting humans though pork or beef, Taenia solium Linnaeus 1758 and Taenia sagina Goeze 1782 have already been. Based on the morphologic characteristics of adult and metacestodes of Asian Taenia saginata, the third kind of human taeniid tapeworm konwn to disdute in Asian counteries, a new spscies name of Taenia asiatica is proposed. In addition to the known biology in their intermediate hosts, T.asiatica was diffierent morphologically from Taenia saginata Goeze 1782 in having the unarmed rostellum on the scolex of adlut, the large number of 'unterinetwigs' and the existence of 'posterior protuberance'. These structures in the gravid proglottids were used as taxonmic keys in taeniid tapeworms for the first time. T. asiatica metacestode (Cysticercus viscerotropica)was different morphologically from T. saginata metacestode (Cysticercus bovis) in having wartlike formations on external surface of the bladder wall.

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Morphometric evaluation of great vein of Galen and its clinical implications

  • Grace Suganya. S;Ariharan. K;Raveendranath Veeramani;Dinesh Kumar. V;Nagarajan Krishnan
    • Anatomy and Cell Biology
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    • v.56 no.1
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    • pp.32-38
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    • 2023
  • The Galenic venous system plays a vital role in the drainage of blood from deeper parts of the brain. This venous system is contributed by many major veins. These veins are located closer to the pineal gland making the surgical approach in this region difficult. Any accidental injury or occlusion of the vein of Galen could lead to devasting results. Thus, studying the dimensions of the vein of Galen is more important. Hence, we aimed to evaluate the morphometry and trajectory to the vein of Galen. About 100 computed tomographic venography records were evaluated and the length, diameter of vein of Galen, angle between straight sinus and vein of Galen and distance from internal occipital protuberance and roof of fourth ventricle to vein of Galen were studied. The mean length and diameter of vein of Galen were 9.8±2.7 and 4.08±1.04 respectively. The mean angle between straight sinus and vein of Galen was 64.2°. The mean distance between external occipital protuberance and roof of fourth ventricle to vein of Galen were 52±6.9 and 33.3±4.5 respectively. No significant morphometric differences were observed between the age groups as well as between the sexs. The results obtained from this study may be helpful for the neurosurgeons in better understanding of the anatomy of the Galenic venous system and to adopt a safe surgical approach to improve the efficacy of the surgeries of the pineal gland and also in the region of vein of Galen.

The study on the tribological characteristics of the MoS$_{2}$ Bonded film (고체윤활용 MoS$_{2}$ Bonded film의 마찰 마모 특성 연구)

  • 류병진;양승호;김성규;유영석;유인석
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1996.04a
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    • pp.122-127
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    • 1996
  • In this paper, the effects of the film tinckness, pre-treatment and testing load on. the tribological characteristics have been studied. During the "Ring on-Disk" testing period silica-gel was used to remove the effect of humidity. As a result, increasing the film thickness revealed prolonged wear life, in the case or reasl the testing loads the dynamic friction coefficient was decreased gradually but in regarding the wear life, an intermideate contact pressure (4kgf/mm${2}$) revealed the maximum value. In regarding the surface protuberance friction an intermediate value of area fraction (60%) revealed maximum wear life. In this paper, the qualitative model in regarding the variation of the friction coefficient andworn depth was presented.presented.

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