• 제목/요약/키워드: Spontaneously

검색결과 1,162건 처리시간 0.023초

A Polymer Interface for Varying Electron Transfer Rate with Electrochemically Formed Gold Nanoparticles from Spontaneously Incorporated Tetrachloroaurate(III) Ions

  • Song, Ji-Seon;Kang, Chan
    • Bulletin of the Korean Chemical Society
    • /
    • 제28권10호
    • /
    • pp.1683-1688
    • /
    • 2007
  • This paper presents a novel simple method for introducing gold nanoparticles in a poly(4-vinylpyridine) (PVP) polymer layer over a glassy carbon (GC) electrode with the aim of forming a tunable electrochemical interface against a cationic ruthenium complex. Initially, AuCl4 ? ions were spontaneously incorporated into a polymer layer containing positively charged pyridine rings in an acidic media by ion exchange. A negative potential was then applied to electrochemically reduce the incorporated AuCl4 ? ions to gold nanoparticles, which was confirmed by the FE-SEM images. The PVP layer with an appropriate thickness over the electrode blocked electron transfer between the electrode and the solution phase for the redox reactions of the cationic Ru(NH3)6 2+ ions. However, the introduction of gold nanoparticles into the polymer layer recovered the electron transfer. In addition, the electron transfer rate between the two phases could be tuned by controlling the number density of gold nanoparticles.

은행잎 추출성분이 고혈압쥐의 뇌중 신경전달물질 함량에 미치는 영향 (Effects of Ginkgo biloba Leaf Extracts on the bevels of Neurotransmitters in the Spontaneously Hypertensive Rat Brain)

  • 박혜영;주지연;김명희;신정희
    • Biomolecules & Therapeutics
    • /
    • 제3권1호
    • /
    • pp.28-33
    • /
    • 1995
  • Effects of Ginkgo biloba leaf extract (GBE) and its components kaempferol-coumaroyl glucosyl rhamnoside (Kc), quercetin-coumaroyl glucosyl rhamnoside (Qc), ginkolide (G) and bilobalide (B) on blood pressure and on the levels of neurotransmitters in the spontaneously hypertensive rat brain were examined. Blood pressure decreased about 10 mmHg after administration of GBE but without significance. The concentration of norepinephrine increased (3 times) and that of DOPAC was decreased (38%) after administration of Qc. And 3-MT concentration was increased (36%) by Kc administration in striatum. While Qc administration increased the concentration of Ach (260%) and Ch(29%) significantly, B administration increased Ch concentration in cerebral cortex.

  • PDF

개에서 골육종의 절제술과 cisplatin 병용치료 3례 (Canine Osteosarocoma Treated by Surgery in Combination with Cisplatin in Three Dogs)

  • 권오경;홍성혁
    • 한국임상수의학회지
    • /
    • 제17권1호
    • /
    • pp.256-260
    • /
    • 2000
  • Two dogs with spontaneously developing osteosarcoma of the extremities and one dogs with spontaneously developing osteosarcoma of the mandible were referred to the University of Tokyo Veterinary Medical Center. Three dogs were diagnosed as osteosarcoma by clinical sign, radiography, and histological examination. After diagnosis, two dogs was treated by amputation and one dog by partial mandibulectomy. Three weeks after two surgery, all dogs administered cisdiamminedichloroplatinum (cisplatin) chemotherapy 40-50 mg/$m^2$, IV of body surface. After cisplatin therapy, dog 1 and dog 3 survived without overt metastasis. Dog 2 died of metastatic disease. The survival times of dog 1, dog 2, and dog 3 were estimated to be 69.5, 36.3 and 66.4 weeks, respectively. It was thought that the surgery in combination with cisplatin chemotherapy was a useful method to treat a canine osteosarocoma.

  • PDF

황금(黃芩), 황연(黃連), 황백(黃柏) 혼합물(混合物) 전탕액(煎湯液)이 자연발증(自然發證) 고혈압(高血壓) 백서(白鼠)의 혈압(血壓)에 미치는 영향(影響) (Effects of a Mixture of Scutellariae Radix, Coptidis Rhizoma, Coptidis Rhizoma on the Blood Pressure in Spontaneously Hypertensive Rats)

  • 유윤조;이호섭
    • 대한한의학회지
    • /
    • 제20권2호
    • /
    • pp.141-145
    • /
    • 1999
  • The aim of this experiment was to investigate the effects of a mixture of Scutellariae Radix, Coptidis Rhizoma and Coptidis Rhizoma water extracts on the blood pressure, plasma renin activity, plasma levels of aldosterone and atrial natriuretic peptide (ANP) in spontaneously hypertensive rats (SHR). The results of this study were as follows: 1. Systolic blood pressure decreased significantly after the administration of a mixture of Scutellariae Radix, Coptidis Rhizoma, and Coptidis Rhizoma water extract 0.2 ml/200g. 2. Plasma renin activity and plasma levels of ANP were not changed after the administration of a mixture of Scutellariae Radix, Coptidis Rhizoma and Coptidis Rhizoma water extracts, 3. Plasma levels of aldosterone was increased significantly after the administration of a mixture of Scutellariae Radix, Coptidis Rhizoma and Coptidis Rhizoma water extracts 0.1 ml/200g.

  • PDF

경막외 혈액봉합술로 치험한 자발성 두개내 저압 -증례 보고- (Spontaneous Intracranial Hypotension Treated with Epidural Blood Patch -A case report-)

  • 문동언;김병찬;김영주;이광수
    • The Korean Journal of Pain
    • /
    • 제10권1호
    • /
    • pp.109-112
    • /
    • 1997
  • Spontaneous intracranial hypotension(SIH) is a rare syndrome of spontaneously occurring postural headache associated with low CSF pressure. It usually occur without evidence of any preceeding events such as lumbar puncture, back trauma, operative procedure, or medical illness. This syndrome usually resolves spontaneously or with strict bed rest. When the headache persists or is incapacitating, more aggressive treatment may be necessary. Autologous epidural blood patch is highly effective in the management of SIH. We experienced a case of SIH with downward displacement of brain in MRI and successfully treated with epidural blood patch.

  • PDF

포도종자유 급여가 본태성고혈압쥐의 혈청지질 성분에 미치는 영향 (Effect of Dietary Grapeseed Oil on Serum Lipids in Spontaneously Hypertensive Rats)

  • 최혁준
    • Journal of Nutrition and Health
    • /
    • 제23권7호
    • /
    • pp.467-476
    • /
    • 1990
  • This study was performed to investigate the effects of different fat diets on the serum lipid composition and on the morphology of liver tissue of the spontaneously hypertensive rats(SHR), Rats were fed for 17 weeks one of four fat diets, control(corn oil : beef tallow=1:1), beef tallow, grapeseed oil and soybean oil. Blood was withdrawn by heart puncture from each SHR, and used to determine the serum levels of total cholesterol, HDL-cholesterol, trigly ceride and phospholipid. No significant difference in body weight was observed in all diet groups. the total serum cholesterol was significantly lower in SHR fed grapeseed oil than that of other groups. The cholesterol lowering effect of grapeseed oil seemed to results from its high contents of phytosterol and linoleic acid. Also, serum HDL-cholesterol, triglyceride and phospholipid contents were low in all the groups. photochemical microscopic observations of the liver tissue revealed the congestion of sinosoid which is regarded as the characteristics of SHR, but no significant difference was observed among the groups.

  • PDF

선천성 고혈압 쥐의 고혈압 현상과 중추 도파민 신경계 활성의 상관성 (Relationship between Hypertension and Central Dopaminergic Neural Activity in Spontaneously Hypertensive Rats)

  • 김경만;고광호
    • Environmental Analysis Health and Toxicology
    • /
    • 제7권1_2호
    • /
    • pp.59-65
    • /
    • 1992
  • The role of central dopaminergic neural activity for the maintenance of hypertension was tested. Two groups of animals were prepared; 1) Spontaneously hypertensive rats (SHR) at 14 weeks of age which reveal hypertension and 2) age-matched normotensive Wistar Kyoto rats (WKY). Blood pressures and dopamine turnover rate were measured from animals in each group. Dopamine turnover rate was determined in four brain regions such as telence-phalon, hypothalamus/thalamus, midbrain and pons/medulla, from concentration of dopamine at time zero, 1 and 2 hours after alpha-methyl-para-tyrosine (AMPT) was injected into animals. In SHR dopamine turnover rate was greater than normotensive rats in only midbrain. The result from the present study implicates that dopaminergic neural activity in midbrain may be positively coupled to the manifestation of hypertension in SHR.

  • PDF

Spontaneously Resolved Lumbar Artery Injury after Blunt Trauma

  • Nam, Seung Hyuk;Ryu, Je Il;Cheong, Jin Hwan;Park, Ki-Chul;Ro, Sun Kyun
    • Journal of Trauma and Injury
    • /
    • 제33권2호
    • /
    • pp.124-127
    • /
    • 2020
  • Major bleeding caused by vascular injuries of the abdominal aorta or its branches after blunt trauma often leads to mortality or major morbidity. We report a case that lumbar artery injury following blunt trauma was spontaneously resolved without any surgical or interventional treatment. Lumbar artery injury after blunt trauma could be treated conservatively without surgical or interventional treatment in a selected case. When an aortic or its branch injury was suspicious, diagnostic angiograms in the setting of interventional treatment may be helpful to decide an appropriate treatment modality.

Zno 버퍼층을 이용한 자발적 초격자구조를 갖는 IGZO 박막의 결정화 (Crystallization of IGZO thin film with spontaneously formed superlattice structure induced by Zno buffer layer)

  • 서동규;공보현;조형균
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
    • /
    • pp.4-4
    • /
    • 2010
  • Single-crystalline IGZO (Indium-Gallium-Zinc oxide) was fabricated on c-sapphire substrate. Single crystal ZnO was used as a buffer layer, and post-annealing was treated in $900^{\circ}C$ for crystallization of IGZO. Crystallized IGZO formed superlattice structure spontaneously induced to c-axis direction by ZnO butTer layer, the composition of IGZO was varied by amount of ZnO. Crystallinity and composition of IGZO was analyzed by X-ray Diffraction and Transmission Electron Microscopy.

  • PDF

선천성 고혈압 쥐에서 고혈압 지속현상과 중추신경계 노르아드레날린성 신경활성과의 상관성 (Relationship between Maintenance of Hypertension and Central Noradrenergic Nervous System Activity in Spontaneously Hypertensive Rats)

  • 고광호;신재수;김미영
    • 약학회지
    • /
    • 제30권6호
    • /
    • pp.334-342
    • /
    • 1986
  • The relationship between the maintenance of hypertension and the central noradrenergic nervous system activity in spontaneously hypertensive rats (SHR) was studied. The norepinephrine turnover rates in 5 brain areas; telencephalon, hypothalamus/thalamus, midbrain, pons/medulla, cerebellum as a measure of noradrenergic neuronal activity were measured at the ages of 14 weeks in SHR and normotensive Wistar rats. In 14-week old SHR, blood pressure was significantly higher than in normotensive rat, and central norepinephrine turnover rates were significantly greater in telencephalon, hypothalamus/thalamus, midbrain. There were no differences between norepinephrine turnover rates in pons/medulla, cerebellum of SHR and those of normotensive rats.

  • PDF