• Title/Summary/Keyword: retrograde channel

Search Result 14, Processing Time 0.019 seconds

Endoscopic Balloon Dilatation of Nasopharyngeal Stenosis in a Dog

  • Hwang, Ji-Hye;Kim, Jae-Hoon;Lee, Young-Won;Song, Kun-Ho;Seo, Kyoung-Won
    • Journal of Veterinary Clinics
    • /
    • v.33 no.6
    • /
    • pp.372-375
    • /
    • 2016
  • A four-year old, intact male, mixed-breed dog had a history of chronic snoring sound and dyspnea. Based on the results of computed tomography, the patient was diagnosed as nasopharyngeal stenosis. Balloon dilatation in the area of stenosis was performed using a balloon dilator inserted retrograde fashion through the working channel of an endoscope. Clinical signs were relieved but reappeared after 3 weeks. Thirty-four days following the first balloon dilatation treatment, a second procedure was performed; the balloon catheter was inserted in antegrade fashion through the left nostril and was filled with contrast agent under fluoroscopic guidance. Because of the relapse of clinical signs after 6 months, the patient received additional balloon dilatation procedure by the antegrade approach. At the one-year follow-up, the owner said that the clinical signs of nasopharyngeal stenosis had been completely resolved. Balloon dilatation could be a minimally invasive and effective treatment for nasopharyngeal stenosis, although the repetition of the procedure may be required.

A study on characteristics of the scaled SONOSFET NVSM for Flash memory (플래시메모리를 위한 scaled SONOSFET NVSM 의 프로그래밍 조건과 특성에 관한 연구)

  • 박희정;박승진;홍순혁;남동우;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.07a
    • /
    • pp.751-754
    • /
    • 2000
  • When charge-trap SONOS cells are used flash memory, the tunneling program/erase condition to minimize the generation of interface traps was investigated. SONOSFET NVSM cells were fabricated using 0.35$\mu\textrm{m}$ standard memory cell embedded logic process including the ONO cell process. based on retrograde twin-well, single-poly, single metal CMOS process. The thickness of ONO triple-dielectric for memory cell is tunnel oxide of 24${\AA}$, nitride of 74 ${\AA}$, blocking oxide of 25 ${\AA}$, respectively. The program mode(Vg: 7,8,9 V, Vs/Vd: -3 V, Vb: floating) and the erase mode(Vg: -4,-5,-6 V, Vs/Vd: floating, Vb: 3V) by modified Fowler-Nordheim(MFN) tunneling were used. The proposed programming condition for the flash memory of SONOSFET NVSM cells showed less degradation($\Delta$Vth, S, Gm) characteristics than channel MFN tunneling operation. Also the program inhibit conditions of unselected cell for separated source lines NOR-tyupe flash memory application were investigated. we demonstrated that the program disturb phenomenon did not occur at source/drain voltage of 1 V∼4 V and gate voltage of 0 V∼4.

  • PDF

Neuroprotective Effect of Phenytoin and Hypothermia on a Spinal Cord Ischemic Injury Model in Rabbits (토끼의 척수 허혈 손상 모델에서 페니토인과 저체온의 신경 보호 효과의 비교)

  • Oh, Sam-Sae;Choe, Ghee-Young;Kim, Won-Gon
    • Journal of Chest Surgery
    • /
    • v.41 no.4
    • /
    • pp.405-416
    • /
    • 2008
  • Background: Spinal cord ischemic injury during thoracic and thoracoabdominal aortic surgeries remains a potentially devastating outcome despite using various methods of protection. Neuronal voltage-dependent sodium channel antagonists are known to provide neuroprotection in cerebral ischemic models. This study was designed to compare the neuroprotective effects of phenytoin with those of hypothermia in a rabbit model of spinal cord ischemia. Material and Method: Spinal cord ischemia was induced in New Zealand white rabbits by means of infrarenal aortic cross clamping for 25 minutes. Four groups of 8 animals each were studied. The control group and the hypothermia group received retrograde infusion of saline only ($22^{\circ}C$, 2 mL/min); the normothermic phenytoin group and the hypothermicphenytoin group received retrograde infusion of 100 mg of phenytoin at different rectal temperatures ($39^{\circ}C$ and $37^{\circ}C$, respectively) during the ischemic period. The neurologic function was assessed at 24 and 72 hours after the operation with using the modified Tarlov criteria. The spinal cords were harvested after the final neurologic examination for histopathological examination to objectively quantify the amount of neuronal damage. Result: No major adverse effects were observed with the retrograde phenytoin infusion during the aortic ischemic period. All the control rabbits became severely paraplegic, Both the phenytoin group and the hypothermia group had a better neurological status than did the control group (p < 0.05). The typical morphological changes that are characteristic of neuronal necrosis in the gray matter of the control animals were demonstrated by means of the histopathological examination, whereas phenytoin or hypothermia prevented or attenuated these necrotic phenomena (p < 0.05). The number of motor neuron cells positive for TUNEL staining was significantly reduced, to a similar extent, in the rabbits treated with phenytoin or hypothermia. Phenytoin and hypothermia had some additive neuroprotective effect, but there was no statistical significance between the two on the neurological and histopathological analysis. Conclusion: The neurological and histopathological analysis consistently demonstrated that both phenytoin and hypothermia may afford significant spinal cord protection to a similar extent during spinal cord ischemia in rabbits, although no significant additive effects were noticed.

A Study on the Characteristics and Programming Conditions of the Scaled SONOSFET NVSM for Flash Memory (플래시메모리를 위한 Scaled SONOSFET NVSM의 프로그래밍 조건과 특성에 관한 연구)

  • 박희정;박승진;남동우;김병철;서광열
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.11
    • /
    • pp.914-920
    • /
    • 2000
  • When the charge-trap type SONOS(polysilicon-oxide-nitride-oxide-semiconductor) cells are used to flash memory, the tunneling program/erase condition to minimize the generation of interface traps was investigated. SONOSFET NVSM(Nonvolatile Semiconductor Memory) cells were fabricated using 0.35 ㎛ standard memory cell embedded logic process including the ONO cell process, based on retrograde twin-well, single-poly, single metal CMOS(Complementary Metal Oxide Semiconductor) process. The thickness of ONO triple-dielectric for the memory cell is tunnel oxide of 24 $\AA$, nitride of 74 $\AA$, blocking oxide of 25 $\AA$, respectively. The program mode(V$\_$g/=7, 8, 9 V, V$\_$s/=V$\_$d/=-3 V, V$\_$b/=floating) and the erase mode(V$\_$g/=-4, -5, -6 V, V$\_$s/=V$\_$d/=floating, V$\_$b/=3 V) by MFN(Modified Fowler-Nordheim) tunneling were used. The proposed programming condition for the flash memory of SONOSFET NVSM cells showed less degradation(ΔV$\_$th/, S, G$\_$m/) characteristics than channel MFN tunneling operation. Also, the program inhibit conditins of unselected cell for separated source lines NOR-type flash memory application were investigated. we demonstrated that the phenomenon of the program disturb did not occur at source/drain voltage of 1 V∼12 V and gate voltage of -8 V∼4 V.

  • PDF