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Cheung-Yeoul Park Su-Gwan Kim Myung-Duck Kim Tae-Gwan Eom Jung-Hoon Yoon Sang-Gun Ahn 《Journal of oral and maxillofacial surgery》2005,63(10):1522-1527
OBJECTIVES: Dental lasers have been used for uncovering submerged implants as well as decontaminating implant surfaces when treating peri-implantitis. The objective of this study was to compare the possible alterations of the smooth surface and resorbable blast material (RBM) surface implants after using NdYAG and CO(2) lasers at various energies. MATERIALS AND METHODS: Ten smooth surface implants and 10 RBM surface implants were used. Two smooth surface implants and 2 RBM surface implants served as a control group that was not lased. The remaining implants were treated using NdYAG and CO(2) lasers. The surface of each implant was treated for 10 seconds on the second and third threads. The smooth surface implants (group 1) were treated using a pulsed contact NdYAG laser at power settings of 1, 2, 3.5, and 5 W, which are commonly used for soft tissue surgery; the corresponding energy and frequency were 50 mJ and 20 Hz, 100 mJ and 20 Hz, 350 mJ and 10 Hz, and 250 mJ and 20 Hz, respectively. The group 2 RBM implants were treated using a pulsed contact NdYAG laser. The group 3 smooth surface implants were treated using a pulsed wave non-contact CO(2) laser at 1, 2, 3.5, and 5 W, and the group 4 RBM implants were treated using a pulsed wave non-contact CO(2) laser. Data were analyzed using scanning electron microscopy. RESULTS: The control surface was very regular and smooth. After NdYAG laser treatment, the implant surface showed alterations of all the surfaces. The amount of damage was proportional to the power. A remarkable finding was the similarity of the lased areas on the smooth and RBM surfaces. CO(2) laser at power settings of 1.0 or 2.0 W did not alter the implant surface, regardless of implant type. At settings of 3.5 and 5 W, there was destruction of the micromachined groove and gas formation. CONCLUSION: This study supports that CO(2) laser treatment appears more useful than NdYAG laser treatment and CO(2) laser does not damage titanium implant surface, which should be of value when uncovering submerged implants and treating peri-implantitis. 相似文献
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Ho-Seong Han Jai Young Cho Yoo-Seok Yoon 《Journal of hepato-biliary-pancreatic sciences》2009,16(4):427-432
Many studies have recently reported on laparoscopic liver resection, although its development has been slow compared to laparoscopy in other fields. The indications for the location of laparoscopic liver resection have previously been limited to easily accessible lesions. Performing laparoscopic liver resection in the posterior and superior parts of the liver has been considered difficult due to inadequate exposure, the poor operative field and the difficulty with parenchymal dissection. Flexible endoscopy, high definition imaging and various kinds of equipment for parenchymal transection have been introduced for clinical use. In addition, much experience with this procedure has been accumulated at many centers. Accordingly, there are an increasing number of reports on laparoscopic liver resection in difficult locations. At our institution, the location of the tumor is no longer a limitation to laparoscopic liver resection. However, for safer laparoscopic liver resection, the patient positioning and trocar placement should be individualized according to the tumor location. The type of resection also may depend on the remaining liver’s functional capacity. We describe here the technical considerations for performing laparoscopic liver resection, including the technical considerations for performing laparoscopic liver resection for lesions located in the postero-superior segments of the liver. 相似文献
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Chang Y Jung Hyo S Choi Jin S Ju Hyo S Park Tae G Kwon Yong C Bae Dong K Ahn 《The journal of pain》2006,7(10):747-756
The present study investigated the role of central metabotropic glutamate receptors (mGluRs) in interleukin-1beta (IL-1beta)-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230 to 280 g. After administration of 0.01, 0.1, 1, or 10 pg of IL-1beta into a subcutaneous area of the vibrissa pad, we examined the withdrawal behavioral responses produced by 10 successive trials of an air-puff ramp pressure applied ipsilaterally or contralaterally to the IL-1beta injection site. Subcutaneous injection of IL-1beta produced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Intracisternal administration of CPCCOEt, a mGluR1 antagonist, or MPEP, a mGluR5 antagonist, reduced IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. Intracisternal administration of APDC, a group II mGluR agonist, or L-AP4, a group III mGluR agonist, reduced both IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. The antiallodynic effect, induced by APDC or L-AP4, was blocked by intracisternal pretreatment with LY341495, a group II mGluR antagonist, or CPPG, a group III mGluR antagonist. These results suggest that groups I, II, and III mGluRs differentially modulated IL-1beta-induced mechanical allodynia, as well as mirror-image mechanical allodynia, in the orofacial area. PERSPECTIVE: Central group I mGluR antagonists and groups II and III mGluR agonists modulate IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Therefore, the central application of group I mGluR antagonists or groups II and III mGluR agonists might be of therapeutic value in treating pain disorder. 相似文献
6.
目的评估十二指肠-空肠导管(Endoluminal Duodeno-Jejunal Tube,EDJT)在活体猪实验动物模型中减缓体重增加的可行性,及其在中短期生存中的安全性。方法本项研究共用8只45kg重的Yorkshire猪,其中3只置入180emEDJT,1只置入360cm EDJT,另4只猪作为对照组。切开十二指肠,将EDJT导管缝合固定在十二指肠近Vater壶腹起始处。结果评估全部猪的不适反应和体重,每日一次,共7周,未发现严重并发症发生。术后7周3组动物的平均体重变化百分率:对照组、180cm组和360cm组分别是22.5%,6%和-2.8%。EDJT组(180cm组、360cm组)体重增加明显减慢,与对照组相比,有统计学意义(P=0.05)。结论EDJT可以安全使用,无肠梗阻、肠套叠或胰腺炎等并发症发生。EDJT可明显减缓体重增加。 相似文献
7.
Epidemiologic studies have demonstrated that trans fat intake increases the risk of some chronic diseases. We hypothesize that trans fat intake would increase the risk of cardiovascular disease and type 2 diabetes mellitus by changing the lipid profile in plasma, the secretion of adipokines in adipose tissue, and the insulin sensitivity. Accordingly, the major objective of present study was to investigate the effect of dietary intake of trans fat on lipid profile, insulin sensitivity, and adipokine levels in plasma. Two groups of Wistar rats were fed a diet containing 4.5% trans fat or a control diet containing no trans fat for 16 weeks. Fasting glucose level was monitored every 2 weeks. At the end of feeding experiment, blood, heart, kidney, liver, omental adipose tissue, and semitendinosus muscle were collected. The trans fat content in organs, lipid profile, adipokine, insulin, and glucose levels in plasma were analyzed. The trans fat content in adipose tissue, heart, kidney, liver, and muscle of rats fed trans fat were 169.9, 0.6, 1.2, 1.7, and 2.5 mg/g samples, respectively. The trans fat content in these organs contributed to 15.9%, 1.2%, 2.3%, 4.3%, and 6.1% of the total fat, respectively. The plasma glucose level, insulin level, and insulin sensitivity index were not significantly different between the trans fat and control groups. The results indicated that trans fat intake might not be related to insulin resistance. However, lipid profile and plasma adipokine levels were significantly changed after trans fat feeding. The trans fat fed group showed significantly lower total cholesterol and high-density lipoprotein cholesterol levels than the control group. The decreased high-density lipoprotein cholesterol level may indicate the detrimental effect of trans fat intake on lipid profile. Adiponectin and resistin levels were significantly higher in the trans fat group than the control group. Leptin levels were significantly lower in the trans fat group than the control group. The results indicated that dietary intake of trans fat can significantly change the adipokine levels, but the possible links between adipokine level change caused by trans fat intake and metabolic effects of this change need further investigations. 相似文献
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The coexistence of otosclerosis and endolymphatic hydrops in the temporal bone have been described; however, the mechanism for the development of endolymphatic hydrops in otosclerosis remains unknown. Among 128 temporal bones with otosclerosis, involvement of the vestibular aqueduct by otosclerosis was observed in four temporal bones from two patients. In all four, the vestibular aqueduct was filled with active otosclerotic foci; the lumen of the endolymphatic duct and sac was narrowed as a result of fibrosis, and endolymphatic hydrops, more severe in the pars inferior than the pars superior, was observed. Collapse of the ductus reuniens and dilated saccule was seen in three temporal bones. Our study indicates that otosclerotic obstruction of the vestibular aqueduct may create a disturbance of the outflow and/or absorption of endolymph, leading to the development of endolymphatic hydrops and Meniere's disease, thus supporting the theory of longitudinal flow of endolymph. 相似文献
10.
Hea-Young P. Choo Hea-Ran Yoon Hwha-Soon Park Dong-Hyun Kim Jongsei Park Dong H. Kim 《Archives of pharmacal research》1998,21(2):168-173
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06≈5.5 μM. 相似文献