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71.
Siew Han Chay A Bakr M Rabie 《American journal of orthodontics and dentofacial orthopedics》2002,122(1):95-102
In this case report, orthodontic intervention was used to move the gingival margin of a maxillary canine incisally by almost 9 mm to mimic a lateral incisor. Increasing the thickness of the labial plate of bone of the canine and subsequently increasing the thickness of the attached gingiva before extrusion prevented gingival recession at a later stage. In many situations, orthodontic treatment can achieve results that could not be attained by restorations and other means of cosmetic dentistry, especially when dealing with gingival margins and gingival height. A step-by-step approach to achieving these treatment objectives is described. 相似文献
72.
Celecoxib induces functional recovery after intracerebral hemorrhage with reduction of brain edema and perihematomal cell death. 总被引:13,自引:0,他引:13
Kon Chu Sang-Wuk Jeong Keun-Hwa Jung So-Young Han Soon-Tae Lee Manho Kim Jae-Kyu Roh 《Journal of cerebral blood flow and metabolism》2004,24(8):926-933
The selective cyclooxygenase-2 (COX-2) inhibitor has been reported to have antiinflammatory, neuroprotective, and antioxidant effects in ischemia models. In this study, the authors examined whether a selective COX-2 inhibitor (celecoxib) reduces cerebral inflammation and edema after intracerebral hemorrhage (ICH), and whether functional recovery is sustained with longer treatment. ICH was induced using collagenase in adult rats. Celecoxib (10 or 20 mg/kg) was administered intraperitoneally 20 minutes, 6 hours, and 24 hours after ICH and then daily thereafter. Seventy-two hours after ICH induction, the rats were killed for histologic assessment and measurement of brain edema and prostaglandin E2. Behavioral tests were performed before and 1, 7, 14, 21, and 28 days after ICH. The brain water content of celecoxib-treated rats decreased both in lesioned and nonlesioned hemispheres in a dose-dependent manner. Compared with the ICH-only group, the number of TUNEL-positive, myeloperoxidase-positive, or OX42-positive cells was decreased in the periphery of hematoma and brain prostaglandin E2 level was reduced in the celecoxib-treated group. Celecoxib-treated rats recovered better by the behavioral tests at 7 days after ICH throughout the 28-day period, and the earlier the drug was administered, the better the functional recovery. Evidence of similar effects in an autologous blood-injected model showed that direct collagenase toxicity was not the major cause of inflammation or cell death. These data suggest that celecoxib treatment after ICH reduces prostaglandin E2 production, brain edema, inflammation, and perihematomal cell death in the perihematomal zone and induces better functional recovery. 相似文献
73.
R K Conlee D W Barnett K P Kelly D H Han 《Metabolism: clinical and experimental》1991,40(10):1043-1047
Cocaine and exercise are both known as stressors, but little is known about the combined effects of these two treatments. In this study, rats under the influence of cocaine (12.5 mg/kg, intraperitoneally [IP]) or saline were exposed to a variety of resting conditions, as well as exercise (running, 26 m/min, 10% grade, for 30 minutes), to evaluate the amount of stress imposed by these conditions as determined by the changes in the plasma concentrations of corticosterone (C) and catecholamines (norepinephrine [NE], epinephrine [E], dopamine [DA]). After injection of saline, resting near the operating treadmill for 30 minutes caused the concentration of C to increase from 0.07 +/- 0.03 to 0.30 +/- 0.05 microgram/mL (P less than .05), compared to the increase to only 0.15 +/- 0.04 micrograms/mL after resting in a cage. This increase due to proximity to the treadmill subsided after 50 minutes. After cocaine, the 30-minute resting values were 0.70 +/- 0.15 (treadmill) and 0.55 +/- 0.13 (cage) (P less than .05), and did not subside after 50 minutes. Cocaine also increased levels of E, NE, and DA above those in saline under all rest conditions. With exercise, the value for C in saline increased to 0.61 +/- 0.18, but, in cocaine, the value went to 0.93 +/- 0.05 (P less than .05). The concentrations of E (946 +/- 74 v 603 +/- 101 pg/mL, cocaine v saline) and NE (1,027 +/- 102 v 440 +/- 153, cocaine v saline) during exercise also were exaggerated by cocaine treatment (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
74.
The effect of Panaxatriol Ginsenoside (PTGS) on Immune functions in bone marrow suppressed mice induced by injection of cyclophosphamide (CY) has been studied. Bone marrow suppressed mice were made by injection of CY (150 mg/kg) parenterally. Subcutaneous injection of PTGS three days earlier partially restored the number and the activity of bone marrow cells, significantly enhanced the production of IL-1, IL- 3 and IL- 6 like substances and promoted the reactivity of murlne spleen cells to Con-A In bone marrow suppressed mice. 相似文献
75.
C L Yu C Y Tsai S Y Hong C S Lue C C Chiu B N Chiang S H Han S R Wang 《Scandinavian journal of rheumatology》1991,20(1):8-15
Extracellular phospholipase A2 (PLA2) is a proinflammatory enzyme found especially in the inflammatory exudate to modulate blood flow to areas of antigen stimulation. In this study we found that PLA2 exerted a biphasic effect on the proliferation of phytohemagglutinin (PHA)-stimulated human mononuclear cells (PHA MNC). At low concentrations range from 0.001 to 1 U/ml, PLA2 enhanced the proliferation of PHA MNC (maximal increase was 37.0 +/- 5.67%). Conversely, at concentrations over 10 U/ml, PLA2 markedly suppressed the PHA-induced MNC proliferation (maximal decrease was 88.86 +/- 2.89%). PLA2 was non-toxic to lymphocytes after three days culture, unless the concentration was higher than 100 U/ml. The membrane polarization of PHA-stimulated lymphocytes was also increased by PLA2 at a low concentration. In addition, PLA2 displayed a similar effect on the proliferation of streptokinase-streptodornase (SK/SD) or allogeneic cell stimulated lymphocytes. The change of lymphocyte proliferation by PLA2, was parallel to the change of percentage of helper T cells. Furthermore--a CD4-rich population was proved more susceptible to PLA2 effect than a CD8-rich population. Para-bromophenacyl bromide (pBPB), an irreversible inhibitor of PLA2, abrogated the biphasic effect of PLA2 on PHA MNC proliferation. These results suggest that PLA2 plays a regulatory role on immune reactions by modulating the percentage of helper T cells. 相似文献
76.
冠心病行为模式与心理状态的相关性探讨 总被引:8,自引:1,他引:7
目的为探讨A型行为在冠心病(CoronaryHeartDisease,CHD)中的作用及与心理状态的相关性。方法对114例CHD及37例非CHD应用心理测验方法对照调查。结果发现A型行为的人易患CHD。CHDA型行为者在焦虑、抑郁、人际关系、认识、敌对性症状因子分较CHD非A型行为者有明显增高。CHD非A型行为者也具有一些特有的心理症状。结论CHD病人的行为模式与病后的某些心理表现呈正相关。 相似文献
77.
检测45例正常人和44例不同病期白血病血浆和外周血白细胞内维生素A、E、C、B12和β-胡罗卜素、叶酸浓度。结果表明,初治白血病患者血浆维生素A、β-胡罗卜素降低(P<0.01),未缓期解者血浆β-胡罗卜素和叶酸低于正常(P<0.01和P<0.05)。在初治和未缓解期患者的外周血白细胞内,维生素E、C、B12和β-胡罗卜素均显著降低(P<0.01~0.001)。而且,外周血白细胞内维生素代谢异常比血浆更为显著。提示维生素含量变化对于解释病因,预测疗效及估计预后有一定的价值。 相似文献
78.
本文从生命质量的内涵入手,分析了滥用药物的直接和间接、近期和远期的危害,通过论证得出了滥用药物必将引起人类生命质量退化的结论.以期从一个新的认识度唤起人们对滥用药物问题的重视、并由此引出了一些对医学目的以及滥用药物控制措施的思考. 相似文献
79.
80.
本文报告260例恶性肿瘤患者血清维生素A、E、C水平的测定结果。发现除慢性白血病外,蓁7种恶性肿瘤患者血清维生素A水平平均显著低于健康人(P<0.01);急性白血,肝癌、食管癌患者血清维生素E水平显著低于健康人(P<0.05);急性粒细胞白血病、急性单核细胞白血病、肝癌患者血维生素C水平显著低于健康人(P<0.01)。本研究工作为维生素A、E、C药物在肿瘤临床上的应用提供了参考。 相似文献