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1.
目的:探讨658 nm低能量激光照射对人牙周膜细胞增殖、碱性磷酸酶活性及纤维连接蛋白合成的影响.方法:改良组织块法体外培养人牙周膜细胞.通过658 nm激光照射人牙周膜细胞,观察能量密度为1.86 J/cm2和3.72 J/cm2激光照射后不同时间点细胞增殖效应、碱性磷酸酶活性和纤维连接蛋白的变化.结果:1.86 J/cm2和3.72 J/cm2能量密度的激光照射人牙周膜细胞,可显著促进细胞增殖效应.3.72 J/cm2能量密度的激光照射可提高人牙周膜细胞碱性磷酸酶活性;能量密度为1.86 J/cm2的激光照射人牙周膜细胞72 h后,细胞中纤维连接蛋白分泌量增加.结论:658 nm低剂量激光照射可促进人牙周膜细胞增殖;适量的低剂量激光照射人牙周膜细胞可促进其碱性磷酸酶活性及纤维连接蛋白的分泌.  相似文献   

2.
低强度532nm与633nm激光血管内照射生物效应比较   总被引:5,自引:1,他引:5  
目的:研究同等照射条件的低强度532nm与633nm激光血管内照射对家兔白细胞计数与淋巴细胞凋亡的影响,比较两种激光生物效应的特点。方法:用532nm和633nm激光对健康日本大耳白家兔血管内照射,平均照射功率均设在5mW左右,照射总能量约12J。两组家兔均于照前及照后1d、4d、7d、11d进行外周血白细胞计数,于照前及照后1d、5d进行淋巴细胞凋亡分析。结果:532nm激光照射后,家兔外周血白细胞计数表现为先显著升高后趋向恢复,633nm激光照射后白细胞计数变化类似,但与照前相比升高不明显;与照前相比,两组家免外周血淋巴细胞凋亡比例于照后1d均明显降低,照后5d均显著升高;两组家兔相比,照射后白细胞计数差别明显,但淋巴细胞凋亡比例差异不显著。结论:同等照射条件下,低强度532nm与633nm激光照射血液的生物效应相似,都可以促进白细胞的代谢更新,只是532nm激光的效应略强一些。  相似文献   

3.
本研究构建急性大鼠脊髓夹伤模型,并将大鼠随机分为单纯脊髓损伤对照组及脊髓损伤联合弱激光照射组。照射组应用810 nm波长,150 m W照射功率,照射光斑0.3 cm^2的弱激光对脊髓损伤区进行经皮照射,连续照射3天,7天或14天。应用免疫荧光、免疫印迹实验方法,测定脊髓损伤区巨噬细胞及小胶质细胞的极化表达。应用酶联免疫吸附法测定脊髓损伤区白细胞介素4的表达情况。应用坚牢蓝髓鞘染色测定两组损伤脊髓中髓鞘保留的差异。采用BBB评分对两组大鼠后肢运动功能的恢复进行评估。结果表明,810 nm弱激光对脊髓损伤区连续照射3天,7天后,可显著减少M1型巨噬细胞及其标志物诱导型一氧化氮合酶的表达,在7天时间增加M2型巨噬细胞及其标志物精氨酸酶1的表达。弱激光照射组白细胞介素4的表达明显增加。损伤后14天,弱激光照射组脊髓损伤区髓鞘保留面积比值明显提高。损伤后7天及14天时,弱激光照射组大鼠的BBB评分明显升高。该实验结果表明,810 nm弱激光经皮照射,可增加大鼠急性脊髓损伤区M2型巨噬细胞及小胶质细胞的表达,并减少脊髓损伤后的髓鞘脱失,促进脊髓损伤大鼠运动功能的恢复。  相似文献   

4.
研究578.2 nm激光照射对兔视网膜的作用特点,以新西兰白兔5只10眼为实验对象,铜蒸汽激光(578.2 nm)通过裂隙灯照射兔视网膜后极部,照射时间为100 s,光斑直径为2 mm,照射剂量分别为60 J/cm2、80 J/cm2、100 J/cm2、120 J/cm2、160 J/cm2、200 J/cm2,每组4个光斑。照后1 h及24 h进行眼底照相及光镜观察。照光后可见,随激光功率密度的增加,兔视网膜的损伤也逐渐加重,并且照后24 h的损伤要重于照后1h。80 J/cm2和60 J/cm2在照后1 h和24 h均未发现明显改变。578.2 nm激光照射白兔后的主要病理学改变位于脉络膜。因此,以578.2 nm激光作为光动力治疗眼底疾病的光源时,照射剂量不宜超过80 J/cm2。  相似文献   

5.
He-Ne激光照射对血液及其组分荧光光谱影响的实验研究   总被引:2,自引:0,他引:2  
为研究弱激光照射对人血液携氧能力的影响及机制,我们用荧光仪分别测量了He-Ne激光照射前后正常血液及其组分(血浆、红细胞)的荧光光谱,研究了激光照射导致的光谱变化,并分析了光谱变化与血液携氧能力改变的关系。实验结果显示:全血液标本在490nm及614nm附近有荧光峰值;血浆的荧光则主要分布在420-500nm之间;红细胞在500nm及614nm附近有荧光。He-Ne激光照射后,全血液及红细胞在614nm处的荧光谱都有较明显的变化,且较相似。由此可得出结论,He-Ne激光照射可影响血液的携氧能力。  相似文献   

6.
大剂量激光与免疫抑制剂对大鼠免疫功能的影响   总被引:1,自引:0,他引:1  
应用不同剂量的He—Ne激光连续14天照射健康大鼠,分别于照射后7、14,17、21、28、35天监测大鼠白细胞总数各类白细胞数目的变化。照射大鼠内眼角激光日剂量为13.2415J/cm~2以上,照射大鼠耳后凹陷部的激光日剂量为18.5381J/cm~2以上,照射大鼠脊背正中线皮肤的激光日剂量为23.8347J/cm~2以上,均可在照射后一定时期对大鼠上述指标产生不同程度的抑制作用。实验结果表明,各类白细胞对激光抑制效应的敏感性不一,敏感顺序是:嗜酸性白细胞-杆状核白细胞-分叶核白细胞淋巴细胞。作为有效大剂量町选择日剂量18.5318J/cm~2作内眼角照射,26.4830J/cm~2作耳后凹陷照射,39.7245J/cm~2作脊背正中线皮肤照射。 应用日剂量为39.7245J/cm~2的He—Ne激光照射大鼠脊背正中线皮肤,并与环孢霉素A(CsA)和硫唑嘌呤(Aza)两种免疫抑制剂配合应用,以研究大剂量激光和免疫抑制剂两者配合对大鼠白细胞总数、各类白细胞数、T、B淋巴细胞数、淋巴细胞转化刺激指数(S、I)、10~6个淋巴细胞CPM数的影响,大剂量激光和免疫抑制剂(CsA、Aza)及其配合均可在试验后一定时期对大鼠白细胞总数和各类白细胞数具有明显的抑制作用。大剂量激光和Aza可降低大鼠B淋巴细胞数。大剂量激光、CsA、Aza及激光与二者配合均可使淋巴细胞转化刺激指数(S、I)在  相似文献   

7.
郑宓  吴颖  陈威  顾青  夏欣 《现代生物医学进展》2013,13(19):3601-3607
目的:通过静脉注射光敏剂Erythrosin B联合激光照射诱导大鼠视网膜水肿模型,并观察该模型中大鼠视网膜及血管形态改变.方法:大鼠尾静脉注射光敏剂Erythrosin B后,使用532nm Nd:YAG激光(1.95±0.05 mw)照射大鼠视网膜8分钟.分别于建模后第1、2、3、5、7及14天进行眼底照相、眼底荧光造影(FFA)及视网膜光学相干断层扫描(OCT)检查.并在OCT图像上测量大鼠视网膜厚度(RT).结果:眼底照相、FFA及OCT结果显示大鼠视网膜在激光照射后可立即出现血管损伤及视网膜厚度增加,但未发现视网膜血管栓塞.激光照射前RT为219±2 μm,激光照射后第1天RT即增加至283±6μm,并在第2天到达顶峰(302±7μm),之后开始下降,至第5天恢复到激光照射前水平(234±9 μm),到第14天时视网膜发生明显萎缩,RT较激光处理前减小(198±6μm).结论:这一通过光化学反应诱导的视网膜水肿模型具有可靠及可重复性,可被运用于视网膜水肿的病理学及动力学研究.  相似文献   

8.
目的研究Q开关激光爆破术对豚鼠黑素细胞的影响及照射周边组织的变化,为临床治疗皮肤色素病变提供实验依据。方法用Q开关-YAG激光分别照射豚鼠黑色毛区及棕色毛区(波长分别用1064nm和530nm,光斑直径2mm),实验动物20只,随机分四组,分别于照射后间隔7d、10d、14d取材,照射前取材作对照,10%甲醛固定,冰冻切片,分别用HE和DOPA反应显示黑素细胞。结果照射后皮肤黑色素颗粒逐渐减少至消失,照射后30d黑毛区与棕毛区肉眼见照射区皮肤变白,毛也变白,HE染色皮肤、毛囊及毛未见黑色素颗粒,DOPA反应表皮黑色素细胞、毛囊和毛均呈阴性反应,部分豚鼠棕毛区毛及毛囊见黄色色素颗粒。结论波长1064nm和532nm Q-YAG激光对豚鼠皮肤黑色素细胞和黑色素颗粒的破坏效果显著;但对棕色色素清除效果较差。波长1064nm Q-YAG激光对豚鼠皮肤黑色素消减与照射次数有关,与照射间隔时间长短无关。  相似文献   

9.
Nd:YAG激光治疗牙周病的临床微生物学效应的研究   总被引:3,自引:0,他引:3  
本实验的在于照射Nd:YAG激光对成人牙周病患者口腔生物及其临床变化的和较广的我们将本次实验中所用24名成人牙周病患者分成为实验组16名,对照组8名,其中实验组患者给予激光照对照组则否,再照射后患者牙周囊袋中是否可采得致病将实验组分为两小组,其中激光照射第一组为照射后,仍可从囊袋中采得可培养的致病菌者,激光照射第二组则否。我们藉由直接镜检及培养法配合免疫萤光技术来分析牙周病菌,临床上则采用探针来检  相似文献   

10.
激光照射对蓖麻蚕酯酶同工酶的影响   总被引:1,自引:0,他引:1  
本文采用三种不同波长不同形式的激光照射蓖麻蚕蚕卵,经孵化后的幼虫在五龄期第二天取血,利用聚丙烯酰胺凝胶电泳法对血液中酯酶同工酶进行分析,并与对照组比较,结果表明:激光照射后的各组均发生不同的变化,说明经激光照射后能够诱发蓖麻蚕的遗传变异。  相似文献   

11.
Autoradiographic studies and scintillation counting of crypt material after pulse labelling with 3H-thymidine showed that during continuous irradiation with 290 rads/day a reduced proliferative activity is present in the crypts of rat small intestine after 1 day of irradiation and of normal activity during the remaining period (5 days) irradiation. After cessation of irradiation an increase in proliferative activity can be observed after 1 day of recovery. From the time (36–48 hr after starting of the irradiation) that the number of villus cells is reduced an expansion of the proliferation zone in the crypt was observed. Both effects last until 1 day of recovery after cessation of irradiation. The process of crypt cell maturation and of villus cell function has also been studied during and after continuous irradiation by micro-chemical enzyme analyses in isolated crypts and villi. It was found that the expansion of the proliferation zone in the crypt is accompanied by a decrease in activity of only those enzymes (i.e. non-specific esterases) which normally become active during crypt cell maturation. The activity of enzymes normally present mainly in the functional villus cells remained relatively unaffected by changes in crypt cell kinetics. A hypothesis of different regulation mechanisms of the proliferative activity in the intestinal crypt and a possible explanation of the different behaviour of various enzyme activities as a result of changes in crypt cell proliferation is discussed.  相似文献   

12.
The molecular mechanisms of laser-induced changes in the cell structure and function are not well known. The authors examined the effects of low-power laser irradiation on unnucleated pig blood platelets. The obtained results showed that laser irradiation (1–5J) caused in blood platelets lipid peroxidation (measured as thiobarbituric acid reactive substances) and super-oxide anion generation, concomitant with the release of adenine nucleotides and proteins from platelets. The maximum platelet response to laser irradiation was observed when doses of 1.8–2J were used. Our results indicate that red laser irradiation induces: (1) platelet secretory process and the release of substances stored in the specific granules (adenine nucleotides, proteins); and (2) lipid peroxidation partly due to stimulation of endogenous arachidonate and production of its metabolites reacting with thiobarbituric acid.  相似文献   

13.
Abstract— Freeze-blowing (Veech et al. 1973), focussed microwave irradiation (Stavinoha et al. 1973) and immersion in liquid nitrogen were compared as methods for stopping metabolism in order to assay in vivo levels of intermediary metabolites in developing rat brain. Freeze-blowing was superior at all ages (5. 10, 15 and 20 days post-natal). The differences between this method and immersion in liquid nitrogen were quite small in the youngest rats and increased with age. reflecting the increased time needed to freeze larger brains. Brains frozen by immersion in liquid nitrogen showed evidence of increased anaerobic metabolism, with increased fructose 1.6-diphosphate. dihydroxyacetone phosphate and lactate and decreased glucose 6-phosphate and creatine phosphate concentrations. When brain metabolism was stopped by microwave irradiation there were many differences from freeze-blown brain. Increases in fructose 1.6-diphosphate. dihydroxyacetone phosphate, ADP and AMP, and decreased in ATP and creatine phosphate were especially striking. The differences between microwave irradiation and freeze-blowing were not attributable simply to anoxia. Rather, the changes produced by this method seem to reflect the different thermal characteristics of the various enzymes which must be denatured to stop metabolism of the substrates measured. Unlike freezing in liquid nitrogen, the efficacy of microwave irradiation was not a simple function of head size, in that better results were achieved with 15- and 20-day-old than 5- or 10-day-old rats. Many glycolytic and Krebs cycle intermediates, as well as glutamate and aspartate, progressively increased over the course of development. The reasons for these increases are uncertain but are probably-related to the concomitant rises in rates of glycolysis and oxidative phosphorylation in brain.  相似文献   

14.
A nonmonotonous relationship between changes of metabolic parameters of tissues and cells of animal and radiation dose were discussed. Under acute irradiation of animals the nonmonotonous dose-response curve for metabolic parameters of tissues and cells were found. The nonmonotonous dose-response curves of metabolic and functional tissues and cells parameters were also revealed upon chronic irradiation of animals at a low dose-rate. The nonmonotonous shape of dose-response curves may be explained on the basis of nonmonotonous kind of the time-course of metabolic response after irradiation. Living cells were supposed to possess a fundamental property in response to action of different stress agents by nonmonotonous changes of cell metabolism. This response was damping in time oscillation of the value of metabolic parameters around the normal level. Amplitudes and periods of oscillations in these changes of metabolic parameters could be observed. In case of chronic irradiation at a low dose-rate the metabolic and functional parameters showed some modified oscillation during irradiation. The nonmonotonous type of changes in metabolic and functional parameters of tissue and cell by chronic low dose-rate irradiation threw some new light on the peculiarities of biological effects of chronic irradiation.  相似文献   

15.
The influence of 400 R X-irradiation on the localization and the number of mature and immature goblet cells and Paneth cells in rat duodenal epithelium has been studied. At short times after irradiation, when the total proliferative activity in the crypts of Lieberkiihn is reduced, the proportion of mature and immature goblet cells of the total number of crypt cells was increased; also an absolute increase in the number of goblet cells in the crypts was found. The immature goblet cells were localized in the lower half of the crypt as in control animals, whereas the number of the mature cells increased over the whole crypt length. When the proliferative activity of the crypt cells increases again from 12 to 48 hr after irradiation the number of both types of goblet cells decreases. Between 48 and 72 hr, when the whole crypt is involved in proliferation, a second increase of both types of goblet cells was found. However, the localization of the immature goblet cells is no longer restricted to the lower half of the crypt but they also appear at the higher cell positions. On the villus no immature goblet cells were found and the changes in the numbers of mature goblet cells do reflect the changes induced by irradiation in the goblet cell population in the crypt. The absolute number and localization of Paneth cells did not change under the experimental conditions. The findings are discussed in relation to cell proliferation and differentiation processes in intestinal crypts.  相似文献   

16.
Calculations were made based on experimental data of the variation in radiosensitivity and in cell cycle delay with age in Chinese hamster cells (Sinclair, 1967, 1968). The computed syntheses included: (a) single-dose survival curves; (b) splitdose recovery curves, the pattern of survival; and (c) two-dose survival curves, the shape of the second survival curve. It is clear that, after an initial dose, changes occur in the subsequent dose-response curve which depend upon size of dose and time after irradiation. Following rapid and apparently complete repair of sublethal injury, these changes can be attributed to progression of a partially synchronized population through phases of varying radiosensitivity. These changes may be small in some systems, but important in others. The concept of equal dose-increments after each of several dose fractions is an over-simplification and must be used with care.  相似文献   

17.
Abstract— Withdrawal of food or immobilization both led to changes in rat brain tryptophan metabolism. Brain tryptophan and 5-hydroxyindolylacetic acid concentrations both increased while changes in 5-hydroxytryptamine were much smaller. Changes were greater upon withdrawal of food. The brain tryptophan change did not appear merely to reflect an overall increase of brain amino acid concentrations, brain tyrosine concentration being only slightly increased by food withdrawal and significantly decreased upon immobilization. Plasma tryptophan did not increase. The changes in brain indole metabolism were not abolished by adrenalectomy. Results are discussed in relation to the regulation of brain serotonin metabolism.  相似文献   

18.
刘成军  韦世秀 《蛇志》1993,5(3):20-23
用~(60)钴—r 射线对蛇毒抗栓酶冻干粉针剂进行辐射灭菌,效果显著.经聚丙烯酰胺凝胶电泳鉴别、酶活性分析等项目的检测.分别比较了辐射前后蛇毒抗栓酶的质量,证明在3×10~5r 伦琴照射剂量以内,其物理化学性质不改变.动物实验表明,对药效也无影响,适用于本品的灭菌。可弥补生物制品酶制剂在高温条件下灭菌时,酶易失去活性的不足.  相似文献   

19.
Investigations were undertaken in CF1 mice to study the effects of hydroxyurea (HU) on hair matrix cell kinetics, and to assess the effects of combined administration of HU and irradiation on induction of temporary alopecia. HU 100 mg/kg was administered intraperitoneally and each animal received tritiated thymidine 0·5 μCi/g 30 min before biopsy. Serial biopsies were taken up to 48 hr after drug administration. Autoradiographs of anagen follicle squashes revealed sharp reductions in mitotic and labeling indices within 30 min. Depressed mitotic indices of 0·6–0·9% at 1–4 hr returned to normal (2·3%) after 6 hr, followed by cyclic mitotic 'overshoot', and were preceded by parallel changes in the labeling indices. HU-induced cellular damage was most marked 4 hr after HU injection, with almost complete recovery from injury observed at the 24 hr interval.
The effects of varying the time intervals from 1 to 12 hr between HU administration and irradiation (650 rads) after injection of HU 1200 mg/kg were examined. Hair loss was measured 7 days later by photomicroscopy. Cyclic maximum alopecia was found at the 1–5 and 8–12 hr intervals, with relative 'protection' occurring at the 6–7 hr time periods.  相似文献   

20.
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