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1.
Immunomodulatory effect of laser on whole body exposure.   总被引:2,自引:0,他引:2  
All biomedical laser applications are based on the interaction of laser light with biological system. During the past decade considerable evidence has accumulated demonstrating that non-thermal exposure to laser can elicit cellular changes in the immune system. In the present study, we have analyzed the effect of laser on immune response in rats. A group of rats were exposed to 0.225 mu j/cm2 for 90 min for 3 days in specially designed fiberglass chambers. The whole body exposure of rats of He-Ne laser modulated both the humoral and cellular responses to tetanus toxoid stimulation. Plain red light used as a control for red laser light showed an appreciable degree of response as compared to the control groups, but not to the extent of the response to laser. Non-responders turned responders after exposure to laser. There was no response in unimmunized groups when exposed to laser and red light alone. The early and heightened immune response and proliferation of lymphocytes after exposure to laser is suggestive of a complex interaction at the cellular immune response level.  相似文献   

2.
The effect of red and white light on ethylene production was investigated in several plant species. In most cases light inhibited ethylene production. However, stimulation or no effect were also observed in a few species. In those plants where light inhibited ethylene synthesis, the effect of red light was much stronger than that of white light.Both red and white light inhibited ethylene production in green and etiolated seedlings and green leaves of Impatiens balsamina L. The inhibitory effect of red light was stronger than that of white light and much more pronounced when the plants were pretreated with ACC. The effect of red light could be reversed by far-red light. These results suggest that light affects the ethylene forming enzyme (EFE) activity and that its action is mediated by phytochrome.  相似文献   

3.
4.
Summary Unrolling of etiolated wheat leaf segments is stimulated by short periods of exposure to red light. Both gibberellic acid and kinetin will stimulate unrolling in the dark, whereas abscisic acid (ABA) inhibits the unrolling response to these two hormones and to red light. Exposure to 5 minutes of red light leads to a rapid increase in endogenous gibberellin levels in etiolated wheat leaves, and this increase is followed by a rapid decline. Pre-treatment with ABA inhibits the increase in gibberellin levels in response to red light, but the ihibitory effect of ABA on unrolling cannot be ascribed only to its effect on gibberellin levels. Pre-treatment with red light reduces the lag-phase in chlorophyll development when wheat leaf segments are subsequently exposed to white light; the effect of red light may be replaced by pre-treatment with kinetin, but gibberellic acid is relatively ineffective in this respect.  相似文献   

5.
Blocks of molar teeth and bisected knee joints from rats of 7-21 days were embedded, without previous decalcification, in tropical grade ester wax. Serial sections were cut at settings of 3-25μ on a base sledge microtome equipped with a Jung extra hard steel knife with a tool-edged profile. The sections were supported with Sellotape during actual cutting and were then coated with a 2% celloidin solution. Chloroform was used to free the sections from the Sellotape. The distribution of alkaline phosphatase activity in the knee joints and teeth was demonstrated in these sections with the coupled-azo dye technique of Gomori, using Brentamine fast red T.R. salt.  相似文献   

6.
胶原诱导型关节炎大鼠的关节影像学特点   总被引:2,自引:0,他引:2  
目的旨在分析CIA X线片四肢关节的破坏特点,揭示CIA大鼠关节破坏的规律,为规范评分方案提供依据。方法采用П型胶原和弗氏完全佐剂皮下注射清洁级Wistar大鼠,造模成功(每批10只,共3次)后第35天行全身X线钼靶照片,以正常组作为对照、每只大鼠评价96块骨破坏(erosion)和100个关节间隙(joint space narrowing,JSN);处死动物,取左前肢和右后肢近端第3足趾关节苏木素-伊红(HE)染色,评价中性粒细胞、淋巴细胞、浆细胞浸润、滑膜增生和软骨破坏的情况。结果造模成功后CIA大鼠关节出现明显的红肿,活动受限;HE病理显示,CIA关节存在明显的中性粒细胞、淋巴细胞和浆细胞浸润,滑膜增生,纤维组织增生,软骨破坏;X线片分析结果显示:①广泛性骨质疏松,边缘性骨质侵蚀,关节间隙狭窄或增宽,部分踝关节间隙消失,关节相互融合甚至骨性强直。②67%的骨出现erosion,JSN影响为78%,关节破坏以中、重度为主;③远端、近端趾间关节和踝关节发病率高,损害严重,掌趾关节发病率低,破坏较轻。④后肢关节破坏重于前肢(P〈0.01),左右肢没有显著性差异(P〉0.05)。结论①滑膜是CIA炎症反应启动的主要病灶,与骨交界的滑膜和血管翳造成了CIA的骨质破坏;②CIA影像学表现关节破坏严重,以远端、近端趾间关节和踝关节为主,这些关节可作为评价破坏程度的选择。本研究对于深入CIA关节破坏的病因病理和进一步规范X线片评分方案具有一定意义。  相似文献   

7.
For the formation of chloroplasts in excised wheat roots blue light is necessary, but red light enhances the blue light effect. Intensity-response relationships and action spectra have been determined for the specific blue light effect as well as for the effect of red light when given before or after blue light. The longest wave length giving a blue light effect is about 500 nm. The spectrum shows a peak at about 450 nm, and a considerable effect extends down to 368 nm, the shortest wave length tested. The photoreceptor mechanism for the “blue reaction” is thought to be related to that of certain phototropisms and chloroplast movements, and to that involved in carotenoid synthesis in certain fungi. The active pigment is thought to be either a carotenoid or a flavoprotein, probably the latter. The effect of red light shows similar action spectra whether the red light is given before or after the blue, and they are consistent with protochlorophyll absorption. However, much less light is needed to produce a detectable response when the red light is given before the blue light than after. Because of the similarity of the spectra phytochrome may also be involved in the response to red light when given before blue. Far-red reversal has not been tested. The results are discussed in relation to the development of chloroplasts in leaves.  相似文献   

8.
The effect of red and far red light having a low intensity on Escherichia coli growth was studied. The growth accelerated when the culture was irradiated with the light at a dose of 1--4 X 10(3) J/m2. When the light of the two spectral regions was used together, the effect depended on the dose and order of the irradiation. It is possible that receptors for red light and for far red light interact in E. coli cells.  相似文献   

9.
The effect of blue light on energy levels in epidermal strips   总被引:1,自引:0,他引:1  
Red light applied together with blue enhanced stomatal opening in epidermal strips of Commelina communis L. more than red light alone. In red light, stomatal opening was enhanced by exogenously applied ATP and was inhibited by 3-(3,4-dichlorophe-nyl)-l,l-dimethylurea (DCMU), while in the presence of blue light external ATP was almost without effect, and DCMU stimulated stomatal opening. Blue light increased the ATP levels in the epidermal strips. DCMU diminished the amount of ATP in both red light and red + blue light treatments, but did not abolish the stimulatory effect of blue light. Blue light also stimulated the respiration rate of the epidermal strips. Rotenone, which inhibited stomatal opening and respiration rate, abolished the effect of blue light in both processes. These results imply that blue light increases the ATP levels by stimulation of oxidative phosphorylation.  相似文献   

10.
Four days oldAmaranthus seedlings responded to light treatment with an increase of amaranthin accumulation. With increasing irradiation time, red light caused a saturation effect. Blue light induced a high irradiation response. The blue light effect was reversible to a certain extent by far-red irradiation given at the end of the treatment with blue light. Intermittent red light (3 h red light, 3 h dark, …) caused a higher amaranthin accumulation than 24 h continuous red light. Results obtained with red and blue light are discussed on the basis of the phytochrome system.  相似文献   

11.
Wada M  Furuya M 《Plant physiology》1972,49(2):110-113
When filamentous protonemata of Adiantum capillus-veneris L. precultured under continuous red light were transferred to the dark, the apical cell divided about 24 to 36 hours thereafter. The time of the cell division was delayed for several hours by a brief exposure to far red light given before the dark incubation. The effect of far red light was reversed by a small dose of red light given immediately after the preceding far red light. The effects of red and far red light were repeatedly reversible, indicating that the timing of cell division was regulated by a phytochrome system. When a brief irradiation with blue light was given before the dark incubation, the cell division occurred after 17 to 26 hours in darkness. A similar red far red reversible effect was also observed in the timing of the blue light-induced cell division. Thus, the timing of cell division appeared to be controlled by phytochrome and a blue light-absorbing pigment.  相似文献   

12.
Abstract. This paper describes the effect of prolonged treatments with red or blue light on the capacity of the milo ( Sorghum vulgare Pers.) shoot to respond to Pfr in subsequent darkness. Two groups of enzymes were studied. In group I (NADP-dependent glyceraldehyde-3-phosphate dehydrogenase, NADP-GPD. EC 1.2.1.13 and ribulose-bisphosphate carboxylase, carboxylase, EC 4.1.1.39) enzyme formation is strongly enhanced by red light pulses (operating through phytochrome) whereas in group II (NAD-dependent glyceraldehyde-3-phosphate dehydrogenase, NAD-GPD, EC 1.2.1.12 and NAD-dependent malate dehydrogenase, MDH. EC 1.1.1.37) enzyme formation hardly responds to red light pulses.
In group 1 a 24-h treatment with blue light (but not with red light) leads to a strong increase in responsivity to Pfr whereas in group II a 24-h treatment with blue or red light does not increase responsivity to Pfr in subsequent darkness.
The specific effect of blue light cannot be explained by an effect of light on gross protein synthesis. Rather, the data indicate that amplification of responsivity to Pfr by blue light is a specific process directly related to the mechanism of modulation of gene expression by phytochrome.  相似文献   

13.
Susan Lurie 《Planta》1978,140(3):245-249
The effect of broad band green, blue and red light on stomatal opening of Vicia faba L. (broad bean) leaves was examined. In air, blue light caused greater stomatal opening than red light. In air with green light stomata were only slightly opened. In a nitrogen atmosphere red light caused greater opening than blue light, and green light caused only slight opening. Opening in air or nitrogen atmosphere in red or blue light was inhibited by the uncoupler CCCP, while the photosynthetic inhibitor DCMU inhibited opening in air but not in nitrogen atmosphere. We concluded that more than one light activated metabolic pathway can supply the energy needed to effect stomatal opening and that different pathways are operative under different conditions.  相似文献   

14.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

15.
Cholecystokinin (CCK), a hormone affecting several gastrointestinal functions, has also been shown to elicit satiety and affect daily meal patterns. Since Zucker obese rats are less sensitive to the satiety effects of CCK, two experiments were designed to determine if they are also less sensitive to the gastric emptying and intestinal transit rate effects of CCK. In the first experiment phenol red was administered to 5.5 hr fasted rats 15 minutes after intraperitoneal injection of CCK-8 or saline. Rats were sacrificed after 30 minutes, the stomach and small intestine were removed, and phenol red content was measured. More phenol red was in the stomach of obese but not lean rats treated with CCK-8. The rate of transit of the contents of the small intestine was increased by CCK-8 and the percent of phenol red in the fourth quarter of the small intestine was greater in obese than lean rats (91 vs 37%, p<0.05). In the second experiment gastrointestinal transit of ferric oxide was measured during the light and dark phases of the diurnal cycle, and when obese rats were ad lib or yoke-fed to lean pair-mates. Total gastrointestinal transit time of the ferric oxide was decreased 15% when CCK-8 was administered to yoke-fed obese rats in either the light or dark portions of the diurnal cycle but was not affected in ad lib-fed obese rats or lean rats. Thus, while Zucker obese rats are less sensitive to satiety effects of CCK, they appear to be more sensitive to the gastrointestinal effects of CCK, and therefore it is not clear what role these gastrointestinal responses have on the feeding behavior responses.  相似文献   

16.
Barley leaf unfolding is stimulated by mixed red and blue light. However, the stimulation from mixed light is attenuated when compared with the stimulation from red light alone, particularly for low intensities of the mixed light and for short irradiation times. For higher light intensity mixtures of red and blue light and for longer irradiation times, the blue light enhances the stimulation from red light and vice versa. This supports the assumption that the blue light effect in this case is also mediated by the phytochrome system. Furthermore the present findings point to the possibility of competitive reactions caused by red and blue light in the excitation of phytochrome.  相似文献   

17.
White, blue, green, red, and deep red illumination were usedto shorten a dark period for plants of Bauhinia monandra under12 hour: 12 hour alternations of white light and darkness. Redalone imitated the effect of white light in advancing the cycleof leaf movement. Deep red did not counteract the effect ofprevious illumination with white light.  相似文献   

18.
The interactions of green or red light with blue light on the dark closing of Albizzia julibrissin Durazz. pinnules have been investigated. Irradiations at 430, 450 and 470 nm progressively delay dark closing with increasing photon fluence rates. Red or green light alone has no effect. However, when the blue fluence rate is low, both red and green light interact with it and increase the delaying effect of the blue light. When the blue fluence rate is high, green light interacts with it to negate some of the effectiveness of the blue light, while red light has no effect. This is similar to results obtained previously with far-red light. It is suggested that the same unidentified photoreceptor is operating in both the far-red and blue regions. The results also indicate the presence of a blue-only absorbing photoreceptor whose action is increased by phytochrome.  相似文献   

19.
Continuous recordings of the effect of light on oat (Avena sativa L. cv. Victory) coleoptile and pea (Pisum sativum L. cv. Alaska) epicotyl growth were made. Using a single excised coleoptile 10 minutes of red light was found to promote growth after a latent period of 46 minutes. The stimulation was transient and was not far red-reversible. Blue and far red light also promoted growth with similar kinetics. The action of continuous red or far red light was similar to that of 10-minute light. The growth of the intact pea third internode (as well as excised segments) was strongly inhibited by red light, with a latent period of 80 minutes. This effect was far red-reversible, and far red and blue light caused only a slight inhibition of growth.  相似文献   

20.
Photooptical response, both of the whole blood and of its non-pigmented fraction-plasma to the low-intensity red light is investigated. For the case of the blood irradiation in vitro it is shown that the mechanism of the low-intensity red light effect on the blood is not directly associated with the pigmented molecular complexes concentrated in erythrocytes. Thus the effect of the low-intensity red light on living organisms includes the mechanisms not using light absorption by the specialized macromolecule--photoreceptor as a primary photophysical action.  相似文献   

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