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1.
目的研究温敏型壳聚糖(chitonsan CS)介入核素188Re内照射对小鼠移植性肝癌(H22)的抑制作用。方法建立小鼠肝癌(H22)模型后随机分成7组,即模型对照组、188Re(0.1mCi)组、188Re-S(0.1mCi)组、188Re+CS(0.1mCi)组、188 Re+CS(0.2mCi)组、188 Re+硫胶体+壳聚糖(188 Re-S+CS 0.1mCi)组和188 Re-S+CS(0.2mCi)组。各组动物瘤内分别注射相应试药,测定肿瘤抑制率。结果 188Re+CS组和188Re-S+CS组肿瘤生长速度减慢,肿瘤生长延迟,肿瘤抑制率在治疗后6 d最高,抑制率分别为67.35%和67.81%。结论温敏型壳聚糖介入核素188Re内照射对小鼠肝癌(H22)具有一定的抑制作用。  相似文献   

2.
In experiments with mature Wistar male rats changes of mediator interrelations in different brain parts, responsible for the central regulation of the hypothalamo-pituitary-adrenocortical system, were detected at early times after whole-body X-irradiation with a dose of 12.9 mC/kg. These changes represent one of the major mechanisms leading, at later times after irradiation, to the development of syndromes related to diencephalic disturbances.  相似文献   

3.
External gamma irradiation of dogs with doses of 103.2 and 51.6 mC/kg combined with the effect of inhaled plutonium-239 accelerates the formation of absorbed doses in secondary organs of the radionuclide deposition by 41.7 and 2.4 times, respectively, whereas the dose of 25.8 mC/kg is ineffective. As estimated by the rate of 239Pu accumulation and by the life span shortening, the minimum effective and the maximum ineffective doses are 104.8 and 80.5 cGy and 89.2 and 79.2 cGy, respectively.  相似文献   

4.
The effect of the addition of radiosensitizers to low-dose total-body irradiation was studied. SR2508 (1 g/kg) or misonidazole (0.35 g/kg) was given 30 min prior to single-dose total-body irradiation, delivered at 0.1 Gy/min. Six dogs received either SR2508 or misonidazole and 2 Gy irradiation, and 14 dogs served as controls, receiving no drug and either 2 or 3 Gy of total-body irradiation. All dogs had a decline in their white blood cell and platelet counts and were supported with prophylactic antibiotics and platelet transfusions. High plasma levels of both radiosensitizers were achieved. The degree of cytopenia with 2 Gy total-body irradiation when combined with either radiosensitizer was not significantly greater than that seen with 2 Gy alone, and the neutropenia was significantly less than that seen with 3 Gy alone. The only observed toxicity of the drugs was vomiting, which started shortly after the infusion of SR2508 and before the radiation treatment. A single high-dose infusion of a radiosensitizer combined with total-body irradiation appears to cause a mild increase in bone marrow toxicity but is otherwise well tolerated.  相似文献   

5.
Combined effect of 460-MHz microwave irradiation and increased (up to 40 degrees C) temperature on Drosophila embryos of definite age was studied. It was demonstrated that the effect of 5-min exposures to non-modulated microwaves with 6 W/kg SAR accompanied with heating is only a little stronger than at normal temperature (24.5 degrees C). Irradiation with pulse-modulated microwaves with pulse repetition rates of 6, 10, 16, and 22 p.p.s. with average SAR of 0.12 W/kg (pulsed SAR 3 W/kg) combined with increased temperature caused some changes in PID dependent on the pulse rate. At 6 and 22 p.p.s, the increase in PID was close to that observed at normal temperature while at 10 and 16 p.p.s. the microwave irradiation did not produce any noticeable effect on development of the Drosophilas.  相似文献   

6.
Interleukin 1 has been shown to provide protection against the toxic effects of cyclophosphamide given in combination with localized irradiation of the lung. A single dose of 15 micrograms/kg interleukin 1 was given 24 h before cyclophosphamide (25-125 mg/kg) which was followed 1 day later by five daily exposures of 4.5 or 5.0 Gy, localized to the lung. Interleukin 1 significantly reduced early measurements of breathing rate for mice treated with high cyclophosphamide doses and irradiation, and at cyclophosphamide doses above 50 mg/kg, there was a significant reduction in the lethality from the combined treatment. At lower levels of cyclophosphamide, however, there seemed to be no effect.  相似文献   

7.
The experiments were carried out on white mice whose brain was irradiated transcranially with laser light in infrared range. Exposure to irradiation was 20 min. In one group of animals only laser light was used, in others laser was combined with morphine (3mg/kg), clonidine (0.5 mg/kg), and diazepam (1 mg/kg) injected intraperitoneally. The nociceptive reactions were studied with the help of "tail-flick" and "hot-plate" tests. It was found that laser light did not modify significantly the results of both tests. Moreover, it didn't influence the antinociceptive properties of morphine, clonidine and diazepam in the "hot-plate" test. In the "tail-flick" test laser light did not affect the action of clonidine, but provided naloxone-independent antinociceptive reaction with diazepam and increased the antinociceptive effect of morphine. Laser irradiation of the brain did not cause any significant morphological changes. These results suggest the possibility of modulating antinociceptive actions of morphine and diazepam by laser irradiation of the brain.  相似文献   

8.
The intraperitoneal injection of analgin (1000 mg/kg), antipurine (400 mg/kg), amidopyrine (100 mg/kg) 3 hours before the irradiation of mice in a dose of 800 R led to survival of 30 to 45% of the animals (against 12.5% in control) and to increase in the average duration of life of the animals that perished. 80-95% of mice survived the period of "intestinal deaths" (the 7th day after the irradiation) after combined prophylactic use of purasolone derivatives and cystamine before the irradiation of these animals in a dose of 1050 R. The radioprotective effect of pyrasolone derivatives given in therapeutic doses was less pronounced.  相似文献   

9.
External gamma-irradiation (7.74 and 15.48 x 10(-2) C/kg) does not influence the distribution of deuterium oxide within a rat body: it is distributed uniformly among the organs and tissues as it is observed in nonirradiated animals. The effect of external irradiation favors the retention of deuterium oxide within the organs and tissues. The delayed excretion of deuterium oxide from the body can enhance the biological effect. This should be taken into account in standardizing the combined radiation effects.  相似文献   

10.
In an early phase II trial combining gemcitabine (dFdC) and radiotherapy for lung carcinomas, severe pulmonary toxicity was observed. In this framework, the objective of this study was to investigate the effect of dFdC on the tolerance of the lungs of C3H mice to single-dose irradiation. The thoraxes of C3H mice were irradiated with a graded single dose of 8 MV photons; dFdC (150 mg/kg) or saline (control animals) was administered i.p. 3 or 48 h prior to irradiation. Lung tolerance was assessed by the LD50 at 7-180 days after irradiation. For irradiation alone, the LD50 reached 14.45 Gy (95% CI 13.33-15.66 Gy). With a 3-h interval between administration of dFdC and irradiation, the LD50 reached 13.29 (95% CI 12.26-14.44 Gy); the corresponding value with a 48-h interval reached 13.01 Gy (95% CI 11.92-14.20 Gy). Our data also suggested a possible effect of dFdC on radiation-induced esophageal toxicity. dFdC has a minimal effect on lung tolerance after single-dose irradiation. However, a proper phase I-II trial should be designed before any routine use of combined dFdC and radiotherapy in the thoracic region.  相似文献   

11.
We examined pain-related behavioral reactions and non-pain behavioral manifestations in mice under conditions of the formalin test. Levels of analgesia induced by i.p. injections of analgin, microwave irradiation of an antinociceptive acupuncture point (AP), E-36, or combined application of the above factors were measured. The duration of the pain behavioral reaction (licking of the injured limb) decreased due to irradiation of the AP with microwaves and to injection of 8.3 mg/kg analgin by 24.3% and 53.8%, on average, respectively. Combination of injection of analgin in a smaller dose (4.2 mg/kg) and microwave irradiation of the AP suppressed manifestations of the pain behavioral reaction by 43.4%. Thus, combination of pharmacologically induced analgesia with the action of microwaves on the antinociceptive AP allows one to significantly decrease the doses of analgesic preparations necessary to provide a full-level analgesic effect; in such a way, side effects of the respective drugs can be weakened. Neirofiziologiya/Neurophysiology, Vol. 38, No. 1, pp. 46–51, January–February, 2006.  相似文献   

12.
Secretion of prostaglandins (Pg) E and F2 alpha in bile in basic condition (without stimulation) and under stimulation with cholecystokinin (CCK) ("Boots", England, 1 unit/kg) in patients with fatty liver with normal (15) and hypokinetic (20) function of gallbladder by radioimmunoassay method was investigated. The mediator role of Pg F2 alpha in the realization of effect of CCK on the contractile function of gallbladder was found. It was concluded, that the disturbance of mediator effect of Pg F2 alpha in the hormone regulation of bile excretion may play an important role in the pathogenesis of biliary dyskinesia. This disturbance of mediator effect of Pg was connected with the reducing of concentration and debit Pg F2 alpha in bile, as well as with the slowing of maximal Pg excretion under stimulation with CCK.  相似文献   

13.
The acute effects after administration of 3-O-Methyl-D-Chiro-inositol, D-Chiro-inositol and manganese, components of the pH 2.0 putative mediator of insulin action, on plasma glucose were examined in low dose streptozotocin-treated rats. 3-O-Methyl-D-Chiro-inositol at a bolus dose of 5 mg/kg decreased plasma glucose 6% at 120 min (p < 0.05). A higher bolus dose of 3-O-Methyl-D-Chiro-inositol (15 mg/kg) promoted a more persistent hypoglycemic effect of 22% at 120 min (p < 0.05). Infusion of 8.3 microg/min of manganese chloride lowered plasma glucose by 23% (p < 0.05). 3-O-Methyl-D-Chiro-inositol (15 mg/kg) together with manganese chloride (8.3 microg/min) promoted a reduction of 49% in 120 min (p < 0.05). D-Chiro-inositol at a bolus dose of 5 mg/kg had no effect. A single dose of 15 mg/kg produced a reduction of 21% (p < 0.05) in 120 min. D-Chiro-inositol (15 mg/kg) associated with manganese chloride (8.3 microg/min) decreased elevated plasma glucose 47% (p < 0.05) in 120 min. D-Chiro-inositol coadministered with manganese reduced glucose concentrations during the final 60 min (p < 0.05). 3-O-Methyl-D-Chiro-inositol and D-chiro-inositol are components of the mediator structure. Manganese is also a presumed component of the mediator, having an important role in glucose uptake, insulin release and mediator generation. These compounds have also been identified in the literature as hypoglycemic agents.  相似文献   

14.
In studying the combined effect of single and fractionated exposure to gamma/neutron radiation (12.5-50 cGy) and sodium nitrite (100 mg/kg) and chronic irradiation with a mixture of radiation (25 cGy) and sodium nitrite, nitrate (10-100 mg/l) the synergistic effect was observed in inducing reciprocal translocations in mouse spermatocytes. The dose-response function of the reciprocal translocations occurrence in Af mouse spermatocytes was nonlinear; there was a "plateau" within the dose range from 25 to 50 cGy.  相似文献   

15.
The influence of X-radiation on activity of lysosomal enzymes (D, L, H cathepsins) in rat spleen tissue and in inoculated rat sarcoma 45 has been investigated. Intact rats and rats with tumors were subjected to whole-body and sarcoma 45 to local irradiation with doses of 0.155 C/kg and 0.31 C/kg in conditions of breathing gas hypoxic mixture containing 90% of nitrogen and 10% of oxygen (GHM-10). The combined exposure to radiation and GHM-10 was shown to produce a certain protective action (e.g. normalized cathepsin activity) in the spleen. In the tumor tissue the protective effect of GHM-10 was absent.  相似文献   

16.
It was shown that a single injection of heparin (250 units/kg) 15 min and 24 h before irradiation potentiated a slight radioprotective effect of cystamine (dichlorohydrate, 170 mg/kg) which was registered after the administration thereof to mice 30 min before irradiation with an absolutely lethal dose at a dose rate of 0.0025 Gy/c.  相似文献   

17.
In experiments on Wistar rats a study was made of the carcinogenic effects of the combined exposure to 241Am administered intraperitoneally (6.7 to 229.4 kBq/kg body weight) and external gamma-radiation (137Cs, 175 cGy). The occurrence of osteosarcoma, leucosis, skin and mammary tumors increased in the exposed animals. The combined irradiation produced an additive carcinogenic effect.  相似文献   

18.
The dynamics of chromosomal aberrations in seedling root merysteme is explored in various terms of irradiation of two genotype corn dry seeds. The effects of chronic irradiation with low rate dose, with acute and with combined irradiation are explored in the different terms of seed storage. It is shown that the output of chromosomal aberrations and of the efficiency of irradiation (1/Gy) change depending on the accumulated dose of chronic irradiation and for both genotypes are described by unmonotonous functions. Efficiency of acute irradiation changes the dependence on the terms of seed storage. The efficiency of chronic irradiation considerably exceeds the efficiency of acute irradiation. Antagonistic effect of combined irradiation dry seeds of one of genotypes is marked.  相似文献   

19.
A study was made of the effect of different radiation doses on the brain enzymes degrading enkephalins. Enkephalin aminopeptidase activity decreased during the first 60 min following irradiation with a dose of 774 X 10(-4) C/kg and increased after a dose of 3096 X X 10(-4) C/kg; enkephalinase A exhibited opposite changes. 48 hr after irradiation, enkephalin aminopeptidase activity exceeded the normal level, and no significant changes occurred in encephaliase A activity irrespective of the radiation dose.  相似文献   

20.
The mandibular condyles of eight growing male monkeys (Macaca fascicularis) were analyzed by using a combination of radioautographic and morphometric techniques. This was done with the aim of examining the dynamics in the structure and growth activities of the articular tissue covering as well as of the subchondral zone of erosion. The animals received 1 mCi/kg body weight 3H-proline 24 hr and 0.5 mCi/kg body weight 3H-thymidine 3 hr prior to death. Their age was estimated on the basis of skeletal maturation as recorded from radiographs of the hand and wrist. Consistently, the proliferative activity in the intermediate layer, the rates of cell turnover and growth of chondroblasts and chondrocytes, the rates of extracellular matrix production in the intermediate and chondral layers, as well as the resorptive and appositional activities in the zone of erosion were characterized by an in-concert behavior. This behavior suggests a general synergistic control of the various cell dynamic and metabolic processes affecting the rate of normal condylar growth.  相似文献   

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