1984年 · 第04卷第01期

The inhibitory effect of sodium alginate (extracted from sargassum siliquastrum) on the absorption of stable strontium marker in human gastrointestinal tract was investigated.

The observations were scheduled into experimental and control periods. The inorganic salt contents in the diet were strictly controlled and balanced during these periods. Fourteen normal healthy adult volunteers (9 males and 5 females) were included and divided into two groups. In group I, after administration of 5mg of stable strontium, 12~15g sodium alginate in solution was immediately given to 9 subjects (6 males and 3 females); in group II, 20 minutes prior to oral administration of 5mg of stable strontium, 200~250g biscuit containing 12~15g of sodium alginate was given to 5 subjects (3 males and 2 females). The serum concentration and urinary excretion (24 hours) of Sr, Ca, Fe, Cu and Zn both in the experimental and control periods were measured by proton induced X-ray emission (PIXE) technique. The results obtained were compared in pairs and in groups. It was found that the stable strontium concentration (content) both in serum and in urinary excretion (24 hours) was reduced 73 ± 8.9% and 78 ± 11% respectively by the sodium alginate extracted from sargassum siliquastrum. Sodium alginate in the amounts given above does not influence the absorption of Ca, Fe, Cu and Zn.

This report summed up the results of histopathological changes of thyroid glands in 27 dead and killed dogs 7~69 months after ingestion of early fallout or fission products. The absorbed dose of thyroid was 2.89~1.7×10⁵ rads. Histopathological appearances of various thyroid glands could be approximately divided into five types: (1) no apparent change; (2) follicular degeneration with extensive stromal fibrosis; (3) follicular atrophy; (4) disappearance of follicles with fibrosis and hyaline change; (5) necrosis and calcification. Within the dose range of 2.7×10³ to 1.0×10⁵ rads, the thyroid damage increased with the increase of the absorbed dose; with the dose below 1.2×10³ rads, no histopathological changes were seen. Above 1.0 x 10⁵ rads, the histopathological changes were not increased apparently. Therefore, 2.7 x 10³ rads may be considered as the minimum dose to induce thyroid changes, while the dose causing serious destruction of thyroid may be above 1.0 x 10⁵ rads.

Two hundred and thirty male rats were irradiated with 2.5 to 2100 Gy of ⁶⁰Co gamma rays. Radiation dose below 1500Gy caused acute radiation sickness, and that above 1500 Gy led to immediate radiation death.

Acute radiation sickness in rats may also be classified under haematopoietic, gastrointestinal and cerebral types. The upper limit of dose causing haematopoietic death in rats was 9.5 (8.5~10) Gy, gastrointestinal death 200~250 Gy and cerebral death approximately below 1500 Gy. The characteristics of gastrointestinal and cerebral death in rats are discussed.

In this experiment 18 mongrel male adult dogs were used. The animals were divided into 3 groups and received 1580, 1330 and 956 rads of neutron and γ-rays, respectively. Following exposure they manifested frequent vomiting, severe bloody diarrhea and hemopoietic depression. All of them died 2.8~4.8 days after irradiation. The causes of death are discussed.

Our experiences with 20 cases of local cutaneous radiation ulcers repaired with skin flaps are as follows: (1) the area excised should be larger than that of ulcer in order to remove all necrotic and degenerative tissues; (2) the depth of excision was usually based on the conservative technique of "biological excision"; (3) different types of skin flaps for surgical repair of excised ulcer might be selected according to necessity; (4) the skin flaps had a high resistance to infection; (5) the flapping could improve blood supply and nutrition of local tissue and relieve pain. The different characteristics of 4 types of skin flaps for repairing this kind of injury are discussed. It is suggested that the local flap and myocutaneous flap might have better effect than the others.

Adult Wistar rats of 180~200 grams were used in this study. The rats were irradiated with varying doses (100~600rads) of ⁶⁰Co γ-rays or subjected to second degree burns in 15% of body surface, or sustained combined injury by the two above agents. Micronuclei in peripheral blood lymphocytes were counted after 12 hours.

The results showed that micronucleated cell frequency and micronucleus frequency were all very similar between the control and the burned rats, and between the irradiated and the combinedly injured rats. The differences were not significant. The patterns of the curves obtained from analysis of regression were the same, and the differences between the regression equation of the same indicator were not significant.

It is considered that second degree burns in 15% of body surface had no effect on micronucleus frequency in peripheral blood lymphocytes of rats, and that the latter can still be used as an assistant indicator for dose evaluation of combined injury of radiation and burn at early stage.

It is known that microcirculation in irradiated animals changes obviously, and the improvement of microcirculation would conduce to the recovery of radiation injury. This paper reports the therapeutic effect of the traditional Chinese medicine Qi Jia Dan (芪甲丹) injection on the disturbance of pinna and marrow microcirculation in mice irradiated with 600 rads of γ-rays. It was shown that the injection was effective in improving microcirculation. The calibre of microvessels in treated mice was smaller than that in controls. Transudation and bleeding were relieved, and blood flow was faster, and the function of microcirculation was more steady in injected mice. The microcirculation of marrow after exposure was more heavily damaged than that of pinna. The injection, however, could promote the microcirculation in marrow, but was not so effective in pinna. In conclusion, Qi Jia Dan has the effect of replenishing vital energy and removing stasis. It is effective against microcirculatory disturbance in irradiated animals, and can be used for early treatment of radiation sickness.