1987年 · 第100卷第11期

Five living eyeballs of Chinese patients scheduled for exenteration were used to determine the retinal injury threshold for irradiation with pulsed Nd:YAG laser at 150 µs. The injury threshold ED50 was 1.55 mJ, with a confidence limit of 1.30-1.86 mJ. When the laser energy approximated the value causing injury to the retina, the power intensity of the laser reaching the cornea was P=429W/cm2. Experiments on rabbits and rhesus monkeys showed that the retinal injury thresholds of 150 μs pulsed Nd:YAG laser were 0.885 mJ and 0.259 mJ respectively. The ratios of retinal injury thresholds for grey rabbits, rhesus monkeys and yellow people were l.0:3.4:6.0. Obviously, the human eye is more tolerant to laser at l.06 μm wave length than rabbit and monkey eyes.

Rat corpora lutea (CL) were utilized to examine a series of tyrosine analogues for their structure-activity relationships. CL were obtained from immature rats pretreated with pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). The results indicated that hCG stimulated the production of progesterone and this effect was blocked by tyrosine. The effects of 17 analogues were compared with those of hCG and tyrosine in this system. It was shown that the essential functional groups necessary for progesterone antagonism production were the tyrosine α-amino and phenolhydroxyl groups, while the carboxyl group was seemingly essential for the antagonistic effect. Among the tyrosine analogues, tyrosine hydrazide and glycyl-tyrosine were more potent than tyrosine.

We treated 109 girls with isosexual precocious puberty with true precocious puberty in 63 and pseudoprecocious in 46. The true and pseudopreco- cious puberties were classified etiologically and differentiated according to their clinical features. Re suIts of treatment showed that chlormadinone was effective in controlling menstruation and secondary sex characters in 43 patients with true precocious puberty except 2 who were more than 8 years old, and that this agent has no effects on physical development including the final height.

A quantitative analysis of anisodamine-acetyl-choline (Ach) antagonism was obtained using isolated strips of canine tracheal smooth muscle. Schild plots yielded anisodamine-Ach pA2 and pA10 values of 7.48 and 6.49 respectively and a pA difference of 0.99. Atropine-Ach pA2 and pA10 values were 8.8 and 7.9. Thus, anisodamine is a reversible, competitive muscarinic antagonist in canine tracheal smooth muscle. However, anisodamine is considerably less potent than atropine since a 22 to 25-fold higher concentration of anisodamine is required to produce the same degree of muscarinic blockade as atropine.

This study was undertaken to evaluate the effectiveness of an aggressive expectant regime in the management of placenta previa centralis from August 1980 to December 1984. This regime emphasized adequate blood transfusion, use of tocolytic agents, assays for fetal maturity profiles and planned delivery. 32 cases of placenta previa centralis were encountered in this period, of which 19 premature cases fulfilled the criteria for the study. The mean duration of gestational weeks prolonged was 5.11±2.77 weeks. All cases except one were managed by planned delivery after 34 weeks of gestation. One pregnancy was terminated at 31 weeks of gestation by emergency cesarean section because of acute attack of profuse bleeding. The infant suffered from IRDS and died because the family refused energetic treatment after 72 hours of resuscitation. The corrected perinatal mortality rate is zero.

Fifteen hybrid rats divided int0 3 groups (A, B and C) were fed for 250 days with distilled, 50 ppm and 80 ppm NaF water respectively. Before exsanguination, doubled tetracycline labelings were made on all of the experimental animals for bone dynamic study. The available data suggest that the primary mineralization and matrix synthesis in group B and C were significantly inhibited, indicating the toxic effects of high fluoride on osteoblasts. For a better understanding of the pathogenesis of osteosclerosis, osteomalacia and osteoporosis in endemic fluorosis, we would suggest that fluoride be used not only as a stimulator for bone formation as is being recommended in the treatment of postmeno pausal ostcoporosis accompanied somewhat by osteosclerosis, but also as an inhibitor for matrix synthesis and primary mineralization through its toxic effects on osteoblast. We believe that the pathology of fluorosis depends largely on the dose of fluoride intake.

A nation-wide survey on smoking was carried out from April to November 1984, covering all 29 provinces, autonomous regions and municipalities directly under the Central Government (except Taiwan). Stratified random sampling was done in the general population in those aged 15 years and above. A total of 519600 persons were surveyed, including 258 422 males and 261 178 females. It was shown that the average smoking rate of Chinese is 33.88%, with 61.01% males and 7.04 females. The heaviest male smokers are workers and peasants, and the females ones are professionals and workers. The highest educated people have the lowest smoking rate in both sexes. Of 343 563 non-smokers interviewed, 39.75% are passive smokers. The quit smoking rate is only 4.17% in males and 9.73% in females.

Mouse and rat pathological models were produced by injections of thyroid hormone (T3 or T4, Model I) or hydrocortisone (HC, Model II). A single subcutaneous dose of isoproterenol (ISO) caused plasma cAMP to peak in 5-15 min which was significantly higher in mouse Models I and II than in normal mice. Daily oral administration of a decoction of two Yin tonics-Radix Rehmanniae (RR) and Plastrum Testudinis (PT) reduced peak cAMP in both models. 3H-DHA binding assay re vealed significant elevations of the number of β-adrenergic receptors in rat Models I and II. Decoction RR and PT restored the peaks to normal range. Yang tonics Radix Aconiti praeparata (RAP) and Cortex Cinnamomi (CC) showcd contradictory effects on these models. It seems unlikely that the action of the two tonics promotes the clearance of injected hormones, since injected hormone RIA in plasma showed no differences between Yin tonics treated and untreated models. The therapeutic effects of these two Yin tonics on "Yin deficiency" syndrome of hyperthyroidism or hyperfunction of the adrenal cortex is very probably related to their actions on the β-adrenoreceptor-cAMP system as stated.

This study aims to assess the effects of modifying dietary sodium intake among 73 children aged 3 to 5 years from two kindergartens in Beijing. Diet of the experimental group (kindergarten I) was modified toward a goal of 70 mEq sodium per person per day for six months. Kindergarten II was used as control. The sodium intake and blood pressure of the experimental and control groups were com pared before the experiment and six months later. There was a significant decrease in urinary sodium excretion, diastolic blood pressure and mean arterial pressure after six months in the experimental group (p<0.001), while no significant changes were found in diasotlic blood pressure and mean arterial pressure in the control group. Meanwhile, both groups showed significant increase (p<0.001) in height and weight over the six month period.

Ninety-six fluorescein angiograms were performed on 77 patients with retinal vein occlusion (RVO), of whom 40 had branch retinal vein occlusion (BRVO) and 37 central retinal vein occlusion (CRVO). All patients were given both Western and Chinese herbal medicines to stimulate blood circulation and resolve vascular stasis. The time of follow-up ranged from 2 months to 4 years (mean, 11 months). The relationship between visual acuity and the fluorescein angiographic abnormalities such as arterial perfusion, collateral circulation, neovascularization, and macular edema was studied. It is conclude that the factors influencing prognosis are the site and extent of obstruction, the amount of arterial perfusion and the integrity of the perifoveal capillary bed, the development of collateral circulation, and neovascularization.