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141.
Local interferon injection in four patients with cervical intraepithelial neoplasia (CIN) regularly elicited progressive regression of the lesions. The response was observed with exfoliative cytology after each injection, guided by colposcopic examination. The cytologic changes showed a cytocidal effect mainly on the dyskaryotic cells, preceded by cellular degeneration not unlike that of nonspecific inflammation and accompanied by an increase in neutrophil infiltration. The cytologic response was closely correlated with partial or complete clinical regression based on the absence of viable or degenerated dyskaryotic cells in the cervical smears. Three patients showed complete clinical regression after treatment. One patient showed recurrent viable dyskaryotic cells when the dosage was reduced, and treatment was suspended temporarily although her lesion had regressed completely after five injections. Clinical recurrence was noted one week after viable dyskaryotic cells reappeared in her smears. These observations suggest that cytology may be a useful means of monitoring interferon treatment in CIN.  相似文献   
142.
C E Tan  J A Ballweg 《Social biology》1984,31(3-4):232-242
Desired family size and contraceptive behavior of 986 ever-married women aged 15-54 from Northern Mindanao, the Philippines, are described. Using the Dow and Werner typology of demographic and contraceptive patterns, it was found that a majority of the women were traditional in their demographic attitude and contraceptive behavior. A substantial proportion of the women desired medium to large families. In consistency in attitude and behavior was also manifested by women who desired small families but have never used efficient family planning methods. Sociodemographic characteristics of these women are described. A majority of the women who have never used efficient contraception also never practiced family planning. Rhythm was the primary method of birth control among demographic innovators and traditionals who have ever used inefficient methods; the pill was popular among contraceptive innovators and moderns. A considerable proportion of the demographic innovators and the traditionals were not currently using any family planning method; a lesser proportion of contraceptive innovators and moderns were also not using birth control methods. Relevance of the findings to family planning programs is pointed out. Recommendations are given. Motivation for a small family is a prerequisite for a successful family planning program. Without motivation, what family planning programs do is reduce the number of unwanted births. Family planning programs should reach out to those who are sufficiently motivated to have small families but have never used efficient family planning methods. A major finding of this research is that a majority of the women who never used efficient contraception also never used inefficient or traditional methods. Efforts should be made to change this. Additionally, efforts should be made to bring those modern and contraceptive innovators who had stopped using any family planning method to practice contraception again.  相似文献   
143.
Yeoh  H. H.  Tan  T. K.  Tian  K. E. 《Mycopathologia》1984,87(1-2):51-55
Species of Cunninghamella, Gliocladium deliquescens, Trichoderma harzianum and T. koningii were isolated from rotten wood chips. When grown on medium containing cellulose, all except Cunninghamella produced the three primary enzymes (exoglucanase, endoglucanase and -glucosidase) of the cellulase complex. The patterns for enzyme production, changes in mycelial mass and pH of the induction medium for T. harzianum and T. koningii were closely similar, and were distinguishable from those of G. deliquescens.  相似文献   
144.
Uptake of d-glucosamine by rat brain synaptosomes occurs via a saturable transport process (Km 2.1 mM, V 3.0 nmol/mg per min) which was clearly distinguishable from simple diffusion. This transport process is highly sensitive to cytochalasin (Ki = 7 · 10?5 mM. d-Glucose competitively inhibits d-glucosamine uptake with a Ki value of 8 · 10?1 mM.  相似文献   
145.
C.H. Tan  J. Robinson 《Life sciences》1982,30(14):1205-1210
The effect of 2-bromopalmitate, an inhibitor of fatty acid oxidation, on progesterone synthesis in isolated luteal cells was studied. Incubation of the cells with increasing concentrations (0 – 2 mM) of the inhibitor resulted in an initial enhancement of progesterone synthesis, both in the presence and absence of LH (1 μg/m1). In the LH-treated cells, this stimulation in steroid synthesis becomes markedly impaired at 2 mM 2-bromopalmitate. In the control cells, however, progesterone synthesis was sustained at the elevated level. At high concentrations of 2-bromopalmitate, the stimulatory effect of LH (relative to the controls) on steroidogenesis was progressively diminished, until it was completely abolished at an inhibitor concentration of 2 mM. The oxidation of labelled palmitic acid by luteal cells was also effectively inhibited by 2-bromopalmitate (1 mM). The results indicate that the steroidogenic effect of LH is mediated, in part, by fatty acid oxidation, and were explained in terms of the interaction between carbohydrate and fatty acid oxidation in supporting ovarian steroidogenesis.  相似文献   
146.
Effect of Carbon Dioxide on Growth of Meat Spoilage Bacteria   总被引:8,自引:1,他引:7       下载免费PDF全文
The ability of CO2 to inhibit respiration and growth of representative strains of seven species of meat spoilage bacteria was examined. Enterobacter and Microbacterium thermosphactum were unaffected by CO2. Both respiration and growth of the other species were inhibited. With four of the species (fluorescent and nonfluorescent Pseudomonas, Alteromonas putrefaciens, and Yersinia enterocolitica), the inhibition pattern in a complex medium was similar, and inhibition was incomplete and reached a maximum level at comparatively low concentrations of CO2. With Acinetobacter, inhibition continued to increase with increasing CO2 concentration. The degree of inhibition with a constant concentration of CO2 in solution increased with decreasing temperature for all CO2-susceptible species except the nonfluorescent Pseudomonas. Anaerobic growth of CO2-susceptible facultative anaerobes was unaffected by CO2.  相似文献   
147.
When flax seedlings are decapitated above cotyledons and three days later one of the two cotyledons is removed then the remaining cotyledon stimulates in four to five days growth of its axillary bud. It has been found that content of endogenous cytokinins was higher in the stimulated bud as compared with the other one already 12 h after the cotyledon removal. Flax seedlings decapitated under cotyledons regenerate adventitious buds on thy hypocotyl stump during 5–6 days. The endogenous fytohormonal preparation of this regeneration was investigated in the 20 mm apical part of the hypocotyl stump. Decrease in auxin and increase in gibberellins was already found during the first day after decapitation while the level of cytokinins increased as late as three days after the apex removal.  相似文献   
148.
[3H]Mepyramine binds with high affinity to membranes from brain of human, rat, guinea-pig, rabbit and mouse with drug specificity indicating an association with histamine H1receptors. Considerable species differences occur in the affinity of [3H]mepyramine, with guinea-pig and human having 34 times greater affinity than rat, mouse or rabbit. The greater affinity of [3H]mepyramine in guinea-pig than in rat is attributable both to faster association and slower dissociation rates in guinea-pig. Species differences in affinity for H1 receptor sites occur for some antihistamines but not for others. Some tricyclic antidepressant and neuroleptic drugs are extremely potent inhibitors of [3H]mepyramine binding, exceeding in potency any H1 antihistamines examined. The tricyclic antidepressant doxepin and the neuroleptic clozapine are the most potent of all drugs examined in competing for [3H]mepyramine binding. The regional distribution of specific [3H]mepyramine binding differs considerably in the various species examined.  相似文献   
149.
The effect of EMG biofeedback-assisted relaxation on blood pressure and selected biochemical parameters was evaluated in 38 patients with essential hypertension. Training consisted of 8 weeks of biofeedback and home practice of relaxation exercises. Mean blood pressure decreased in the experimental group from 144/90 to 133/84 mm Hg while the control group remained unchanged. Statistically significant decreases in the experimental group also occurred in muscle tension levels, in plasma aldosterone, and in urinary cortisol. Both aldosterone and cortisol are secreted by the adrenal cortex. It was concluded that the technique taught to the experimental group produced a reduction in skeletal muscle tension and a decrease in stress responding mediated by the adrenal cortex.This work was supported by the Northwestern Ohio Heart Association Grant No. 93298. It was presented as a citation paper at the meetings of the Biofeedback Society in 1979 and 1980.  相似文献   
150.
The properties of seven enzymes were studied in extracts from Myxobacter AL-1. The enzymes were isocitrate dehydrogenase (E.C. 1.1.1.42), succinate dehydrogenase (E.C. 1.3.99.1), alkaline phosphatase (E.C. 3.1.3.1), -glucosidase (E.C. 3.2.1.20), -glucosidase (E.C. 3.2.1.21), -galactosidase (E.C. 3.2.1.23), and N-acetyl-glucosaminidase (E.C. 3.2.1.30). Four of these enzymes: isocitrate dehydrogenase, -glucosidase, -glucosidase, and -galactosidase are cytosolic enzymes. Succinate dehydrogenase was found to be located on the cytoplasmic membrane system, whereas alkaline phosphatase and N-acetyl-glucosaminidase were considered as enzymes which bind the outer membranes resp. the cell wall. During the cell cycle, all enzymes have a pattern of discontinuous activity increase. Succinate dehydrogenase and isocitrate dehydrogenase exhibit a stepwise increase of activity, whereas the other enzymes follow the pattern of a peak enzyme.  相似文献   
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