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The human placental alkaline phosphatase (PLAP) gene was analysed for its utility as a histochemically detectable reporter gene in transgenic mice. A reporter gene was made by linking the PLAP structural gene to an enhancer-promoter element from the human beta-actin gene. This gene was inserted into the mouse genome by transfection of embryonic stem cells, and by microinjection of fertilized eggs. Histochemical staining showed that the transgene was uniformly expressed in four of four stable ES cell lines, and in all ten tissues examined from adult animals from five lines of transgenic mice. Non-transgenic cells did not stain. These results suggest that the human PLAP gene will be of utility in studies requiring phenotypic marking of cells in tissues of mice. 相似文献
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RW Mann ME Feather CS Tumosa TD Holland KN Schneider 《Canadian Metallurgical Quarterly》1998,97(2-3):79-86
We review and present current evidence supporting independent regulation of nuclear Ca2+ ([Ca2+]n). The nucleus and nuclear envelope contain proteins to both regulate and respond to changes in [Ca2+]n. However, this does not prove that [Ca2+]n is independently regulated from cytosolic Ca2+ ([Ca2+]c). Studies using fluorescent dyes suggested that changes in [Ca2+]n differed in magnitude from changes in [Ca2+]c. These studies have been criticised as the nuclear environment alters the fluorescent characteristics of these dyes. We have evaluated this question with aequorin targeted to the nucleus and cytoplasm and shown that the characteristics of the indicators are not altered in their respective environments. We have demonstrated that different stimuli induce changes in [Ca2+]n and [Ca2+]c that vary both temporally and in magnitude. The nucleus appeared to be shielded from increases in [Ca2+]c, either through a mechanism involving the nuclear envelope or by cytosolic buffering of localised increases in Ca2+. In addition, agonist stimulation resulted in an increase in [Ca2+]n, consistent with release from the perinuclear Ca2+ store. There was a stimulus dependence of the relation between [Ca2+]n and [Ca2+]c suggesting differential regulation of [Ca2+]n. These results have important implications for the role of Ca2+ as a specific regulator of nuclear events through Ca2+ binding proteins. In addition, they highlight the advantages of using targeted aequorin in intact cells to monitor changes in organelle [Ca2+]. 相似文献
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The authors report their clinical observations of 44 patients, aged from 2 months to 14 years, with acute pulmonary abscesses. As evidenced by the authors a roentgenological examination in dynamics is of great value in establishing the diagnosis of pulmonary abscess, since it makes possible to follow the destruction of lung tissues and the formation of cavities. For treatment of lung abscesses different methods were employed: toilet bronchoscopy with antibiotics perfusion, puncture and drainage of the abscess, in case of pulmonary hemorrhage a resection of the lung portion involved, the complex conservative therapy. 相似文献
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1. Rates and rate coefficients of glucose utilization and replacement in post-absorptive rats, either conscious or under halothane anaesthesia, were determined in a thermoneutral environment by using [5-3H]- and [U-14C]glucose. Label was not injected into rats under halothane until about 0.5h after anaesthesia was initiated. 2. Comparison with the results for 24h-starved rats in the preceding paper [Heath et al. (1977) Biochem. J. 162, 643-651] showed that insulin concentrations were considerably higher but rate coefficients for glucose utilization were little altered in post-absorptive rats. Sensitivity to insulin was thus considerably increased by a 24h period of starvation in the rat. 3. Fractional recycling of glucose carbon in post-absorptive rats was under one-half of that in starved rats, reflecting the larger contribution of liver glycogenolysis to glucose production in the former. 4. In post-absorptive rats halothane decreased the mean rate of glucose utilization by about 17%. This decrease was associated with an increase in mean plasma insulin concentration, showing that halothane decreased sensitivity to insulin. 5. Recycling was slightly increased by halothane, indicating that the contribution of liver glycogen to the total glucogenic rate was decreased, probably because liver glycogen concentration were about 40% lower throughout the rate determinations in halothane. 6. Comparison of our results with earlier work shows that during and shortly after induction of halothane anaesthesia glucose turnover must have been greatly increased whereas from about 0.5h after induction it was decreased. 相似文献
78.
This study examined the effects of client and therapist sex on client self-disclosure and improvement from individual psychotherapy. Based upon closing summary data collected at a college psychological counseling center, it was found that clients were more likely to be rated as low disclosers by female than by male therapists. Males viewed more clients as improved than did females (74% vs. 50%). 相似文献
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