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621.
Responses of mycelia ofGanoderma lucidum to vanadium, selenium and germanium were examined over a wide range of concentrations (10–1, 120 μg/ml) in pure culture.
Se and V were found to be highly toxic, but Ge was not toxic at the levels tested.Ganododerma lucidum cultivated on substrates of sawdust with V (30–80 μg/g) developed mature fruitbodies, but the bioaccumulation of V was quite
low (2.5–7 μg/g in pileus, 12.5–21.5 μg/g in stipe and <1 μg/g in basidiospores). Se as Na2SeO4 labeled with75Se was effectively taken up from substrates and accumulated in fruitbodies (mainly in pileus), then depleted by discharge
of basidiospores. Ge as GeCl4 labeled with77Ge was easily uptaken and translocated into fruitbodies. 相似文献
622.
Simple corrected density indices (CDIs) have been used to measure reductions in pest density in fields. In the contemporary pesticide registration system, few comprehensive statistical frameworks are available that can integrate multiple datasets to evaluate how pesticidal effects are influenced by the products' properties such as mixing multiple active ingredients and possession of systemic ability. In this study, we provide a statistical framework for evaluating pesticide efficacy from multiple field trials and applying it to contemporary pesticides. In this framework, we extended the conventional CDI to a generalized linear mixed model (GLMM), which we applied to a dataset of the pesticide registration test in Japan (n = 758). The estimated mortality of a single active ingredient in reducing pest density is 88.0%, indicating the registered pesticide satisfies the “effective” criterion (roughly 70–95%) under the current pesticide registration system in Japan. Although systemic ability additionally reduced pest population to 55.5% of the post-treatment densities, the addition of active ingredients scarcely enhances efficacy (reducing population to 74.6%), suggesting that the pesticide design resulted in broadening the spectrum of target species rather than increasing toxicity. 相似文献
623.
Tetsuya Tsuji Shinji Takeoka Yosuke Okamura Ryo Sudo Yasuo Ikeda Kazuo Tanishita 《Journal of Biorheology》2009,23(1):29-34
Polymerized albumin particles (poly Alb) with recombinant glycoprotein Ibα (rGPIbα-poly Alb) are a promising candidate for
a platelet substitute. Thus, we focused on the lateral motion of poly Alb in the presence of red blood cells, because the
lateral motion plays an important role in aggregate formation. We visualized the microscopic motion of poly Alb toward the
immobilized ligand (von Willebrand factor, VWF) surface in a model arteriole with red blood cells with a high-speed camera.
At a higher shear rate of 1,500 s−1, the concentration profile of poly Alb appeared to peak near the wall. This profile enhances the interaction between the
particles and wall. Particularly the migration angle, being the angle of the poly Alb velocity vector, was enlarged near the
wall and contributed to transfer of poly Alb toward the immobilized VWF surface. This tendency is desirable to achieve the
adhesion of particles on the wall. 相似文献
624.
625.
Lipid droplets appeared during the growing phase in the culture medium of incompletely transformed rat fibroblasts (HY1) induced by AccI-H fragments of adenovirus 12 DNA. These droplets consisted of neutral lipids, DNA, histones and RNA. Electron microscopic observations showed that the droplets had no lipid-bilayers on their surfaces which accounted for the tendency of the droplets to readily fuse together and become larger, and that the inner structures of the droplets looked like networks of fibrous matter. Experiments with DNA hybridization showed that the droplet DNA was composed of both cellular and adenoviral DNA, and that the cellular DNA in the droplets seemed to be derived from various cell DNA sequences. These results suggest that the droplets were derived from parts of the nuclear components of HY1 cells. The mechanisms for droplet release are discussed. 相似文献
626.
627.
Studies of the halothane-cooling contractures of skeletal muscle 总被引:1,自引:0,他引:1
R T Sudo G Zapata G Suarez-Kurtz 《Canadian journal of physiology and pharmacology》1987,65(4):697-703
The characteristics of transient contractures elicited by rapid cooling of frog or mouse muscles perfused in vitro with solutions equilibrated with 0.5-2.0% halothane are reviewed. The data indicate that these halothane-cooling contractures are dose dependent and reproducible, and their amplitude is larger in muscles containing predominantly slow-twitch type fibers, such as the mouse soleus, than in muscles in which fast-twitch fibers predominate, such as the mouse extensor digitorum longus. The halothane-cooling contractures are potentiated in muscles exposed to succinylcholine. The effects of Ca2+-free solutions, of the local anesthetics procaine, procainamide, and lidocaine, and of the muscle relaxant dantrolene on the halothane-cooling contractures are consistent with the proposal that the halothane-cooling contractures result from synergistic effects of halothane and low temperature on Ca sequestration by the sarcoplasmic reticulum. Preliminary results from skinned rabbit muscle fibers support this proposal. The halothane concentrations required for the halothane-cooling contractures of isolated frog or mouse muscles are comparable with those observed in serum of patients during general anesthesia. Accordingly, fascicles dissected from muscle biopsies of patients under halothane anesthesia for programmed surgery develop large contractures when rapidly cooled. The amplitude of these halothane-cooling contractures declined with the time of perfusion of the muscle fascicles in vitro with halothane-free physiological solutions. It is suggested that the halothane-cooling contractures could be used as a simple experimental model for the investigation of the effects of halothane on Ca homeostasis and contractility in skeletal muscle and for study of drugs of potential use in the management of the contractures associated with the halothane-induced malignant hyperthermia syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
628.