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51.
Snellius-II sponge collecting yielded 355 species (together about 1300 specimens). An illustrated simplified key to the more common reef forms is presented using only field characters. A preliminary taxonomic review of the Indonesian sponge fauna is given based on an analysis of material collected during the Snellius-II Expedition, of older material of the Siboga Expedition (so far largely unpublished), and of data in the literature (most recent dating from before 1935).The Indonesian sponge fauna, which is provisionally estimated to comprise 830 nominal species (obvious synonyms not counted) is compared to the fauna of relatively well-studied areas elsewhere in the Indo-Pacific region and to the West Indian sponge fauna, using numbers of species of each of 188 genera occurring in more than one of the areas concerned. Based on published reports the Australian tropical sponge fauna appears to be dissimilar to that of Indonesia.  相似文献   
52.
Newcastle Disease Virus (NDV) strain “H” and Polyinosinic-Polycytidylic acid (Poly I:C) were used for interferon (IFN) induction in secondary pig kidney cells. A functional IFN system was detected and characterized. A wide similarity with the correspondent human and bovine systems was appreciated, with particular regard to the kinetics of synthesis. A glycosylated protein was essential for activity in bovine cells, but not in swine cells. Poly I:C proved to be a very weak inducer, even in conditions which promote IFN synthesis in other cell substrata. β IFN from secondary pig kidney cells was very effective against Swine Vesicular Disease Virus (SVDV), whereas no activity was detected against porcine Rotavirus; Aujeszky's disease virus, BUK strain, proved to be of intermediate sensitivity. The results of these latter experiments are discussed, with regard to the cells used and to the IFN sensitivity of the tested viruses.  相似文献   
53.
《Field Crops Research》1987,16(4):323-335
The responses to different water treatments of two sorghum (Sorghum bicolor (L.) Moench) cultivars, a hybrid (CSH 8) and a local variety (M 35-1), were studied on an Alfisol (Udic Rhodustalfs) at ICRISAT Centre, Patancheru during the post-rainy seasons of 1979/1980 and 1980/1981. Two water treatments, irrigated and drought-stress, were created by applying water five or three times during each of the growing seasons. Observed responses were compared with the simulated data using the sorghum simulation model SORGF. Neither observed nor simulated durations of growth stages were affected by drought-stress. Comparisons between observed and simulated duration of growth stages showed that the model simulated phenological development with good accuracy. Drought-stress coefficient calculations were based on the availability of water in the soil profile; simulated drought-stress coefficients agreed well with observed values. Observed and simulated grain yields of CSH 8 were higher than those of M 35-1 under both the irrigated and drought-stressed conditions. The correlation coefficients between observed and simulated total dry matter and grain yield data pooled over two water treatments, two cultivars, and two seasons were respectively 0.80 and 0.92. Comparisons between observed and simulated reductions in TDM and grain yield showed that the model is sufficiently sensitive to simulate the response of sorghum to drought-stress.  相似文献   
54.
Hydramethylnon (AC 217,300) is a new amidinohydrazone insecticide registered under the trade names Amdro for control of the red imported fire ant and Combat and Maxforce for use against cockroaches. While this compound is slow acting, no major perturbations in either sensory or motor neurons of poisoned insects have been observed. However, symptoms of intoxication were accompanied by markedly depressed rates of oxygen consumption. Inhibition of cellular respiration was also observed in Chinese hamster ovary cells with an IC50 of 2 × 10−6 M after a 30-min uncubation. This inhibition was not reversible by repeated washing with fresh medium or by prolonged incubation. A systematic investigation of the effects of hydramethylnon on mitochondrial respiration showed hydramethylnon to be a potent inhibitor of electron transport. Sequential isolation of the coupling sites of the electron transport chain with different substrates showed that hydramethylnon is an inhibitor of the electron transport chain in the region of coupling site II.  相似文献   
55.
This paper reports the results of two feeding experiments in which oyster larvae (Crassostrea virginica) were grown to metamorphosis on microencapsulated diets, and provides the first successful case of culturing oyster larvae to metamorphosis on an artificial diet. Five to 25% of the larvae fed microencapsulated diets grew to the “eyed” stage in 22–25 days. About 2–20% of these “eyed” larvae metamorphosed and settled and 25–40% of these settled larvae produced spat (> 0.05 mm). Two concentrations of two microencapsulated diets were tested; results indicated that diet concentration affects larval growth and development.Microcapsules with capsule walls made of a lipid mixture containing ethyl cellulose and stearic acid improved the retention of water-soluble components. Capsules were more stable at low temperature (5°C) than at higher temperatures (22 and 28°C). Inclusion of lipid algal extract in gelatin-acacia capsules promoted better growth of larvae than those not containing the algal extract. This suggests that attractants or phagostimulants could play an important role in microencapsulated diets.  相似文献   
56.
The effects of a range of pyrethroids on end-plate potentials and muscle action potentials were studied in the pectoralis nerve-muscle preparation of the clawed frog, Xenopus laevis. The noncyano pyrethroids allethrin, cismethrin, bioresmethrin, and IR-cisphenothrin caused moderate presynaptic repetitive activity only, resulting in the occurrence of multiple end-plate potentials (epps). Trains of repetitive muscle action potentials without presynaptic repetitive activity were observed after the α-ethynyl pyrethroid S-5655 and after the α-cyano pyrethroids cypermethrin, deltamethrin, FCR 1272, and FCR 2769. An intermediate group of pyrethroids consisting of the non-cyano compounds 1R-permethrin, des-cyano-deltamethrin, NAK 1901 and NAK 1963, and the α-cyano pyrethroids cyphenothrin and fenvalerate caused both types of effect. The insecticidally inactive S-enantiomers of permethrin had no effect on the nerve-muscle preparation. Trains of repetitive action potentials in pyrethroid-treated muscle fibers were followed by a depolarizing afterpotential which in general decayed more rapidly for the non-cyano pyrethroids than for the α-cyano pyrethroids. The rate of decay of the depolarizing afterpotential decreased gradually as the temperature was lowered, whereas the pre- and postsynaptic repetitive activity remained largely unaffected over a large temperature range. It is concluded that in muscle membrane like in nerve membrane the pyrethroid-induced repetitive activity is due to a prolongation of the sodium current and that a clear distinction between non-cyano pyrethroids on the one hand and α-cyano compounds on the other cannot be made on the basis of the present results.  相似文献   
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58.
Maltogenic amylase originated from Lactobacillus plantarum (LpMA) was studied to investigate its applicability as an antistaling enzyme. The differential scanning calorimetry (DSC) results demonstrated that the bread treated with purified LpMA exhibited a retrogradation peak that was 65% that of the control bread. Then, for the purpose of practically using L. plantarum as an antistaling agent, the expression of LpMA in L. plantarum was enhanced by growth on a modified medium; the LpMA expression of L. plantarum grown on De Man, Rogosa and Sharpe (MRS) medium supplemented with an additional 6% glucose was 54 times higher than that of L. plantarum grown on the original MRS medium. The side chain length distribution analysis showed that the cell extract of L. plantarum (CELP) tended to prefer to hydrolyzes the long side chains of amylopectin (>30). During storage for 9 days at 4 °C, the bread treated with CELP exhibited a 25% slower retrogradation rate and 63% lower hardness relative to the control bread, indicating that the CELP is a potential candidate for use as an antistaling agent.  相似文献   
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