Effects of chlordimeform on mitochondria from eggs of Spodoptera littoralis     

Clemens Kötter 《Pesticide biochemistry and physiology》1978,9(3):263-267

Mitochondria were isolated from eggs of Spodoptera littoralis. With succinate (+pyruvate) as substrate, respiratory control ratios between 1.70 and 2.54 were obtained. Uncouplers and the energy transfer inhibitor oligomycin influenced these mitochondria in the well-known manner. The uncoupling activity of chlordimeform in vitro was very weak and decreased with increasing age of the eggs. Electron transport in mitochondria from chlordimeform-treated eggs was not uncoupled. Therefore, it is concluded that the ovicidal effect of this pesticide is not due to its uncoupling effect.  相似文献   

Variation and genetic parameters of axial resin canal features in clones and families of Pinus radiata     

Govina  James Kudjo  Apiolaza  Luis A.  Altaner  Clemens M. 《New Forests》2021,52(1):167-176

New Forests - Resin canal features are associated with significant economic losses to appearance grade Pinus radiata timber. This study investigated the variation in resin canal features in young,...  相似文献   

Analyse der K-Düngewirkung an einem Humuspelosol-Standort     

E. Schlichting  G. Clemens 《植物养料与土壤学杂志》1984,147(3):361-370

Analysis of the K-fertilizing effect on a Humuspelosol site The result of a K-fertilizing experiment with a nearly pure cereal rotation on a Humuspelosol (eutric Cambisol) 1973 poor in ?available”? K and strongly K fixing (see Fig. 1) was analysed by investigating plant and soil samples taken 1981 and 1982. About 1200 kg K₂₀/ha were fixed, thus did not change the ?available”? K, but restored the reserves to such an extent that the plants were supplied sufficiently from it. Amounts exceeding 2400 kg K₂O/ha could not be held in the main rooting space (0–40 cm). Even 180 kg K₂O/ha/a in the course of the experiment restored the reserves sufficiently, leading to an (at best) normal fertilizer requirement at this site (with low Mg supply possibly limiting the yields), despite its still low content of ?available”? K. Apparently, here the LUFA threshold values are too high and/or the lactate method is not a suitable basis for statements about the fertilizer requirement.  相似文献   

Mating behavior: facilitation in the female rat after cortical application of potassium chloride     

L G Clemens  K Wallen  R A Gorski 《Science (New York, N.Y.)》1967,157(793):1208-1209

Mating behavior in ovariectomized female rats treated with estrogen can be greatly enhanced by subcutaneous injections of progesterone. Application of potassium chloride to the cortex of females previously treated with estrogen can also induce greatly increased sexual receptivity as indicated by the lordosis response. This facilitation of mating behavior by a treatment known to cause functional decortication suggests that mechanisms mediating female mating behavior are under tonic inhibition by an inhibitory system which involves the cerebral cortex.  相似文献   

A class of potent antimalarials and their specific accumulation in infected erythrocytes     

Wengelnik K  Vidal V  Ancelin ML  Cathiard AM  Morgat JL  Kocken CH  Calas M  Herrera S  Thomas AW  Vial HJ 《Science (New York, N.Y.)》2002,295(5558):1311-1314

During asexual development within erythrocytes, malaria parasites synthesize considerable amounts of membrane. This activity provides an attractive target for chemotherapy because it is absent from mature erythrocytes. We found that compounds that inhibit phosphatidylcholine biosynthesis de novo from choline were potent antimalarial drugs. The lead compound, G25, potently inhibited in vitro growth of the human malaria parasites Plasmodium falciparum and P. vivax and was 1000-fold less toxic to mammalian cell lines. A radioactive derivative specifically accumulated in infected erythrocytes to levels several hundredfold higher than in the surrounding medium, and very low dose G25 therapy completely cured monkeys infected with P. falciparum and P. cynomolgi.  相似文献   

Crystal structure of the malaria vaccine candidate apical membrane antigen 1     

Pizarro JC  Vulliez-Le Normand B  Chesne-Seck ML  Collins CR  Withers-Martinez C  Hackett F  Blackman MJ  Faber BW  Remarque EJ  Kocken CH  Thomas AW  Bentley GA 《Science (New York, N.Y.)》2005,308(5720):408-411

Apical membrane antigen 1 from Plasmodium is a leading malaria vaccine candidate. The protein is essential for host-cell invasion, but its molecular function is unknown. The crystal structure of the three domains comprising the ectoplasmic region of the antigen from P. vivax, solved at 1.8 angstrom resolution, shows that domains I and II belong to the PAN motif, which defines a superfamily of protein folds implicated in receptor binding. We also mapped the epitope of an invasion-inhibitory monoclonal antibody specific for the P. falciparum ortholog and modeled this to the structure. The location of the epitope and current knowledge on structure-function correlations for PAN domains together suggest a receptor-binding role during invasion in which domain II plays a critical part. These results are likely to aid vaccine and drug design.  相似文献   

Ammonia and Nitrous Oxide Emissions after Landspreading of Slurry as Influenced by Application Technique and Dry Matter-Reduction. II. Short Term Nitrous Oxide Emissions     

Joachim Clemens  Robert Vandr  Martin Kaupenjohann  Heiner Goldbach 《植物养料与土壤学杂志》1997,160(4):491-496

Strategies reducing NH₃ volatilisation from slurry include separation of slurry, special application techniques and additives. We studied the impact of manure separation and application technique on N₂O release after manure application. Untreated and separated cattle slurry (dry matter content of 7.1% and 4.4%, respectively) was applied to winter wheat using broadcast and banded application and injection. The N₂O emissions were measured at high frequency for 14 to 20 days after slurry treatment by the closed chamber method. Manured plots showed significantly higher N₂O emissions than the control plots but neither dry matter reduction of slurry nor application technique significantly influenced the N₂O emissions. The variability of N₂O emission was influenced by the application technique and increased in the order: banded application – injection – broadcast application. There was no correlation between NH₃ losses from applied slurry and N₂O emissions. Thus reducing ammonia volatilisation will not necessarily increase N₂O emissions.  相似文献   

Do summer temperatures trigger spring maturation in Pacific lamprey,Entosphenus tridentatus?     

B. J. Clemens  S. van de Wetering  J. Kaufman  R. A. Holt  C. B. Schreck 《Ecology of Freshwater Fish》2009,18(3):418-426

Abstract –  Pacific lamprey, Entosphenus tridentatus , return to streams and use somatic energy to fuel maturation. Body size decreases, the lamprey mature, spawn, and then die. We predicted that warm, summer temperatures (>20 °C) would accentuate shrinkage in body size, and expedite sexual maturation and subsequent death. We compared fish reared in the laboratory at diel fluctuating temperatures of 20–24 °C (mean = 21.8 °C) with fish reared at cooler temperatures (13.6 °C). The results confirmed our predictions. Lamprey from the warm water group showed significantly greater proportional decreases in body weight following the summer temperature treatments than fish from the cool water group. A greater proportion of warm water fish sexually matured (100%) and died (97%) the following spring than cool water fish (53% sexually mature, 61% died). Females tended to mature and die earlier than males, most obviously in the warm water group.  相似文献   

Effects of feed and water restriction and receiving diet crude protein on feeder pig performance   总被引：1，自引：0，他引：1  

M C Brumm  G W Jesse  H F Mayes  G M Zinn  E T Clemens 《Journal of animal science》1987,64(6):1606-1611

Two experiments were conducted to determine the effects of feed and water restriction and receiving diet crude protein level on feeder pig performance. In Exp. 1, a total of 239 commingled feeder pigs transported over 1,000 km were used in two trials. Pigs given access to feed and water (FW) at the market weighed more (P less than .0001) following marketing and transport than pigs given no feed and water (N) for the comparable 25-h market period (20.7 vs 19.6 kg). While FW pigs weighed less (P less than .02) than N pigs at the conclusion of the trials (93.9 vs 96.6 kg), there was no effect (P greater than .1) on overall average daily gain (.32 vs .35). There were no effects of receiving diets containing 12, 16 or 20% crude protein on daily gain, daily feed intake or feed efficiency for the overall growing-finishing period. Scour scores on d 8, 9, 10, 11, 13 and 14 post-arrival increased (P less than .01) with increased levels of protein in the receiving diets. In Exp. 2, a total of 360 crossbred feeder pigs was mixed and moved from a nursery to grower-finisher facilities in three trials, given feed and water access immediately (FWG) or denied access for 44 h (NG). At the end of the 44-h period, FWG pigs were heavier than NG pigs (P less than .0001; 18.3 vs 16.7 kg). There was no treatment effect on overall pig weight, daily gain or feed efficiency.  相似文献   

Fatty acid composition of bulls and steers as influenced by age and dietary energy level   总被引：1，自引：0，他引：1  

E Clemens  V Arthaud  R Mandigo  W Woods 《Journal of animal science》1973,37(6):1326-1331

  相似文献