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1.
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
2.
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
3.
D Schams F Graf J Meyer B Graule M Mauthner C Wollny 《Journal of animal science》1991,69(4):1583-1592
Twelve second-lactation Deutsches Fleckvieh cows, (FV, a dual-purpose breed) and 12 German Black and White (BW, a dairy breed) were used to evaluate similarities and differences in the response to a prolonged-release formulation of sometribove (N-methionyl bovine somatotropin, bST). Cows were milked twice daily and fed a basic diet (70% corn silage, 30% alfalfa hay) ad libitum plus 1 kg of concentrate. Additionally, concentrates and supplements were offered at the rate of 1 kg for each 22 kg of milk produced above 12 kg/d. Six cows of each breed were treated s.c. with 500 mg of sometribove at 14-d intervals from wk 9 to 29 postpartum (pp). Blood was collected by jugular vein puncture once weekly from wk 7 to 33 pp and daily for 14 d after the first and last (11th) injection of bST. Somatotropin (ST), insulin-like growth factor I (IGF-I), insulin, thyroid hormones, nonesterified fatty acids (NEFA), liver enzymes, and blood metabolites were evaluated. During bST treatment, plasma ST increased significantly on d 7 in both breeds and then decreased on d 14 after injection. Plasma IGF-I was positively correlated with ST. Plasma NEFA were high on d 7 and decreased on d 14. In response to bST, the average milk yield increased for FV and BW cows by 5.1 kg/d (29.7%) and 5.0 kg/d (28%), respectively, and 4% fat-corrected milk (FCM) increased by 5.0 kg/d (28%) and 5.3 kg/d (19.9%), respectively. Milk content of fat, protein, lactose, number of somatic cells, and body weight were similar across treatments.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
To be successful, initiatives to improve smallholder’s goat production should directly address the needs and objectives of
the keepers while promoting rational use of local genetic resources. This paper identifies the objectives, constraints and
needs of goat farmers in southern Benin and discusses their relevance to the development of improvement programmes. Between
November and December 2005, structured questionnaires, focus group discussions and participant observation were used to collect
information from 38 goat farmers in two selected locations. Goats were kept mainly for sale whenever cash was needed. Traits
related to reproduction, to behaviour, to health and to meat production were considered equally important and were ranked
very highly by goat keepers. Increased net income per flock through increased number of marketable animals is the derived
breeding objective from the trait analysis. Disease outbreaks resulting in high mortality, poor housing, and feed shortages
were, in descending order, the most important problems. It was concluded that the development of initiatives to improve management
practices is an overriding priority. It will lead to increases in productivity in the short term and foster farmers’ participation
in the development of long-term improvement strategies, which should include selection and controlled mating. 相似文献
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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