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31.
Of the numerous fractions obtained from the crude plant extracts of Chenopodium ambrosioides, Conyza dioscordisis and Convolvulus arvensis, 11 were found to be active against stored grain pests. The chemical structures of compounds present in the 11 fractions were found by gas chromatography/mass spectrometry to include predominantly long-chain fatty acid esters of hexadecanoic, arachidonic, and octadecanoic acids.  相似文献   
32.
Veterinary pharmacovigilance has shown a remarkable development in recent years. After presenting briefly the regulatory context, this paper considers the scope of veterinary pharmacovigilance, causality assessment of suspected adverse drug reactions (ADRs), the systems existing in different countries and the evolution for the coming years. The involvement of veterinary research and teaching institutions should certainly become more important in this cross-road activity.  相似文献   
33.
The ontogeny of testicular inhibin/activin in ducks was investigated. Testicular localization of three inhibin/activin subunits (α, βA and βB) was determined in embryonic and newly hatched ducks from 12 days of incubation to 1 day of age, in immature ducks and in adult ducks. In the duck embryonic testis, positive α‐subunit immunostaining was first detected in the Leydig cells and Sertoli cells on day 15 of incubation, whereas βA‐subunit and βB‐subunit immunostaining were found in Sertoli cells and primary germ cells on day 18 of incubation. In 1 month old ducks, intense staining of α‐subunit was present in the seminiferous epithelium consistent with localization in Sertoli cells and primary germ cells, and the immunostaining of the βA‐ and βB‐subunit was also present in Sertoli cells and primary germ cells. Specific immunostaining with inhibin/activin α‐, βA‐ and βB‐subunits antisera occurred in Sertoli cells in the adult duck testes. In conclusion, it was shown that, in the duck testis, the majority of α‐, βA‐ and βB‐subunits are colocalized in Sertoli cells with a certain degree of staining in germ cells and the α‐subunit is present in Leydig cells of embryonic testes before day 18 of incubation. These results indicate that Sertoli cells and possibly germ cells in the embryonic testes of late stage of incubation and newly hatched ducks, immature ducks and mature ducks may produce bioactive inhibin dimers, inhibin A and inhibin B, as a possible regulator of follicle‐stimulating hormone secretion. Free inhibin/activin subunits and their dimers may also play an autocrine/paracrine role in the development of the testis and spermatogenesis. Furthermore, early onset of the α‐subunit in duck testes indicates that it may have an autocrine/paracrine effect on steroid hormones, which is important for sex differentiation.  相似文献   
34.
35.
Effective management of potato cyst nematodes (PCNs) requires simple, rapid and accurate identification and quantification of field populations. Soil samples from a survey of 484 fields in potato rotations in England and Wales were used to compare the identification and quantification of PCNs using IEF, PCR, ELISA and bait plant tests. The cyst counts and bait plant test revealed that 64.3% of field samples contained PCNs. Bait plant tests increased the detection rate of PCNs in field samples by 4–6.4%. This means that some infestations are cryptic and would not normally be detected by standard counts. IEF, PCR and ELISA methods distinguished between Globodera rostochiensis and G pallida and were able to register mixed populations; however they were not in full agreement. All methods suggested that G pallida is the dominant species in the field samples tested. The PCR results indicated that 66% of field samples contained pure G pallida, 8% contained pure G rostochiensis and 26% contained mixtures of the two species. Estimates of the relative process times taken per sample in the PCR, IEF and ELISA techniques are given. © 2001 Society of Chemical Industry  相似文献   
36.
Haematological estimations and serum biochemical analyses were made on 100 samples collected from clinically healthy Hijin racing camels (Camelus dromedarius) in Kuwait. The red blood cell counts, packed cell volume, haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and total white blood cell counts were estimated. In the serum biochemical analyses, sodium, potassium, iron, calcium, phosphorus, magnesium, total bilirubin, blood urea nitrogen, creatinine, glucose, total protein and cholesterol concentrations were measured, as were the alanine aminotransferase, aspartate aminotransferase, -glutamyltransferase, creatine kinase and alkaline phosphatase activities. The results are discussed in relation to other findings reported in camels.  相似文献   
37.
Two promising selected land races of safflower ( Carthamns tinctorious L.) designated as line 11 and line 13, together with the local variety Giza 1 , were examined under three levels of moisture depletions, i.e. 40, 60 and 80 % ASMD at Fayoum, Middle Egypt during 1986/87 and 1987/88 seasons. In both growing seasons, the second irrigation treatment i.e. 60 % ASMD gave the highest means for growth characters as well as seed yield and most of its components. Seed oil content per cent exhibited an increased as soil moisture depletion increased with no significant difference between entries. Safflower entries showed clear differences in some yield components which compensate each other and resulted in no significant difference in seed yield per hectar.
Consumptive use of water by safflower plants increased as the available soil moisture around the root zone increased. No significant differences were found in water consumed by safflower entries used in all experiments.
In the two experimental seasons, the best water use efficiency (WUE) for seed production was obtained also from the second treatment (60 % ASMD). The line 11 gave the best WUE.  相似文献   
38.
To clarify the morphological and immunohistochemical characteristics in mares with granulosa theca cell tumor (GTCT), the localization of inhibin subunits (alpha, betaA, betaB) and aromatase in the granulosa cell layers and theca layers in the ovarian follicles were determined by immunohistochemical staining. The follicles were obtained from the ovaries of 6 mares with GTCT and 4 normal mares as controls. Immunohistochemically, inhibin alpha-subunit was localized in the granulosa cells of all follicles showing different sizes in all GTCT cases and betaA- subunit was localized in two GTCT cases in all sized follicles. But inhibin betaB- subunit and aromatase were not localized in GTCT cases. On the other hand, inhibin alpha-, betaA-, and betaB-subunits and aromatase were localized in the large and medium sized follicles, but inhibin betaA- and betaB-subunits and aromatase were not stained in the small sized follicles in normal cases. These findings suggest that some mares with GTCT can secrete dimeric inhibin (inhibin A), but all GTCT cases cannot secrete inhibin B. By the results of aromatase staining it is clear that testosterone is not converted into estradiol due to the lack of aromatase in the GTCT follicles.  相似文献   
39.
A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.  相似文献   
40.
ABSTRACT The PaEXG2 gene, encoding an exo-beta-1,3-glucanase, was isolated from the biocontrol agent Pichia anomala strain K. PaEXG2 has the capacity for coding an acidic protein of 427 amino acids with a predicted molecular weight of 45.7 kDa, a calculated pI of 4.7, and one potential N-glycosylation site. PaEXG2 was disrupted by the insertion of the URA3 marker gene, encoding orotidine monophosphate decarboxylase in strain KU1, a uracil auxotroph derived from strain K. Strain KU1 showed inferior biocontrol activity and colonization of wounds on apples, compared to the prototrophic strain. Antagonism and colonization were recovered after the restoration of prototrophy by transformation with the URA3 gene. Integrative transformation was shown to be mostly ectopic in strain K descendants (only 4% of integration by homologous recombination). PaEXG2 disruption abolished all detectable extracellular exo-beta-1,3-glucanase activity in vitro and in situ but did not affect biocontrol of Botrytis cinerea on wounded apples.  相似文献   
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