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The biocontrol properties of Trichoderma species are well documented, but their effectiveness in antagonism of the problematic Sclerotium cepivorum, the causal agent of white rot in Allium species, appears limited with reports of significant control only relating to deliberately-mutated strains of Trichoderma. Our previous studies have indicated the possibility of using selected naturally-occurring strains of the antagonist in the suppression of other diseases; now in vitro and controlled environment in vivo studies have indicated that a degree of control of Onion White Rot is possible, and that the selected antagonist strains can be used in integrated treatments with Iprodione to good effect. The possible value of such treatments is considered in light of other approaches to the suppression of this continuing problem.  相似文献   
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Each year, there are still between 300-500 million clinical cases of malaria and over one million deaths due to the disease, 90% of which occur in Africa south of the Sahara. In all continents, malaria risk is highest in remote rural areas where poverty abounds, population densities are low and the quality and coverage of the health services are poor or in existent. A sustained impact on the malaria burden can only be achieved through the cost-effective use of current tools, by including malaria in health sector development and inter-sectorial action, by mobilizing malaria control within communities and by investing in new and more effective tools. This paper highlights some of the constraints faced by countries in controlling malaria and outlines the priority activities that are being carried out to address these constraints within both communities and the health services. It aims to be set the scene for the papers of this Centenary book which address some of these issues in more detail.  相似文献   
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This study examined the influence of a GnRH agonist containing either 450 or 750 microg of deslorelin in an implant form or a gonadorelin injection (control) to induce ovulation in the Ovsynch protocol on pregnancy rates (PR), embryonic loss, and ovarian function in 593 lactating Holstein cows. Cows were given two injections of PGF2alpha 14 days apart, followed 14 days later by the Ovsynch protocol, and were timed artificially inseminated (TAI) at 68 +/- 3 days postpartum. Blood samples for determination of plasma progesterone concentrations were collected at 24 and 10 days prior to and 11 days after TAI. Pregnancy was diagnosed on Day 27 and reconfirmed on Day 41 after TAI. Non-pregnant, not re-inseminated cows at Day 27 had their ovaries examined by ultrasonography, and the number and size of follicles and presence of luteal tissue were determined. Simultaneously, these cows were re-synchronized with the Ovsynch protocol. Pregnancy during the re-synchronization period was determined between 35 and 41 days after insemination. On Day 27, PR were higher for control (39.0%) and deslorelin 450 microg (DESLORELIN 450) implant (41.3%) than for those receiving the deslorelin 750 microg (DESLORELIN 750) implant (27.5%; P<0.05). Pregnancy losses tended to decrease for DESLORELIN 450 compared with control (5.0% versus 12.7%; P<0.13). Plasma progesterone concentrations did not differ significantly among treatments. Deslorelin suppressed ovarian activity and decreased PR during the re-synchronization period compared with control. The percentage of non-pregnant animals that were re-inseminated by Day 27 was less for deslorelin compared with control. In conclusion, incorporation of an implant of the GnRH agonist deslorelin to induce ovulation in the Ovsynch protocol has the potential to reduce pregnancy losses, but the response was dependent upon implant concentration. Evaluation of lower doses to minimize the negative effects on subsequent fertility is warranted.  相似文献   
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After removal of the ovaries approximately 20% of dogs develop urinary incontinence. Removal of the gonads results in estrogen deficiency and chronic elevation in the production and secretion of FSH and LH. The gonadotrophins may directly or indirectly, adversely affect the sphincter function of the urethra. Estrogen replacement therapy and treatment with sympathomimetics, such as ephedrine or phenylpropanolamine (PPA), are effective only in some of the affected dogs, and many of these subsequently become nonresponsive. Since the role of the elevated gonadotrophins has not been elucidated, we used depot preparations of GnRH analogues to down-regulate gonadotrophins once or twice in 13 ovariectomized (ovx), incontinent dogs, which were either refractory to alpha-adrenergics (n=11) or in which alpha-adrenergics were contraindicated (n=2). Dogs were treated with leuprolide, deslorelin, buserelin or triptorelin. In 7 dogs treatments with GnRH analogues alone (n=11) resulted in continence for 50-738 days (mean 247). In all dogs except one, where GnRH treatments did not resolve the incontinence completely, additional treatment with phenylpropanolamine was successful. With additional treatment of phenylpropanolamine complete continence was restored for 21-367 days (mean 159). All treatments caused long-term reduction of circulating FSH and LH concentrations to very low or undetectable levels. No adverse effects of treatments were observed.  相似文献   
7.
The synchrony of ovulation was examined in superstimulated heifers that had a downregulated pituitary gland and which were induced to ovulate by injection of exogenous LH. The pituitary was downregulated and desensitized to GnRH by treatment with the GnRH agonist deslorelin. Nulliparous heifers (3.5 yr old) at random stages of the estrous cycle were assigned to 1 of 3 groups, and on Day -7 received the following treatments: Group 1 (control, n = 8), 1 norgestomet ear implant; Group 2 (GnRH agonist, n = 8); Group 3 (GnRH agonist-LH protocol, n = 8), 2 deslorelin ear implants. Ovarian follicle growth in all heifers was superstimulated with twice-daily intramuscular injections of FSH (Folltropin-V): Day O, 40 mg (80 mg total dose); Day 1, 30 mg; Day 2; 20 mg; Day 3, 10 mg. On Day 2, all heifers were given a luteolytic dose of PGF (7 A.M.), Norgestomet implants were removed from heifers in Group 1 (6 P.M.). Heifers in Group 3 were given an injection of 25 mg, i.m. porcine LH (Lutropin) on Day 4 (4 P.M.). Ovarian follicle status was monitored at 8-h intervals from Day 3 (8 A.M.) to Day 6 (4 P.M.) using an Aloka Echo Camera and 7.5 MHz transducer. Heifers in Groups 2 and 3 exhibited estrus earlier (P < 0.05) than heifers in Group 1. Heifers in Group 2 did not have a preovulatory LH surge and they did not ovulate. Individual control heifers in Group 1 ovulated between 12 A.M. on Day 5 and 8 A.M. on Day 6. Heifers with deslorelin implants and injected with LH in Group 3 ovulated between 4 P.M. on Day 5 and 8 A.M. on Day 6. It was confirmed that superstimulated heifers with GnRH agonist implants can be induced to ovulate with LH. It was also demonstrated that ovulation is closely synchronized after injection of LH. Thus, a single, fixed-time insemination schedule could be used in a GnRH agonist-LH superovulation protocol, with significant practical and economic advantages for superovulation and embryo transfer programs.  相似文献   
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Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
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The labelling reagent 2-[18F]fluoroethylazide was used in a traceless Staudinger ligation. This reaction was employed to obtain the GABAA receptor binding 6-benzyl-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid (2-[18F]fluoroethyl) amide. The radiotracer was prepared with a non-decay corrected radiochemical yield of 7%, a radiochemical purity >95% and a specific radioactivity of 0.9 GBq/μmol. The compound showed low brain penetration in normal rats. A series of fluoroalkyl 4-quinolone analogues with nanomolar to sub-nanomolar affinity for the GABAA receptor has been prepared as well.  相似文献   
10.
The alpha-helical coiled coil can adopt a variety of topologies, among the most common of which are parallel and antiparallel dimers and trimers. We present Multicoil2, an algorithm that predicts both the location and oligomerization state (two versus three helices) of coiled coils in protein sequences. Multicoil2 combines the pairwise correlations of the previous Multicoil method with the flexibility of Hidden Markov Models (HMMs) in a Markov Random Field (MRF). The resulting algorithm integrates sequence features, including pairwise interactions, through multinomial logistic regression to devise an optimized scoring function for distinguishing dimer, trimer and non-coiled-coil oligomerization states; this scoring function is used to produce Markov Random Field potentials that incorporate pairwise correlations localized in sequence. Multicoil2 significantly improves both coiled-coil detection and dimer versus trimer state prediction over the original Multicoil algorithm retrained on a newly-constructed database of coiled-coil sequences. The new database, comprised of 2,105 sequences containing 124,088 residues, includes reliable structural annotations based on experimental data in the literature. Notably, the enhanced performance of Multicoil2 is evident when tested in stringent leave-family-out cross-validation on the new database, reflecting expected performance on challenging new prediction targets that have minimal sequence similarity to known coiled-coil families. The Multicoil2 program and training database are available for download from http://multicoil2.csail.mit.edu.  相似文献   
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