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11.
12.
JL Yaniz M Lopez-Bejar P Santolaria J Rutllant & F Lopez-Gatius 《Reproduction in domestic animals》2002,37(2):75-80
This review focuses on factors associated with the development of intraperitoneal insemination in mammals. Findings to date indicate that fertility improves as the sperm cell concentration rises, but that the optimal sperm number differs in each species. Sperm washing before intraperitoneal insemination favours fertility. Peritoneal fluid shows a variable effect on spermatozoa, depending on the hormonal status of the female. The optimal time for insemination appears to be just prior to ovulation. The technique may be performed either through the abdominal or the vaginal wall. Verification of sperm deposition in the proximity of the ovaries improves fertility rates. Although associated with some risk of infection and an immune reaction against spermatozoa, the intraperitoneal technique rarely gives rise to severe anaphylactic shock, peritonitis, adhesion formation and the production of anti‐sperm antibodies and these complications may be prevented by adequate sperm pretreatment and antibiotic therapy. The success of intraperitoneal insemination in humans, with results comparable with those of intrauterine insemination in the treatment of infertility, suggest the potential use of this technique in domestic mammals, especially in those in which intrauterine insemination poses practical difficulties. Some of the methods applied in human intraperitoneal insemination, such as confirming the position of the needle in the peritoneal cavity, and sperm pre‐treatments might also improve results in domestic species. Conversely, the use of the animal model should help to develop some aspects of this technique in humans. 相似文献
13.
The objectives of this study were to optimize RAPD and AFLP techniques in B. catharticus, and to determine the genetic variability of populations and commercial prairie grass cultivars with the aforementioned molecular
markers. Two populations with contrasting morphological characteristics were evaluated from individual and bulked DNA samples
using RAPD markers. Both analyses showed a similar information about inter population variability. Each accession was sampled
by a single leaf bulk of 10 plants. Accession similarities were established with 276 RAPD and 714 AFLP bands using Jaccard
similarity coefficient. The dendrogram of the accessions using RAPD markers showed that they shared high similarity values
(>94%). A similar result was obtained with AFLP markers (similarity values >98%), revealing a narrow genetic basis in the
analyzed accessions. Consequently, molecular characterization of germplasm should be considered in addition to morphological
criteria, to choose the parental genotypes for breeding programs of this forage crop. The AFLP technique was more efficient
to detect DNA polymorphism in our experiments and unique fingerprints were detected for all the accessions. RAPD is a simple
and non expensive technique, suitable to estimate genetic similarity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
Pérez-Gálvez A Rios JJ Mínguez-Mosquera MI 《Journal of agricultural and food chemistry》2005,53(12):4820-4826
The high-temperature treatment of paprika oleoresins (Capsicum annuum L.) modified the carotenoid profile, yielding several degradation products, which were analyzed by HPLC-APCI-MS. From the initial MS data, compounds were grouped in two sets. Set 1 grouped compounds with m/z 495, and set 2 included compounds with m/z 479, in both cases for the protonated molecular mass. Two compounds of the first set were tentatively identified as 9,10,11,12,13,14,19,20-octanor-capsorubin (compound II) and 9,10,11,12,13,14,19,20-octanor-5,6-epoxide-capsanthin (compound IV), after isolation by semipreparative HPLC and analysis by EI-MS. Compounds VII, VIII, and IX from set 2 were assigned as 9,10,11,12,13,14,19,20-octanor-capsanthin and isomers, respectively. As these compounds were the major products formed in the thermal process, it was possible to apply derivatization techniques (hydrogenation and silylation) to analyze them by EI-MS, before and after chemical derivatization. Taking into account structures of the degradation products, the cyclization of polyolefins could be considered as the general reaction pathway in thermally induced reactions, yielding in the present study xylene as byproduct and the corresponding nor-carotenoids. 相似文献
15.
Immunotherapy of cancer: immunospecific rejection of tumors in recipients of neuraminidase-treated tumor cells plus BCG 总被引:9,自引:0,他引:9
Firmly established methylcholanthrene fibrosarcomas in syngeneic mice will totally disappear if the hosts are treated with living tumor cells that have been exposed to Vibrio cholerae neuraminidase in vitro. The effect is magnified by the simultanieous injection of a nonspecific immunostimulant, BCG. The rejection of the methylcholanthrene tumor is immunospecific and can be induced only with tumor cells, treated with Vibrio cholerae neuraminidase, identical in type with the growing tumor. 相似文献
16.
17.
Montenegro MA Rios Ade O Mercadante AZ Nazareno MA Borsarelli CD 《Journal of agricultural and food chemistry》2004,52(2):367-373
The photosensitized isomerization reaction of the natural cis carotenoid bixin (methyl hydrogen 9'-cis-6, 6'-diapocarotene-6, 6'-dioate) with rose bengal or methylene blue as the sensitizer in acetonitrile/methanol (1:1) solution was studied using UV-vis spectroscopy, high-performance liquid chromatography (HPLC), and time-resolved spectroscopic techniques, such as laser-flash photolysis and singlet oxygen phosphorescence detection. In both N(2)- and air-saturated solutions, the main product formed was all-trans-bixin. The observed isomerization rate constants, k(obs), decreased in the presence of air or with increase in the bixin concentration, suggesting the participation of the excited triplet state of bixin, (3)Bix, as precursor of the cis--> trans process. On the other hand, bixin solutions in the absence of sensitizer and/or light did not degrade, indicating that the ground state of bixin is stable to thermal isomerization at room temperature. Time-resolved spectroscopic experiments confirmed the formation of the excited triplet state of bixin and its deactivation by ground state bixin and molecular oxygen quenching processes. The primary isomerization products only degraded in the presence of air and under prolonged illumination conditions, probably due to the formation of oxidation products by reaction with singlet molecular oxygen. An energy-transfer mechanism was used to explain the observed results for the bixin transformations, and the consequences for food color are discussed. 相似文献
18.
Simulation study of the competitive ability of erect, semi-erect and prostrate cowpea (Vigna unguiculata) genotypes 总被引:1,自引:1,他引:1
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments. 相似文献
19.
Comparative population structure and trichothecene mycotoxin profiling of Fusarium graminearum from corn and wheat in Ontario,central Canada 下载免费PDF全文
Fusarium graminearum causes fusarium head blight (FHB) of wheat and gibberella ear rot (GER) of corn in Canada and also contaminates grains with trichothecene mycotoxins. Very little is known about trichothecene diversity and population structure of the fungus from corn in Ontario, central Canada. Trichothecene genotypes of F. graminearum isolated from corn (n = 452) and wheat (n = 110) from 2010 to 2012 were identified. All the isolates were deoxynivalenol (DON) type. About 96% of corn isolates and 98% of wheat isolates were 15‐acetyl deoxynivalenol (15ADON) type. The fungal population structures from corn (n = 313) and wheat (n = 73) were compared using 10 variable number tandem repeat (VNTR) markers. The fungal populations and subpopulations categorized based on host, cultivar groups, years and geography showed high gene (H = 0.818–0.928) and genotypic (GD = 0.999–1.00) diversity. Gene flow was also high between corn and wheat population pairs (Nm = 8.212), and subpopulation pairs within corn (Nm = 7.13–23.614) or wheat (Nm = 19.483) populations. Phylogenetic analysis revealed that isolates from both hosts were F. graminearum clade 7. These findings provide baseline data on 3‐acetyl deoxynivalenol (3ADON) and 15ADON profiles of F. graminearum isolates from corn in Canada and are useful in evaluating mycotoxin contamination risks in corn and wheat grains. Understanding the fungal genetic structure will assist evaluation and development of resistant cultivars/germplasm for FHB on wheat and GER on corn. 相似文献
20.
Meiotic Response of In vitro Matured Canine Oocytes under Different Proteins and Heterologous Hormone Supplementation 总被引:2,自引:0,他引:2
The impact of TCM‐199 supplemented with different proteins and heterologous hormones on the in vitro maturation (IVM) rate of bitch oocytes was evaluated by nuclear staining under fluorescence microscopy. Oocytes were recovered by slicing of ovaries from bitches presented at various stages of oestrous cycle to ovariohysterectomy. The basic culture medium was TCM‐199 supplemented with 25 mM Hepes/l, with 10% heat‐inactivated oestrous cow serum (ECS), 50 μg/ml gentamicin, 2.2 mg/ml sodium bicarbonate and 22‐μg/ml pyruvic acid, 1.0‐μg/ml oestradiol (E 8875; Sigma), 0.5‐μg/ml follicle‐stimulating hormone (FSH) (Folltropin‐V; Vetrepharm Inc., Ontario, Canada) and 0.03 IU/ml human gonadotropin (hCG) (Profasi HP; Serono, Aubonne, Switzerland). Oocytes were distributed randomly between basic culture medium (control) and the corresponding experimental treatment. Hormone treatments were: oocytes cultured in; (1) medium without FSH, (2) control medium supplemented with 20 μg/ml oestradiol, or (3) medium supplemented with 1 μg/ml human somatotropin (hST; Humatrope, Lilly, Saint Cloud, France). The second experiment consisted of oocytes cultured in medium supplemented with 0.4% (w/v) bovine serum albumin (BSA, fraction V; Gibco Grand Island, NY, USA) instead of ECS, or oocytes cultured in medium with 10% inactivated oestrous bitch serum (EBS) instead of ECS. Oocytes were cultured in 100 μl droplets (up to 25 oocytes per drop) under mineral oil at 37°C in a 100% humidified atmosphere containing 5% CO2 in air. After 72 h of IVM, the highest rates (p < 0.05) of meiotic resumption were achieved with the 0.4% BSA supplementation. A positive influence on the metaphase II (MII) acquisition rate was observed with hST supplement. Oocytes cultured with 10% EBS supplementation did not develop to the MII stage. The results in this study show that the protein and hormone supplements to TCM‐199 culture medium tested did not promote the final steps of IVM of bitch oocytes. 相似文献