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排序方式: 共有253条查询结果,搜索用时 15 毫秒
1.
J J Tarín S Pérez-Albalá A Aguilar J Mi?arro C Hermenegildo A Cano 《Biology of reproduction》1999,61(5):1347-1355
Aims of this study were to analyze the long-term effects of postovulatory aging of mouse oocytes on 1) reproductive traits of parental (F(0)) and first (F(1))-generation females (pregnancy rate, gestation length, litter size, perinatal death, and sex ratio of offspring) and 2) developmental and behavioral variables of F(1) and second-generation (F(2)) offspring (birth weight and weight gain during preweaning development, postnatal day of attainment of immediate righting, spontaneous motor activity, and passive and active conditioned learning ability). Hybrid (C57BL/6JIco x CBA/JIco) females were artificially inseminated at 13 h (control group) or 22 h (oocyte-aged group) after GnRH injection. Experimental (oocyte-aged group) F(0) females exhibited lower pregnancy rate, shortened gestation length, decreased litter size, higher perinatal death of their pups, and increased percentage of male offspring compared to control F(0) females. Postovulatory aging of oocytes was also associated with increased number of growth-retarded pups, delayed development of the righting reflex, and higher spontaneous motor activity and emotionality of F(1) offspring. Postovulatory aging of F(0) oocytes did not affect birth weight, weight gain during preweaning development, passive and active conditioned learning ability of F(1) offspring, or reproductive traits of F(1) females or developmental and behavior variables of F(2) offspring. 相似文献
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3.
Cynthia?A. Stanich Aurelia?R. Honerkamp-Smith Gregory?Garbès Putzel Christopher?S. Warth Andrea?K. Lamprecht Pritam Mandal Elizabeth Mann Thien-An?D. Hua Sarah?L. Keller 《Biophysical journal》2013,105(2):444-454
We investigate isothermal diffusion and growth of micron-scale liquid domains within membranes of free-floating giant unilamellar vesicles with diameters between 80 and 250 μm. Domains appear after a rapid temperature quench, when the membrane is cooled through a miscibility phase transition such that coexisting liquid phases form. In membranes quenched far from a miscibility critical point, circular domains nucleate and then progress within seconds to late stage coarsening in which domains grow via two mechanisms 1), collision and coalescence of liquid domains, and 2), Ostwald ripening. Both mechanisms are expected to yield the same growth exponent, α = 1/3, where domain radius grows as timeα. We measure α = 0.28 ± 0.05, in excellent agreement. In membranes close to a miscibility critical point, the two liquid phases in the membrane are bicontinuous. A quench near the critical composition results in rapid changes in morphology of elongated domains. In this case, we measure α = 0.50 ± 0.16, consistent with theory and simulation. 相似文献
4.
Tarô Adati Shinichi Kato Wataru Toriumi Kei Kawazu Wayan Susila Ketut Sumiartha Gede Suastika Dadang I Made Samudra 《Applied Entomology and Zoology》2013,48(2):113-118
The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest. 相似文献
5.
Rogerio Faustino Ribeiro Jr Felipe F. Potratz Brunella M. M. Pavan Ludimila Forechi Filipe Lugon Moulin Lima Jonaina Fiorim Aurelia Araujo Fernandes Dalton Valentim Vassallo Ivanita Stefanon 《PloS one》2013,8(1)
Carvedilol has beneficial effects on cardiac function in patients with heart failure but its effect on ovariectomy-induced myocardial contractile dysfunction remains unclear. Estrogen deficiency induces myocardial contractile dysfunction and increases cardiovascular disease risk in postmenopausal women. Our aim was to investigate whether carvedilol, a beta receptor blocker, would prevent ovariectomy-induced myocardial contractile dysfunction. Female rats (8 weeks old) that underwent bilateral ovariectomy were randomly assigned to receive daily treatment with carvedilol (OVX+CAR, 20 mg/kg), placebo (OVX) and SHAM for 58 days. Left ventricle papillary muscle was mounted for isometric tension recordings. The inotropic response to Ca2+ (0.62 to 3.75 mM) and isoproterenol (Iso 10−8 to 10−2 M) were assessed. Expression of calcium handling proteins was measured by western blot analysis. Carvedilol treatment in the OVX animals: prevented weight gain and slight hypertrophy, restored the reduced positive inotropic responses to Ca2+ and isoproterenol, prevented the reduction in SERCA2a expression, abolished the increase in superoxide anion production, normalized the increase in p22phox expression, and decreased serum angiotensin converting enzyme (ACE) activity. This study demonstrated that myocardial contractile dysfunction and SERCA2a down regulation were prevented by carvedilol treatment. Superoxide anion production and NADPH oxidase seem to be involved in this response. 相似文献
6.
Ismail Lafri Lionel Almeras Idir Bitam Aurelia Caputo Amina Yssouf Claire-Lise Forestier Arezki Izri Didier Raoult Philippe Parola 《PLoS neglected tropical diseases》2016,10(1)
Background
Phlebotomine sand flies are known to transmit Leishmania parasites, bacteria and viruses that affect humans and animals in many countries worldwide. Precise sand fly identification is essential to prevent phlebotomine-borne diseases. Over the past two decades, progress in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as an accurate tool for arthropod identification. The objective of the present study was to investigate the usefulness of MALDI-TOF MS as a tool for identifying field-caught phlebotomine.Methodology/Principal Findings
Sand flies were captured in four sites in north Algeria. A subset was morphologically and genetically identified. Six species were found in these areas and a total of 28 stored frozen specimens were used for the creation of the reference spectrum database. The relevance of this original method for sand fly identification was validated by two successive blind tests including the morphological identification of 80 new specimens which were stored at -80°C, and 292 unknown specimens, including engorged specimens, which were preserved under different conditions. Intra-species reproducibility and inter-species specificity of the protein profiles were obtained, allowing us to distinguish specimens at the gender level. Querying of the sand fly database using the MS spectra from the blind test groups revealed concordant results between morphological and MALDI-TOF MS identification. However, MS identification results were less efficient for specimens which were engorged or stored in alcohol. Identification of 362 phlebotomine sand flies, captured at four Algerian sites, by MALDI-TOF MS, revealed that the subgenus Larroussius was predominant at all the study sites, except for in M’sila where P. (Phlebotomus) papatasi was the only sand fly species detected.Conclusion
The present study highlights the application of MALDI-TOF MS for monitoring sand fly fauna captured in the field. The low cost, reliability and rapidity of MALDI-TOF MS analyses opens up new ways in the management of phlebotomine sand fly-borne diseases. 相似文献7.
Gerold Bepler Uwe Zeymer Samira Mahmoud Gary Fiskum Edmund Palaszynski Martin Rotsch James Willey Aurelia Koros Frank Cuttitta Terry W. Moody 《Peptides》1988,9(6):1367-1372
Human small cell lung cancer (SCLC) produces and secretes BN/GRP (bombesin/gastrin releasing peptide). Because BN stimulates the growth of SCLC cells and these cells have receptors for BN-like peptides, it is important to define agents which disrupt this self-promoting autocrine growth cycle. Here, substance P analogues were evaluated as BN receptor antagonists using SCLC cell lines. (D-Arg1, D-Pro2, D-Trp7,9, Leu11) substance P [(APTTL)SP] was one of the more potent analogues tested in inhibiting BN-like peptide receptor binding with an IC50 value of 1 μM. Micromolar concentrations of (APTTL)SP antagonized BN receptor mediated elevation of cytosolic Ca2+ levels and decreased the colony formation in soft agarose. These data suggest that SP analogues function as SCLC BN receptor antagonists and may be useful in disrupting the autocrine growth function of BN-like peptides. 相似文献
8.
Tang RS Schickli JH MacPhail M Fernandes F Bicha L Spaete J Fouchier RA Osterhaus AD Spaete R Haller AA 《Journal of virology》2003,77(20):10819-10828
9.
Howell KP Skipwith A Galione A Eckberg WR 《Biochemical and biophysical research communications》2003,307(1):47-51
Egg activation in all animals evidently requires the synthesis of inositol 1,4,5-trisphosphate (InsP(3)) from phosphatidylinositol 4,5-bisphosphate (PIP(2)) by phospholipase C (PLC). Depending on the organism, InsP(3) elicits either calcium oscillations or a single wave, which in turn initiates development. A soluble component in boar sperm that activates mammalian eggs has been suggested to be a PLC isoform. We tested this hypothesis in vitro using egg microsomes of Chaetopterus. Boar sperm factor elicited Ca(2+) release from the microsomes by an InsP(3)-dependent mechanism. The PLC inhibitor U-73122, but not its inactive analog U-73343, blocked the response to sperm factor but not to InsP(3). U-73122 also inhibited the activation of fertilized and parthenogenetic eggs. Chaetopterus sperm also contained a similar activity. These results strongly support the hypothesis that sperm PLCs are ubiquitous mediators of egg activation at fertilization. 相似文献
10.
This study aims to compare the effect of early and late onset administration of oral antioxidants on number and quality of oocytes retrieved from aged mice after exogenous ovarian stimulation. Control hybrid females were fed a standard diet supplemented or not supplemented with pharmacological doses of vitamins C and E either from the first day of weaning or from the age of 32 weeks until they were autopsied at the age 40-42, 50-52, or 57-62 weeks after exogenous ovarian stimulation. Analysis of chromosomal distribution, DNA organization and cellular morphology was performed in ovulated cumulus-enclosed and -free oocytes, ovarian non-germinal vesicle oocytes enclosed by or free of mucous cumulus cells and in vitro-matured ovarian germinal-vesicle oocytes. Both early and late onset administration of oral antioxidants counteracted the negative effects of female aging on number of ovarian oocytes and total percentage of oocytes retrieved from oviducts and ovaries exhibiting a normal distribution of chromosomes in the metaphase-II plate and/or morphological traits of apoptosis. Although both early and late onset administration of oral antioxidants can counteract the negative effects of female aging on number and quality of oocytes, transference of these results to human beings should be made with caution because of the potential side effects of high doses of vitamins on reproductive function as well as many other undesirable systemic disorders. 相似文献