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31.
Tasdemir Murat; Tasdemir Isik; Kodama Hideya; Tanaka Toshinobu 《Human reproduction (Oxford, England)》1993,8(12):2102-2107
To evaluate the possible effect of pentoxifylline on the acrosomereaction (AR) and its correlation with in-vitro fertilization(IVF), sperm samples obtained from 51 patients who underwentIVF treatment were studied. Acrosome reactions were evaluatedas spontaneous, pentoxifylline-treated and calcium ionophore(A23187) induced, before and after treatment. The correlationof AR with fertilization in vitro in spermatozoa pre-treatedwith pentoxifylline was sought. In cases with failure or verylow fertilization rate (10%) in their previous trials, spermatozoaafter swim-up were treated before insemination. Spontaneousacrosome loss remained low even after treatment (mean ±SD: 8.18 ± 1.74%). Response to A23187 was enhanced significantly(P < 0.001) by pre-treatment with pentoxifylline in 33 controlcases (group A) in which fertilization in vitro was previouslysuccessful without this treatment. Patients with at least twoepisodes of failed fertilization were divided into two groups.In 11 cases (group B), the IVF rate was improved significantly(P < 0.001) by the treatment. This was not observed in sevencases (group C) in which the treatment induced no increase inIVF rate. We achieved nine (27.3%) pregnancies in group A andfive (45.4%) pregnancies in group B. This study demonstratedthat pentoxifylline enhanced A23187 induced the acrosome reactionand this effect was correlated with improvement in IVF rate. 相似文献
32.
33.
The turnover rates of adrenaline in the medial preoptic area and mediobasal hypothalamus, areas which, respectively, include the cell bodies and terminals of luteinizing hormone-releasing hormone neurons, have been measured in female rats on pro-oestrus, the day of the preovulatory surge of luteinizing hormone, and on dioestrus, the preceding day. A rise in the rate of turnover was found in the medial preoptic area coinciding with the surge of luteinizing hormone in the late afternoon of pro-oestrus; the rate of turnover at this time was higher than at the same time on dioestrus. No changes in turnover rate were found in the mediobasal hypothalamus within either of these days.The results indicate that the adrenaline-containing projections to the preoptic area may be actively involved in the production of the spontaneous preovulatory surge of luteinizing hormone in rats. 相似文献
34.
BACKGROUND: Food atopy patch tests (APTs) are considered a useful tool for the diagnosis of food allergy. Hypersensitivity to peanuts has not been investigated by means of APTs so far. METHODS: APTs and skin prick tests (SPTs) with peanuts were performed in 136 atopic dermatitis (AD) patients. Relevance of positive and negative responses to these tests was assessed by repeated open challenges with peanuts. RESULTS: Nine percent of our AD patients reacted to the challenge. Positive responses to APTs were recorded in 19% of the patients, whereas in 12% positive SPTs were observed. APTs were more frequently positive in subjects with eczematous responses after challenge with respect to those with urticarial reactions. SPT reactivity proved to be higher in patients above 12 years of age, whereas APT positivity was more frequent in children under 6 years. APT sensitivity proved significantly higher than SPT sensitivity, in particular in children under 12 years of age. On the contrary, SPT specificity and positive predictive value were significantly higher with respect to those of APT in the age group of subjects under 6 years of age. CONCLUSIONS: Our data suggest that APTs with peanuts may represent a useful integration to standard testing modalities employed for the diagnosis of peanut allergy in AD patients. 相似文献
35.
The morphogenesis of testicular degeneration induced in rats by orally administered 2,5-hexanedione 总被引:5,自引:0,他引:5
The neurotoxic hexacarbon 2,5-hexanedione (2,5-HD) produces testicular atrophy in experimental animals. To examine the morphogenesis of the testicular lesion, 1.0% 2,5-HD was provided in the drinking water of adult F-344 rats for up to 6 weeks. After 3 weeks of administration, there were occasional large vacuoles in the basal region of the germinal epithelium. At 4 weeks, these vacuoles were much larger and more numerous; electron microscopy demonstrated that they were derived from the smooth endoplasmic reticulum. The vacuoles were preferentially associated with stages 12, 13, 14, and 1 of the spermatogenic cycle. Additionally, at 4 weeks there was a significant decrease in the number of tubules in stages 7 and 13, and a concomitant increase in the percentage of tubules in stages 3, 5, and 6. By Week 5, most Golgi-phase and cap-phase spermatids were visibly affected, showing margination of nuclear chromatin, and were becoming dissociated from Sertoli cells. Frequent multinucleated giant cells were seen and electron microscopy of these cells suggested that they were derived from fused spermatocytes or spermatids. After 6 weeks, fewer giant cells were present, most tubules contained cellular debris, and many showed empty lumina encircled by a thin ring of cytoplasm near the basement membrane. Interstitial tissue appeared unaffected. These studies indicate that the Sertoli cell is probably an initial target for 2,5-HD action in the testis. 相似文献
36.
Evidence was presented for a glutamate agonistic effect of L-proline which promotes K+-based spreading depressions (SD) in chick retinas at relatively high concentrations (5 mM), in addition to an antagonistic effect which inhibits glutamate-based SDs at lower (2 mM) concentrations. Together these effects explain the observed biphasic effect of L-proline on the incidence of SD in the retina. 相似文献
37.
Isolation and characterization of entomopox virions from virus-containing inclusions of Amsacta moorei (Lepidoptera: Arctiidae) 总被引:2,自引:0,他引:2
Preparations of Amsacta moorei entomopox virions were obtained from virus-containing inclusions (VCI) by using a carbonate-thioglycolate solution (pH 10.7–11.5). The virions possessed a uniform coat (“halo”) surrounding the viral envelope and exhibited an RNA polymerase activity. The “halo” could be removed by prolonged exposure to the carbonate-thioglycolate solution. Virions obtained by this treatment, however, possessed low infectivity and no detectable RNA polymerase activity. Removal of the “halo” by trypsin resulted in virions which possessed RNA polymerase activity and relatively high infectivity.Preparations of particles with and without the “halo” were similar in percent DNA, protein per OD260, number of particles per OD260, and RNA polymerase activity. Particles without the “halo,” however, were less dense (1.262 g/cm3) in CsCl than those with the “halo” (1.282 g/cm3) and 15–45 times more infective.Parallel studies of “nonhaloed” Amsacta virions (trypsin-treated) and vaccinia virions showed that both viruses contained similar amounts of protein per OD260, but Amsacta virions contained only 36% of the DNA found in vaccinia. 相似文献
38.
Krug N Hohlfeld JM Geldmacher H Larbig M Heermann R Lavallee N Nguyen DT Petzold U Hermann R 《Allergy》2005,60(3):354-359
BACKGROUND: Loteprednol etabonate (LE) is a novel soft steroid that was designed to improve the benefit/risk ratio of topical corticosteroid therapy. This study assesses the clinical efficacy and safety of three different doses of LE nasal spray in seasonal allergic rhinitis (SAR). METHODS: In this single-center, double-blind, placebo-controlled, parallel-group trial 165 subjects with SAR to grass pollen received daily single doses of either 100, 200, 400 microg LE nasal spray, or placebo for 14 days. The patients underwent three 4-h allergen challenges with grass pollen in an environmental exposure unit at a screening visit (baseline) and on days 7 and 14 of treatment. Standardized nasal symptom scores were obtained every 20 min. Nasal flow, nasal secretions, and FEV(1) were measured every hour during allergen challenges. RESULTS: After 14 days of treatment, patients who received 400 microg LE had significantly lower total nasal symptom scores compared with those receiving placebo (P = 0.007). LE400 reduced rhinorrhea, nasal congestion, nasal itching, the amount of nasal secretions, and improved nasal flow as compared with placebo (P < 0.05). LE100 and LE200 were not significantly different from placebo. All treatments were well tolerated. CONCLUSIONS: Loteprednol 400 microg once daily is superior to placebo and the only effective dose tested in improving nasal symptoms and objective parameters in patients with SAR. 相似文献
39.
We studied the effect and onset of action of fluticasone propionate aqueous nasal spray (FPANS) on mediator release and eosinophil accumulation in nasal secretions and on nasal symptoms of patients with seasonal allergic rhinitis after nasal allergen challenge (NAC). At the end of the pollen season, 28 patients were randomized in a double-blind and crossover design to receive 7 days' treatment with FPANS (200 μg, once daily) and matching placebo. NACs were performed before and at 6 h and 1. 2. 3. and 7 days during treatment with FPANS or placebo. Nasal secretions were collected for a quantitative determination of mediators and eosinophil count before and 5 min after each challenge. Nasal symptoms were assessed by scales grading the severity of symptoms at the same time. Results showed that for mediator concentrations there was a significant decrease of leukotriene C4 (P<0.001) at 7 days after the first administration of FPANS as compared to placebo. Two days after FPANS. both eosinophil counts and eosinophil cationic protein (ECP) concentrations were lower than those of placebo (eosinophils; f=0.032; ECP; F=0.038). The onset became even more important at day 7 (eosinophils; P=0.001; ECP; P=0.009) during the FPANS treatment period. For the subjective nasal symptoms, a significant reduction of symptom scores for nasal obstruction occurred also at day 3 (F=0.017) and for sneezing at day 7 (f=0.003). There was not yet any significant improvement of the objective nasal airway resistance after the different NACs during the study period. In conclusion, this study demonstrated that topical fluticasone propionate is effective in the treatment of mucosal inflammation induced by NAC. For optimal control of nasal symptoms induced by repeated maximal allergen challenges, a treatment period of more than 1 week is required. 相似文献
40.
Factors that affect genetic interaction during mixed infection with temperature-sensitive mutants of simian rotavirus SA11 总被引:3,自引:0,他引:3
R F Ramig 《Virology》1983,127(1):91-99
A number of factors that affect genetic interaction during mixed infection with temperature-sensitive mutants of simian rotavirus SA11 have been examined. (1) Statistical analyses of recombination frequency (RF) indicated that (a) the variability noted in RF was not related to variations in experimental conditions and (b) a linear map of the mutations could not be drawn. (2) The wild phenotype of recombinant progeny was stable on passage. (3) Aggregates of progeny virus or heterozygous progeny virus particles did not contribute significantly to the observed RF. (4) RF increased in parallel with multiplicity of infection. (5) A maximal, or near maximal, RF was obtained at the earliest time significant recombinants could be detected. (6) Recombination was efficient at nonpermissive temperature. (7) Complementation did not occur or was inefficient. (8) Mutants from all recombination groups interfered with the growth of wild-type virus at both permissive and nonpermissive temperatures. 相似文献