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51.
The stimulus determinants of pseudopregnancy were examined by mating female rats to castrated males maintained on estradiol benzoate (EB) or testosterone propionate (TP), or to intact males. Females were mated for five intromissions (5I), one ejaculatory series (1E), or three ejaculatory series (3E). Copulatory behavior was quite similar for males of all groups. Overall, females that copulated with EB males became pseudopregnant significantly less often than those females mated to TP or intact males. The amount of copulation (5I vs. 1E vs. 3E) received by females from functionally intact males influenced their probability of becoming pseudopregnant or pregnant. EB males had significantly lower body, penile, and seminal vesicle weights in addition to a greatly reduced complement of penile spines than either TP or intact males; adrenal weights did not differ. TP and intact males did not differ on any weight measure. These results indicate that some factor influenced by male hormonal status, possibly penile morphology, plays a role in the initiation of the functional luteal phase in laboratory rats.  相似文献   
52.
Objectives To compare the systemic exposure for intranasal mometasone furoate (MF) and fluticasone propionate (FP) aqueous nasal sprays (ANS) in terms of serum and urinary cortisol parameters and plasma pharmacokinetics.Methods Twelve healthy subjects completed this three-way, cross-over study. They received FPANS (50 g/spray), MFANS (50 g/spray) or placebo ANS, eight sprays per nostril every 8 h for 4 days. Cortisol measurements were made at baseline and day 4. FP and MF plasma concentrations were also measured on day 4.Results MFANS produced similar mean plasma AUC (123 pmol/l h) to FPANS (112 pmol/l h). Despite the use of high doses, necessary to generate adequate pharmacokinetic data, only minor reductions in cortisol parameters were found, with no difference between FPANS and MFANS.Conclusions FP and MF have similar and very low systemic bioavailability when administered intranasally using a high-dose regimen. It is therefore unlikely that therapeutic doses of intranasal FP or MF will produce dissimilar or significant degrees of systemic exposure or systemic effects.  相似文献   
53.
Developmental toxicity of estrogenic chemicals on rodents and other species   总被引:2,自引:0,他引:2  
ABSTRACT  Antenatal sex-hormone exposure induces lesions in mouse reproductive organs, which are similar to those in humans exposed in utero to a synthetic estrogen, diethylstilbestrol. The developing organisms including rodents, fish and amphibians are particularly sensitive to exposure to estrogenic chemicals during a critical window. Exposure to estrogens during the critical period induces long-term changes in reproductive as well as non-reproductive organs, including persistent molecular alterations. The antenatal mouse model can be utilized as an indicator of possible long-term consequences of exposure to exogenous estrogenic compounds including possible environmental endocrine disrupters. Many chemicals released into the environment potentially disrupt the endocrine system in wildlife and humans, some of which exhibit estrogenic activity by binding to the estrogen receptors. Estrogen responsive genes, therefore, need to be identified to understand the molecular basis of estrogenic actions. In order to understand molecular mechanisms of estrogenic chemicals on developing organisms, we are identifying estrogen responsive genes using cDNA microarray, quantitative RT-PCR, and differential display methods, and genes related to the estrogen-independent vaginal changes in mice induced by estrogens during the critical window. In this review, discussion of our own findings related to endocrine distuptor issue will be provided.  相似文献   
54.
OBJECTIVES: The aims of the study were to determine: 1) how mucociliary activity in acute bacterial rhinosinusitis is affected; 2) how this activity is changed by therapy; 3) the effects of topical agents on mucociliary clearance, and 4) the most appropriate topical agent(s) to be used in the therapy of sinusitis. STUDY DESIGN: Five groups of patients with acute bacterial rhinosinusitis were studied prospectively. METHODS: All patients had 500 mg oral amoxicillin and 125 mg oral clavulanic acid preparations given three times daily for 3 weeks. According to the topical agent applications, these groups included: group I (n = 12), no topical treatment was given; group II (n = 14), two puffs for each nostril once daily of 50 microg/100 mL fluticasone propionate was given; group III (n = 9), one puff for each nostril three times daily of 0.05% oxymetazoline was given; group IV (n =12), 3% sodium chloride (NaCl) (buffered to pH 6.5-7 at room temperature) was given; and group V (n =13), 10-mL solutions of 0.9% NaCl (buffered to pH 6.5--7 at room temperature) were given for nasal irrigations three times daily. All patients had medication for 3 weeks and were controlled each week. The saccharin method was used to measure nasal mucociliary clearance. To investigate the early effects of the topical agents for groups II to V, an additional test was repeated 20 minutes after the basal mucociliary clearance recordings. The test was repeated in the first, second, and third weeks of the treatment. RESULTS: The mucociliary clearance was significantly slower in the acute bacterial rhinosinusitis group than in the control group. There was no significant difference between the basal mucociliary clearance and the 20th minute mucociliary clearance of the fluticasone propionate and 0.9% NaCl solution groups. The mean values of the basal and the 20 minute's mucociliary clearance of the oxymetazoline group were 24.72 +/- 6.16 and 15.5 +/- 7.45 minutes, respectively, which were statistically significant. The mean values of the basal and the 20th minute mucociliary clearance of the 3% NaCl solution groups were 19.45 +/- 9.35 and 15.45 +/- 8.20 minutes, respectively, which were also statistically significant. In the first group (without topical treatment), the basal mucociliary clearance became significantly shorter after the second week of treatment. In the first and second weeks of the treatment of the oxymetazoline group, the mucociliary clearance did not change significantly, but after the third week the mucociliary clearance was significantly shorter. In the 3% NaCl solution group, significant improvement began from the first week and continued through the third week. Comparing the basal and the third weeks' mucociliary clearance values among the groups, the oxymetazoline and 3% NaCl solution groups revealed more significant improvement than the other groups, but this improvement was not different from the improvement of group I. There was still a statistically significant difference in the mucociliary clearance of the post-treatment sinusitis groups from the control group. CONCLUSIONS: The oxymetazoline and 3% NaCl solution groups seemed to be more effective in mucociliary clearance, but there was no significant difference in improvement among the groups. The improvement of acute bacterial rhinosinusitis takes more than 3 weeks, according to the mucociliary clearance values of the groups.  相似文献   
55.
AIMS: To measure and compare the systemic bioavailability of fluticasone propionate aqueous nasal spray and a new nasal drop formulation, using a sensitive analytical method and high dose regimen. METHODS: Volunteers received four 800 microg doses of fluticasone propionate as a nasal spray or drops over 2 days, separated by an 8 h dose interval. On day 2, blood samples were collected for assay of fluticasone propionate plasma concentrations. RESULTS: The mean systemic exposure, for both formulations was 8.5 pg x ml(-1) x h (drops) and 67.5 pg x ml(-1) x h (spray). Mean absolute bioavailabilities were estimated to be 0.06% (drops) and 0.51% (spray), by reference to historical intravenous data. CONCLUSIONS: Both formulations exhibited low systemic bioavailability, even at 12 times the normal daily dose. The bioavailability from the nasal drops was approximately eight times lower than from the nasal spray.  相似文献   
56.
目的:比较吸入沙美特罗/丙酸氟替卡松(SM/FP)治疗稳定期慢性阻塞性肺疾病(COPD)的疗效.方法:采用随机平行对照实验方法,将60例29~76岁肺功能Ⅱ~Ⅲ级的COPD患者随机分为治疗组(30例)和对照组(30例).治疗组患者吸入SM/FP(50μg/250μg);对照组常规治疗.比较分析2组患者肺功能及住院次数变化.结果:经6个月的治疗,治疗组与对照组肺功能变化差异有统计学意义(P<0.05).治疗组半年住院次数(3人次)少于对照组(7人次).结论:长期联合吸入糖皮质激素和β2-受体激动剂治疗稳定期COPD的疗效优于非吸人治疗.  相似文献   
57.
蓖麻毒素及其SPDP修饰物对小鼠肝脏GSH含量的影响   总被引:4,自引:0,他引:4  
赵英  王文学  董巨莹  蒋宁 《医学争鸣》1999,20(10):838-840
目的:观察麻毒素(RT)修饰前后对小鼠肝脏毒性的影响。方法:RT用3-(2-吡啶二巯基)丙酸N-羟基琥珀酰亚胺酯中(SPDP)--一种异型双功能交联剂,进行化学修饰,自下而上的SPDP衍生物(PDP-R),测定两者在不同剂量和时间对小鼠肝脏还原型谷胱甘肽(GSH)含量的影响,以比较两者的毒性差别,结果:随着中毒剂量的增加和时间的延长,两者与可使小鼠肝脏GSH含量下降,但RT组下降程度较PDP-R  相似文献   
58.
BACKGROUND: Previous studies comparing the corticosteroids fluticasone propionate (FP) and budesonide (BUD) in both perennial and seasonal rhinitis have shown no consistent difference between treatments. However, the therapeutic outcomes may have been influenced by study design. OBJECTIVE: To compare the effect of FP aqueous nasal spray (ANS; 200 microg/day) with BUD reservoir powder device (RPD; 200 microg/day) on rhinitis symptoms, productivity loss and device preference in patients with perennial rhinitis. METHODS: After a 2-week run-in period, 440 patients were randomized to receive either FPANS, BUD RPD or matched placebo (ANS or RPD) for 8 weeks, followed by an open-label 4-week follow-up treatment with FPANS. Patients completed diary card visual analogue scores for nasal symptoms, and questionnaires on satisfaction with the treatment and preferred choice of device. RESULTS: During weeks 1-4, the visual analogue total nasal symptom scores (VATNS) in the FPANS group were significantly lower than scores in the BUD RPD group (mean difference = -17.8; 95% CI = -34.4, -1.3; P = 0.036). FPANS also significantly reduced the VATNS compared with the ANS placebo at all time-points assessed (P < or = 0.005). BUD RPD did not significantly differ from the RPD placebo at weeks 5-8 (P = 0.167), or the ANS placebo at any time-point (P < or = 0.151). Over the 8-week treatment period FPANS was significantly more effective than BUD RPD at reducing sneezing (mean difference = -4.4; 95% CI = -8.6, -0.3; P = 0.036) and nasal itching (mean difference = -5.3; 95% CI = -9.9, -0.8; P = 0.022), and was significantly superior to the ANS placebo for all symptoms assessed at weeks 1-4 and 1-8 (P < 0.016). At the same time-points BUD RPD was no better at alleviating nasal itching than the RPD placebo (P < or = 0.306), and compared with the ANS placebo, significantly reduced only one symptom; nasal blockage (P < or = 0.016). After 8 weeks of treatment, patients preferred the ANS device to the RPD (P < 0.001), and at 12 weeks a significantly greater number of patients were satisfied with FPANS treatment compared with BUD RPD (P = 0.0019) or the respective placebos (P = 0.0001). CONCLUSION: FPANS and BUD RPD are effective therapies with a good safety profile for the treatment of perennial rhinitis but, in this direct placebo-controlled comparison, FPANS was more efficacious than BUD RPD, and the patients preferred the ANS device to the RPD.  相似文献   
59.
This is the 1st case report of allergic contact dermatitis from a perinone-type plastic dye, C.I. Solvent Orange 60, used in the earpieces of spectacle frames. Sensitization of this dye was confirmed by patch tests and chemical analysis of the causative earpieces and coloring agents. Solvent Orange 60 is suspected of being the contact allergen in at least 2 other Japanese cases of spectacle earpiece dermatitis, and provoked strong reactions on sensitized individuals. Its use in products that are applied on human skin for a prolonged period of time, such as spectacle frames or hearing aids, would best be avoided.  相似文献   
60.
Inhaled corticosteroids (ICS) are preferred drugs for the long-term treatment of all severities of asthma in children. However, data about the safety of ICS in infants is lacking. So, it is essential to do further clinical studies to examine the safety and efficacy of ICS in this population. In this study, the effects of nebulized budesonide and nebulized fluticasone propionate suspensions on hypothalamic–pituitary–adrenal axis is examined in infants with recurrent or persistent wheeze. Thirty-one children aged 6–24 months admitted to our hospital between January and December 2005 with symptoms of recurrent or persistent wheeze were included in the study. The patients were randomly allocated to receive 0.25 mg BUD or 0.25 mg fluticasone propionate twice daily for 6 wk and half dose for another 6 wk with a jet nebulizer at home. Blood samples for basal cortisol concentration, adrenocarticotropic hormone, glucose, HbA1c and electrolytes were obtained at the beginning and at the end of the study. Adrenal function assessment was based on changes in cosyntropin-stimulated plasma cortisol levels. The study was completed with 31 patients, 16 of whom received BUD and 15 FP. All patients except one had plasma cortisol concentrations above 500 nmol/l (18 μg/dl) or had an incremental rise in cortisol of >200 nmol/l after stimulation. Although nebulized steroids seem to be safe in infancy, we recommend that adrenal functions should be tested periodically during long-term treatment with nebulized steroids.  相似文献   
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