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Esko Laes Pentti Lehtovirta Dave Weintraub Tapani Pyörälä Tapani Luukkainen 《Contraception》1975,11(3):289-295
The Copper-T-200 (CuT-200) was inserted after delivery at term in 197 women on the day preceding discharge from the hospital. The majority of the insertions were done on day 5 or 6 after delivery. Every subject in the study was followed more than 12 months. The insertions were well tolerated; no perforations or serious side effects occurred. During the first year of use, only 9 infections were recorded. The first segment pregnancy rate (7.2) and expulsion rate (14.8) were significantly higher and the continuation rate, 69.5, lower than that obtained with the same device inserted in postmenstrum women. The expulsions were mainly partial (11.1), and were discovered during the first and second months postpartum. The postpartum insertions were found to be safe and well accepted. The high pregnancy and expulsion rates make the CuT-200 an unsuitable IUD in postpartum programs where follow-up is not adequate and early removals of partially expelled or displaced devices is not possible. 相似文献
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BACKGROUND: A cross-talk between 1alpha,25-dihydroxyvitamin D(3) [1alpha,25-(OH)(2)D(3)] and 5alpha-dihydrotestosterone (DHT) in the growth inhibition has been demonstrated, but the mechanism is unknown. METHODS: The expression of 25-hydroxyvitamin D(3) 24-hydroxylase (24-hydroxylase) was measured using a real-time quantitative RT-PCR assay and the catabolism of 1alpha,25-(OH)(2)D(3) was measured using a radioreceptor assay. RESULTS: Real-time RT-PCR showed that DHT at 1-100 nM significantly inhibited 1alpha,25-(OH)(2)D(3)-induced expression of 24-hydroxylase in LNCaP cells. Furthermore, the catabolism of 1alpha,25-(OH)(2)D(3) was decreased by 10 nM DHT. An androgen receptor (AR) antagonist, Casodex antagonized the DHT effect, whereas an AR agonist (due to the mutant AR in LNCaP cells) hydroxyflutamide did not. CONCLUSIONS: We demonstrated, for the first time, that DHT reduces the ability of 1alpha,25-(OH)(2)D(3) to induce 24-hydroxylase expression. Our results not only support the earlier finding of a cross-talk between androgen and vitamin D in human prostate cancer cells but also provide a possible mechanism how androgen and vitamin D signaling pathways may interact. 相似文献
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Bone structure and volumetric density in young adults born prematurely: a peripheral quantitative computed tomography study 总被引:1,自引:0,他引:1
Prematurity is known to be associated with reduced bone mineral density (BMD) in childhood, but whether this condition has long-term detrimental consequences on adult bone structure is not known. In this study, we measured with peripheral quantitative computed tomography (pQCT) the total bone cross-sectional area, cortical area and wall thickness, cortical and trabecular density, and a density-weighed polar section modulus as a bone strength index (BSI) at distal and shaft sites of right radius and tibia in a group of 40 prematurely born, otherwise normally developed and healthy young adults (17 women and 23 men, aged 18 to 27 years) and compared their data to corresponding data obtained from a group of 42 control subjects born term (20 women and 22 men, aged 18 to 28 years). Body height and weight were similar in both groups, but the preterm group had significantly lower BSI values at distal sites of tibia (approximately -16%) and radius (approximately -13%) and at tibial shaft (approximately -11%) as compared to control group. In the weight-bearing tibia, BMC was lower and the lower BSI values were mainly due to smaller total bone cross-sectional area. For unknown reason, this prematurity-associated detrimental effect seemed to concern more men than women. In contrast, prematurity was not associated with volumetric trabecular and cortical densities at any measured bone site while the typical sex differences in bone density were observed. We conclude that prematurity is associated with somewhat smaller cross-sectional bone dimensions in terms of body size in young adulthood. Due to the cross-sectional design, this study could not reveal specific reasons but they may pertain to nutrition during the neonatal period and living habits in general. 相似文献
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Background
The results in an earlier study with 2–5-year-old children indicated that, in comparison with conventional prevention, a risk-based prevention programme was effective in reducing dental caries in a low-caries community. The aim of the present study was to examine the clinical and economic findings seven years after the cessation of the targeted programme, from the perspective of public health care. 相似文献69.
Kuttila S Kuttila M Le Bell Y Alanen P Suonpää J 《International journal of audiology》2005,44(3):164-170
This study aimed to reveal in general population the prevalence, associations, and statistical model of recurrent tinnitus by means of a mailed questionnaire. The study sample consisted of 1720 randomly selected adults who were classified into three subgroups: recurrent (once a month or more often), occasional (less often than once a month), and no tinnitus. According to age and gender standardized prevalence, recurrent tinnitus was reported in 15% of the sample. It was statistically highly significantly associated with earache, fullness of ears shoulder pain, the 25-years age group, and visits to a physician. The strongest predictor of recurrent tinnitus was fullness of ears followed by earache, shoulder ache, and temporomandibular disorder pain. We conclude that recurrent tinnitus seems to be quite common in adults and associated with earache and fullness of ears In patients with tinnitus without clinical findings, the examination of the stomatognathic system and cervical spine is recommended. 相似文献
70.
Dietary linolenic acid and adjusted QT and JT intervals in the National Heart, Lung, and Blood Institute Family Heart study 总被引:2,自引:0,他引:2
Djoussé L Rautaharju PM Hopkins PN Whitsel EA Arnett DK Eckfeldt JH Province MA Ellison RC;Investigators of the NHLBI Family Heart Study 《Journal of the American College of Cardiology》2005,45(10):1716-1722
OBJECTIVES: The goal of this study was to examine whether higher consumption of total linolenic acid was associated with rate-adjusted QT and JT intervals (QTrr and JTrr, respectively). BACKGROUND: Higher intake of fish omega-3 fatty acids and plant omega-3 such as alpha-linolenic acid is associated with lower risk of myocardial infarction. While long-chain omega-3 can inhibit ventricular arrhythmia, it is not known whether alpha-linolenic acid influences ventricular repolarization. METHODS: We studied 3,642 subjects from the National Heart, Lung, and Blood Institute Family Heart study who were free of myocardial infarction, left ventricular hypertrophy, pacemaker, and with QRS <120 ms. We used the 95th percentile of the gender-specific distribution of QTrr and JTrr to define abnormally prolonged repolarization. Within each gender, we created age- and energy-adjusted tertiles of linolenic acid and used regression models for analyses. RESULTS: Mean age was 50 years, and average intake of total linolenic acid was 0.74 g/day. There was an inverse association between consumption of linolenic acid and QTrr and JTrr (p for trend 0.001 and 0.0005, respectively). From the lowest (reference) to the highest gender-, age-, and energy-adjusted tertile of linolenic acid, multivariable adjusted odds ratios for prolonged QTrr were 1.0, 0.74 (95% confidence interval [CI] 0.57 to 0.96), and 0.59 (95% CI 0.44 to 0.77), respectively (p for trend 0.0003). Corresponding values for JTrr were 1.0, 0.73 (95% CI 0.52 to 1.03), and 0.59 (95% CI 0.40 to 0.87), respectively (p for trend 0.009). Exclusion of subjects taking drugs known to influence QT did not influence this association. CONCLUSIONS: Higher intake of dietary linolenic acid might be associated with a reduced risk of abnormally prolonged repolarization in men and women. 相似文献