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Liesbeth Vandenput Fernand Labrie Dan Mellstr?m Charlotte Swanson Thomas Knutsson Ralph Peeker Osten Ljunggren Eric Orwoll Anna L Eriksson Jan-Erik Damber Claes Ohlsson 《Journal of bone and mineral research》2007,22(2):220-227
Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men. 相似文献
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复合式听写比听力选择题更强调语言综合运用能力。全面打好语言基本功是提高听写能力的重要途径。但听写训练具有自身的科学性和技巧性,多练加巧练可以取得事半功倍的成效。 相似文献
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刘伯宁 《中国实用妇科与产科杂志》2006,22(5):338-339
卵巢肿瘤合并副肿瘤性综合征(ovarian tumor associated with paraneoplastic syndrome)并非罕见,但由于此综合征往往先于肿瘤出现,而因肿瘤病灶小或隐匿不易被发现,常被临床医师所忽略,导致肿瘤未能得到及时诊断和治疗."paraneoplastic syndrome"一词有译为副肿瘤性综合征、副肿瘤综合征、副癌综合征、肿瘤外综合征者.此综合征为肿瘤患者的一种复合症状,该症状不能用肿瘤本身或肿瘤转移来解释.现按主要受累系统的几种综合征简介如下,以加强临床医师对卵巢肿瘤合并副肿瘤性综合征特点的认识,减少误诊、误治。 相似文献
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Chuan-Bin Guo Nian-Hui Cui Guang-Yan Yu Ding-Xin Liu Shu-Cong Meng Qing Song 《Journal of oral and maxillofacial surgery》2003,61(8):909-912
PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs. 相似文献
90.
刘小军 《四川省卫生管理干部学院学报》2004,23(4):313-314
重组α-2b干扰素是具有抗病毒和免疫调节作用的生物学调节活性物质。近年来,国外文献报道α-2b干扰素治疗慢性乙型病毒性肝炎(CAH—B)取得较好效果。特别是基因工程问世,使大量的高纯度干扰素应用于临床。现对48例慢性乙肝患者使用干扰素后的不良反应的观察与护理,报道如下。 相似文献