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1.
Hyperandrogenism in adolescent girls can be a troubling problem because of the difficulty in establishing a diagnosis and in prescribing appropriate therapy. Androgen excess in adolescent patients encompasses a spectrum of clinical presentations, including acne, hirsutism, oligomenorrhea, amenorrhea, virilism, and ovarian cysts. Androgen excess is a clinical and chemical feature of idiopathic hirsutism, late-onset forms of congenital adrenal hyperplasia, and polycystic ovarian disease; in some cases, functional hyperandrogenism is discussed. We recommend screening for hyperandrogenism by measuring blood levels of testosterone, dehydroepiandrosterone sulfate, and delta 4-androstenedione, while others propose a first dexamethasone suppression test for evaluation of free testosterone, dehydroepiandrosterone sulfate, and cortisol. Treatment will be chosen according to particular symptoms such as acne, hirsutism, obesity, or oligomenorrhea.  相似文献   
2.
Androgen insensitivity syndromes are X-linked disorders. Restriction fragment length polymorphism analysis of the androgen receptor gene showed that deletions were infrequent. Some mutations have been described. In these conditions, in high-risk family, carrier diagnosis is impossible unless identification of mutations is made. It is thus necessary to detect androgen receptor gene polymorphism in order to differentiate the two maternal X chromosomes. Two androgen receptor gene polymorphisms have been reported (Hind III and exon 1). In this study we analyzed these two gene polymorphisms to detect carriers in at-risk families. The combined results of the two analyses allowed us to detect carriers in 45% of the studied families. In two families the prenatal diagnosis of androgen insensitivity syndrome was performed.  相似文献   
3.
It has been suggested that rate of estrogen formation was higher in patients with androgen insensitivity syndrome (AIS). This work was designed to find out if peripheral aromatase activity could be related to a defect in androgen action in prepubertal children with male pseudohermaphroditism. Fibroblast estrogen production was assayed by a highly specific enzymatic determination. Foreskin fibroblast strains were raised from 17 children with partial androgen insensitivity (PAIS) as defined by dihydrotestosterone binding activity in cells. Results are expressed as pmol estrogens/mg proteins synthetized/day when cultured fibroblasts are incubated with D4-androstenedione. In normal prepubertal boys (n = 19), aromatase activity ranged between 5 and 10 pmol estrogens/mg proteins/day, while in postpubertal boys it varied between 15 and 34 pmol estrogens/mg proteins/day. In prepubertal boys with PAIS (n = 17) aromatase activity is highly elevated: 19.4 +/- 8.4 pmol/mg proteins/day. These results show that (a) peripheral aromatase activity is low before puberty and (b) fibroblast estrogen synthesis is significantly (p less than 0.001) increased in prepubertal children with PAIS. Our data suggest that low utilization of androgens by target cells stimulates the production of estrogen. Peripheral aromatase activity can thus be considered as a 'marker' of androgen insensitivity in prepubertal children with male pseudohermaphroditism.  相似文献   
4.
SM1 is a twelve-amino-acid peptide that binds tightly to the Anopheles salivary gland and inhibits its invasion by Plasmodium sporozoites. By use of UV-crosslinking experiments between the peptide and its salivary gland target protein, we have identified the Anopheles salivary protein, saglin, as the receptor for SM1. Furthermore, by use of an anti-SM1 antibody, we have determined that the peptide is a mimotope of the Plasmodium sporozoite Thrombospondin Related Anonymous Protein (TRAP). TRAP binds to saglin with high specificity. Point mutations in TRAP''s binding domain A abrogate binding, and binding is competed for by the SM1 peptide. Importantly, in vivo down-regulation of saglin expression results in strong inhibition of salivary gland invasion. Together, the results suggest that saglin/TRAP interaction is crucial for salivary gland invasion by Plasmodium sporozoites.  相似文献   
5.
Human Vg9/Vδ2 T cells (γδ T cells) are immune surveillance cells both in innate and adaptive immunity and are a possible target for anticancer therapies, which can induce immune responses in a variety of cancers. Small non-peptide antigens such as zoledronate can do activation and expansion of T cells in vitro. It is evident that for adoptive cancer therapies, large numbers of functional cells are needed into cancer patients. Hence, optimization of methods needs to be carried out for the efficient expansion of these T cells. Standardization of peripheral blood mononuclear cells (PBMCs) isolation was devised. Cytokines (interleukin 2 (IL-2) and interleukin 15 (IL-15)) and zoledronate were also standardized for different concentrations. It was found that an increased number of PBMCs were recovered when washing was done at 1100 revolution per minute (rpm). Significantly high expansion fold was (2524 ± 787 expansion fold) achieved when stimulation of PBMCs was done with 1 µM of zoledronate and both cytokines IL-2 and IL-15 supported the expansion and survival of cells at the concentrations of 100 IU/ml and 10 ng/ml respectively. 14-day cultures showed highly pure (91.6 ± 5.1%) and live (96.5 ± 2.5%) expanded γδ T cells. This study aimed to standardize an easy to manipulate technique for the expansion of γδ T cells, giving a higher yield.  相似文献   
6.
Chronic health effects are increasing in the world such as cancers, hormonal, reproductive, nervous, or immune diseases, even in young people. During regulatory toxicological subchronic tests to prevent these on mammalian health, prior commercialization of chemicals, including pesticides and drugs, or GMOs, some statistically significant findings may be revealed. This discussion is about the need to investigate the relevant criteria to consider those as biologically significant. The sex differences and the non linear dose or time related effects should be considered in contrast to the claims of a Monsanto-supported expert panel about a GMO, the MON 863 Bt maize, but also for pesticides or drugs, in particular to reveal hormone-dependent diseases and first signs of toxicities.  相似文献   
7.
Plantago is the most important genus of Plantaginaceae family and is used in traditional medicine around the world for different purposes. Plantago coronopus L., Plantago major L., Plantago media L. and Plantago lanceolata L. are most commonly used species of Plantago in traditional medicine in Turkey. The main goal of this study was to investigate the eventual anti-mitotic and anti-genotoxic effects of P. lanceolata L. leaf aqueous extracts (15 g/L and 30 g/L) on Allium cepa L. root tip meristem cells which were treated with 0.7% hydrogen peroxide. For this purpose, two different experiments were performed under the same conditions. In the first experiment, Allium cepa onion bulbs were treated with 0.7% H2O2 for 1 h. After the H2O2 treatment, the onion bulbs were treated with two different concentrations (15 g/L and 30 g/L) of P. lanceolata extracts for 24 h. In the second experiment, A. cepa onion bulbs were treated with two different extract concentrations (15 g/L and 30 g/L) for 24 h and then with 0.7% H2O2 for 1 h. The test concentrations were determined according to doses which are recommended in alternative medicinal usage by people. As positive and negative control 0.7% H2O2 and tap water was used, respectively. As a result, it was determined that aqueous extracts reduced mitotic index and chromosome aberrations in treatment groups in comparison with controls. These results showed that P. lanceolata aqueous extracts have anti-mitotic and anti-genotoxic effects.  相似文献   
8.
目的:为了研究日本人群β-链基因AvaⅡ酶切位点的遗传多态性以及该位点等位基因频率的分布。方法:采用PCR- RFLP技术,对35例无血缘关系的健康日本大学生的70条染色体进行检测,然后用X~2检验进行统计学处理。结果:等位基因B_1频率为0.4715,等位基因B_2频率为0.5287,杂合度H=0.5429,期望杂合度h=0.4986,多态信息量PIC=0.7635;B_1、B_2的传递规律和理论上预计的完全符合,认为日本人群β-链基因AvaⅡ酶切位点也具有遗传多态性,表明β-链基因AvaⅡ酶切位点具有适合信息,并且与国外报道的无显著性差异。结论:这对遗传制图、基因分离、疾病的关联研究,法医学个体识别和双生子的卵性鉴定有一定的价值。  相似文献   
9.
简明综述了黄酮的结构及其分类、生理活性与人类健康的关系,以及蕨类植物黄酮的研究进展等等,为了进一步开发蕨类植物黄酮提供了理论依据。  相似文献   
10.
新疆褐家鼠种群生命表及其在干旱区的生存能力分析   总被引:1,自引:0,他引:1  
从2000年至今,曾于野外捕捉的褐家鼠3 837只,其中雌鼠2 685只,雄鼠1 152只,经鉴定划分为幼年组(Ⅰ)、亚成年组(Ⅱ)、成年Ⅰ组(Ⅲ)、成年Ⅱ组Ⅳ、老年组(Ⅴ)等5个年龄组,其年龄结构探讨种群数量动态,结果表明,种群中Ⅱ龄的平均生命期望值最高1.0357,其次为Ⅲ龄0.9488。该种群中1龄个体占优势地位,种群属于增长性种群,种群内禀增长率rm为0.2789/年,年周限增长率λ为1.3217,世代时间T为2.623年,种群经一世代的净增殖率R0为2.0782。  相似文献   
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