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Geneticists have, for years, understood the nature of genome‐wide association studies using common genomic variants. Recently, however, focus has shifted to the analysis of rare variants. This presents potential problems for researchers, as rare variants do not always behave in the same way common variants do, sometimes rendering decades of solid intuition moot. In this paper, we present examples of the differences between common and rare variants. We show why one must be significantly more careful about the origin of rare variants, and how failing to do so can lead to highly inflated type I error. We then explain how to best avoid such concerns with careful understanding and study design. Additionally, we demonstrate that a seemingly low error rate in next‐generation sequencing can dramatically impact the false‐positive rate for rare variants. This is due to the fact that rare variants are, by definition, seen infrequently, making it hard to distinguish between errors and real variants. Compounding this problem is the fact that the proportion of errors is likely to get worse, not better, with increasing sample size. One cannot simply scale their way up in order to solve this problem. Understanding these potential pitfalls is a key step in successfully identifying true associations between rare variants and diseases.  相似文献   
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There is a large and growing population of long-term cancer survivors. Primary care physicians (PCPs) are playing an increasingly greater role in the care of these patients across the continuum of cancer survivorship. In this role, PCPs are faced with the responsibility of managing a range of medical and psychosocial late effects of cancer treatment. In particular, the sexual side effects of treatment which are common and have significant impact on quality of life for the cancer survivor, often go unaddressed. This is an area of clinical care and research that has received increasing attention, highlighted by the presentation of this special issue on Cancer and Sexual Health. The aims of this review are 3-fold. First, we seek to overview common presentations of sexual dysfunction related to major cancer diagnoses in order to give the PCP a sense of the medical issues that the survivor may present with. Barriers to communication about sexual health issues between patient/PCPs in order are also described in order to emphasize the importance of PCPs initiating this important conversation. Next, we provide strategies and resources to help guide the PCP in the management of sexual dysfunction in cancer survivors. Finally, we discuss case examples of survivorship sexual health issues and highlight the role that a PCP can play in each of these case examples.  相似文献   
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Context The root of Helicteres angustifolia L. (Sterculiaceae) has been used as folk herbal drug to treat cancer, bacterial infections, inflammatory, and flu in China. However, there is no report on its antidiabetic activity.

Objective This study evaluates the antidiabetic activity of ethanol extract from H. angustifolia root.

Materials and methods The promoting effect of H. angustifolia root ethanol extract (25, 50, and 100 μg/mL) on glucose uptake was evaluated using HepG2 cell, differentiated C2C12 myotubes, and differentiated 3T3-L1 adipocytes. The antidiabetic activity of the extract was assessed in vivo using STZ-induced diabetic rats by orally administration of the extract (200 and 400?mg/kg b.w.) once per day for 28 d. Blood glucose, TG, TC, TP, HDL-C, UA, BUN, AST, ALT, insulin, and HOMA-IR were analyzed.

Results The results showed that the extract increased glucose uptake in C2C12 myotubes and 3T3-L1 adipocytes with an IC50 value of 79.95 and 135.96 μg/mL, respectively. And about 12%, 19%, and 10% (p < 0.05) in HepG2 cells when compared with the control at the concentration of 25, 50, and 100 μg/mL, respectively. After 28 days’ treatment with the extract, significant reduction was observed in blood glucose, HOMA-IR, TC, TG, UA, BUN, AST, and ALT levels, while the levels of TP and HDL cholesterol increased.

Discussion and conclusion These results suggest that H. angustifolia root ethanol extract possess potent antidiabetic activity, which is the first report on antidiabetic activity of this plant.  相似文献   
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骨碎补是历代临床常用中药,具有疗伤止痛、补肾强骨、消风祛斑等功效。其主要含黄酮、苯丙素、三萜、酚酸及其苷等类化学成分,现代研究表明骨碎补具有抗骨质疏松、促进骨折愈合、促软骨再生、护牙健齿、保护肾功能、抗炎、防治中毒性耳聋、降血脂等多种生物活性,开发前景广阔。本文对近年来骨碎补的化学成分、药理作用及临床应用研究进行综述,以期为骨碎补的进一步深入系统的研究和开发利用提供依据。  相似文献   
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狼疮抗凝物是发生静脉血栓栓塞症的危险因素之一,在静脉血栓栓塞症患者中检测狼疮抗凝物,对治疗方案抉择和疗效预后判断等方面具有重要意义。目前尚无相关文献对狼疮抗凝物检测在静脉血栓栓塞症中的应用进展进行分析总结,为加深对此类患者的认识,更好地帮助临床医生对此类患者进行合理的诊治和管理,现就有关流行病学、检测注意事项及检测结果在静脉血栓栓塞症中的价值和相关治疗进行综述。  相似文献   
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