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The study aims to discuss the effects of aging on the male reproductive system. A systematic review was performed using PubMed from 1980 to 2014. Aging is a natural process comprising of irreversible changes due to a myriad of endogenous and environmental factors at the level of all organs and systems. In modern life, as more couples choose to postpone having a child due to various socioeconomic reasons, research for understanding the effects of aging on the reproductive system has gained an increased importance. Paternal aging also causes genetic and epigenetic changes in spermatozoa, which impair male reproductive functions through their adverse effects on sperm quality and count as, well as, on sexual organs and the hypothalamic-pituitary-gonadal axis. Hormone production, spermatogenesis, and testes undergo changes as a man ages. These small changes lead to decrease in both the quality and quantity of spermatozoa. The offspring of older fathers show high prevalence of genetic abnormalities, childhood cancers, and several neuropsychiatric disorders. In addition, the latest advances in assisted reproductive techniques give older men a chance to have a child even with poor semen parameters. Further studies should investigate the onset of gonadal senesce and its effects on aging men.  相似文献   
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Vitamin D deficiency not only causes low bone mass but also may lead to neuropsychiatric disorders. In the present case, vitamin D supplementation reduced obsessive–compulsive disorder (OCD) symptoms associated with streptococcal infection in a 7‐year‐old boy. Sudden onset of symptoms, including excessive hand washing and fear of touching anything, had occurred 1 month before presentation. Although there are few studies on a possible causal relationship between vitamin D and neuropsychiatric disorders, the present report; together with previous data, suggest an etiological role of vitamin D‐related immune processes.  相似文献   
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OBJECTIVE: The objective of this study was to investigate the relationship between occupation and head and neck cancers. PATIENTS AND METHODS: In this case-control study, 206 Turkish patients with head and neck cancers comprised the case group. The control group consisted of 206 age- and sex-matched patients without malignant disease. All patients completed a questionnaire regarding occupation; tobacco and alcohol consumption; educational status; and history of any systemic disease, benign head and neck disease, and cancer among family members. High-risk jobs were considered those in the industries of construction, wood, mining, metal, chemistry and agriculture. RESULTS: Patients with head and neck cancers worked in high-risk occupations more frequently than did controls [odds ratio (OR): 3.42, p<0.05]. Cancer risk decreased with the increase in time interval between quitting the high-risk job and time of interview. Smokers were at higher risk than nonsmokers (OR: 3.33, p<0.05). The risk was also higher in patients who drank alcohol regularly (OR: 1.59, p<0.05). However, occupation was found to be an independent high-risk factor for head and neck cancers in regression analysis. Frequency of benign head and neck disease and family history of cancer were not significant risk factors (p>0.05). CONCLUSION: Our analysis showed that occupation and smoking were significant independent risk factors for the development of head and neck cancers among workers.  相似文献   
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Nonclassical target organs recently defined for vitamin D, a major regulator of calcium phosphorus homeostasis and bone health, include reproductive ones. This compilation study focuses on the potential effects of vitamin D on female reproductive functions. Vitamin D receptor enzymes that metabolize vitamin D are expressed in both central and peripheral reproductive organs. Most studies suggest that vitamin D may be directly or indirectly related to gonadal functions. Vitamin D's effects on reproductive functions may be indirectly related to diseases such as polycystic ovary syndrome (PCOS), uterine leiomyomas, and endometriosis. In case of vitamin D deficiency during infertility treatment, vitamin D supplementation can be recommended especially for women who have PCOS, insulin resistance, or low anti-Mullerian hormone levels. Supplementation, however, should take into account possible toxic effects of high-dose vitamin D. To be able to recommend measuring vitamin D as a routine screening test and to better understand the effects of vitamin D and its supplementation on female reproductive functions, larger randomized controlled prospective studies are needed.  相似文献   
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