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Background Malignant melanoma risk factors have been studied in different geographical area populations. However, no study has focused on risk factors which are more frequently associated to the over 60's age group. Methods A case‐control study was performed that included 160 patients age ≥ 60 years diagnosed of cutaneous melanoma and 318 controls matched for age and sex. Both groups were assessed, by personal interview and physical examination, for different phenotype characteristics (hair and eye color, phototype), the presence of other cutaneous lesions (solar lentigines, actinic keratoses and nevi), degree and type of solar exposure and personal and family past history of cutaneous or non‐cutaneous cancer. Differences were evaluated by contingency tables and univariate and multivariate logistic regression. Results Of 17 factors, those risk factors with a strong effect on the development of melanoma in the elderly were: fair eyes, severe sunburns, years of occupational sun exposure, smoking, > 50 melanocytic nevi and personal history of NMSC and other non‐cutaneous neoplasias. Conclusions Tobacco smoking is an independent risk factor for cutaneous melanoma in the elderly. Intense (both acute and chronic) sun exposure and constitutional features, such as tumor susceptibility (NMSC, non‐cutaneous neoplasias, and multiple nevi) are also associated with melanoma risk. All these factors should help to better design educational campaigns in older people.  相似文献   
995.
While access to and control over assets can minimize women’s HIV risk, little is known about the processes through which property rights violations increase the sexual transmission of HIV. The current study focused on two rural areas in Nyanza and Western Province, Kenya where HIV prevalence was high (23.8–33 %) and property rights violations were common. The current work drew on in-depth interview data collected from 50 individuals involved in the development and implementation of a community-led land and property rights program. The program was designed to respond to property rights violations, prevent disinheritance and asset stripping, and reduce HIV risk among women. In our findings, we detailed the social and economic mechanisms through which a loss of property rights was perceived to influence primary and secondary prevention of HIV. These included: loss of income, loss of livelihood and shelter, and migration to slums, markets, or beaches where the exchange of sex for food, money, shelter, clothing, or other goods was common. We also examined the perceived influence of cultural practices, such as wife inheritance, on HIV risk. In the conclusions, we made recommendations for future research in the science-base focused on the development of property ownership as a structural HIV prevention and treatment intervention.  相似文献   
996.
The scalp is a common site of involvement of psoriasis and, for many patients, is a challenging aspect of their disease. This can be attributed not only to the scaling, itching and cosmetic embarrassment that go with scalp psoriasis, but also to the fact that the scalp skin is relatively inaccessible, making topical therapies difficult to apply. The proximity of sensitive facial skin can also limit the use of potentially irritating topical treatments. Nevertheless, the specific challenges of scalp psoriasis are often neglected by treatment guidelines. This paper summarizes the discussions that took place at an international conference of experts convened in Geneva, Switzerland, in March 2008. The objective of the meeting was to review the available treatments for scalp psoriasis in terms of efficacy, safety, convenience, and the implications for patient compliance with treatment. In addition, definitions of mild, moderate and severe scalp psoriasis were agreed. This paper presents a treatment algorithm that includes recommendations for patients in all three categories. It considers the role of potent topical corticosteroids, vitamin D3 derivatives, salicylic acid preparations, and photo- and radiotherapy, as well as systemic therapies, including newer biological agents, for patients with widespread psoriasis with scalp involvement. Data from clinical trials indicate that a potent topical corticosteroid in a short-contact formulation is the most appropriate treatment for most patients with scalp psoriasis.  相似文献   
997.
1987年,当NMDP开始为患者选择匹配的志愿捐献者进行造血干细胞移植(hematopoietic cell transplant,HCT)时,干细胞来源只能通过NMDP提供BM.1997年情况发生了变化,NMDP批准使用动员剂采集外周血造血干细胞.最初该方案只用于之前捐献过BM的捐献者,1999年开始,可以用于首次捐献者,到2003年,PBSC捐献的数量超过了BM捐献数量,现在PBSC捐献占成年捐献者的70%以上.从捐献者的角度来看,这两种不同来源干细胞的捐献方式,在捐献后恢复和安全  相似文献   
998.
A disconnection procedure was used to test whether the hippocampus and anterior thalamic nuclei form functional components of the same spatial memory system. Unilateral excitotoxic lesions were placed in the anterior thalamic (AT) nuclei and hippocampus (HPC) in either the same (AT-HPC Ipsi group) or contralateral (AT-HPC Contra group) hemispheres of rats. The behavioral effects of these combined lesions were compared in several spatial memory tasks sensitive to bilateral hippocampal lesions. In all of the tasks tested, T-maze alternation, radial arm maze, and Morris water maze, those animals with lesions placed in the contralateral hemispheres were more impaired than those animals with lesions in the same hemisphere. These results provide direct support for the notion that the performance of tasks that require spatial memory rely on the operation of the anterior thalamus and hippocampus within an integrated neural network.  相似文献   
999.
目的立足于基因组水平考察日本血吸虫慢性感染小鼠CD_4~+ T应答中抑制性因素的参与及可能的调控作用。方法采用高密度寡核苷酸芯片(Affymetrix芯片)对日本血吸虫感染0、3、6、13周小鼠脾脏中的CD_4~+ T细胞进行全基因组分析,获得相关抑制性因子的基因表达谱。结果基因芯片结果显示日本血吸虫感染从急性期至慢性期过程中抑制性因子的表达基因表达逐步上调,呈现基本一致的变化,包括抑制性细胞因子、阻断抗体、细胞凋亡、负调控分子的高表达等。结论从胞内信号转导通路至细胞凋亡的整体水平,多层次因素参与了日本血吸虫感染宿主免疫应答的负调控机制。  相似文献   
1000.
To investigate gene loss in poxviruses belonging to the Chordopoxvirinae subfamily, we assessed the gene content of representative members of the subfamily, and determined whether individual genes present in each genome were intact, truncated, or fragmented. When nonintact genes were identified, the early stop mutations (ESMs) leading to gene truncation or fragmentation were analyzed. Of all the ESMs present in these poxvirus genomes, over 65% co-localized with microsatellites—simple sequence nucleotide repeats. On average, microsatellites comprise 24% of the nucleotide sequence of these poxvirus genomes. These simple repeats have been shown to exhibit high rates of variation, and represent a target for poxvirus protein variation, gene truncation, and reductive evolution.  相似文献   
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