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991.
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   
992.
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   
993.
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   
994.
Background: The diagnosis of an enterovirus infection may be achieved through direct virus detection from fecal or cerebrospinal fluid (CSF) samples by virus isolation or PCR. Serologically, a significant rise in antibody titer may be detected and different enteroviral types can be differentiated using the neutralization assay. Patients and Methods: We investigated the contribution of these different laboratory parameters to the diagnosis of enterovirus infections occurring in the Frankfurt am Main area during the years 1997 to 1999, including an echovirus 30 outbreak in a group of children with aseptic meningitis in 1997. Samples were referred from 1,013 patients; virus isolation was attempted from 579 CSF specimens and from 400 stool samples. 208 CSF samples were tested by PCR. Results: During the echorivus 30 outbreak we identified 22.3% of samples as positive, almost exclusively echovirus 30. In 1998 only 7.1% of samples were positive and a rather broad range of agents was isolated. In 1999 10.4% were positive, predominantly coxsackie B5 and echovirus 11. We could show that in acute enterovirus infections, virus detection by cell culture and PCR is superior to serological methods (neutralization assay and IgM assay). For virus isolation, there was a higher rate of positives from stool compared to CSF (1997: 27.8% versus 25%; 1998: 14.4% versus 3%; 1999: 17.9% versus 8.5%). When comparing PCR and virus isolation from the CSF, the former yielded a higher rate of positive results but was not clearly superior to virus isolation from CSF. Conclusion: The recommended method for the diagnosis of acute enterovirus infections is virus isolation from feces. In cases of suspected aseptic meningitis virus isolation and PCR are valuable for the direct detection of virus in CSF. Received: March 31, 2000 · Revision accepted: March 5, 2001  相似文献   
995.
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   
996.
PURPOSE: To analyse the auxological data of children with myelomeningocele (MMC) on growth hormone (GH) therapy whose growth data was documented within KIGS (Pfizer International Growth Database). Longitudinal growth data of a sub-group of pre-pubertal children were studied after a treatment period of 3 years. PATIENTS AND METHODS: Eighty patients (38 m, 42 f) with MMC with a median chronological age (CA) of 11.6 years (at latest visit) on GH were registered in the KIGS database. In 52 patients, GH deficiency was documented. GH therapy started with a median dose of 0.23 mg kg(-1) per week. The 3-year longitudinal growth was analysed in 21 patients (13 m, 8 f; median CA 9.2 years, latest visit), all of whom were pre-pubertal at start and during GH therapy. RESULTS: GH therapy started at 7.5 years with a dose of 0.23 mg kg(-1) per week. Birth length SDS (-0.51) and mid-parental height SDS (+0.07) were in the normal range. BMI SDS at start was +0.24, at latest visit -0.03. After a median treatment duration of 3.0 years (latest visit), height SDS improved from -2.97 (start of GH) to -2.01. The sub-group of pre-pubertal MMC patients started GH therapy (dose 0.22 mg kg(-1) per week) at 6.2 years. Growth velocity (GV) SDS increased significantly (at start: -1.77; 1 year: +2.60, 2 years: +2.25, 3 years: +1.24), thus height SDS improved from -3.25 at start to -1.87 at 36 months. BMI SDS was in the normal range and remained unchanged during GH therapy. No major side effects of GH were recorded. CONCLUSION: GH had positive effects on height SDS in MMC patients. The analysis of the longitudinal growth data of pre-pubertal MMC patients showed a significant increase in GV SDS and improvement of height SDS.  相似文献   
997.
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   
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