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991.
Leprosy is a chronic granulomatous disease of the skin and peripheral nerves caused by Mycobacterium leprae. Among mycobacterial infections, leprosy is rare in renal transplant recipients. Here, we report the manifestations of lepromatous leprosy in a 41-year-old renal transplant recipient. Before the renal transplant, the patient had recurrent bullous lesions on his extremities with no systemic complaints. He was on an immunosuppressive regimen that included prednisolone (1 mg/kg/d), cyclosporine (6 mg/kg), and mycophenolate mofetil (2000 mg/d), and had 2 serologically confirmed acute episodes of cytomegalovirus infection that responded favorably to intravenous ganciclovir. The density of his bullous skin lesions decreased after renal transplant. During his regular posttransplant visits, we noticed a decrease in his eyebrow hairs on their lateral margins bilaterally. Later, he developed generalized, symmetric, erythematous papules. With a positive acid-fast bacilli with Fite staining, the results of a skin biopsy showed diffuse foamy histiocyte infiltration in the dermis. These findings are compatible with lepromatous leprosy. After antileprosy therapy, no deterioration of renal allograft function or lepra reactions was noted in a 4-month follow-up. Clinicians should consider leprosy in the differential diagnosis of skin lesions in immunocompromised hosts, and in particular, solid organ transplant recipients in endemic areas.  相似文献   
992.
A sample size of 30 degrees of freedom (df) for bone mineral density (BMD) precision studies may be insufficient for reliably categorizing change. Monte Carlo simulation was used to evaluate the effect of precision study sample size on identifying change in clinical patients. Least significant change (LSC) from 198 spine and 193 total hip scan-pairs was used to categorize change for 1420 patients undergoing BMD monitoring. Relative to this reference change fraction (RCF), LSC limits were identified that gave specified deviations from the RCF (-25% to +25%). Confidence limits (95% and 80%) for these LSC values (5 to 500 df) were estimated using 'bootstrap' samplings. A sample size providing 140 df is needed to avoid overdetecting spine change by 5% and 150 df to avoid underdetecting spine change by 5% with 95% confidence limits. A sample size of 30 df resulted in up to a 12.5% overdetection and 10.0% underdetection of spine or hip change based upon 95% confidence limits. In conclusion, assessing the effect of precision study sample size on classifying change in monitored patients is an important element of the precision assessment that is neglected in current recommendations. Sample sizes larger than 30 df are required if low levels of categorization error are to be achieved.  相似文献   
993.
目的阿尔茨海默病(Alzheimer's disease, AD)是主要的神经退行性疾病之一,其特征主要表现为痴呆,包括学习与记忆的衰退。本研究旨在探索薰衣草(唇形科,薰衣草属)水提取物对AD大鼠空间学习和记忆的影响。方法 Wistar大鼠分为对照组和AD 组,通过给大鼠脑室注射10 ?g A?1-42 建立AD模型。20天后,两组大鼠进行为期5天的水迷宫空间记忆采集实验(每天4次),紧接着进行一次空间探索实验。实验结束后,分别给予AD组和对照组大鼠不同剂量的薰衣草水提取物(50、100、200 mg/kg) 或 0.4 mL/kg 蒸馏水,每天一次共20天。随后,重复上述水迷宫实验。结果在水迷宫实验的第一阶段,AD组大鼠找到平台的潜伏期显著高于对照组大鼠,而在第二阶段,接受蒸馏水注射的对照和AD大鼠找到平台的潜伏期没有差异,说明水迷宫运动本身能提高AD大鼠的空间学习能力。在第二阶段空间记忆采集实验中,与接受蒸馏水注射的同类大鼠相比,接受薰衣草水提取物注射的对照和AD大鼠找到平台的潜伏期显著降低。此外,200 mg/kg 薰衣草水提取物能显著提高对照和AD大鼠的空间探索能力。结论薰衣草水提取物能有效逆转AD ...  相似文献   
994.
Objective: This study sought to assess the clinical signs and subjective symptoms of TMD, including the occlusal condition.

Methods: Recruited individuals included 123 patients (58 men, 65 women) aged 15 to 65 years (mean 38.6 years) who had been referred to the TMD department. Helkimo dysfunction, occlusal, and anamnestic indices were used to assess signs of TMD, occlusal condition, and symptoms, respectively. Relationships of occlusal factors with signs and symptoms of TMD were evaluated by Spearman’s correlation test. Associations of TMD with sex and age distributions were assessed by Mann–Whitney and Spearman’s test, respectively.

Results: The prevalence of signs and symptoms was as high as 75%. Occlusal factors had significant associations with signs and symptoms of TMD.

Conclusion: Prevalence of TMD in the study population was high, without preference for age or sex. Occlusal factors may play a role in the etiology of TMD.  相似文献   
995.
The aim of this study was to evaluate the postoperative morbidity at the donor site and the long-term outcome after the harvest of bicortical iliac bone grafts, including the iliac crest and the anterior superior iliac spine (ASIS), by using a confirmed score. We retrospectively examined 54 consecutive patients who had had vascularised iliac bone grafts harvested to reconstruct different parts of the mandible. We used the Harris Hip Score to evaluate objectively the long-term postoperative morbidity at the donor site. Of 54 patients, 20 were female (37%) and 34 male (63%), with a mean age of 49 years (range 12–81). The causes of the bony defects were malignancy (n = 37, 69%), benign tumours (n = 7, 13%), osteomyelitis (n = 9, 17%), and atrophy of the alveolar ridge (n = 1, 2%). All transplants healed adequately. A total of 38/52 patients (73%) had a score of more than 80 points, which defines clinical success. Vascularised iliac bone grafts offer excellent bony dimensions with optimal shape to be used for reconstruction of different parts of the mandible. They can be harvested bicortically, including the iliac crest and the ASIS, with acceptable morbidity at the donor site. The Harris Hip Score is an appropriate tool for the evaluation of long-term impairment at the donor site after the harvest of vascularised iliac bone grafts, and it could be used to compare the results of different studies.  相似文献   
996.
997.
The role of massa intermedia (MI) is poorly understood in humans. Recent studies suggest its presence may play a role in normal human neurocognitive function while prior studies have shown the absence of MI correlated with psychiatric disorders. There is growing evidence that MI is likely a midline white matter conduit, responsible for interhemispheric connectivity, similar to other midline commissures. MI presence was identified in an unrelated sample using the Human Connectome Project database. MI structural connectivity maps were created and gray matter target regions were identified using probabilistic tractography of the whole brain. Probabilistic tractography revealed an extensive network of connections between MI and limbic, frontal and temporal lobes as well as insula and pericalcarine cortices. Women compared to men had stronger connectivity via their MI. The presented results support the role of MI as a midline commissure with strong connectivity to the amygdala, hippocampus, and entorhinal cortex.  相似文献   
998.
The frequency of sensitization to contact allergens varies in different countries because of both genetic and, more importantly, allergen exposure variations. The objective is to determine the frequency of sensitization to contact allergens in Iranian patients with dermatitis. 250 patients with a clinical diagnosis of contact dermatitis and/or atopic dermatitis were evaluated with a 28-allergen screening series recommended by the German Contact Dermatitis Research Group from September 2002 to April 2004 in Tehran, Iran. The patches were applied on the back of the patients, removed after 24 hr and the readings were taken on 24 hr, 48 hr and 72 hr after application. 126 patients (50.4%) showed at least 1 positive reaction, and 23 patients (9.2%) had more than 2 positive reactions. 189 (84.4%) of 224 positive reactions had past and/or present clinical relevance. The 5 most common allergens were nickel sulfate 70 (28.0%), cobalt chloride 32 (12.8%), para-tertiarybutyl phenol formaldehyde resin 20 (8.0%), potassium dichromate 13 (5.2%) and colophony 13 (5.2%). Contact allergy to nickel sulfate was significantly more common in female patients and in patients under 40 years of age (P < 0.05). Nickel sulfate is the most common contact allergen in Iran, mostly affecting women and younger patients probably because of more exposure.  相似文献   
999.

Background

There are contradictory reports on the relationship between acne vulgaris and cigarette smoking. The objective of this study was to examine the relation between acne and cigarette smoking in a case-control study.

Methods

A questionnaire on smoking habits was offered to 350 patients with acne vulgaris and 350 patients suffering from skin diseases other than acne, aged 15 – 40 years, attending in a skin clinic in Tehran, Iran. The patients completed the questionnaires anonymously in the waiting room.

Results

Two hundred and ninety-three patients with acne (response rate 83.7 %) and 301 patients with other skin diseases (response rate 86.0 %) completed the questionnaires. Twelve acne patients (4.1 %) and 27 control patients (9.0 %) were current smokers (odds ratio = 0.43, 95% confidence limits 0.22 – 0.87, p < 0.05). But after adjustment for sex, this difference was not significant (odds ratio: 0.61, 95% CI: 0.30–1.26, p > 0.05, Mantel-Haenszel test).

Conclusion

An association between acne and cigarette smoking was not found in this study.  相似文献   
1000.
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