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11.
目的:评价利用活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失的临床效果。方法:从2005-07/2007-12,本研究包括了9名男性化学性眼外伤患者(10眼)。所有患者接受了亲属活体异体结膜缘和羊膜移植,2例眼接受了睑缝术。用环孢菌素和泼尼松龙进行全身性免疫抑制。结果:在3例眼中观察到完全角膜上皮化(30%),其中1例在术后1.5mo出现免疫排斥,角膜溶解引起穿孔,加大全身性免疫抑制剂量来控制病情。3例眼中植片无法在角膜表面重新形成上皮,被定为原发性失败。其余4眼有部分上皮形成,但上皮细胞无法完全覆盖角膜表面。术前最佳矫正视力从手动到1m处数指,术后最佳矫正视力从光感到20/80。有5眼视力得到改进,不需其他治疗。手术失败的主要原因为干眼症和持续性炎症。结论:对于能控制泪量和眼部炎症的病例,亲属活体异体角膜缘和羊膜移植是治疗化学性眼外伤造成的角膜缘干细胞缺失最佳方法之一。  相似文献   
12.

Introduction

Oral peripheral and central giant cell granulomas are lesions with little-known etiology and pathogenesis.

Objective

The aim of this study was to compare matrix metalloproteinases-2 and osteopontin protein expression in the multinucleated giant cells and mononuclear cells of the peripheral and central giant cell granuloma lesions.

Methods

In this retrospective study, the presence of matrix metalloproteinases-2 and osteopontin in 37 cases of central giant cell granuloma and 37 cases of peripheral giant cell granuloma paraffin blocks were assessed by streptavidin-biotin immunohistochemistry. Independent sample t-test, Chi-square, Mann–Whitney tests and Spearman's rank correlation coefficient were used.

Results

The osteopontin was expressed in both multinucleated giant cells and mononuclear cells in all cases of peripheral and central giant cells granulomas. However, the matrix metalloproteinases-2 expression was positive in 86.5% of giant cells and it was positive in all of mononuclear cells in peripheral giant cells granuloma. In central giant cells granulomas, 91.8% of giant cells and all mononuclear cells were positive for matrix metalloproteinases-2 marker. Percentage and Intensity of staining were significantly higher in central than peripheral giant cells lesions, for both markers (p ? 0.05).

Conclusion

This study showed that the expression of osteopontin in giant cells supports the theory of osteolcastic nature of these cells. Also, the presence of osteopontin and matrix metalloproteinases-2 in mononuclear cells may indicate the monocyte-macrophage origin of these cells, as the differentiation of the precursors of the mononuclear stromal monocyte/macrophage to osteoclasts is possibly affected by the expression of osteolytic factors. Also, may be differences in biological behaviors of these lesions are associated with the level of osteopontin and matrix metalloproteinases-2 expression.  相似文献   
13.
Background: Aniridia is a rare developmental eye disorder characterized by complete or partial iris hypoplasia often accompanied with other ocular changes that affect the cornea, anterior chamber, lens, retina, and optic nerve. Most cases of aniridia are inherited with an autosomal dominant mode of inheritance caused by PAX6 mutations or deletions. To reveal the underlying genetic defect in a four-generation Iranian family with aniridia, we carried out a genetic screening of PAX6.

Methods: Complete ophthalmic examinations were performed for available affected family members. All PAX6 exons and their flanking regions were sequenced for affected individuals. Candidate variation was screened for segregation in the pedigree by Sanger sequencing. Bioinformatics prediction was done to evaluate the deleterious effects of the mutation on protein product. Real-time PCR was used to investigate the impact of the variant on PAX6 mRNA expression.

Results: All patients were diagnosed with isolated aniridia associated with variable phenotypic features including retinal detachment. A novel heterozygous deletion c.320_348delTGTCCGAGGGGGTCTGTACCAACGATAAC (p.Leu107HisfsX16) on PAX6 gene was detected. Decreased mRNA level of PAX6 in the affected individuals indicated that the mutation caused nonsense-mediated mRNA decay (NMD).

Conclusions: To the best of our knowledge, it is the first report on the genetics of aniridia in Iran. Segregation analysis, bioinformatics prediction and confirmation of NMD, all support the proposition that the novel observed PAX6 mutation is the cause of aniridia in the pedigree. Retinal detachment in some of the affected members, which is a rare reported phenotypic feature of aniridia patients, may be associated with this mutation.  相似文献   

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16.
Human papillomaviruses (HPVs) consist of more than 100 types and are known to be associated with numerous malignant tumors, including carcinomas of the mucosal and cutaneous epithelium. Non-melanoma skin cancer (NMSC) is the most frequently occurring malignancy worldwide in the Caucasian population. Some studies have shown that NMSC biopsy specimens harbor cutaneous as well as mucosal human papillomavirus, suggesting that mucosal types may play a role in development and progression of the tumor in skin. To investigate the presence of mucosal HPV types in skin lesions, we performed a retrospective study in which 288 paraffin embedded biopsies from benign and malignant skin lesions (NMSC) were collected. Using nested PCR with MY09/11 and GP5+/6+ primers mucosal HPVs were detected in 25.7% of malignant specimens, but just in 0.7% of benign lesions. Direct sequencing revealed HPV18 as the most frequent type, which was found in 75% of HPV-positive specimens. HPV16 and HPV56 were also detected, 22.3 and 2.7%, respectively. These findings suggest that, high-risk mucosal HPV types recently identified as significant risk factors for cervical cancer, may also represent a risk factor for non-melanoma skin cancer.  相似文献   
17.
Pediatrics metabolic syndrome (MetS) may be associated with the risk of development of chronic diseases in adulthood; however, the definition of pediatric MetS is unclear, and may vary with ethnicity. The primary goal of this study was to determine the best anthropometric predictors for pediatric MetS. For this purpose, 988 high school girls were recruited. Anthropometric indices and biochemical parameters were measured using standard procedures. The adapted MetS for pediatrics, including the IDF, NCEP, and two modified-NCEPs (Cook's and DeFerranti's) were used to establish a diagnosis of MetS. Statistical analysis was performed using SPSS and MedCalc softwares. Except for body frame size (r), the values for anthropometric indices were significantly lower in an individual without MetS. Waist to height (WHtR), BMI and hip circumference (HiC) showed the strongest association with the different MetS definitions. For the IDF definition, the highest sensitivity and specificity were observed for HiC (100.0, 85.2) and WHtR (100.0, 84.7); while for the NCEP definition, the r index showed the highest sensitivity (85.0); but low specificity made it inapplicable. For the Cook's definition of MetS, wrist circumference (WrC), HiC, WHtR, BMI and SR had similar sensitivity values with WC (92.9%), and HiC (85.3%) have the highest specificity. WHtR (86.05, 80.5), SR (86.05, 82.7) and HiC (76.7, 87.0) sensitivity and specificity were the best indexes for DeFerranti's criteria. Based on this date, we concluded that HiC and WHtR might be helpful as auxiliary indexes for pediatric MetS definition; however, further studies are required in both genders.  相似文献   
18.
Aim of the workTo assess the outcome of planned pregnancies in patients with systemic lupus erythematosus (SLE). Patients and methods: The study was conducted on 32 patients. The medical management included pre-pregnancy planning at the quiescent phase of the disease and after at least six months of clinical remission. The patients had a monthly visit during pregnancy and three months post-delivery. Disease flare was characterized by the recurrence of symptoms and signs in different organs, as well as the need for an increase in medication dose. Results: There were 36 planned pregnancies in 32 patients, of which 15 and 17 cases were primiparous and multiparous, respectively. The SLE flares were observed in 36.1% of the cases, 8.3% of which developed postpartum; moreover, they were moderate in severity and mostly involved the kidneys and joints. Pregnancy outcomes included18 (50%) cases ended in term labor; 13 (36.1%) pregnancies had preterm labor, and 5 (13.8%) pregnancies terminated with abortions. Furthermore, obstetric complications included 2(6.5%) patients with premature rupture of membranes, 5(15.6%) fetuses with intrauterine growth retardation, and 2(6.4%) mothers with preeclampsia. 10(27.7%) pregnancies occurred in patients with lupus nephritis. Cesarean section was performed on 24(77.4%) patients, and low birth weight was observed in 7(21.8%) infants. None of the infants had neonatal lupus, congenital deformities or infection. Conclusion: Pre-pregnancy planning in patients with SLE can considerably improve pregnancy outcomes. Neonatal lupus, congenital anomalies or infection were not present. SLE patients intending to become pregnant should be provided with close medical supervision for a safe maternal and fetal outcome.  相似文献   
19.

Objective

This study examined the prevalence of smoking, the rates of transitions, and predictors of transition through the three stages of smoking.

Methods

A total of 1785 high school students in Tabriz (northwest of Iran) were assessed at 2 time points with a 12-month interval in 2005 and 2006, regarding changes in smoking stages. The predictor variables were measured when the students were in the 10th grade. Logistic regression was employed to predict the different smoking stages at grade 11.

Results

The results showed that 14.3% (95% confidence interval, 12.3%-16.4%) and 2.8% (2.0%-4.0%) of the never smokers became experimenters and regular smokers, respectively, whereas 16.5% (12.4%-21.7%) of the experimenters became regular smokers. Among never smokers, participation in groups with at least one smoker (odds ratio, 1.24 (95% confidence interval, 1.05-1.47)), having smoker friends (1.85 (1.21-2.83)), and a positive attitude toward smoking (1.22 (1.02-1.46)) predicted smoking experience. Among the experimenters, those who had general risk behaviors (2.56 (1.12-5.87)) and participated in groups with at least one smoker (2.58 (1.26-5.31)) significantly progressed to becoming a regular smoker at the follow-up.

Conclusion

Prevention of smoking in adolescence should begin by focusing on the predictors of transition through smoking stages, especially participating in smoker groups.  相似文献   
20.
Journal of Thrombosis and Thrombolysis - Coagulation factor XIII (FXIII) covalently crosslinks pre-formed fibrin clots preventing their premature fibrinolysis. In plasma, FXIII circulates as a...  相似文献   
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