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This prospective study aimed to compare the value of fine needle aspiration (FNA) cytology (FNAC) and flow cytometric immunophenotyping (FCI) with histopatopathology (HP) in the diagnosis and classification of non-Hodgkin lymphoma (NHL). Twenty-nine excised lymph nodes suspected of NHL were evaluated using FNAC, FCI, and HP. Specimens were divided into two equal parts; one for HP and the other for FNAC and FCI. Results were compared in terms of diagnosis (malignant, benign or reactive, and metastatic) and NHL class. With combined FNAC/FCI, 11 (37.9%) cases were diagnosed as NHL, 11 cases (37.9%) as reactive lymph node, six cases (20.6%) as Hodgkin's lymphoma, and one case (3.4%) as metastasis. HP revealed nine cases (31%) of NHL, five cases (17.2%) of reactive lymph nodes and all the diagnosed metastatic and Hodgkin's lymphoma. Considering histology as a gold standard method in diagnosis, the sensitivity, specificity, PPV and NPV of FNAC/FCI in differentiate malignant and benign lesion were 73.9%, 83.3%, 94.4%, and 45.5%, respectively and in differentiate NHL from others were 75%, 93.8%, 90%, and 83.3%, respectively. Cytology and HP in addition to FCI and HP are significantly different from determination of NHL lesions point of view (P = 0.001 and P < 0.0001, respectively). However, FCI can be considered as an adjunctive method for Cytology especially because Cytology is not competent enough to differentiate between benign lesions and Lymphoma. Additionally, FCI is shown to be an accurate method in classifying NHL.  相似文献   
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Purpose: Plasmid-encoded CTX-M-group of extended-spectrum β-lactamases (ESBLs) represent a significant and rapidly emerging problem in most part of the world. The aim of the present study was to describe the prevalence of CTX-M producing Klebsiella pneumoniae at Tehran hospitals. Materials and Methods: Clinical isolates of K. pneumoniae (n=250) were collected from 10 hospitals of Tehran. Susceptibility to antimicrobial agents, MIC of cefotaxime and ESBLs production of collected isolates were detected. All ESBL-producing isolates were screened for blaCTX-M genes using PCR and DNA sequencing. Molecular typing of blaCTX-M harboring isolates was performed by Pulsed–field gel electrophoresis assay. Results: Of 250 K. pneumoniae clinical isolates, 102 isolates revealed ESBLs – phenotype. PCR assay and sequencing detected blaCTX-M genes in 71.5% (n= 73) of ESBL-producing isolates. The prevalence of CTX-M -I and CTX-M-III clusters among these isolates was 35.61% (n=26) and 21.9 % (n=16) respectively. Coexistence of CTX-M -I and CTX-M-III clusters was found among 42.5% (n= 31) of isolates. Of 102 isolates that were positive in the phenotypic confirmatory test (PCT), 29 isolates (28.4%) did not produce any amplicons in PCR for blaCTX-M gene. The results of PCR for CTX-M -II and CTX-M-IV clusters were also negative. Analysis of the 31 CTX-M producing K. pneumoniae isolates by PFGE typing showed 26 distinct patterns. Conclusions: The blaCTX-M genes are widespread among Iranian isolates of K. pneumoniae. PFGE demonstrated the high diversity of K. pneumoniae harboring blaCTX-M in our study.  相似文献   
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Polycaprolactone (PCL) is used as a material of choice for surgical sutures, wound dressings, contraceptives, fixation devices and dentistry in paramedical sciences. In addition, adipose-derived stem cells (ASCs) have been shown to be effective in the treatment of acute and chronic wounds. This study aimed to evaluate the effect of electrospun PCL fibers on keratinocyte differentiation of ASCs and wound healing. PCL solution was electrospun and characterized. Isolated and characterized ASCs were differentiated into keratinocyte-like cells on a tissue culture plate (TCP) and PCL matrices and compared. PCL nano-/microfibers cultured with ASCs (test group) or alone (control) were implanted as a dermal substitute for wound healing. There were significant increases in the proliferation rate and expression level of cytokeratin 14, filaggrin and involucrin in cells cultured on PCL matrices compared to TCP (p < 0.05). After histological and immunological evaluation of the reconstituted skin, a thick epidermal layer with several skin appendages was evidently observed in the ASC/PCL group, whereas no real and mature epidermis was formed, especially in the central area of the healing wound in the pure PCL group on day 14. Pure PCL, if possessing suitable properties including good adhesiveness, high proliferative capability, inductive elasticity and stiffness for migration and differentiation, could drive the keratinocyte differentiation of ASCs and act as an efficient dermal equivalent to promote wound healing.  相似文献   
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Purpose: This study evaluated the effect of resin coating and chlorhexidine (CH) on microleakage of two resin cements (Panavia F2.0, Nexus 2) after water storage. Materials and Methods: Class V cavities were prepared on the facial and lingual surfaces of 120 intact human molars with gingival margins placed 1 mm below the cementoenamel junction. Indirect composite inlays were fabricated. The specimens were randomly assigned into six groups (n = 40). Indirect composite inlays (Gradia) were cemented as follows: Group 1 (control): inlays were cemented with Panavia F2.0 according to the manufacturer's instructions. Group 2: the ED‐primed (ED Primer, Kuraray Dental, Tokyo, Japan) dentin was coated with a resin layer before cementation of the inlays with Panavia F2.0. Group 3: a 2% CH solution was applied before bonding with Panavia F2.0. Group 4: after CH application, the primed dentin was coated with a resin layer before cementation with Panavia F2.0. Group 5: (control) after applying Optibond Solo Plus, the inlays were cemented with Nexus 2. Group 6: after etching, CH was applied, and cementation was performed similarly to group 5. Half the specimens in each group were stored in distilled water for 24 hours, while the other half were stored in distilled water for 6 months. After storage, the teeth were placed in 1% methylene blue dye for 24 hours, sectioned, and evaluated under a 20× stereomicroscope. Dye penetration was scored using 0 to 3 criteria. Data were analyzed using nonparametric tests. Results : Resin coating of ED primer for Panavia F2.0 significantly reduced microleakage at the gingival margins after 6 months (p < 0.05). CH application in Panavia F2.0 did not lead to a significant difference in the microleakage at both margins, after 24 hours and 6 months (p > 0.05). The application of CH showed significantly less microleakage than that of the control group at the gingival margins of Nexus 2 after 6 months. In general, gingival margins showed more microleakage than occlusal margins. Conclusion: An additional resin layer applied to a self‐etch cement can improve long‐term dentinal sealing for indirect restorations, while CH cannot; however, CH reduces gingival microleakage in an etch‐and‐rinse cement after aging.  相似文献   
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This study aimed to investigate the association between self-rated mental health (SRMH) and current health status of an Iranian population. A cross-sectional study was conducted on 3400 individuals selected through random sampling in Shiraz, Iran between January 2014 and March 2015. Data were gathered through face-to-face interviews. Statistical analyses were performed using the SPSS 19.0, and R.3.1.2 software was used for SCAD penalized logistic regression. The mean age of the participants was 38.5 (±?14.1 years). There were significant relationships between better SRMH and younger ages (p?<?0.001), and between better SRMH and better self-rated physical health (p?<?0.001). Individuals with poor SRMH were more likely to have signs and symptoms of medical diseases. SRMH, a component of self-rated health, was related to a variety of health problems in our study population. Therefore, paying attention to SRMH and mental well-being could be useful in making decision about implementation of preventive measures.  相似文献   
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Although it is well established that voluntary exercise can improve cognitive functions, the underlying mechanisms are largely unknown. Glucocorticoids play an important role in learning and memory functions. This study addressed whether the glucocorticoid system would play a role in the exercise-induced enhancement of learning and memory. Intact rats or those that were either adrenalectomized or daily given the corticosterone-synthesis inhibitor metyrapone were allowed to freely exercise in a running wheel for 10 days. Control animals were kept sedentary for this period. After this period, they were trained and tested on a water-maze spatial task using three-trial per day for 5 consecutive days, succeeded by a probe trial two days later. Exercise increased plasma corticosterone levels, as assessed after this 10-day period. Both adrenalectomy and metyrapone slightly reduced running-wheel activity. Adrenalectomy reduced the plasma corticosterone levels to almost zero whereas metyrapone selectively blocked the exercise-induced increase in corticosterone levels. Exercise significantly improved performance during both training and retention of the water-maze task whereas this effect was absent in both adrenalectomized and metyrapone-treated rats. These findings indicate that the glucocorticoid system play a crucial role in the beneficial effects of voluntary exercise on cognitive functions in rats.  相似文献   
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