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101.

Background  

Liver injury due to dengue viral infection is not uncommon. Acute liver injury is a severe complicating factor in dengue, predisposing to life-threatening hemorrhage, Disseminated Intravascular Coagulation (DIC) and encephalopathy. Therefore we sought to determine the frequency of hepatitis in dengue infection and to compare the outcome (length of stay, in hospital mortality, complications) between patients of Dengue who have mild/moderate (ALT 23-300 IU/L) v/s severe acute hepatitis (ALT > 300 IU/L).  相似文献   
102.
Currently, the only reliable indicator of malignancy in pheochromocytoma is the presence of distant metastasis or extensive local invasion; predicting behavior of pheochromocytoma remains challenging. We aimed to correlate the behavior of pheochromocytoma with its expression of nm-23, cyclooxygenase (COX)-2, and galectin-3 (genes used to predict the course of some neoplastic diseases), evaluated immunohistochemically in 55 paraffin blocks of formalin-fixed pheochromocytoma specimens with confirmed behavior. In 3 (7%) of 44 benign and 7 (64%) of 11 malignant pheochromocytomas, there was negative nm-23 expression (P = .000). COX-2 immunoreactivity was positive in 10 (23%) of benign and 9 (82%) of malignant tumors (P = .000). Galectin-3 was expressed in 5 (11%) of benign and 9 (82%) of malignant pheochromocytomas (P = .000). Negative nm-23, along with positive COX-2 or galectin-3, predicted malignancy with 100% specificity. Dual negativity for galectin-3 and COX-2, along with nm-23 positivity, indicated benign behavior with 100% sensitivity. In early pheochromocytoma, evaluation of nm-23, galectin-3, and COX-2 expression could predict the outcome. Larger studies seem necessary to confirm the potential practical value of our findings.  相似文献   
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Pituitary adenomas without clinically active hypersecretion are summarized under the term non-functioning pituitary adenoma (NFPA). Since there are no specific serum markers, the differential diagnosis and treatment imply special difficulties. By using immunohistochemical methods we will have new insight into the nature and pathogenesis of these tumours. Ki-67 is a nuclear antigen detected by the monoclonal antibody MIB-1 and its labelling index (LI) is considered a marker of normal and abnormal cell proliferation. The aim of this study was to investigate the possible role of immunohistochemistry and MIB1-LI determination in NFPAs to predict tumoural behaviour and better management. In this clinicopathological study, 85 cases of NFPAs were analysed immunohistochemically. MIB1-LI was also determined in studied cases. Clinical presentation, treatment and follow-up data were also reviewed and the correlation between clinical and pathologic findings was established. Eighteen adenomas (21.2%) were immunoreactive to one or two adenohypophysial hormones of which 4 GH positive adenomas had aggressive behaviour (2 significant juxtasellar extensions and 2 recurrences). MIB-1 LI was more than 5% in only 5 cases including 2 invasive adenomas but with no evidence of recurrence. No significant statistical difference between clinical presentations in immunoreactive and non-immunoreactive NFPAs was observed except for unilateral temporal hemianopia which was more common in immunoreactive adenomas (P=0.022). NFPAs comprise several pathologically different types of tumours, some of which are potentially hormone producing, but some defects in hormone secretion or production of biologically inactive or insufficient amount of hormone may be the culprit in the lack of evidence of rising serum hormone levels. MIB-1 LI may be indicative of invasiveness but not a predictor of recurrence. Silent somatotropinomas may have more aggressive behaviour in comparison with other NFPAs.  相似文献   
105.
Oral Diseases (2010) 16 , 160–166 Objective: The aim of this comparative study was to analyze cytopathologically and chemico‐physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. Materials and methods: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back‐scattered) scanning electron microscope (SEM) and X‐ray microanalysis to study piercing fragments. Results: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X‐ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. Conclusions: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.  相似文献   
106.
SM Bromley  RL Doty 《Oral diseases》2010,16(3):221-232
Oral Diseases (2010) 16 , 221–232 Practitioners of oral medicine frequently encounter patients with complaints of taste disturbance. While some such complaints represent pathological processes specific to the gustatory system, per se, this is rarely the case. Unless taste‐bud mediated qualities such as sweet, sour, bitter, salty, umami, chalky, or metallic are involved, ‘taste’ dysfunction inevitably reflects damage to the sense of smell. Such ‘taste’ sensations as chicken, chocolate, coffee, raspberry, steak sauce, pizza, and hamburger are dependent upon stimulation of the olfactory receptors via the nasopharynx during deglutition. In this paper, we briefly review the anatomy, physiology, and pathophysiology of the olfactory system, along with means for clinically assessing its function. The prevalence, etiology, and nature of olfactory disorders commonly encountered in the dental clinic are addressed, along with approaches to therapy and patient management.  相似文献   
107.

Background

β-Amyloid precursor protein (APP) has been reported to play a role in the outgrowth of neurites from cultured neurons. Both cell-surface APP and its soluble, ectodomain cleavage product (APPs-α) have been implicated in regulating the length and branching of neurites in a variety of assays, but the mechanism by which APP performs this function is not understood.

Results

Here, we report that APP is required for proper neurite outgrowth in a cell autonomous manner, both in vitro and in vivo. Neurons that lack APP undergo elongation of their longest neurite. Deletion of APLP1 or APLP2, homologues of APP, likewise stimulates neurite lengthening. Intriguingly, wild-type neurons exposed to APPs-α, the principal cleavage product of APP, also undergo neurite elongation. However, APPs-α is unable to stimulate neurite elongation in the absence of cellular APP expression. The outgrowth-enhancing effects of both APPs-α and the deletion of APP are inhibited by blocking antibodies to Integrin β1 (Itgβ1). Moreover, full length APP interacts biochemically with Itgβ1, and APPs-α can interfere with this binding.

Conclusion

Our findings indicate that APPs-α regulates the function of APP in neurite outgrowth via the novel mechanism of competing with the binding of APP to Itgβ1.  相似文献   
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