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21.
Cicatricial conjunctivitis may be a sequel to systemic disorders (eg, Stevens-Johnson syndrome, cicatricial pemphigoid) or local disorders such as chemical burns. The cicatrisation is often associated with corneal epithelial changes that cause visual loss. These have been attributed to encroachment of the conjunctival epithelium over the cornea. However, the epithelial anomalies are poorly understood. We investigated the corneal epithelial changes in cicatricial conjunctivitis with an immunohistochemical study of intermediate filaments in normal and pathological specimens. Our results show that the normal corneal epithelium is immunoreactive for cytokeratin 3 (CK 3) but not cytokeratin 19 (CK 19), whereas normal conjunctival epithelium is CK 3 negative and CK 19 positive. Conjunctiva artificially transposed over the cornea (after therapeutic conjunctival flap reconstruction) retained the normal pattern of conjunctival cytokeratin expression (CK 3 negative, CK 19 positive). Conversely, the entire corneal epithelium exhibited the normal cytokeratin pattern (CK 3 positive, CK 19 negative) in 82% of Stevens-Johnson, 80% of cicatricial pemphigoid, and 69% of chemical burns specimens. The findings suggest that conjunctival encroachment is not responsible for the changes at the corneal surface in cicatricial conjunctivitis and that the abnormal corneal epithelium is derived from native corneal cells in these diseases.  相似文献   
22.
International Urology and Nephrology - To evaluate outcomes of laparoscopic pyeloplasty (LP) in adults with poorly functioning kidney due to ureteropelvic junction obstruction (UPJO). A...  相似文献   
23.
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
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Pseudoangiosarcomatous squamous cell carcinoma, also called pseudovascular, pseudoangiomatoid or adenoid pseudovascular carcinoma, is an uncommon and highly aggressive variant of squamous cell carcinoma. Histologically, it is characterized by proliferation of atypical keratinocytes with acantholysis and formation of pseudovascular spaces, forming anastomosed channels lined with neoplastic cells that invade the dermis. These cells are positive for cytokeratin and negative for vascular markers such as CD31 and CD34. There are few reports of this variant in the literature. Skin, breast, lung and vulva involvement have been described, but to the best of our knowledge, no cases involving the penis has been described. This study aims to describe the first case of angiosarcomatous squamous cell carcinoma of the penis. The patient presented with a painful lesion in the penis associated with urinary retention. Macroscopic findings exhibited an ulcerative vegetating lesion that involving the entire glans and part of the penile body, as well as infiltration of penile structures and scrotal skin. Microscopy shows atypical proliferation of sarcomatous keratinocyte pattern mimicking vascular spaces. Human papilloma virus (HPV) biomarkers and polymerase chain reaction (PCR) were all negative. Advanced penile squamous cell carcinoma with aggressive lymph node metastasis. This report presents the first case of penile pseudoangiosarcomatous squamous cell carcinoma, as an important differential diagnosis.  相似文献   
26.
A new technique to correct persistent left superior vena cava (LSVC) drainage into the left atrium is described in a 14-year-old patient with situs inversus, left atrial isomerism common atrium, and mitral valve regurgitation. During surgery, occlusion of the LSVC markedly increased the venous pressure, precluding its ligation. Because of the malposition of the heart and the unusual atrial anatomy, correction with an intra-atrial baffle was not attempted. After correcting the intra-cardiac anomaly, the LSVC was divided and anastomosed to the "right" atrial appendage using a segment of PTFE graft. The postoperative course was uneventful and an angiogram demonstrated excellent performance of the graft.  相似文献   
27.
A long-term controlled field experiment on the interactions of the populations of Biomphalaria glabrata (target population) and B. straminea (competitor) was carried out in the county of Alhandra, state of Paraíba, Brazil, during the period 1980 through 1989. Results obtained in the current paper show that the snail B. straminea has strong competitive advantages over B. glabrata. In six out of nine streams the native population of B. glabrata were totally excluded and replaced by B. straminea. There is evidence showing that seasonal dryness has marked influence on the phenomenon studied in this paper. In all the streams were B. straminea already predominated, return of B. glabrata was never observed.  相似文献   
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Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented.  相似文献   
30.
The effects of a gestational exposure of 80 rats Wistar EPM-1 to nicotine and undernutrition was examined. The weight and histological alterations on the liver and lungs was evaluated on the rats and their offspring. A significantly lower weight gain, including liver and lung weight, was observed in nicotine exposed groups. There was no alteration of the placental weight. Decidual necrosis and hepatic congestion was frequent in the rats. Lung emphysema was found in the neonates.  相似文献   
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