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1.
The majority of intracranial teratoma are localized in pineal and sellar regions. In cerebellum, the teratoma is quite rare, the association with medulloblastoma is exceptional and was differentiated from medullomyoblastoma. We report one case of 5 years old boy with intracranial hypertension for 3 months. The cerebral computed tomography showed a tumor in the fourth ventricle. The histologic study of surgical specimens found a proliferation of component of medulloblastoma adjacent to mature teratoma with smooth and striated muscles, chondroid component, adipose tissue and epithelial elements. Our objective is to discuss the diagnosis, the hitogenesis and the prognosis of this tumor.  相似文献   
2.
Cerebral hydatid cysts represent 2-3% of all intracranial masses in endemic countries. Its incidence in posterior fossa is very rare. We report two cases of brainstem location. Clinically, the lesion exhibited signs of brainstem tumor. In two patients, CT scan showed a hypodense lesion. There was no enhancement after contrast administration. One patient was explored by MRI; on precontrast images, the lesion appeared homogeneous with hyposignal intensity and smooth limits. T2 weighted MRI and post contrast examination confirmed the cyst nature of the lesion. Surgery was performed in the two patients. The cyst was first aspirated and its membrane was then removed. Post operatively, one patient died, the other one is still alive but severely affected two years later. CT scan showed total disappearance of the cyst. The clinical presentation, radiological findings and surgical procedures are discussed.  相似文献   
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INTRODUCTION: Complete androgen insensitivity syndrome or testicular feminization syndrome (TF) is the most common form of male pseudohermaphrodism, caused by a failure of androgen receptor binding. Patient with male genotype 46 XY, has a female morphotype with well developed external sexual organs. EXEGESIS: - We report the case of a 29 year-old girl with a TF syndrome discovered during the exploration of a primary amenorrhoea. Bilateral orchidectomy was performed. The testis were immature; they showed bilateral leiomyoma of the tunica albuginea and multiple hamartomas on the right side. CONCLUSION: Benign tumors are developped in 80% of cases of TF and they are generally hamartomatous nodules of testis. Association of paratesticular leiomyoma to synchronous hamartoma has never been described, its histogenesis is discussed.  相似文献   
5.
A gene, qid74, of mycoparasitic filamentous fungus Trichoderma harzianum and its allies encodes a cell wall protein that is induced by replacing glucose in the culture medium with chitin (simulated mycoparasitism conditions). Because no trace of this gene can be detected in related species such as Gibberella fujikuroi and Saccharomyces cerevisiae, the qid74 gene appears to have arisen de novo within the genus Trichoderma. Qid74 protein, 687 residues long, is now seen as highly conserved tandem repeats of the 59-residue-long unit. This unit itself, however, may have arisen as tandem repeats of the shorter 13-residue-long basic unit. Within the genus Trichoderma, the amino acid sequence of Qid74 proteins has been conserved in toto. The most striking is the fact that Qid74 shares 25.3% sequence identity with the carboxyl-terminal half of the 1,572-residue-long BR3 protein of the dipteran insect Chironomus tentans. BR3 protein is secreted by the salivary gland of each aquatic larva of Chironomus to form a tube to house itself. Furthermore, the consensus sequence derived from these 59-residue-long repeating units resembles those of epidermal growth factor-like domains found in divergent invertebrate and vertebrate proteins as to the positions of critical cysteine residues and homology of residues surrounding these cysteines.  相似文献   
6.
A 34-year-old woman was hospitalized for exploration of amenorrhea and galactorrhea. She had experienced primary sterility, diagnosed 11 years earlier. Endocrine tests demonstrated hyperprolactinemia (serum prolactin 594 ng/ml). Magnetic resonance imaging (MRI) showed a soft tissue mass located within the posterior part of the sphenoidal sinus. The pituitary gland appeared normal. Medical treatment with bromocriptine was unsuccessful. Transsphenoidal tumor resection was performed. Histology reported adenoma, which was consistent with prolactin-producing tumor demonstrated by immunohistochemical staining for prolactin. Because of the persistence of hyperprolactinemia related to an intra-sphenoidal tumor remnant, bromocriptine (15 mg/d) was initiated. Menses ensued and prolactin level declined (49 ng/ml). One year later, the tumor remnant had disappeared on the MRI and the patient became pregnant. Ectopic adenomas of the sphenoidal sinus are of particular interest due to the diagnostic difficulties encountered. Nevertheless, the nature of the lesion can be determined from the endocrine manifestations. Some of these tumors respond to medical treatment, similar to intra sellar tumors. Surgery remains however the only means of obtaining definitive diagnosis and cure.  相似文献   
7.

Purpose

Appendicitis is by far the commonest major emergency general surgical operation. Histopathological examination of the appendix is routinely performed.

Methods

This study is a retrospective analysis of 24,697 appendectomies performed from January 2003 to December 2011. Pathological reports were analyzed for the following parameters: age, gender, and pathological diagnosis.

Results

Appendectomy specimens represent 17 % of all pathological reports. Acute appendicitis was present in 19,637 (79.5 %) patients. The perforation rate was 6.3 % and was significantly higher in adult patients. The negative appendectomy rate was 15 % and was significantly higher in female and adult patients. The incidence of negative appendectomies had clearly decreased over the 9-year period distribution. Incidental unexpected pathological diagnoses were noted in 226 (0.9 %) appendectomy specimens. Neoplastic lesions were present in 171 cases (0.7 %); they include carcinoid, adenocarcinoma, and mucinous neoplasms.

Conclusions

Routine pathological examination of appendectomy specimens is expensive. With advances in technology and imaging modalities, the diagnosis of acute appendicitis has improved, with a subsequent significant reduction in negative appendectomy. There are still a number of unusual diagnoses found in appendicectomy specimens supporting the continued use of routine histology.  相似文献   
8.
Aneurysmal bone cyst (ABC) is a benign lesion that often starts off the metaphysis of long bones and which, as it grows, may blow out bone. Only 3%-6% of cases are located in the skull. Spontaneous recovery has been reported. These cases occur more often in adults and in pelvic locations. Spontaneous regression at the skull level remains a very rare entity and few cases were described in the literature. Here, the authors report another case of spontaneous rapid regression of ABC of the skull in a 7-year-old boy revealed by gradually increasing painless hard swelling in the right frontal bone region with rapid spontaneous regression within 15 days. The authors will also proceed with an overview concerning this rare entity.  相似文献   
9.
Acute exposure to pesticides can cause hepatotoxicity. Our study pertains to the potential ability of selenium and/or vitamin E, used as nutritional supplements, to alleviate oxidative stress induced by dimethoate. Female Wistar rats were randomly divided into seven groups of six each: group I served as controls; group II received in their drinking water dimethoate (2 g L−1); group III received both dimethoate and selenium (0.5 mg/kg of diet); group IV was treated with dimethoate and vitamin E (100 mg/kg of diet); group V received dimethoate+selenium+vitamin E and groups VI and VII received either selenium or vitamin E. The exposure of rats to dimethoate for 30 days promoted oxidative stress with an increase in malondialdehyde and a decrease in glutathione and non-protein thiol levels. A decrease in glutathione peroxidase, superoxide dismutase and catalase activities was also observed. While, plasma transaminases, lactate dehydrogenase activities and bilirubin levels increased. Co-administration of selenium and/or vitamin E through diet improved the biochemical parameters cited above. Liver histological studies confirmed biochemical parameters and the beneficial roles of selenium and vitamin E.  相似文献   
10.
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