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991.
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Diffuse cavernous hemangioma of the rectum is an unusual benign vascular lesion, marked by delayed diagnosis and often presenting recurrent rectal bleeding and anemia. Colorectal resection with coloanal anastomosis and construction of a colonic reservoir is the preferred surgical treatment. We report two cases of patients, a 23-year-old man and a 27-year-old woman, with cavernous hemangioma of the rectum, diagnosed by colonoscopy and confirmed by magnetic resonance imaging. Arteriography demonstrated vascular tumors in the rectal wall. Use of the embolization technique was not successful, since no large caliber vessel was available for this procedure. The patients underwent anterior abdominal excision of the rectum with a laparoscopic approach+ colonic reservoir and hand sewn coloanal anastomosis. Ileostomy closure was performed in both patients at 3 months after surgery, and they demonstrated good early and late postoperative outcomes. In summary, laparoscopic-assisted bowel resection may be a good option for surgical management of diffuse cavernous hemangioma of the rectum.  相似文献   
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BACKGROUND: Strictureplasty is an alternative surgical procedure for Crohn's disease, particulary in patients with previous resections or many intestinal stenosis. AIM: To analyze surgical complications and clinical follow-up in patients submitted to strictureplasty secondary to Crohn's disease. METHODS: Twenty-eight patients (57.1% male, mean age 33.3 years, range 16-54 years) with Crohn's disease and intestinal stenosis (small bowel, ileocecal region and ileocolic anastomosis) were submitted to strictureplasty, at one institution, between September 1991 and May 2004. Thirteen patients had previous intestinal resections. The mean follow-up was 58.1 months. A total of 116 strictureplasties were done (94 Heineke-Mikulicz--81%, 15 Finney--13%, seven side-to-side ileocolic strictureplasty--6%). Three patients were submitted to strictureplasty at two different surgical procedures and two in three procedures. RESULTS: Regarding to strictureplasty, postoperative complication rate was 25% and mortality was 3.6%. Early local complication rate was 57.1%, with three suture leaks (10.7%) and late complication was present in two patients, both with incisional hernial and enterocutaneous fistulas (28.6%). Patients remained hospitalized during a medium time of 12.4 days. Clinical and surgical recurrence rates were 63% and 41%, respectively. Among the patients submitted to another surgery, two patients had two more operations and one had three. Recurrence rate at strictureplasty site was observed in 3.5%, being Finney technique the commonest one. Presently, 19 patients had been asymptomatic with the majority of them under medical therapy. CONCLUSION: Strictureplasties have low complication rates, in spite of having been done at compromised site, with long term pain relief. Considering the clinical course of Crohn's disease, with many patients being submitted to intestinal resections, strictureplasties should be considered as an effective surgical treatment to spare long intestinal resections.  相似文献   
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Salivary gland carcinosarcoma, or true malignant mixed tumor, is a very rare and extremely aggressive neoplasm. The clonality and clonal origin of this tumor are discussed controversially. We report a carcinosarcoma of the left parotid gland in a patient who subsequently died of cutaneous, lymphatic and pulmonary metastases. Immunohistochemical staining, electron micrograph analysis, loss of heterozygosity (LOH) analysis and sequence analysis were performed on this tumor with an adenocarcinomatous and a predominant spindle cell-like component. While smooth muscle actin was undetectable by immunohistochemistry, cytoplasmatic myoepithelial structures could be detected by electron microscopy. LOH analysis at 12 genomic locations detected complete deletion of one allele at 17p13.1, 17q21. 3, and 18q21.3 indicating allelic loss in both components of the tumor. Double strand sequencing of the remaining allele of the p53 tumor suppressor gene revealed a wild-type allele. Based on our results, we favor the hypothesis of monoclonal origin of this salivary gland carcinosarcoma with a common stem cell that could be the myoepithelial cell and an inactivated tumor suppressor gene on chromosome 17 other than p53.  相似文献   
998.
BACKGROUND: This study compared the effects of lateral column lengthening and medial translational calcaneal osteotomy on pedal realignment and degeneration of adjacent hindfoot joints noted on radiographs. METHODS: Forty patients who had either a lateral column lengthening (25 feet) or calcaneal osteotomy (17 feet) to reconstruct a flatfoot were retrospectively reviewed as two groups. Six parameters of foot alignment were measured from weightbearing preoperative, early postoperative, and latest followup radiographs. The magnitude of realignment achieved initially and preserved at latest followup was determined for each group. The talonavicular and subtalar joints were graded for radiographic evidence of arthritis before the reconstruction and at latest followup. Demographic information, complication rate, and reoperation associated with each group also were determined by chart review. RESULTS: The group that received a lateral column lengthening demonstrated a greater initial realignment than the group treated with a calcaneal osteotomy. The lengthening group also demonstrated greater realignment than the osteotomized group when they were compared at their respective latest followup. The lengthening group had a higher number of adjacent joints with progression of arthritis. The rate of nonunion was higher with a lateral column lengthening; however, the rate of reoperation after an osteotomy was more than twice that observed after a lateral column lengthening. CONCLUSIONS: The lateral column lengthening group achieved greater realignment initially and maintained correction better over time than the calcaneal osteotomy group while having a lower reoperation rate despite a higher incidence of nonunion and radiographic progression of adjacent joint arthritis.  相似文献   
999.
The use of mammalian oocytes to assess human sperm functionality could be a helpful tool with potential applications in clinical and research programs. In an attempt to develop the pig model, the aim of the present work was to study the interaction between human spermatozoa and pig oocytes at the zona pellucida (ZP), the oolemma, and the ooplasm levels. In vitro matured pig oocytes and human spermatozoa from fertile and low-fertility donors were employed. The induction of the acrosome reaction by the ZP, the ability of the sperm to penetrate the oocyte after coincubation, and the male pronuclear formation after ICSI were evaluated. Human spermatozoa can bind to pig ZP and undergo the acrosome reaction (15% to 58%, depending on the individual); they are not able to fuse with the oolemma but they can decondense and form a male pronucleus (40%-100%) when injected into pig oocytes. In conclusion, this study shows that pig oocytes can be a useful model to assess human sperm functionality.  相似文献   
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