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941.
Abstract: Pseudoangiomatous stromal hyperplasia (PASH) is a benign, localized fibroblastic and myofibroblastic overgrowth that occurs almost exclusively in premenopausal women as a painless, palpable intramammary mass. The lesion has a pale, fibrous, and homogeneous cut surface, is typically well circumscribed, and may have a diameter of 2.0–15 cm. Its ramifying slits lined by flattened myofibroblastic cells are apt to be mistaken for vascular spaces, leading to an erroneous diagnosis of angiosarcoma. The etiology of the condition is unknown, but a relationship to myofibroblastoma has been postulated. Hormonal factors, too, are thought to play a developmental role. The potential for PASH to create a palpable breast mass has been only quite recently advanced in the medical literature, and it has evidently not been reported in the nipple.  相似文献   
942.
A 34-year-old female visited our hospital because of epigastralgia. We performed an upper gastrointestinal x-ray examination, and both conventional endoscopy and dye-spraying endoscopy (indigo-carmine contrast method). We diagnosed early gastric lymphoma which simulated Borrmann 3 type gastric cancer with IIb type early gastric cancer on the middle body and reactive lymphoreticular hyperplasia (RLH) of cobble stone-like granular pattern by endoscopic appearance on the lower body. Although dye-spraying endoscopy showed the details of the mucosa, it was very difficult to diagnose the lesions correctly by gross appearance alone. Because gastric lymphoma arises from the mucosal or submucosal layer and spreads in the mucosa diffusely, ultrasonic visualization by echo-endoscopy might be useful in the diagnostic procedure. We report a case of early gastric lymphoma coexisting with RLH; both lesions showed uncommon endoscopic features.  相似文献   
943.
True thymic hyperplasia (enlarged gland composed of histologically unremarkable cortical and medullary parenchyma) and lymphoid hyperplasia (medullary lymphoid follicles in the clinical setting of autoimmunity) usually develop as independent pathologic processes. We reviewed the clinical features and gross and microscopic pathology of 2 hyperthyroid patients with features of both thymic hyperplasia and lymphoid hyperplasia. The diagnosis of thymic hyperplasia was supported by thymic weights greater than two standard deviations above the mean weight for age and histologic evidence of expanded cortical and medullary parenchyma. The diagnosis of lymphoid hyperplasia was supported by the increased number and size of medullary lymphoid follicles and the association with Grave's disease. This unusual combination results from two separate pathogenic mechanisms operating simultaneously in hyperthyroid patients. Elevated thyroid hormones directly stimulate the proliferation of thymic epithelium, producing thymic hyperplasia. The immune abnormalities underlying Grave's disease can also result in lymphoid hyperplasia of the thymus.  相似文献   
944.
Index     
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945.
We analysed a large series of axillary lymph nodes, with and without metastases following radical mastectomy for breast cancer. We found left/right asymmetry in numbers of lymph nodes, and also asymmetry of lymph node dimensions, which could have been the caused by tumoral antigenic stimulation. The distribution of hyperplastic node patterns differed significantly.  相似文献   
946.
Focal nodular hyperplasia (FNH) is rare in pediatric liver tumor. To investigate the experience in the appropriate management of pediatric FNH, the records of consecutive children who were managed at our institute from 2000 to 2007were reviewed for FNH. There were four males and nine females whose ages ranged from 26 months to 18 years with a mean of 11.7 years. FNH in most children was detected by medical examination for abdominal pain (61.5%) or other symptoms. All the 13 pediatric patients underwent liver resection. There was no operative death or postoperative complications. The children were regularly followed up ranging from 2 to 85 months and they were healthy without recurrence. For pediatric FNH patients with clinical symptoms or indefinite diagnosis, it is suggested that active surgical treatment by hepatectomy should be performed.  相似文献   
947.
948.
949.
Focal nodular hyperplasia (FNH) is a benign, poorly understood hepatic tumor that is rare in children. Although there is no evidence for malignant degeneration, FNH can occur adjacent to a malignancy. Here, the case of a 4-year-old boy with a hepatic mass and history of stage IV neuroblastoma is presented. Initial imaging and core-needle biopsy were consistent with FNH. However, after left lateral segmentectomy, pathologic examination revealed a malignant tumor most consistent with small cell undifferentiated hepatoblastoma as well as 3 foci of FNH in the surrounding parenchyma.  相似文献   
950.
High-intensity focused ultrasound (HIFU) has recently been promoted as a non-invasive treatment option for prostate cancer. This systematic review sought to evaluate the evidence comparing it with standard treatment in patients with localised prostate cancer. The literature review included searches of MEDLINE, EMBASE, the Cochrane Library, annual meetings’ abstracts and websites of evidence-based practice guideline producers. Studies were included if they were randomised controlled trials comparing HIFU with current management approaches, or were meta-analyses, systematic reviews or practice guidelines addressing HIFU. No randomised controlled trials or meta-analyses were identified. Seven systematic reviews and two practice guidelines were identified; neither contained randomised controlled trials. Adjusting the selection criteria to include case series found 34 clinical studies of HIFU. Twenty-nine evaluated HIFU as the primary treatment and five examined HIFU as salvage treatment for recurrence after radiotherapy. In most studies the outcomes used to determine efficacy were negative biopsy rates or prostate-specific antigen (PSA) levels. Among the 29 studies of HIFU as the primary treatment, negative biopsy rates ranged from 35 to 95% in 21 studies, a PSA nadir of ≤0.5 ng/ml ranged from 55 to 91% in 10 studies and mean PSA nadirs ranged from 0 to 1.9 ng/ml in 17 studies. Five studies reported 5-year disease-free survival rates ranging from 55 to 95%. Among five studies of HIFU as salvage treatment, negative biopsy rates ranged from 73 to 84% in four studies, a PSA nadir of ≤0.5 ng/ml ranged from 57 to 66% in three studies and mean PSA nadirs were 1.97 and 2.38 ng/ml in two studies, respectively. Current evidence on HIFU use in prostate cancer patients is of low quality, rendering it difficult to draw conclusions about its efficacy. Until results from case series are confirmed in prospective studies, the widespread use of HIFU is not supported.  相似文献   
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