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The stroma of fibroadenoma and phyllodes tumor usually consists of fibroblastic proliferation. Rarely the stroma contains bundles of smooth muscle. Pseudoangiomatous hyperplasia of the mammary stroma has been described in fibroadenomas. However, true benign vascular stroma has not been reported. We report a case of a 34-year-old Chinese woman who presented with a large mass occupying the entire left breast. Left mastectomy was performed and showed a large, well-circumscribed, lobulated, rubbery-firm tumor measuring 13 x 10 x 6 cm. Microscopic examination revealed a fibroepithelial tumor formed by an organoid pattern of ductal structures with a very striking stromal appearance composed of extensive vascular proliferation and that demonstrated strong immunoreactivity for CD31, CD34, and Factor VIII. Ultrastructural examination revealed intercellular junctions, basal lamina, pinocytotic vesicles, and Weibel-Palade bodies in the cells lining the vascular spaces, confirming their endothelial nature. These findings rule out the diagnosis of pseudoangiomatous hyperplasia. The patient developed local recurrence a year later, and the resection showed malignant phyllodes tumor with ductal carcinoma in situ.The extensive vascular stroma noted in the primary tumor may have played a role in the malignant transformation of the epithelial and stromal components in this tumor. 相似文献
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Jeffrey R. Rubin MD Enrique Labadie MD Gary Anderson BS James Persky MD Jerry Goldstone MD 《Annals of vascular surgery》1988,2(2):127-132
This study evaluates the effect of blood volume and hematocrit changes on brain tissue during temporary global ischemia. Normal saline was administered intravenously to 55 gerbils to achieve hypo-, normo-, and hypervolemic hemodilution and uniform 30% hematocrit reduction. Each group had unilateral carotid artery ligation and temporary (20 minute) contralateral carotid occlusion. After ten days or death, brains were harvested, preserved in formalin, sectioned in a manner which provided adequate samples of both cortex and hippocampus, and stained with H&E and luxol fast blue. They were then examined and staged microscopically for white and gray matter infarction, edema, and neuronal injury and loss. Histologic studies were performed in a randomized and blinded manner and were classified by one of four categories: normal, minimal, moderate, and severe changes. Three of ten (30%) controls survived ten days but had severe neuronal loss, minimal cerebral edema and a minimal to moderate number of white matter strokes. Survival was best in animals treated with hypovolemic hemodilution (43%). Other rates were: normovolemic (33%), controls (30%), and hypervolemic (8.3%). The degree of brain tissue damage was markedly less in the normovolemic group. In this model, normovolemic hemodilution followed by hypovolemic hemodilution offered the best overall cerebral protection during global ischemia. 相似文献
56.
Lymphoma presenting as a salivary gland mass 总被引:2,自引:0,他引:2
M A Schusterman M S Granick E R Erickson E D Newton D C Hanna R W Bragdon 《Head & neck surgery》1988,10(6):411-415
A retrospective review of 36 cases of lymphoma presenting as a salivary gland mass was conducted over a 34-year period. A significant increase in the occurrence of lymphoma was noted in proportion to other salivary gland tumors (P less than 0.01, chi 2 analysis: 1954-1972, 11 of 714 (1.5%); 1973-1979, 9 of 201 (4.5%); 1980-1987, 16 of 265 (6.0%). The mean age was 61 years, sex distribution was equal, and 75% occurred in the parotid. Only 42% presented with signs or symptoms other than a painless mass. Glandular excision was done in early stages of the disease while biopsy was done at later stages. Frozen section analysis was accurate in all but one case and was useful in determining if biopsy were adequate. All patients were definitively treated with chemotherapy and/or radiotherapy. Several instructive points are apparent. Any patient presenting with an isolated salivary gland mass can have a lymphoma. There has, in fact, been a significantly increasing proportion of salivary gland lymphoma among the various salivary gland tumors in our patient population. In contrast to other salivary gland tumors, surgery is reserved for diagnosis and not for treatment. A lymph node biopsy may be sufficient to establish a diagnosis, in which case, glandular excision is unnecessary. Most of the patients presented with an asymptomatic isolated salivary gland mass. The presence of adjacent adenopathy, a rubbery feel to the mass, and the intraoperative appearance were the most suggestive signs of lymphoma. Frozen section analysis is helpful in determining the appropriate extent of surgery and is recommended. 相似文献
57.
Bernhard Fink Vanlal Thanzami Hanna Seydel John T Manning 《American journal of human biology》2006,18(6):776-782
The ratio of the length of the second and fourth digits (2D:4D), a putative proxy of prenatal testosterone (PT), is correlated with measures of physical fitness. The relationship between the organizing effect of PT on physical fitness is likely to arise as a response to intrasexual male competition for females. Physical strength is also likely to be important in intrasexual conflict, but nothing is known concerning the relationship between 2D:4D and strength. The strength of an individual is strongly influenced by body size, and 2D:4D is strongly dependent on ethnicity. We present evidence that strength, as measured from hand-grip strength, is related to 2D:4D in samples from two ethnic groups (52 Caucasian men from Germany, and 88 Oriental Mizos men from northeast India) which differed markedly in size. We found that 1) the German men were heavier and stronger, but had higher 2D:4D (lower PT) than the Mizos men; 2) a median split for grip strength into low (LGS) and high (HGS) groups showed that for right-hand 2D:4D (but not left-hand 2D:4D), the LGS men had higher 2D:4D than the HGS men; and 3) the relationships between right 2D:4D and grip strength were independent of ethnicity, age, height, and weight. Measures of grip strength correlate strongly with strength in other muscle groups, so we conclude that PT may have an early organizing effect on strength in men, and this is likely to be widespread in human groups. 相似文献
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Splints have a variety of uses in the hand and wrist including the treatment of both soft tissue and bony injuries. They are the mainstay of treatment of many hand and wrist conditions. A sound understanding of the underlying anatomy and biomechanical principles is essential to ensure good practice. Risks associated with their use have been discussed to enable clinicians to appropriately prescribe, design and apply splints. 相似文献
60.
Dr. A. Belluzzi MD C. Brignola MD M. Campieri MD E. P. Camporesi BS P. Gionchetti MD F. Rizzello MD C. Belloli MD G. De Simone MD S. Boschi MD M. Miglioli MD L. Barbara MD 《Digestive diseases and sciences》1994,39(12):2589-2594
Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods. 相似文献