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31.
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The occurrence of granular cell tumor (GCT) in penile tissue is very rare, with only 9 examples reported to date in the English-language literature. Herein, we describe the clinicopathologic and immunohistochemical findings in 9 additional cases. The patients ranged in age from 20 to 60 years (mean, 42 years; median, 40 years) at time of diagnosis. All penile tumors were solitary and arose in the dermis of the penile shaft (n=4), prepuce (n=3), and corona (n=2). A patient had a history of multiple cutaneous GCTs. Duration of symptoms before surgery ranged from 5 days to 2 years with the presence of an asymptomatic nodule representing the most common tumor-related complaint (n=8). The lesions ranged in size from 0.6 to 2.5 cm (mean, 1.5 cm; median, 1.5 cm). Microscopically, the tumors were moderate to highly cellular and were composed of oval to polygonal-shaped cells with abundant coarsely granular eosinophilic cytoplasm. Tumor cells grew in infiltrating nests, cords, and trabeculae and showed neural (n=2) and vessel wall (n=1) invasion or formed a relatively well-marginated solid nodule. Bland cytological features with only rare cells showing nucleomegaly (n=7) or spindling (n=3) were exhibited by 8 tumors. A tumor demonstrated diffuse nuclear atypia and was classified as "atypical." Mitotic activity ranged from 0 to 8 mitoses (mean, 1.4 mitoses) per 50 high-powered fields with no atypical division figures identified. All tumors tested showed moderate to strong immunohistochemical expression of S100 protein (n=6) and low-affinity nerve growth factor receptor (n=5), which was useful for detecting small deposits of tumor and helpful in evaluating surgical margins. Focal tumor cell immunoreactivity was observed for calretinin (4/6 cases) and glial fibrillary acidic protein (1/6 cases). All patients underwent simple (local) excision of their tumor. Complete follow-up data (mean, 21 years; interval range, 0.5-28 years) were available for 6 patients. No patient experienced recurrence or metastatic spread of tumor although surgical margins were microscopically involved by tumor in 5 cases. Benign GCT involving superficial soft tissue of the penis can be adequately managed by a simple excision. Patients with microscopically involved surgical margins can be clinically followed without immediate additional surgery.  相似文献   
33.
Objective To describe the imaging features of spinal pigmented villonodular synovitis (PVNS).Design and patients We retrospectively reviewed 15 cases of pathologically proven spinal PVNS. Patient demographics and clinical presentation were reviewed. Radiologic studies were evaluated by consensus of two musculoskeletal radiologists for spinal location, spinal segments affected, lesion center, detection of facet origin and intrinsic characteristics on radiography (n =11), myelography (n =7), CT (n =6) and MR imaging (n =6).Results Women (64%) were more commonly affected than men (36%) with an average age of 28 years. Clinical symptoms were pain (45%), neurologic (9%) or both (36%). Lesions most frequently affected the cervical spine (53%) followed by the thoracic (27%) and lumbar regions (20%). The majority of lesions (93%) were centered in the posterior elements with frequent involvement of the pedicle (67%), neural foramina (73%), lamina (67%) and facets (93%). No lesions showed calcification. Determination of a facet origin by imaging was dependent on imaging modality and lesion size. A facet origin could be determined in 45% of cases by radiography vs 67% of patients by CT (n=6) and MR (n=6). Large lesions (greater than 3 cm in at least one dimension) obscured the facet origin in all cases with CT and/or MR imaging (44%,n=4). Small lesions (less than 3 cm in any dimension) demonstrated an obvious facet origin in all cases by CT and/or MR imaging (56%,n=5). Low-to-intermediate signal intensity was seen in all cases on T2-weighted MR images resulting from hemosiderin deposition with blooming effect in one case with gradient echo MR images.Conclusions PVNS of the spine is rare. Large lesions obscure the facet origin and simulate an aggressive intraosseous neoplasm. Patient age, a solitary noncystic lesion centered in the posterior elements, lack of mineralization and low-to-intermediate signal intensity on all MR pulse sequences may suggest the diagnosis in these cases. Small lesions demonstrate a facet origin on CT or MR imaging. This limits differential considerations to synovial-based lesions and additional features of a solitary focus, lack of underlying disease or systemic arthropathy, no calcification as well as low-to-intermediate signal intensity on all MR images should allow spinal PVNS to be suggested as the likely diagnosis.The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Departments of the Air Force, Army, Navy or Defense.  相似文献   
34.
40年前创立的青少年糖尿病研究基金会((JDRF)是一个致力于通过支持研究来探寻1型糖尿病(TIDM)及其并发症治疗方法的组织.20世纪70年代有学者提出,TIDM和2型糖尿病(T2DM)的发病机制有根本的不同,T1DM与主要组织相容性复合体的人白细胞抗原(HLA)有独特相关性,有胰岛细胞自身抗体.  相似文献   
35.
Strangulation in child abuse: CT diagnosis   总被引:2,自引:0,他引:2  
Bird  CR; McMahan  JR; Gilles  FH; Senac  MO; Apthorp  JS 《Radiology》1987,163(2):373-375
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients.  相似文献   
36.
Taylor  GA; Fitz  CR; Miller  MK; Garin  DB; Catena  LM; Short  BL 《Radiology》1987,165(3):675-678
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis.  相似文献   
37.
Incidence of red cell antibodies after multiple blood transfusion   总被引:3,自引:0,他引:3  
A retrospective study was performed to estimate the frequency of alloimmunization against red cell (RBC) antigens in a multiply transfused group. Patients (n = 186) were studied who had received at least six blood transfusions during a period of at least 3 months. Some 6944 units of blood were transfused. One hundred forty patients had hematologic disorders. The patients' sera were investigated every 3 months with indirect antiglobulin tests and enzyme-treated RBCs. Twenty-two patients (11.8%) made 33 antibodies. Seven patients made more than one antibody. Eight of the 22 patients (36.4%) made their first antibody before or at the 10th transfusion. The risk of immunization increased with the number of transfusions. Influence of gender and age was not demonstrable. Nor was a relationship demonstrated between blood transfusion reactions and RBC antibody formation; no delayed hemolytic transfusion reactions occurred. Anti-E was demonstrated in 12 patients and anti-K in 15. When the gene frequencies were taken into account, it appeared that anti-E was made by 11.5 percent of E-negative patients, most of whom were immunized after an estimated three transfusions with E-positive blood. Anti-K was made by 8.7 percent of the K-negative patients, after an estimated 2.1 units of K-positive blood. It might be desirable to match red cell units for the E and K antigens in patients at relatively high risk. These are primarily patients who have already formed an antibody and are going to receive many transfusions and women of childbearing age who are to receive more than 4 units of blood.  相似文献   
38.
39.
The clinicopathologic features of five cases of a fibrocartilaginous mass developing in the nuchal ligament, the nuchal fibrocartilaginous pseudotumor, are described. Only six examples of this lesion were previously reported in the English-language medical literature. The lesions clinically manifested in five adults (3 women, 2 men) ranging in age from 22 to 46 years (mean, 37 yr). The process presented as a nodular mass that was asymptomatic in three patients and accompanied by vague neck pain or stiffness in the remaining two. Three patients related a history of head and neck trauma that preceded the discovery of the tumor. All of the tumors were situated in the deep soft tissue overlying the posterior aspect of the lower cervical vertebrae. The five patients were managed by complete local excision. The tumors measured 1.3 to 3.0 cm. in greatest dimension (mean, 2.5 cm.). Microscopically, the lesion consisted of a poorly delineated, nodular proliferation of moderately cellular fibrocartilaginous tissue arising within the substance of the nuchal ligament and extending into the surrounding soft tissues. No cytologic atypia or mitotic activity was identified. Follow-up data from four of the cases in this study (range, 10-324 mo) and four previously reported examples with follow-up (range, 3-12 mo) show no evidence of recurrent or persistent disease after simple excision. The nuchal fibrocartilaginous pseudotumor is a benign lesion caused by fibrocartilaginous metaplasia of the lower portion of the nuchal ligament, probably as a result of localized trauma or chronic mechanical stress.  相似文献   
40.
Myers  CR; Myers  JM 《Carcinogenesis》1998,19(6):1029-1038
The NADPH-dependent reduction of chromium (VI), a known carcinogen, by hepatic microsomes was very similar for all five humans examined, with an apparent Km for chromate of 1.04-1.68 microM, and a Vmax of 10.4- 10.7 nmol/min/mg protein. Inhibitor studies indicate no role for cytochrome P450s, but a prominent role for flavoproteins, which could include P450 reductase, flavin-containing mono-oxygenase and cytochrome b5. Relative to anaerobic conditions, Cr(VI) reduction was inhibited only 26-37% by room air, which indicates that human microsomal Cr(VI) reduction could still proceed at significant rates, even in tissues with high O2 tensions. Studies with lung microsomes from one human exhibited Vmax and Km values that were two-thirds lower and 2.8-fold greater, respectively, than those of hepatic microsomes from the same individual; other Cr(VI)-reducing parameters were similar for lung and liver. Various forms of exogenous iron, when present at 0.76-6.3 microM, markedly enhanced both liver and lung microsomal rates and Vmax of Cr(VI) reduction, but did not significantly alter the other Cr(VI)- reducing parameters (Km, effects of O2 and inhibitors). These iron levels were 3.1- to 26-fold lower than the initial Cr(VI) concentration, which suggests that iron is serving a catalytic role. The ratio of human microsomal Cr(VI) reduction rates under aerobic versus anaerobic conditions remained fairly constant, regardless of iron concentration. Small increases in intracellular iron could therefore lead to large increases in the rate and extent of microsomal Cr(VI) reduction. Individuals that are simultaneously exposed to Cr(VI) and to agents that increase intracellular iron could therefore be at potentially greater risk for Cr(VI) toxicity and carcinogenicity.   相似文献   
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