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Steven Kaddu H. Peter Soyer Ingrid H. Wolf Helmut Kerl 《Journal of cutaneous pathology》1997,24(4):228-234
We report on 9 patients with pilomatricomas that showed unusual histopathologic features. Our patients were mainly elderly individuals (age range 42 to 88 years; mean age 70.1 years) who presented solitary cutaneous nodules situated on the head and neck (7 neoplasms), upper arm (1 neoplasm), and back (1 neoplasm). All the lesions were treated by simple excision. Follow-up data available in 7 of the 9 patients (mean follow-up, 17 months) revealed local recurrences in 1 patient whose lesion recurred 3 times. No lymph node involvement or distant metastases were recorded in any of our cases. Histopathologically, most neoplasms were characterized by a relatively large lesion in the clermis that in some cases showed extension to the subcutis. Each lesion was predominantly composed of a lobular proliferation of basaloid cells in association with adjacent focal areas containing eosinophilic, cornified material with shadow cells. In some cases, relatively large areas of shadow cells were present, whereas, in others only small foci of shadows cells were observed. Cytomorphologically, the basaloid cells showed features of matrical and supramatrical cells of a normal hair follicle and exhibited variable nuclear atypia and mitotic figures. The overall architectural pattern of the neoplasms was different from that of large fully developed stereotypical pilomatricomas that maintain a cystic character with basaloid cells predominantly aligned at the periphery. Based on the histopathologic findings, namely the presence of a large, lobular proliferation of basaloid cells in association with small to large foci of shadow cells, we interpreted these neoplasms to be a distinctive proliferative variant of pilomatricoma and propose the designation "proliferating pilomatricoma." Proliferating pilomatricomas should be differentiated from the recently described matricoma, basal-cell carcinoma with matrical differentiation, and matrical carcinoma (pilomatrical carcinoma). 相似文献
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Dr. med. Dr. med. dent. Christof Holberg Anne-Kathrin Heine Philipp Geis Katja Schwenzer Ingrid Rudzki-Janson 《Journal of orofacial orthopedics》2005,66(2):122-134
BACKGROUND AND AIM: The goal of this study was to analyze the validity and prediction accuracy of a newly-developed procedure for three-dimensional soft tissue prediction based on Finite Element Method, and to compare the results with prediction produced using an existing two-dimensional prediction program (Dentofacial Planner Plus). PATIENTS AND METHODS: In twelve patients who underwent combined surgical-orthodontic treatment, profile prediction was generated using both procedures preoperatively and then compared at predefined measurement points with the patient's actual postoperative soft tissue status. RESULTS: The deviations observed depended on the facial region, whereby the prediction errors for both procedures were much greater in the lower facial third than in the midfacial third. Calculating in all the measurement points, the mean horizontal prediction error was 0.32 mm for the Finite Element Method and 0.75 mm for the Dentofacial Planner Plus. Overall, we were able to demonstrate the new procedure's superior validity and quality of visualization. In addition to profile prediction, the procedure allows a differentiated three-dimensional assessment of esthetically important regions such as the cheeks, nasolabial folds and the nasal wings. Additional X-radiation is not necessary in this risk-free and stress-free procedure. CONCLUSION: Three-dimensional soft tissue prediction employing finite element modeling is a useful aid for implementing esthetically-optimized treatment planning. 相似文献
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Jenny Andersson Barbro Linderholm Jonas Bergh Goran Elmberger 《Applied immunohistochemistry & molecular morphology》2004,12(1):14-20
We have studied the intratumor HER-2/neu heterogeneity in 78 consecutive and population-based primary invasive breast carcinomas. Within the invasive component, heterogeneity was detected in only 1 of 78 tumors. In 48 tumors (62%), we found both in situ and invasive components in analyzed tissue sections. Twelve of these 48 tumors had a difference of at least 2 arbitrary units in the in situ compared with the invasive part of the tumor with regard to the HER-2/neu status analyzed by HercepTest (immunohistochemistry). Eight of these 12 tumors were reanalyzed with fluorescent in situ hybridization and immunohistochemistry with and without a new Automated Cellular Imaging System. In this limited material, immunohistochemistry in combination with the Automated Cellular Imaging System seemed to have a better correlation with fluorescent in situ hybridization than immunostaining analyzed manually. In conclusion, HER-2/neu expression is not seldom heterogeneous in invasive compared with in situ components within a tumor. This finding should be considered in the choice of evaluation method. To avoid heterogeneity as a confounding factor in HER-2/neu analyses, detection methods such as immunohistochemistry and fluorescent in situ hybridization, which can provide evaluation in a preserved tissue architecture, should be used. Perhaps the intratumor HER-2/neu heterogeneity can explain some of the unexpected failures of trastuzumab therapy. 相似文献
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Martin Klomp Peter M. Van den Bergh Frits J. H. Harinck 《Child & youth care forum》1997,26(5):343-355
In child and youth care in the Netherlands, systematic planning of treatment is more and more considered to be a condition
for effective and well founded treatment. Although workers are convinced of the benefits of treatment plans, treatment planning
is not yet a natural and integrated part of residential care. There are several pressure points. In this article a model of
treatment planning will be presented that contributes to an answer to these pressure points. The theoretical bases and the
practical implications of this model will be discussed. 相似文献
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Ingrid Gouldsborough Nick Ashton 《Clinical and experimental pharmacology & physiology》1998,25(12):1024-1031
1. The aim of the present study was to compare electrolyte handling in naturally reared neonatal spontaneously hypertensive rats (SHR) with those reared by a Wistar-Kyoto (WKY) rat foster mother (denoted SHRX), as cross-fostering SHR pups to a WKY rat dam lowers adult blood pressure in the SHR. 2. The electrolyte content of WKY rat and SHR dams’ milk was determined and electrolyte intake and urinary excretion rates were calculated in both naturally reared and cross-fostered WKY rat and SHR pups. 3. The milk sodium concentration fell in both strains (WKY rat: 31.8 ± 2.0 to 15.2 ± 1.2 mmol/L; SHR 31.9 ± 2.5 to 18.2 ± 1.6 mmol/L; P < 0.001), as did potassium (P < 0.001), over lactation, but there were no differences between strains. Calcium and magnesium concentrations increased (P< 0.001), although SHR dam's milk contained less calcium (P < 0.001) than that of WKY rat dams during the third week of lactation. 4. Spontaneously hypertensive rat pups ingested less milk (P<0.05) than WKY rat pups; therefore, their cumulative sodium intake over postnatal days 4–15 was significantly lower than that of WKY rat pups (WKY rat vs SHR: 84.4 ± 3.6 vs 59.7 ± 2.6 μmol/g bodyweight, respectively; P < 0.05) and fostered SHRX pups (77.7 ± 7.0 μmol/g bodyweight; P < 0.05). Potassium and magnesium intakes were comparable between SHR, WKY rat and SHRX pups, but SHR pups ingested significantly less calcium than either WKY rat pups (136.1 ± 6.4 vs 200.1 ± 9.5p, mol/g bodyweight, respectively; P<0.05) or SHRX pups (200.0 ± 18.0 μmol/g bodyweight; P<0.05). 5. These data show that the neonatal SHR experiences a period of sodium deficiency during the developmental stage when cross-fostering is effective in lowering blood pressure. This is consistent with the reported up-regulation of the renin-angiotensin system observed in SHR at this time and may have a long-term influence on blood pressure. 相似文献
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Summary Bronchus stump insufficiency following lung resection, with an average incidence of 4%, is a serious complication which carries a mortality of up to 90%. Operative transthoracic approaches have been largely unsatisfactory because of the high operative risk and rapidly spreading infection. In an experimental study on 18 pigs, endoscopic occlusion of infected bronchus stump fistulae was achieved with fibrin sealant (1 ml, 500 units/ml thrombin, 3500 units/ml aprotinin) applied via a flexible bronchoscope. During autopsy, all bronchus stump fistulae were found to have healed after the second postoperative week. Transitory local abscesses of the pleura could be prevented by high-dose systemic antibiotic therapy for 5 postoperative days but not by antibiotics added to the fibrin sealant. This endoscopic method has already been performed successfully in 3 clinical cases; additional sclerotherapy with (2–3 ml Ethoxysclerol applied around the fistula orifice was carried out before fibrin sealing to stimulate fibrosis. Endoscopic controls demonstrated fistula closure by granulation tissue after 2 weeks. This procedure could become the method of choice for infected postoperative fistulae of the bronchus stump and should be attempted in any case before operative approaches are considered. 相似文献