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11.
We present a new concept after Schultheis which is based on the results of experimental studies on cell cultures. Local chemoembolization in liver tumours including liver metastases is usually performed via the angiographic route. Embolisation of the most peripheral branches of the hepatic artery prevents early formation of collateral vessels. The method also comprises the additional infusion of cytostatic agents via the portal vein. The procedure is usually repeated after an interval of about four weeks. In this paper we will describe our method in liver metastases and present the preliminary results obtained from 19 patients treated to date. 相似文献
12.
With regard to disturbances of the iron metabolism, porphyria cutanea tarda (PCT) is most frequently accompanied by liver siderosis. In 74 out of 88 patients suffering from PCT (84%), we found histochemical evidence of liver siderosis. These patients showed a significantly higher incidence of HLA A3--which has been proved to be associated with hemochromatosis--than those without liver siderosis (39.2% vs. 7.1%). With part of the PCT patients, disorders of the iron metabolism related to the HLA system (A3) might contribute to the manifestation of the disease. We discuss PCT as the result of the combined action of several predisposing genetic markers and exogenic factors. 相似文献
13.
In a prospectively randomized study we used two different ways of drainage of the sacral space after an abdomino-perineal-resection of the rectum. One group with 25 patients had a drainage anteriorly through the abdominal wall, the other 25 patients got a drainage posteriorly through the buttocks. In each case we used two closed silicone-drainage-systems without active suction. In 60% of the anterior and in 50% of the posterior drained cases we saw an unaffected primary healing of the sacral wound. There was no significant difference. The patients felt the anterior way of drainage to be more convenient. Contamination of the sacral space by disrupture of the rectum during the operation was followed by a sacral abscess in 50%. 相似文献
14.
15.
C A Sander E S Jaffe F C Gebhardt T Yano L J Medeiros 《The American journal of surgical pathology》1992,16(3):300-305
A 19-year-old woman presented with a large mediastinal mass, histologically shown to be malignant lymphoma of lymphoblastic type (LBL). Immunophenotypic and gene rearrangement analysis unequivocally demonstrated that the neoplasm was of B-cell lineage. The neoplastic cells expressed terminal deoxynucleotidyl transferase, the pan-B cell antigens CD19, CD20, and CD22, and were negative for immunoglobulins and numerous T-cell antigens tested. Southern blot analysis showed rearrangement of one allele of the immunoglobulin heavy chain gene while the immunoglobulin kappa and T-cell receptor beta chain genes were in the germline configuration. Thus, the immunophenotypic and molecular findings in this case correspond to an early stage of B-cell differentiation, the pre-pre B-cell stage as has been named by others. In contrast with LBL of immature T-cell lineage, precursor B-cell LBLs involving the mediastinum are truly rare. Occasional cases have been reported that have arisen elsewhere and subsequently involved the mediastinum at time of relapse or tumor progression. Well-documented examples of immature B-cell LBL arising in the mediastinum are virtually unreported. The site and cell population giving rise to this neoplasm is unknown. However, origin from precursors of normal thymic medullary B cells is proposed as one possibility. 相似文献
16.
17.
目的:研究低氧时小鼠肺组织中低氧诱导因子-1α(HIF-k)表达的变化。方法:实验用雄性小鼠,低氧仓浓度分别为10%、7%、5%。用免疫荧光组织化学技术及共聚焦显微术,检测小鼠在低氧条件下肺组织中HIF-1α表达的变化。结果:正常组小鼠肺组织HIF-1α无表达,低氧组HIF-1α表达增加,且随低氧时间的延长及低氧强度的增加而增强。结论:低氧可诱导小鼠肺组织中HIF-1α的表达增强,(HIF-k)可能参与肺组织细胞凋亡的发生。 相似文献
18.
c-Fos-dependent induction of the small ras-related GTPase Rab11a in skin carcinogenesis 总被引:1,自引:0,他引:1
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Gebhardt C Breitenbach U Richter KH Fürstenberger G Mauch C Angel P Hess J 《The American journal of pathology》2005,167(1):243-253
Malignant transformation of mouse skin by tumor promoters and chemical carcinogens, such as the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), is a multistage process leading to the formation of squamous cell carcinomas. It has been shown that mice lacking the AP-1 family member c-Fos exhibit an impaired transition from benign to malignant skin tumors. Here, we demonstrate enhanced expression of the small Ras-related GTPase Rab11a after short-term TPA treatment of mouse back skin. Expression of Rab11a in vivo and in vitro critically depended on c-Fos, because TPA application to the back skin of c-Fos-deficient mice and to mouse embryonic fibroblasts did not induce Rab11a mRNA or protein expression. Moreover, dexamethasone, which is a potent inhibitor of AP-1-mediated transactivation that exhibits anti-inflammatory and anti-tumor promoting activities, inhibited TPA-induced expression of Rab11a. Within the Rab11a gene promoter, we identified a functional AP-1 binding element that exhibited elevated c-Fos binding activity after TPA treatment of keratinocytes. Enhanced expression was not restricted to chemically induced mouse skin tumors but was also found in tumor specimens derived from patients with epithelial skin tumors. These data identify Rab11a as a novel, tumor-associated c-Fos/AP-1 target and may point to an as yet unrecognized function of Rab11a in the development of skin cancer. 相似文献
19.
Nutrition and immunological responsiveness: T-cell function in the offspring of lipotrope- and protein-deficient rats 总被引:1,自引:1,他引:1
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The progeny of mothers subjected to marginal lipotrope or moderately low protein diets exhibit deficient humoral immune responses. Serum antibody titres and numbers of antibody-forming cells to sheep erythrocytes (SRBC) are lower in the offspring of mothers whose diets were limited in either percentage protein or percentage lipotropes than in offspring whose mothers were fed a complete diet. Immune lymphocyte stimulation by SRBC antigens was marginal and not measurably different between the progeny of malnourished mothers and controls.
The in vitro response of spleen cells from offspring of nutritionally deprived mothers to the T-cell mitogen phytohaemagglutinin (PHA) is considerably less than that of controls. Thymus cells from marginal lipotrope offspring respond well to PHA, suggesting that PHA-reactive cell migration may be inhibited in these animals.
These results, obtained using a T-dependent antigen (SRBC) and a T-dependent mitogen (PHA), support the conclusion that maternal dietary deficiency can adversely affect T-cell function in rat offspring.
相似文献20.
Mehnert P Malchaire J Kampmann B Piette A Griefahn B Gebhardt H 《European journal of applied physiology》2000,82(1-2):52-60
The prediction of the mean skin temperature used for the Required Sweat Rate index was criticised for not being valid in
conditions with high radiation and high humidity. Based on a large database provided by 9 institutes, 1999 data points obtained
using steady-state conditions, from 1399 experiments and involving 377 male subjects, were used for the development of a new
prediction model. The observed mean skin temperatures ranged from 30.7 °C to 38.6 °C. Experimental conditions included air
temperatures (T
a) between 20 and 55 °C, mean radiant temperatures (T
r) up to 145 °C, partial vapour pressures (P
a) from 0.2 to 5.3 kPa, air velocities (v
a) between 0.1 and 2 m/s, and metabolic rates (M) from 102 to 620 W. Rectal temperature (T
re) was included in the models to increase the accuracy of prediction. Separate models were derived for nude (clothing insulation,
Icl, ≤0.2 clo, where 1 clo=0.155 m2 · °C · W−1, which is equivalent to the thermal insulation of clothing necessary to maintain a resting subject in comfort in a normally
ventilated room, air movement=10 cm/s, at a temperature of 21 °C and a humidity of less than 50%) and clothed (0.6 ≤ Icl ≤ 1.0 clo) subjects using a multiple linear regression technique with re-sampling (non-parametric bootstrap). The following
expressions were obtained for nude and clothed subjects, respectively: T
sk=7.19 + 0.064T
a + 0.061T
r + 0.198P
a− 0.348v
a + 0.616T
re and T
sk=12.17 + 0.020T
a + 0.044T
r + 0.194P
a − 0.253v
a + 0.0029M + 0.513T
re. For the nude and clothed subjects, 83.3% and 81.8%, respectively, of the predicted skin temperatures were within the range
of ±1 °C of the observed skin temperatures. It is concluded that the proposed models for the prediction of the mean skin temperature
are valid for a wide range of warm and hot ambient conditions in steady-state conditions, including those of high radiation
and high humidity.
Accepted: 7 February 2000 相似文献