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排序方式: 共有6867条查询结果,搜索用时 15 毫秒
61.
62.
Kyriakos Chatzopoulos Sotiris Sotiriou Andrea R. Collins Panagiotis Kartsidis Alessandra C. Schmitt Xianfeng Chen Khashayarsha Khazaie Michael L. Hinni Colleen A. Ramsower Matthew A. Zarka Samir H. Patel Joaquin J. Garcia 《Head and neck pathology》2021,15(2):509
The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-β, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01229-w) contains supplementary material, which is available to authorized users. 相似文献
63.
Fatima Hammoud Julie Kirschner Méline Carré Wolfgang Paulus Anna-Maria Cristadoro Michael Schmitt Jacques Lalevée 《Macromolecular chemistry and physics.》2023,224(19):2300237
Frontal polymerization (FP) has attracted increasing interest in recent years in various applications. This polymerization method can be very promising for the polymerization of thick materials with high fillers content in the range of 50–80% (weight) by local application of a reasonable amount of energy. In this work, recent advances in controllable and predictive behavior for photoinduced frontal photopolymerization are reported. Here, tert-butyl peroxybenzoate (Luperox-P) is selected to initiate thermal polymerization at depth because its high polymerization ability and its decomposition temperature is in a promising range, i.e., neither extremely high (monomer decomposition) nor very low (storage stability issues). Thermal imaging experiments are used to follow the temperatures in the samples in real time. The number of cured layers and the depth of cure are also determined. This paper investigates various factors such as the contents of both photo and thermal initiators, the light intensity, the fiber contents, the irradiation time, etc., resulting in a statistical design of experiments with the factors: 1) content of Luperox P and 2) the irradiation time used to investigate the influence on photoinduced frontal polymerization. Markedly, FP appears to be fully controllable for a storage-stable, tunable 1K system. 相似文献
64.
T. Martin C. Schmitt J.-C. Weber J. L. Pasquali M. Weber J. Flament J. Sahel M. M. Tongio 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(5):269-274
Background: Endogenous posterior uveitis (PU) can be associated with systemic diseases, and certain forms have strong association with HLA antigens. Much less is known regarding intermediate uveitis (IU). The purpose of this study was to determine whether IU is associated with the HLA system and whether it can be associated with systemic symptoms.Methods: In 179 consecutive patients consulting for uveitis, a detailed history was obtained and a physical examination performed. HLA typing for 71 HLAA, B, DR and DQ antigens, laboratory tests, and radiography of the chest, sinuses, and sacroiliac joints were systematically performed.Results: Thirty-two patients (18%) had IU; 51 (28.5%) had PU and constituted our internal control group. Nine of the patients with IU (28%) had the HLA-A28 antigen, compared with 8.1 % of a healthy control population and 8.6% of the patients with PU (P < 0.001). An associated disease was found in four patients with IU (12.5%) (none was HLA-A28) and in 45% of the patients with PU (P < 0.01). Some 67% of HLA-A28 patients with IU had arthralgias affecting the knee(s), compared with 17% of non-HLA-A28 patients and 18% of patients with PU (P<0.05 and P<0.01 respectively); 55% had gonalgias and hypocomplementemia compared with 9% and 2% respectively (P < 0.01 and P < 0.001).Conclusions: IU is significantly associated with HLA-A28; patients having this antigen may represent a subset of the disease characterized by an increased prevalence of arthralgias and hypocomplementemia. 相似文献
65.
Triple approach for diagnosis and grading of meningiomas: Histology,morphometry of Ki-67/feulgen stainings,and cytogenetics 总被引:5,自引:0,他引:5
H. Kolles I. Niedermayer Ch. Schmitt W. Henn R. Feld W. I. Steudel K. D. Zang W. Feiden 《Acta neurochirurgica》1995,137(3-4):174-181
Summary With regard to meningioma grading and the recently introduced atypical meningioma, we evaluated 160 cases retrospectively by conventional histology and image analysis. For that, the cell nuclei were stained with a Ki-67 (MIB1)/Feulgen-method on paraffin sections, thus enabling the assessment of both the Ki-67 proliferation index and nuclear morphometric features, such as tumour cell arrangement, nuclear pleomorphism, and cellularity.It could be demonstrated that the Ki-67 proliferation index is the most important criterion for distinguishing anaplastic meningiomas (WHO grade III) (mean Ki-67 index: 11%) from those of common type (WHO grade I) (mean Ki-67 index: 0.7%). The parameter for the relative volume weighted mean nuclear volume is another valuable morphometric feature. The atypical meningioma (WHO grade II) which should represent an intermediate category between common type and anaplastic meningiomas is characterized by a mean Ki-67 proliferation index of 2.1%. Common type meningiomas which comprise almost 50% of the cases of this series have a relapse rate of 9%. Atypical and anaplastic meningiomas recurred in 29% and 50%, respectively. Since the term atypical meningioma is confusing in the context of tumour grading, the term intermediate type meningioma is proposed.Furthermore, the results of cytogenetic analyses of 142 cases of this series were evaluated and compared with the meningioma grades. Thereby, 25 cases disclosed, independent of the typical loss of one chromosome 22, cytogenetic features assumed to be progression-associated, e.g., the gain or loss of different chromosomes and the deletion of the short arm of one chromosome 1 (hyperdiploidy, increased hypodiploidy, Ip-), when correlated to the histological and morphometric findings or the high relapse rate.For meningioma diagnosis and grading, a practical guideline is proposed based upon histology, morphometry (Ki-67), and cytogenetics. 相似文献
66.
This study uses antiendometrial antibodies as an indicator for follow-up of patients with endometriosis after surgical treatment. This is a prospective study of 32 patients with endometriosis. The patients were used as their own controls. Serum samples were obtained before surgery and 1 month, 3 months, and 6-9 months following surgery. All patients were treated with CO2 laser laparoscopy. Serum concentrations of antiendometrial antibodies decreased significantly at 1 month, 3 months, and 6-9 months following treatment in each group. There was no correlation between baseline concentration of antibodies and stage of the disease. This study confirms the value of using antiendometrial antibodies as an indicator for follow-up of endometriosis patients. Surgical treatment with CO2 laser laparoscopy is effective in lowering the antigenic effect of the disease in these patients. This beneficial effect is maintained for up to 9 months after treatment. 相似文献
67.
Perlick L Möller G Wallny T Schmitt O 《Zeitschrift für Orthop?die und ihre Grenzgebiete》1999,137(6):503-507
INTRODUCTION: Diagnosis of Guillian-Barré Syndrome usually is not difficult, but diagnostic failure occurs for the variable initial presentation. Diagnosis is based on physical examination showing loss of motor strength in more than one limb and loss of deep tendon reflexes. Ventilatory assistance, pharmacologic maintenance of cardiovascular homeostasis, corticosteroids, IgG and plasma exchange are the dominant therapeutic measures. CASE: This article reports on a case of a 59-year old surgeon suffering from degenerative disc disease in the lumbar spine. The patient developed a severe course of the Guillian-Barré Syndrome with persisting motor weakness of the legs. CONCLUSION: If the primary problem at presentation is limb and back pain the pathology appears to be in the musculoskeletal rather than in neurological system. The awareness of this presentation of Guillian-Barré-Syndrome will eliminate delay in diagnosis. 相似文献
68.
69.
P Lagiou A Trichopoulou H K Henderickx C Kelleher I U Leonhauser O Moreiras M Nelson A Schmitt W Sekula K Trygg G Zajkas 《European journal of clinical nutrition》1999,53(4):328-332
OBJECTIVE: We have undertaken a study to examine whether Household Budget Survey (HBS)-derived nutritional patterns are related to mortality from diseases with strong nutritional components, namely coronary heart disease, colorectal cancer and cancer of the female breast. DESIGN: Ecological correlation study. In the context of the Data Food Networking projects of the European Union, raw data from the national HBS of 10 European countries were provided. For each of the 10 participating countries, daily food availability per capita around 1990 was calculated. Individual foods were aggregated into 12 major food groups that were linked with the diseases under consideration. Mortality data were available from a World Health Organisation database. We have used a composite score to summarise the postulated influence of diet. SETTING: Ten European countries circa 1990. RESULTS: The correlation coefficients between the composite score and the age-adjusted mortality from each of the studied diseases were: + 0.51 (P approximately 0.14) for colorectal cancer; +0.72 (P approximately 0.02) for female breast cancer; and +0.60 (P approximately 0.07) for coronary heart disease, after adjustment for tobacco smoking. CONCLUSIONS: We conclude that dietary information from HBS is sufficiently reliable to reveal correlations with mortality rates from chronic diseases with fairly strong nutritional roots. HBS data could be used, with little cost, for monitoring secular trends in dietary patterns with a view to their health implications. 相似文献
70.
Lavé T Portmann R Schenker G Gianni A Guenzi A Girometta MA Schmitt M 《The Journal of pharmacy and pharmacology》1999,51(1):85-91
The objective of this work was to assess the pharmacokinetics of napsagatran, a low molecular weight thrombin inhibitor, after intravenous administration in a variety of laboratory animals, and prospectively to help design the first pharmacokinetic studies in man. Napsagatran is actively excreted into the bile and urine of various species and pronounced species-differences in its pharmacokinetics are observed. It is, therefore, an interesting compound to use in tests of the limitations of presently available inter-species scaling methods. The present data suggest that allometric exponent values which are consistent with the values expected for physiological processes and small organic molecules are not necessarily associated with successful predictions in man when active transport processes are involved in the disposition of the compounds. For example, compared with the values observed in man, the clearance (CL), non-renal clearance (CL(nr)) and the volume of distribution at steady state (Vd(ss)) were over-predicted by 3-, 7- and 2-fold, respectively, by use of allometry. Of the species tested, the cynomolgus monkey seemed to be the most useful for predicting kinetics in man when the approach based on concentration-time transformations was used. Thus, for half-life (t(1/2)), CL and Vd(ss), the observed mean values of 1.7 h, 459 mL min(-1) and 24 L kg(-1) in man were very close to the values predicted from the cynomolgus monkey (1.7 h, 652 mL min(-1) and 22 L kg(-1), respectively). The results show that there are large inter-species differences for kidney and liver excretion of napsagatran. This is probably because of the involvement of active transport processes, which compromised the kinetic extrapolation from animal to man, although a more thorough investigation of the transporters involved in the disposition of napsagatran is necessary to enable better understanding of the species differences observed. 相似文献