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11.
12.
Combined large cell neuroendocrine carcinoma 总被引:1,自引:0,他引:1
Toshiya Bessho Keiya Yokochi Teruhisa Sakurai 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(9):426-428
We report a case of combined large cell neuroendocrine carcinoma. A 78-year-old man with vertigo was referred to our hospital
where chest X-ray revealed a tumor shadow in the right lung. A transbronchial lung biopsy specimen verified a diagnosis of
non-small cell lung carcinoma (cT1N0M0). Right lower lobectomy with mediastinal lymph node dissection (#7,8,9) was performed.
A postoperative histological diagnosis was combined large cell neuroendocrine carcinoma of a component of squamous cell carcinoma
[pT4 (pm) N2M0]. The patient received concurrent chemoradiotherapy due to upper mediastinal lymph node metastasis 4 months
after surgery. The chemoradiotherapy well responded and the patient remains well 9 months after surgery. 相似文献
13.
14.
TAKASHI TAKEUCHI HIROSHI KITAGAWA TOMOHIRO IMAGAWA MASATO UEHARA 《Journal of anatomy》1998,193(2):233-239
The proliferation sites and cellular kinetics of villous epithelial cells and M cells in the intestine of the adult chicken have never been clarified. In this study, we determined the proliferation sites in the chicken caecum using colchicine treatment and detection of proliferative cell nuclear antigen (PCNA). The cellular kinetics of these cells were also studied using bromodeoxyuridine (BrdU) as a tracer. Enterocytes in their mitotic period were observed along the entire length of the intestinal crypt of the caecum, with a denser distribution in the middle portion of the crypt, except for the caecal tonsil. The centres of distributions were at 49% of the distance from the bottom of the crypt in the base and 41% in the apex of the caecum. In the caecal tonsil, the centres of distributions were at 64% in the long type of crypt from the bottom of the crypt and at 44% in the short type of crypt. On the other hand, the PCNA-positive enterocytes were distributed more densely at the bottom of the crypt, except for the caecal tonsil. The centres of distributions were at 36% in the base from the bottom of the crypt, 37% in the body, and 34% in the apex. In the caecal tonsil, they were at 54% in the long type of crypt and 44% in the short type. The BrdU-labelled enterocytes reached to the basement of the intestinal villi in all caecal portions at 1 d after the BrdU administration. The leading edge of the labelled enterocytes disappeared from the villous tips at 4 d in the base and the body and 3 d in the apex. In the caecal tonsil, the BrdU-labelled microvillous epithelial cells and the M cells appeared near the orifice of the crypt at 1 d, and BrdU-labelled M cells were not observed in the crypt. Thereafter, almost all of these cells disappeared at 5 d from the follicle associated epithelium (FAE). These results suggest that M cells are transformed from their precursors within 1 d, and the turnover time for M cells occurs within 4 d after the cell division of the precursors. 相似文献
15.
A monoclonal antibody (RH1-38) which blocks multiple systems of cell-mediated cytotoxicity was functionally characterized. RH1-38 specifically blocks, in the absence of complement, natural killer (NK) activity (K562 targets) without any effect on NK-K562 conjugate formation. Kinetic studies suggested that the antibody blocks a step that occurs 30-120 min after effector populations are mixed with target cells. Single-cell cytotoxicity assays in agarose, combined with standard 51Cr release assays and Michaelis-Menten analysis revealed that RH1-38 markedly decreases Vmax and the number of active NK cells, again without any effect on the number of target-binding cells. The maximum recycling capacity was usually decreased, but in some experiments unchanged, in the presence of the monoclonal antibody. RH1-38 inhibited equally well whole peripheral blood mononuclear leukocytes (PBML), Percoll-fractionated lymphocytes enriched for NK activity, and interferon (IFN)-boosted NK activity. PBML exposed to RH1-38 and then washed mediated depressed NK activity which was partially reversed by subsequent treatment with IFN. These studies are most consistent with the hypothesis that RH1-38 inhibits a step late in the NK cytolytic mechanism rather than through an effect on conjugate formation. The primary effect is probably not on the IFN-generating or boosting mechanism, but a secondary effect on IFN-related mechanisms cannot be ruled out. Inhibition through an effect on a small lymphocyte modulator of NK activity is also unlikely but not rigorously excluded. Thus, RH1-38 appears to inhibit NK activity through a direct effect on NK effector cells, probably by interfering with a cell-surface molecule which is important in the expression of NK activity. The companion paper demonstrates that this monoclonal antibody immunoprecipitates a molecule which is very similar or identical to the LFA-1 antigen. Thus, RH1-38 recognizes either a novel epitope on the LFA-1 molecule or alternatively a distinct, functional killer cell surface molecule. The epitope appears to be involved in a late step in the cytolytic mechanism, possibly part of the effector cell lytic machinery. 相似文献
16.
Increase in the proportion of granulated CD56+ T cells in patients with malignancy. 总被引:6,自引:1,他引:6 下载免费PDF全文
Y Takii S Hashimoto T Iiai H Watanabe K Hatakeyama T Abo 《Clinical and experimental immunology》1994,97(3):522-527
Evidence is presented for the existence of a unique T cell population which expressed one of the natural killer (NK) markers, CD56 antigen, in humans. Although such CD56+ T cells were a minor population in the peripheral blood (< 10%), they were abundant in the liver (up to 50%), which was recently demonstrated to be a major organ for extrathymic T cell differentiation in mice. As in the case of extrathymic T cells in mice, these CD56+ T cells in humans contained a higher proportion of gamma delta T cells than did CD56- T cells, contained double-negative CD4-8- cells, and had the morphology of large granular lymphocytes. This unique population of CD56+ T cells tended to be elevated in the blood and among tumour-infiltrating lymphocytes in patients with colorectal cancer, especially in advanced cases. These results raise the possibility that, as in mice, CD56+ T cells with extrathymic T cell properties may also be associated with tumour immunity in humans. 相似文献
17.
Primary cutaneous B-cell lymphoma in Japanese patients 总被引:1,自引:0,他引:1
Primary cutaneous B-cell lymphoma (PCBCL) is a rare group of lymphoproliferative disorders. There have been few reports of Japanese patients with PCBCL, so the present study investigated the clinicopathological and immunological features and Bcl-2 gene rearrangement and protein expression in 28 Japanese patients with PCBCL. According to the Revised European-American Lymphoma (REAL) classification, there were 25 diffuse large B-cell lymphomas (DLBCL), one Burkitt type lymphoma, one lymphoblastic lymphoma and one marginal zone cell lymphoma. Of the 25 DLBCL, 17 were in males and eight in females, with an average age of 69.4 years. Follow-up data were available in 19 cases of DLBCL of which seven died and 12 were alive. The overall 5-year survival rate was 61%. Cases of DLBCL involving the legs were found to have poorer clinical outcomes; two of four cases with leg lesions died, with a mean survival of 13 months. Of 14 cases with non-leg lesions, four died, and the mean survival was 38.9 months. Only one case of Burkitt type lymphoma was CD10 positive. Bcl-2 rearrangement was not observed in 13 cases studied by polymerase chain reaction. Bcl-2 expression was observed in nine of 13 cases studied. All five cases with leg lesions exhibited Bcl-2 expression, but four of six cases with non-leg lesions also expressed the protein. These results show that DLBCL is the most frequent subtype of PCBCL in Japanese patients and that the prognosis of Japanese patients with DLBCL is worse than that of reported European cases. The study also found that PCBCL was frequently associated with Bcl-2 expression, which was not site-confined, and that there was no evidence for a follicular center origin of PCBCL. 相似文献
18.
Ijiri R Tanaka Y Kato K Misugi K Ohama Y Shinkai M Nishi T Aida N Kondo F 《Pathology international》2001,51(1):16-19
With the application of liver transplantation for patients with biliary atresia (BA), we have had the opportunity to review the clinicopathologic features of the native livers from 10 transplanted BA patients. A single large nodule at porta hepatis (hilar nodule) was noted in three of 10 patients, and an ill-defined nodule-like lesion at porta hepatis was present in two other patients. The three BA patients with hilar nodules were long-term survivors, compared to the patients with nodule-like and those without nodules. The hilar nodules measured between 5.0 cm and 8.0 cm and histologically, they were partly surrounded by fibrous septa with relatively well-preserved liver architectures and fewer inflammatory cells at the portal triads when compared to the surrounding cirrhotic lesions. No nuclear or cellular atypia was observed. Proliferating cell nuclear antigen labeling index was higher in the surrounding cirrhotic lesions than the hilar nodules. The nodule-like lesions at porta hepatis also showed similar light microscopic and immunohistochemical features as the hilar nodules. These hilar nodules did not seem to contain any malignant potential. The benign histology with relatively well-preserved liver architecture and the preferential site of occurrence at porta hepatis where bile seemed to flow more smoothly, suggested possible residues of less-affected hepatic tissues. 相似文献
19.
Cell proliferation may be evaluated by various methods, including Ki-67 immunohistochemistry and measures of telomerase activity. Both methods would theoretically show comparable increases in a given case. To evaluate the relationship between these 2 markers of proliferation in aggressive mature B-cell lymphomas, 48 cases were studied. The study group included 5 cases of mantle cell lymphoma (MCL); 6 cases of Burkitt's/Burkitt's-like lymphoma (BL); 9 cases of follicular lymphoma, grade 3 (FLC); and 28 cases of diffuse large B-cell lymphoma (DLC). Telomerase activity was measured as total product generated (TPG) units, and TPG results for the aforementioned cases were compared to the TPG results for 10 cases of reactive follicular hyperplasia. An overlap in TPG scores between reactive cases and lymphoma cases was found. Significant differences in both log TPG (P = 0.0443) and Ki-67 (P = 0.0006) were seen in the different lymphoma types. A positive correlation between Ki-67 percentage and TPG score was identified in FLC (r = 0.9281; P = 0.0003), but a poor correlation between these 2 indicators was seen in the other lymphoma types. Cluster analysis identified distinct patterns for MCL, FLC, and BL, but heterogeneous patterns for DLC. Because increases in both Ki-67 proliferation and telomerase activity are reported in normal germinal centers (GCs), these tests were also evaluated for usefulness as markers of a GC cell phenotype. Among the FLC and DLC cases, features of a GC phenotype significantly correlated with increased Ki-67 percentage (P = 0.0152), but not with increased log TPG. An elevated log TPG correlated with CD10 expression, and elevated Ki-67 percentage correlated with both CD10 and BCL-6 expression. TPG level and Ki-67 percentage did not correlate with the presence of t(14;18) or BCL-2 protein expression. Although the proliferation patterns were fairly distinctive for MCL, FLC, and BL, these studies show that markers of cell proliferation do not by themselves,identify distinct subtypes of large cell lymphomas. With the exception of FLC, the tumors exhibited poor correlation between telomerase activity and Ki-67 proliferation index. These tests did show some correlation with expression of GC cell phenotypic markers, however. 相似文献
20.
BACKGROUND: Tumor segment resection is one of the standard methods for the treatment of bone tumors. However, the reconstruction of bone defects atumor resection faces many challenges. A growing number of researchers are focusing on 3D-printed prostheses for bone defect repair and reconstruction following bone tumor surgery. OBJECTIVE: To explore the feasibility of 3D-printed prostheses in the reconstruction of large bone defect following bone tumor surgery and to evaluate the postoperative outcomes. METHODS: Retrospective analysis of clinical data of 24 patients [19 males and 5 females, age 23.8 (6-61) years] who underwent bone tumor resection and 3D-printed prosthesis implantation in the Department of Bone Oncology, the First Affiliated Hospital of Xinjiang Medical University from December 2020 to September 2021 was conducted. There were 7 cases with distal femur tumor, 5 with pelvis tumor, 4 with proximal tibia tumor, 3 with middle femur tumor, 1 with distal tibia tumor, 1 with proximal humerus tumor, 1 with middle humerus tumor, 1 with scapula tumor, 1 with ulna tumor, and 22 cases with primary tumors (13 osteosarcoma, 4 Ewing sarcoma, 2 giant cell tumor of bone, 1 chondroblastoma, 1 chondrosarcoma, and 1 osteoblastoma), 2 metastatic carcinoma. Preoperative and postoperative imaging data were recorded and neoadjuvant chemotherapy was administered in 17 cases before surgery. The Musculoskeletal Tumour Society score was used to assess limb function before surgery and 6 months after surgery, and pain was assessed by the Visual Analog Scale, as well as the complications were recorded. RESULTS AND CONCLUSION: (1) All patients undergoing resection of the tumor segment and 3D-printed prosthesis implantation for the reconstruction of the bone defect were followed for 6-49 months, and the results showed that the length of osteotomy was (18.2 ± 7.3) cm and an average intraoperative bleeding volume was 740 (100-3 000) mL. (2) Two patients died of systemic metastasis, the remaining 22 had no pulmonary metastasis or recurrence during the follow-up period, and 1 patient developed aseptic loosening of the prosthesis at 25 months postoperatively. (3) The Musculoskeletal Tumour Society scores were significantly increased, while Visual Analog Scale scores were significantly decreased (P < 0.05) at 6 months postoperatively. (4) The Musculoskeletal Tumor Society score was rated excellent in all 22 patients at the final follow-up. (5) These results suggest that 3D-printed prosthesis is suitable for the reconstruction of large bone defects caused by bone tumor resection. Patients have good postoperative function and few complications. However, further investigations are needed to explore long-term follow-up results. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved. 相似文献