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1.
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.  相似文献   
2.
BACKGROUND: The objective of this study was to evaluate the efficacy and safety of first-line high-dose chemotherapy (HDCT) combined with peripheral blood stem cell transplantation (PBSCT) for patients with advanced extragonadal germ cell tumors (EGGCT). METHODS: Six male patients with advanced non-seminomatous EGGCT were treated with HDCT combined with PBSCT following 2-3 cycles of conventional-dose induction chemotherapy. The regimens used for HDCT were carboplatin, etoposide and ifosfamide (ICE) in five patients and ICE plus paclitaxel (T-ICE) in one patient, and that for induction therapy was cisplatin, etoposide and bleomycin (PEB) in all patients. As a rule, HDCT was continuously administered until alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin normalized (beta-HCG). RESULTS: Following 1-6 courses of HDCT (median, 4 courses), beta-HCG and AFP were normalized in all patients, and five and one patient were diagnosed as showing partial remission and stable disease, respectively. Five patients underwent surgical resection of residual tumors after HDCT, yielding necrotic tissue in two, mature teratoma in two, and viable cancer tissue in one, and the surgical margin was negative in all patients. At a median follow-up of 36 months, five patients were alive and disease-free, whereas the remaining one died of disease progression. Although all patients had grade 3 hematological toxicity, there was no treatment-related death by combining PBSCT. CONCLUSIONS: First-line HDCT with PBSCT could be safely administered to patients with advanced EGGCT, and the antitumor effect of this treatment was comparatively favorable. First-line HDCT therefore may represent an attractive option for patients with advanced EGGCT.  相似文献   
3.
The centrifugal pump (bio-pump) as a temporary shunt during the operation of the descending thoracic aortic aneurysms was used as effective means of providing adequate circulation to the lower body. But in the acute excessive bleeding, estimates of the flow to the abdominal viscera as well as spinal cord are variable. We employed bio-pump with an interposed soft reservoir under low dose systemic heparinization in 2 cases of the descending thoracic aortic aneurysms. Both cases had been maintained adequate flow and perfusion pressure in the time of acute excessive hemorrhage, and there were no evidence of the organ failures due to microembolism. Furthermore, postoperative hemorrhage by using low dose heparin seemed to be unrisky. Compared with the previous method, bio-pump with an interposed soft reservoir provides adequate circulation to the lower body even if acute excessive bleeding occurred.  相似文献   
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Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases. Received: 4 October 1996 / Accepted: 6 December 1996  相似文献   
6.
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor. This study was carried out as a group project. The authors' institutions are as follows  相似文献   
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To determine the healing potential and healing process of torn supraspinatus tendons, in situ hybridization was used to localize cells containing α1 type-I procollagen mRNA. Biopsy specimens of torn supraspinatus tendons from 19 patients with complete-thickness tears and 13 patients with incomplete-thickness tears were obtained during surgery. Four macroscopically normal supraspinatus tendons were obtained to serve as normal controls. Specimens were fixed in 10% buffered formalin and embedded in paraffin. A 22-mer oligonucleotide probe was labeled with digoxigenin and used as an in situ marker. The labeled cells were mainly composed of tenocytes and undifferentiated mesenchymal cells. In complete-thickness tears, the labeled cells at the proximal tendon stumps in the specimens that were obtained less than 4 months after trauma were significantly more abundant than in the specimens obtained 4 months or more after trauma. However, the number of labeled cells was maintained at the torn portion even in long-standing incomplete-thickness tears. The labeled cells at the margins of concomitant intratendinous extensions of the tears were detected even in the long-standing tears. The intratendinous extensions exhibited more labeled cell than were bursal-side or joint-side layers of the tendon substance in the incomplete-thickness tears (p < 0.05). The torn supraspinatus tendon may possess an intrinsic healing capability in the intermediate and late phases of tendon healing. Incomplete-thickness tears and concomitant intratendinous extensions can continue to rupture after the initial injury.  相似文献   
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10.
We investigated the effects of mild and non-lethal ischemic insult on neuronal death following subsequent lethal ischemic stress in various brain regions, using a gerbil model of bilateral cerebral ischemia. Single 10-min ischemia consistently caused neuronal damage in the hippocampal CA1, CA2, CA3 and CA4, layer III/IV of the cerebral cortex, dorsolateral part of the caudoputamen and ventrolateral part of the thalamus. On the other hand, in double ischemia groups, 2-min ischemic insult 2 days before 10-min ischemia exhibited significant protection in the CA1 and CA3 of the hippocampus, the cerebral cortex, the caudoputamen and the thalamus. Five-min ischemic insult 2 days before 10-min ischemia also showed protective effect in the same areas as those of 2-min ischemia except for the CA1 region of the hippocampus, while 1-min ischemic insult exhibited no protective effect in any brain regions. In the immunoblot analysis, both 2- and 5-min ischemia caused increased synthesis of heat shock protein 72 (HSP 72) in the hippocampus, but 1-min ischemia did not. The present study demonstrated that the ‘ischemic tolerance’ phenomenon was widely found in the brain and also suggested that ischemic treatment severe enough to cause HSP 72 synthesis might be needed for induction of ‘ischemic tolerance’.  相似文献   
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