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21.
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25 of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression. Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis (68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results.  相似文献   
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BACKGROUND: To clarify the roles of rat sarcoma (Ras)/mitogen-activated protein kinase (MAPK) signaling pathway in oncogenesis and cytodifferentiation of odontogenic tumors, K-Ras gene status and expression of Ras, Raf1, MAPK/extracellular signal-regulated kinase (ERK) kinase (MEK)1, and ERK1/2 proteins were analyzed in ameloblastomas as well as in tooth germs. METHODS: Paraffin sections of 10 tooth germs and 46 benign and 6 malignant ameloblastomas were examined immunohistochemically for the expression of K-Ras, Raf1, MEK1, and ERK1/2. Frozen tissue samples of 22 benign ameloblastomas and 1 malignant (metastasizing) ameloblastoma were analyzed by direct DNA sequencing to detect K-Ras gene alteration. RESULTS: Immunohistochemical reactivity for K-Ras, Raf1, MEK1, and ERK1/2 was detected in both normal and neoplastic odontogenic epithelium, and these molecules were reactive chiefly with odontogenic epithelial cells neighboring the basement membrane. Plexiform ameloblastomas showed slightly stronger expression of these Ras/MAPK signaling molecules than follicular ameloblastomas. Keratinizing cells and granular cells showed decreased reactivity for the signaling molecules. Basal cell ameloblastomas showed slightly stronger reactivity for the signaling molecules than did the other subtypes. K-Ras immunoreactivity in malignant ameloblastomas was lower than that in dental lamina of tooth germs. Direct DNA sequencing showed a GGT to GCT point mutation at codon 12 of K-Ras gene in one ameloblastoma. Conclusion: Expression of K-Ras, Raf1, MEK1, and ERK1/2 in tooth germs and ameloblastomas suggests that Ras/MAPK signaling pathway functions to regulate cell proliferation and differentiation in both normal and neoplastic odontogenic epithelium. K-Ras gene status implied that K-Ras mutations might play a minor role in oncogenesis of odontogenic epithelium.  相似文献   
24.
Summary A case of a solid parotid tumour in a 16-year-old boy is presented. Histologically, the tumour demonstrated some peculiar findings. An acinar pattern was predominant although every component seen in the normal salivary gland was present, namely, serous and mucous gland acini, ducts, myoepithelial cells, adipose and lymphoid tissue. Large eosinophilic granules were abundant in the large acinar cell cytoplasm. Immunohistochemically, the tumour demonstrated the proteins which are present in the normal parotid gland, for example, amylase, lactoferrin and lysozyme. Electron microscopic features were quite similar to those of normal parotid tissue except for accumulation of a large number of cytoplasmic granules in the acinar cells. There has been no previous report of a tumour with the same features as seen in this case. Our pathological diagnosis is hamartoma, although the possibility of hyperplasia or neoplasia can not be excluded.  相似文献   
25.
Objective: The standard operation for patients with stage IA lung adenocarcinoma is considered to be a lobectomy. Recently, some researchers have reported that patients with tumors showing greater proportions of ground-glass opacity (GGO) at computed tomography (CT) could be candidates for limited resection, because of its less aggressive nature. However, the lack of a precise definition or standard measuring method of GGO prevents its general use as an index for planning limited resection. Therefore, we attempted to define GGO based on CT number and measured it more objectively. Methods: Between 1998 and 2001, 90 patients with clinical stage IA adenocarcinoma, who underwent standard or intentional limited resection and whose images of chest high-resolution CT were preserved in Digital Imaging and Communications in Medicine (DICOM) format, constituted the study population. The tumor shadow seen on the solid window (WL, −160 HU; WW, 2 HU) was regarded as the central solid area of the tumor seen on the lung window, and GGO was defined as the whole tumor area with the exception of the central solid area. Each area was measured using Scion Image (Scion Corp., Frederick, MD). We analyzed the relationship between the proportion of GGO and both of pathologic findings and recurrence. Results: Among the 90 tumors, 31 (34.4%) were calculated to have a GGO area greater than or equal to 50%. Of these, 27 (87%) tumors were bronchioloalveolar carcinoma. Lymphatic and vascular invasions, or nodal involvement were found only in patients with a smaller proportion of GGO (<50%) (P<0.05). During the follow-up period (median 36 months), recurrences occurred in eight patients who were diagnosed as having tumors showing smaller proportion of GGO (<50%). Conclusions: Tumors with a greater proportion of GGO measured by our method are thought to have a less invasive nature. Our objective measuring method of GGO could be useful for future multicenter trials to elucidate the value of limited resection for clinical stage IA adenocarcinoma based on the proportion of GGO.  相似文献   
26.
We report a case of corticobasal degeneration (CBD) presenting with visual hallucination. A 65-year-old woman showed clumsiness of the left hand. Clinical symptoms slowly progressed to include rigidity, which was left side dominant, limb-kinetic apraxia of the left hand, disorder of construction and dressing, unilateral spatial neglect, cortical sensory loss and alien limb phenomenon. Cranial MRI showed atrophy of the parietal and medial aspect of the frontal lobes, which was more severe on the right than on the left. SPECT images showed hypoperfusion in the parietal, frontal and temporal lobes, which were similarly more severe on the right than on the left. We diagnosed the patient as having CBD based on the clinical symptoms. Two years' later, she developed recurrent visual hallucinations that were typically well formed and detailed. Since patients with CBD generally do not experience visual hallucination, this case is considered the very rare and indicates the possibility that visual hallucination may be one of the clinical symptoms of CBD.  相似文献   
27.
This report describes our experience with a 60 year old male who suffered from a recrudescence of groove pancreatitis. He had been treated by conservative medication therapy by proton pump inhibitor used for therapy of duodenal ulcer, and was in remission. During a follow-up one year later, endoscopy revealed gastric cancer, for which a proximal gastrectomy and vagotomy were performed. The patient continues to remain in remission for the groove pancreatitis. Our experience with the clinical course of this disease, in which treatment for duodenal ulcer was used effectively, offers new insights into the progression and therapy of groove pancreatitis.  相似文献   
28.
Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets would show any modification of parathyroid hormone (PTH) and calcitonin (CTN). The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were measured by competitive protein binding assays before and after each program. The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that (256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma 1,25-(OH)2-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase in the 1,25-(OH)2-vitamin D levels, whereas their CTN levels were unchanged. These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as for a low serum level of CTN in patients with NIDDM.  相似文献   
29.
We report here an unusual case of fibrous histiocytoma in which an area of xanthogranuloma was observed histologically. Our case suggests that adult xanthogranuloma is a variant of fibrous histiocytoma.  相似文献   
30.
Summary: Severe secondary hyperparathyroidism in chronic dialysis patients has been recently treated by supraphysiological concentration of calcitriol achieved through pulse therapy. However, there are many patients resistant to this therapy, who usually have larger parathyroid gland(s). to overcome this resistance, calcitriol was injected directly into the enlarged glands under ultrasonographic guidance. We injected 70–90% of the calculated gland volume of calcitriol solution (1 μg/mL) into the glands of 7 patients three times per week for 2 weeks. the parathyroid hormone (PTH) levels decreased significantly after 2 weeks of direct injections of calcitriol. Following a further 4 weeks of calcitriol pulse therapy, PTH levels remained suppressed and serum alkaline phosphatase activity and the volume of parathyroid glands also decreased. During the long-term follow up, five patients remained well controlled with calcitriol pulse therapy, while two patients needed ethanol injections to control hyperparathyroidism. Although we could not completely rule out a toxic effect of the vehicle, direct injection of calcitriol into parathyroid glands may be another treatment option for chronic dialysis patients. Our data further support the important role of resistance of parathyroid cells to calcitriol in the pathogenesis of parathyroid hyper function in uraemic patients.  相似文献   
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