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Wide attention has been given to hyperthermia as a new measure for cancer treatment. Clinical trials of hyperthermia, as they possess antitumour activity on some occasions. When cells were incubated with oleic we examine if fatty acids exert a synergistic effect on Ehrlich ascites tumour cells when combined with hyperthermia, as they possess antitumour activity on some occasions. When cells were incubated with oleic acid and linoleic acid (unsaturated fatty acids) at 37 degrees C, the DNA synthesis of cells was significantly inhibited. Palmitic and stearic acids, which are saturated fatty acids, did not suppress DNA synthesis. Hyperthermic treatment without the presence of fatty acids at 42 degrees C for 1 h decreased DNA synthesis to 62% of the control level of 37 degrees C. The combination of an unsaturated fatty acid and hyperthermia synergistically suppressed DNA synthesis. When the cells were incubated in serum-free medium containing 0.1% albumin, unsaturated fatty acids were more effective in inhibiting DNA synthesis. However, saturated fatty acids had little or no effect on DNA synthesis in control or hyperthermia-treated cells. These results indicate that unsaturated fatty acids are useful for enhancing the inhibitory effect of hyperthermia on DNA synthesis, which may increase the in vitro antitumour effects of hyperthermia.  相似文献   
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CY pretreatment augmented the generation of cytotoxicity in the draining lymph node cells in mice after subcutaneous immunization with allogeneic spleen cells, or in the non-adherent peritoneal exudate cells after intraperitoneal immunization with these cells. Marginal cytotoxicity in the spleen cells after this immunization was suppressed by CY pretreatment. Similar divergent effect of CY pretreatment on the generation of cytotoxic activity in the draining lymph nodes and the spleen was also observed after immunization with allogeneic tumour cells which can induce high degrees of cytotoxicity without CY pretreatment. These results indicate that cytotoxic T lymphocyte (CTL) generation at the site of direct graft rejection appears to have a nature different from that related to CTL generation in the spleen. A discussion is made as to the role of CTL in the peripheral site and the spleen in cases of in vivo allograft rejection.  相似文献   
34.
AIM/METHODS: Diabetic nodular glomerulosclerosis is considered to be the specific renal lesion of diabetes mellitus (DM). However, some cases, in which nodular glomerulosclerosis was found without any manifestation of DM, have also occasionally been reported. We clinicopathologically examined seven cases without a prior history of DM. They consisted of six men and one woman with a mean age of 57 years, and included three cases with family history of DM and six cases with hypertension. RESULTS: Mean body mass index was 26.2 +/- 5.9 (means +/- SD) kg/m(2) and haemoglobin A1c 5.3 +/- 1.1% or haemoglobin A1 7.0 +/- 0.6%. Mean plasma glucose levels were 5.3 +/- 0.7 mmol/L at fasting and 10.1 +/- 1.9 mmol/L at 2 h of 75 g OGTT (normal: 1 patient; impaired glucose tolerance: 4 patients; DM: 2 patients). None of them showed diabetic retinopathy in fundoscopic ophthalmoscopy. Mean serum creatinine was 268 +/- 215 micromol/L, urinary protein 5.2 +/- 4.0 g/day, and three patients had mild haematuria. Renal biopsy revealed typical nodular glomerulosclerosis, a negative deposition based on an immunofluorescence study, and neither any significant electron dense deposits nor fibrils on electron microscopy. CONCLUSION: These patients at presentation had no overt clinical manifestations of glucose intolerance. Diabetic nodular glomerulosclerosis can occur in patients without overt DM, suggesting the role of factors additional to prolonged hyperglycaemia in the pathogenesis of this disorder.  相似文献   
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The coronavirus disease 2019 (COVID-19) is known to cause gastrointestinal symptoms. Recent studies have revealed COVID-19-attributed acute pancreatitis (AP). However, clinical characteristics of COVID-19-attributed AP remain unclear. We performed a narrative review to elucidate relation between COVID-19 and AP using the PubMed database. Some basic and pathological reports revealed expression of angiotensin-converting enzyme 2 and transmembrane protease serine 2, key proteins that aid in the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the pancreas. The experimental and pathological evaluation suggested that SARS-CoV-2 infects human endocrine and exocrine pancreas cells, and thus, SARS-CoV-2 may have a direct involvement in pancreatic disorders. Additionally, systemic inflammation, especially in children, may cause AP. Levels of immune mediators associated with AP, including interleukin (IL)-1β, IL-10, interferon-γ, monocyte chemotactic protein 1, and tumor necrosis factor-α are higher in the plasma of patients with COVID-19, that suggests an indirect involvement of the pancreas. In real-world settings, some clinical features of AP complicate COVID-19, such as a high complication rate of pancreatic necrosis, severe AP, and high mortality. However, clinical features of COVID-19-attributed AP remain uncertain due to insufficient research on etiologies of AP. Therefore, high-quality clinical studies and case reports that specify methods for differential diagnoses of other etiologies of AP are needed.  相似文献   
37.
We evaluated the surgical results for carcinoma of the gallbladder. Between 1971 and 1995 we treated 258 patients, 74 of whom were treated with simple cholecystectomy, 71 with extended cholecystectomy, and 24 with more extended operations. The tumors were classified according to the stage proposed by the Japanese Society of Biliary Surgery. For m and pm carcinoma simple cholecystectomy may have an excellent result. However, it is difficult to know cancer depth exactly before or during operation, especially when combined with inflammation due to gallstones. In Stage I disease, extended cholecystectomy had an excellent result. So extended cholecystectomy is needed even in the early stage of the disease. Second operation is needed in inapparent carcinoma of the gallbladder if the tumor is more than pm or the margin is positive. More extended operations may be needed in advanced stages for curative resection. Extended hepatic lobectomy combined with pancreaticoduodenectomy should be indicated only if the patients are in good condition because of its high postoperative mortality and morbidity without a significant improvement in survival.  相似文献   
38.
Two cases of primary gastric T-cell lymphoma associated with human T lymphotropic virus type 1 (HTLV-1) are presented. Case 1 was a 54-year-old man who had multiple ulcerating tumors in the lower corpus and gastric antrum. Case 2, a 60-year-old man, showed a large ulcerating tumor in the upper corpus. Both patients were positive for serum anti-HTLV-1 antibody and for the monoclonal integration of HTLV-1 proviral DNA in the tumor cells by Southern blot analysis. The patients were thus diagnosed as having primary gastric T-cell lymphoma associated with HTLV-1 of stage II(1). Case 1 underwent total gastrectomy followed by chemotherapy, while Case 2 was treated by chemotherapy and radiotherapy. Both patients have been in complete remission for more than 4 years (96 months in Case 1 and 50 months in Case 2) after the treatments. Although primary gastric T-cell lymphomas associated with HTLV-1 is characterized by an extremely poor prognosis, the present cases suggest that in the early stage, long-term survival can possibly be achieved with appropriate treatments.  相似文献   
39.
Multifocal fatty infiltration of the liver: report of six cases   总被引:1,自引:0,他引:1  
Images of computed tomography (CT), ultrasonography (US), angiography and radionuclide imaging were analyzed in six cases of multifocal fatty infiltration of the liver. Histologic confirmation of fatty infiltration was obtained in one patient by percutaneous biopsy. In the remaining patients, presumptive confirmation of the diagnosis was based on the CT number in one patient and partial or complete resolution of the lesions on repeat CT scans or US in 4 patients. CT and US were performed in all six patients. CT scans demonstrated multiple round areas of low attenuation within both lobes of the liver in all cases. US studies showed hyperechoic foci in three cases and diffuse inhomogeneous hyperechogenicity in three cases. Hepatic arteriograms in five cases and liver scintigrams in four cases showed no evidence of space-occupying lesions. In all cases, the lesions completely or partially resolved in follow-up CT and US, and in four cases the lesions disappeared within two months, so follow-up examinations within about 2 months are necessary to differentiate these from liver neoplasms.  相似文献   
40.
Remarkably high accumulation of Tc-99m-MDP is seen in the skull on bone scintigraphy of patients with renal osteodystrophy (ROD), especially with secondary hyperparathyroidism. For the quantitative evaluation, the Factor Analysis (FA) was used for the early phase of bone scan. Tc-99m-MDP (14.8 MBq/body weight kg) was injected as a bolus through the medial antecubital vein. Dynamic acquisition of 40 x 30 sec frames were performed in a 64 x 64 matrix. For pre-processing, nine points smoothing was carried out, and then the region of interest was set on the frontal image of the head for the FA. The FA was performed with an 8 x 8 sampling corresponding to 64 dixels from 4,096 dixels. Bone factor was clearly extracted by the FA. Then, two original parameters were calculated. One is the bone radionuclide uptake counts (Bu) which is the product of the total radionuclide counts of skull and the contribution ratio, the other is the uptake ratio (Br) derived by the time activity curve (physiological component) of the FA. These parameters of ROD were significantly different compared to those of controls. The FA seems to be useful in quantitative evaluation of bone mineral dynamics.  相似文献   
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