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31.
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide (MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment of liver failure.  相似文献   
32.
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy.  相似文献   
33.
34.
The effect of XKJ-001, a crude drug preparation based on Seisho-ekki-to, was investigated on the hematocrit, plasma volume, extracellular and interstitial fluid volumes as well as water excretion in mice. Mice were housed in an animal room maintained at 34 degrees C for 3 d with water and food freely available. While the hematocrit, extracellular and interstitial fluid volumes increased, the plasma volume decreased. These results suggest that the distribution of body water in mice housed at high environmental temperature exhibit the state of water metabolism disorders (Suitai) described in Kampo medicine. After the administration of XKJ-001 (3 g/kg, once a day) for 5 d, mice were housed in an animal room maintained at 34 degrees C for 3 d. The administration of XKJ-001 was allowed to continue on the day 0, day 1 and day 2. XKJ-001 inhibited the increase in hematocrit and the changes in body water distribution of mice induced by high environmental temperature. An effect of XKJ-001 on water excretion in mice was investigated in comparison with hydrochlorothiazide (HTZ). Distilled water (D.W., 100 ml/kg) or bicarbonate saline (B.S., 100 ml/kg) was intraperitoneally injected immediately after the oral administration of XKJ-001 (1.5 g/kg) or HTZ (15 mg/kg). The water excretion was enhanced after 3 h for XKJ-001 and after 6 h for HTZ after the intraperitoneal injection of D.W. As for the intraperitoneal injection of BS, HTZ enhanced the water excretion, however, XKJ-001 exhibited no effect. These results suggest that XKJ-001 has activities on water maldistribution and facilitates the water excretion.  相似文献   
35.
Effects of hepatoportal osmo-receptive (or sodium-receptive) afferents on neurons within the dorsal motor nucleus of the vagus (DMV) were investigated electrophysiologically in urethane-chloralose anesthetized rats. Responses of 56 spontaneously active neurons to antidromic stimulation of the ventral trunk of the subdiaphragmatic vagus were recorded in the left DMV. Among them, 35 neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve (inhibitory neurons), except two neurons that were slightly excited. Effects of portal infusion of 3.6% NaCl were examined on 26 inhibitory neurons. Sixteen neurons increased their discharge rates and one neuron decreased its discharge rate in response to portal infusion of hypertonic saline. Thirty-five DMV neurons responded to electrical stimulation of the dorsal trunk of the subdiaphragmatic vagus were inhibited by electrical stimulation of the hepatic branch of the vagus. Four neurons were excited by this stimulation. Relatively smaller number of neurons (5 out of 22 inhibitory neurons) increased their discharge rates in response to portal infusion of hypertonic saline. In conclusion, the response of DMV neuron observed in this experiment was characterized by increasing the frequency of spike discharges in response to portal infusion of hypertonic saline. However, these neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve. These results suggest that the hepatoportal osmoreceptive afferents may be conveyed to the DMV via inhibitory synapses.  相似文献   
36.
Two flat adenomas and a flat mucosal carcinoma of the colon were reported in patients with synchronous and metachronous colonic carcinomas. These lesions were almost flat and were not detected by preoperative endoscopic examinations. Colonoscopists should be aware of the presence of flat adenomas, which can be easily missed, and recognize them as lesions that play an important role in the "adenoma-carcinoma sequence."  相似文献   
37.
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen.  相似文献   
38.
Effects of dietary iodine on chemical induction of thyroid carcinoma   总被引:1,自引:0,他引:1  
Effects of dietary iodine on the induction of thyroid carcinoma using N-nitrosobis(2-hydroxypropyl)amine (BHP) were studied. Male Wistar rats were fed with an iodine-adequate diet (IAD group), an iodine-rich diet (IRD group) and an iodine-deficient diet (IDD group), respectively, until the time of sacrifice. From the 2nd experimental month, animals were injected with BHP once a week for 10 weeks. In the IAD and IRD groups, benign nodules and papillary carcinoma were found. The incidence of rats with benign nodules was 100% in both groups and animals with papillary carcinoma in the IAD and IRD groups comprised 33% and 29%, respectively. The area of the thyroid gland occupied by nodular lesions was much narrower in the IRD group than in the IAD group. In the IDD group, the thyroid showed marked enlargement due to multiple nodular proliferation of follicle cells. The incidence of rats with carcinoma was 100%, and not only papillary but also follicular carcinoma and one pulmonary metastasis were found. As the iodine content of the diet decreased, the nodular lesions increased in width and number, and the incidence of carcinoma in rats became higher. These effects of dietary iodine are probably related to the goitrogenic and/or promoting effects of TSH.  相似文献   
39.
The nature of signals that govern the development of immunoglobulin heavy chain-dependent B cells is largely unknown. Using mice deficient for the B cell-expressed Src-family protein tyrosine kinases (SFKs) Blk, Fyn and Lyn, we show an essential role of these kinases in pre-B cell receptor (pre-BCR)- mediated NF-kappaB activation and B cell development. This signaling defect is SFK specific, as a deficiency in Syk, which controls pre-B cell development, does not affect NF-kappaB induction. Impaired NF-kappaB induction was overcome by the activation of protein kinase C (PKC)-lambda, thus suggesting the involvement of PKC-lambda in pre-BCR-mediated SFK-dependent activation of NF-kappaB. Our data show the existence of a functionally distinct SFK signaling module responsible for pre-BCR-mediated NF-kappaB activation and B cell development.  相似文献   
40.
The histogenesis of malignant fibrous hlstlocytoma (MFH) was studled using clsplatln (CDDP)-resistant MT-R8 and MT-R9 cells derlved from cloned undlfferentiated MT-8 and flbrohlstlocytic MT-9 cells, resoecthfely, which had been established from transplantable rat MFH. CDDP concentrations requlred for 50% suppression of prollferation of MT-R8 and MT-R9 cells were 5.4– and 3.3-fold greater than those of parental MT-8 and MT-9, respectively. MT-R8 and MT-Rg showed the higher positive rates to histimytic lysosomal/ antigenic (ED1 and ED2) markers. The number of a-smoath muscle actin (SMA)-positive cells significantly Increased in MT-RB; SMA-positlve cells were also obsenred in MT-R9, but no difference was seen between MT-9 and MT-R9. MT-R8 and MT-R9 expressed both histiwytic and myofibroblastic phenotypes. However, the histology of subcutaneous tumors induced in syngeneic rats by MT-R8 and MR-R9 did not always reflect their in vitro nature. MT-R8 developed undiffer-entlated sarcomas similar to parental MT-8 tumors. In contrast, MT-R9 induced tumors with polytypic histologies such as the storiform growth pattern, neoplastlc growth of granular cells and myofibroblasts, osteosarcoma-like areas, collagen-rich areas containing well-developed fibroblasts and areas involvlng many lipoblasts. These In vivo observatfons suggest the multidlrectional differentiation of MT-R9 cells. Phenotypic modulation of rat MFH cells seemed to be easily induced by CDDP. A possible histogenesis of MFH was discussed based on the data collected.  相似文献   
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