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151.
Lack of rapid initiating, promoting or sequential syncarcinogenic effects of di(2-ethylhexyl)phthalate in rat liver carcinogenesis 总被引:2,自引:0,他引:2
The effect of prolonged dietary administration of the peroxisomeproliferating plasticizer di(2-ethylhexy1)phthalate (DEHP wasstudied on liver carcinogenesis initiated by N-2- fltuorenylmxhmide(FAA) and with that of the neoplasm-promoter phenobarbital (PB).Also, DEHP was studied as an initiator by giving it in placeof FAA before PB. Male rats were fed FAA for 7 weeks to inducebepatocellular altered foci, and were subsequently given nochemical, 12 000 p.p.m. DEHP or 500 p.p.m. PB for 24 weeks inthe diet. In the rats fed DEHP, substantial hepatomegaly andperoxisome proliferation were induced. No evidence of indudionof hepatacellular altered foci or hepatic neoplasms was foundeither when DEHP was given alone for 24 weeks or for 7 weeksfollowed by PB. Also, DEHP fed for 24 weeks had no promotingeffect on liver altered foci that were induced by FAA and producedlittle or no enhancement of the occurrence of FAA-induced liverneoplasms. In contrast, PB exerted a marked enhancing effecton foci and substantially increased the incidence and multiplicityof liver neoplasms. Thus, the findings demonstrate that DEHPdid not have either a rapid initiating activity, a significantsequential syncarcinogenic activity, or a promoting effect onliver carcinogenesis under conditions in which numerous agentswith such activities have been identified. 相似文献
152.
Tranilast is an oral antiallergic agent developed in Japan. This study investigated the effect of prolonged administration of Tranilast on the bronchial sensitivity of 18 asthmatic subjects. They were treated for either less than 3 months or more than 3 months continuously. Methacholine loading testing was used to assess bronchial reactivity, and the respiratory parameters were recorded on an Astograph. Patients treated for longer than 3 months showed a significant decrease in bronchial sensitivity (p less than 0.05). The anticholinergic and bronchodilatory properties of Tranilast were also investigated in 8 subjects. No significant anticholinergic or bronchodilatory effects were observed following a single oral dose of 100 mg of Tranilast. 相似文献
153.
The purpose of this study was to clarify the significance of immunohistological staining for PCNA/cyclin in human colorectal lesions. Our results: The PCNA-positive cells existed at the bottom of colonic tubuli in the normal and hyperplastic conditions. In the neoplastic lesions, however, the positive cells were existed at the relatively surface of the mucosa (chi 2: P less than 0.01) and distributed irregularly from the bottom to the top of carcinoma tissue. These results suggested that immunohistological staining for PCNA would specifically detect the cell proliferation and be beneficial for practical use and clinical application of the diagnosis of the colorectal lesions. 相似文献
154.
Neutrophil elastase inhibitor reduces hepatic metastases induced by ischaemia-reperfusion in rats. 总被引:2,自引:0,他引:2
Koji Doi Tetsuya Horiuchi Masaru Uchinami Takanori Tabo Narisato Kimura Jun Yokomachi Makoto Yoshida Kuniyoshi Tanaka 《Acta chirurgica》2002,168(8-9):507-510
OBJECTIVE: To investigate the possibility in rats that ONO-5046 Na, a new recombinant inhibitor of neutrophil elastase, can reduce hepatic metastases induced by ischaemia-reperfusion. DESIGN: Laboratory experimental study. SETTING: Research laboratory, Japan. SUBJECTS: Male Fischer rats. INTERVENTIONS: Rats underwent 60 min of 70% partial hepatic ischaemia, after which rat colon adenocarcinoma cells (RCN-H4) were injected into the spleen. The animals were divided into two test groups and a control group. One group was given ONO-5046 Na intravenously at 10 mg/kg/hour. A second group was given a saline solution for the same period, while the controls were not made ischaemic. MAIN OUTCOME MEASURES: Three weeks after inoculation, the number of tumour nodules on the liver surface was counted. The anti-cancer effect of ONO-5046 Na was measured by monotetrazolium assay. RESULTS: Hepatic ischaemia-reperfusion increased the number of liver metastases of RCN-H4 in both clamped and unclamped hepatic lobes. ONO-5046 Na significantly inhibited this in unclamped lobes, but had no anti-cancer effect. CONCLUSION: Neutrophil elastase may have an important role in increasing haematogenous liver metastases by ischaemia-reperfusion, particularly in unclamped lobes. 相似文献
155.
Michio Kimura Kayoko Kurosawa-Ohsawa Mikiko Takahashi Masayoshi Koyama Shigeaki Tanaka Tetsuro Matsuishi 《Thrombosis research》1992,67(6):687-696
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C. 相似文献
156.
MRI of the brain in diabetes mellitus 总被引:15,自引:0,他引:15
Y. Araki M. Nomura H. Tanaka H. Yamamoto T. Yamamoto I. Tsukaguchi H. Nakamura 《Neuroradiology》1994,36(2):101-103
We studied the MRI appearances of the brain in 159 patients with diabetes mellitus (DM) and 2566 agematched individuals without DM (controls). The images were reviewed for cerebral infarcts, hemorrhage, atrophy and subcortical arteriosclerotic encephalopathy. Cerebral atrophy was significantly more frequent in patients with DM than in controls (P>0.005) from the sixth to the eighth decade. The frequency of atrophy was 41.2% in the 6th decade, 60.0% in the 7th and 92.3% in the 8th decade in DM, and 19.8%, 38.9% and 56.8% respectively in controls. Unexpectedly, there was no statistically significant difference in the incidences of cerebrovascular diseases at any age. 相似文献
157.
BACKGROUND. Some specific chromosome abnormalities for the leukemias have been proven to be associated with the prognosis of acute nonlymphocytic leukemia (ANLL). However, most of these reports included patients treated with different protocols. Therefore, some bias has been involved in the evaluation of the prognostic factors in such reports. METHODS. The authors studied the morphologic, cytogenetic, and clinical features of 136 patients (86 males and 50 females) with de novo ANLL treated with the same protocol of intensive induction chemotherapy using multivariate analyses. RESULTS. Chromosome abnormalities were detected in 62.5% of the patients. The overall complete remission (CR) rate of disease was 85.5% in these patients. More than 90% of the patients with t(8;21) and pseudodiploid abnormalities achieved experienced CR. However, CR rates in the patients with abnormalities of chromosome 5 or 7 were 50%. With multivariate analyses by the type of karyotypic abnormality, CR duration and survival time of the patients with t(8;21) were longer than those of patients with normal karyotype and abnormalities of chromosome 5 or 7. Abnormalities of chromosome 5 or 7 and hyperdiploid were associated with poor prognosis. Older age and lower platelet counts also were factors contributing to shorter survival times. With the analysis with French-American-British (FAB) classification, only hypoplastic leukemia was a poor prognostic factor. CONCLUSIONS. These data suggest that cytogenetic analyses plays an important role in estimating the prognosis of patients treated with intensive induction chemotherapy. 相似文献
158.
Yuzo Kodaira Tetsuo Shibuya Koushi Matsumoto Kiichiro Uchiyama Toshihiro Tenjin Nobutaka Yamada Shigeo Tanaka 《Surgery today》1997,27(8):745-748
A 66-year-old man died of massive gastrointestinal hemorrhage caused by a fistula between the third portion of the duodenum
and the abdominal aorta. An autopsy revealed that duodenal tuberculosis had resulted in the development of a fistula into
the aorta with no pathological changes, and no active pulmonary tuberculosis was found. Duodenal tuberculosis and primary
aortoduodenal fistula (ADF) without an aneurysm are both extremely rare. Thus, we report herein a unique case of primary aortoduodenal
fistula without an abdominal aortic aneurysm, but associated with duodenal tuberculosis, and review the current literature. 相似文献
159.
To find out what causes differences in phosphorylation states in neurofilaments (NF), we selected two types of dendrite, one provided with very few NFs (Purkinje cell) and the other with relatively many (anterior horn cell). We examined these with four monoclonal antibodies selected by the Western blot analysis, two (NE14 and SMI31) recongnizing only phosphorylated, SMI32 recognizing only nonphosphorylated, and N52 recognizing phosphorylation-independent epitopes of NF-H. The immunoperoxidase labeling of dendrites, and also of perikarya, in both neurons was detectable with all four antibodies. After the tissue was treated with Triton X-100, the labeling was still detectable with SMI32 or N52, but undetectable with NE14 and SMI31. The brain homogenate Triton-extracted supernatant after centrifugation at 100,000g for 1 hr showed the staining of NE14, SMI31, and N52 but not that of SMI32. In Purkinje cell dendrite and perikaryon, NFs always appeared singly. In the immunogold labeling, they were labeled only with SMI32 or N52. Labeling by NE14 or SMI31 was distributed throughout the cytoplasm and hardly associated with NFs. In the anterior horn cell dendrite and perikaryon, NFs appeared both single and in bundles. They were predominantly labeled with SMI31 or N52 when they were single, and with NE14, SMI31, or N52 when they were bundled. Even in one NF, portions that appeared single were labeled mostly with SMI32 or N52, while the remainder, to which other NFs approached closely, were labeled mostly with NE14, SMI31, or N52. Thus, when NFs appear singly, NF-H in their projections or cross-bridges with other organelles is not phosphorylated, while when NFs are bundled, NF-H is phosphorylated in crossbridges between NF core filaments. These data may explain why the NF-H is heavily phosphorylated in axons, where NFs are abundant, and not in dendrites and perikarya, where NFs are sparse. Wiley-Liss, Inc. 相似文献
160.
H J Jeon T Akagi Y Hoshida K Hayashi T Yoshino T Tanaka J Ito T Kamei K Kawabata 《Cancer》1992,70(10):2451-2459
BACKGROUND. The breast is rarely a primary site for extranodal malignant lymphoma. Most reported primary non-Hodgkin malignant lymphomas of the breast (PBL) are of B-cell phenotype. METHODS. Histologic and immunohistochemical analyses of seven patients with PBL and a statistical analysis of 152 patients with PBL reported in the Japanese literature were performed. RESULTS. Malignant lymphoma could not be predicted preoperatively with clinical and radiologic findings; breast carcinoma, fibroadenoma, and phyllodes tumor were the preoperative diagnoses. All patients were women; they ranged in age from 31 to 80 years (mean, 57.6 years). The right breast was involved initially in five patients. In four, only the breast was involved (Stage I), whereas in three, the ipsilateral axillary lymph nodes (Stage II) were involved at diagnosis. According to the Working Formulation, all patients belonged to the intermediate grade and were classified as having diffuse large cell (five patients) or mixed (two patients) lymphoma. Immunophenotypic analysis revealed that all patients had B-cell lymphoma. No patients had lymphoepithelial lesions, which is the characteristic feature in categorizing a lymphoma as a mucosa-associated lymphoid tissue (MALT) lymphoma. A statistical analysis of the patient reported in the Japanese literature has divided PBL into two types: a bilateral type that affects younger women and a unilateral type that has a broad age distribution, but preponderantly occurs in older women. The age and stage at diagnosis were significant prognostic factors in predicting the survival time, but the location and size of the tumor at initial presentation, histopathologic type, terminal leukemic manifestation, and treatment modality were not. CONCLUSIONS. This study indicates that most PBL are diffuse large cell lymphoma of B-cell phenotype and that the age and stage at diagnosis are significant prognostic factors. 相似文献