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81.
Tsukamoto F Shiba E Taguchi T Sugimoto T Watanabe T Kim SJ Tanji Y Kimoto Y Izukura M Takai SI 《Breast cancer (Tokyo, Japan)》1997,4(4):259-263
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR)
phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded
tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without
preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of
the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal
or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed
between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by
the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value
after radical operation. 相似文献
82.
83.
Masaaki Oka Shoichi Hazama Kazuhisa Hiwaki Sakurao Hiraki Akira Tangoku Kouji Shimoda Michinari Suzuki Norio Iizuka Kenji Wadamori Takashi Suzuki 《Journal of Hepato-Biliary-Pancreatic Surgery》1994,1(5):569-572
Interleukin-6 (IL-6) levels have been shown to correlate well with the magnitude of surgical stress. Serum IL-6 and plasma granulocytic elastase levels, 24 h after surgery, were determined in 12 patients who underwent open major surgery [MS group; esophageal carcinoma (n=5), gastric carcinoma (n=3), colorectal carcinoma (n=4) 5 patients who had open cholecystectomy [OC group] and 17 patients who had laparoscopic cholecystectomy [LC group]. IL-6 levels correlated significantly with the duration of surgery (r=0.685,P < 0.01) and with intraoperative blood loss (r=0.583,P < 0.02). However, there was no significant correlation between granulocytic elastase and the duration of surgery or blood loss. Plasma IL-6 levels in the LC group (21±3 pg/ml) were significantly lower than those in the OC group (47±5 pg/ml) and the MS group (186±36pg/ml) (P<0.05;P<0.01). However, there was no significant difference in granulocytic elastase levels between the LC group (318±8g/l), the OC group (360±130 gmg/ml), and the MS group (701±344 g/l). Increased IL-6 levels correlated well with increased duration of surgery. The lower IL-6 levels following laparoscopic cholecystectomy may therefore be indicative of lower surgical stress associated with laparoscopic cholecystectomy. 相似文献
84.
Tomosaburo Sakamoto Masahiko Miyata Makoto Nakamuro Masaaki Izukura Wataru Kamiike Hikaru Matsuda 《Surgery today》1994,24(12):1078-1080
A 51-year-old Japanese man who underwent a standard distal gastrectomy for cancer of the stomach developed abdominal pain when oral intake was commenced on the 6th postoperative day after an uneventful postoperative course. Complete obstruction of the jejunum led to a sudden deterioration in his general condition and a laparotomy was performed, revealing counterclockwise rotation of the mesenterium. The necrotic portion of the small intestine was removed, while 10 cm of the upper jejunum and 100 cm of the terminal ileum were preserved. His second postoperative course was uneventful apart from the development of intestinal hurry, which is now under medical control 9 months after his second laparotomy. 相似文献
85.
Proteolysis and invasiveness of brain tumors: Role of urokinase-type plasminogen activator receptor 总被引:2,自引:0,他引:2
Sanjeeva Mohanam Raymond E. Sawaya Masaaki Yamamoto Janet M. Bruner Garth L. Nicholson Jasti S. Rao 《Journal of neuro-oncology》1994,22(2):153-160
Summary The cellular receptor for urokinase-type plasminogen activator (uPAR) in glioblastoma cell lines has been identified and found to be similar to the uPAR expressed by other tumor cell lines. Increased levels of uPAR have been found in primary malignant brain tumor tissues, especially highly malignant glioblastoma, and, to a lesser degree, in malignant astrocytomas, suggesting that this receptor might be involved in efficient activation of pro-uPA and confinement of uPA activity on the cell surface of invading brain tumors. The cell surface uPARs in gliomas could constitute an optimum environment for the generation and activity of plasmin, which is known to play a crucial role in the dissolution of the extracellular matrix during tumor cell invasion.In situ hybridization studies have shown that uPAR mRNA is expressed abundantly in tumor cells and is consistently present at the invasive edges of malignant gliomas. These results imply that uPAR is involved in plasmincatalyzed proteolysis during glioma invasion and that interference with the uPAuPAR interactions could constitute a novel approach for developing therapeutic strategies to counteract invasion of brain tumors. 相似文献
86.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
87.
Kishimoto M Sano H Chang F Kawamori R Kamada T Tang BK Inaba T 《American journal of therapeutics》1995,2(1):47-49
Acetohexamide, an oral antidiabetic agent, is metabolized by carbonyl reductase to hydroxyhexamide, which has a higher hypoglycemic potency than the parent compound. In the present study, interindividual variability of carbonyl reductase activity in erythrocyte was examined. Enzyme activity in 31 healthy subjects (23.9 plus minus 3.4 years, mean plus minus SD) was monitored by measuring formation of hydroxyhexamide using HPLC methods. Using 0.5 mM acetohexamide as substrate, reductase activity of 6.06 plus minus 0.06 nmol min(minus sign1) gHb(minus sign1) (range: 5.9--6.2) with a coefficient of variation of 15% was observed in erythrocytes. Acetohexamide-reducing activity in erythrocytes showed a normal distribution and the interindividual variability of the reductase activity was found to be small, implying that the large variability reported for the acetohexamide plasma half-life is not caused by the amount of reductase enzyme in erythrocytes. 相似文献
88.
S Inaba H Hirayama C Nagata Y Kurisu N Takatsuka N Kawakami H Shimizu 《Preventive medicine》1999,29(2):102-106
BACKGROUND: Systematic population-based screening for gastric cancer is widely spread in Japan. However, the case-control study method has been the main method used to evaluate the effectiveness of the screen ing to reduce gastric cancer mortality in Japan. METHODS: This article presents a population-based cohort study. A questionnaire about lifestyles and dietary habits was distributed to 36,990 residents in a city of Japan. The response rate to the questionnaire was 92.0%. After ineligible responders had been excluded, 24,134 subjects were classified into screened and un screened groups according to their self-reports of participation in the screening the previous year. We followed them up for 40 months and linked resident death records in the city. We compared mortality from gastric cancer and all other causes between the groups by us ing the Cox proportional hazard model. RESULTS: The follow-up period was 78,156.6 person-years from September 1992 to December 1995. The multivariate relative risks for gastric cancer death of the screened group in comparison with the unscreened group were 0.72 (95% CI 0.31-1.66) among males and 1.46 (95% CI 0.43-4.90) among females. CONCLUSION: Although our data are preliminary, we were unable to demonstrate a large contribution of the present screening program to decreasing gastric cancer mortality. Further follow-up is needed to in crease the precision. 相似文献
89.
This report reviews the biological effects and case reports of suicidal or accidental ingestion of, and occupational exposure to sodium azide. Ingested doses of sodium azide were estimated for the 6 survival and 4 fatal cases studied. The lowest dose among survival cases was 5-10 mg. The patient reported headache, sweating, and faintness within approximately 5 minutes of ingestion. Four victims ingested 20 to 40 mg and recovered within 2 hours. However, a man who took 80 mg reported chest pain for 6 months after ingestion. The smallest doses among fatal cases were 0.7-0.8 g for women and 1.2-2 g for men. All victims suffered from hypotension, tachycardia, hyperventilation, diaphoresis, vomiting, nausea, and diarrhea. There is no antidote for sodium azide. Detoxicants for cyanide such as sodium nitrite or thiosulfate were tried, but were unfortunately, ineffective. Sodium nitrite may worsen the hypotension caused by sodium azide, and is not recommended. Occupational exposure to sodium azide is thought to be common, however, fatal exposure is rare. NIOSH "Recommended Exposure Limits" for sodium azide is 0.3 mg/m3. 相似文献
90.
Nishiyama M Nakae K Yukawa S Hashimoto T Inaba G Mochizuki M Sakane T 《Environmental health and preventive medicine》1999,4(3):130-134
The 4th nationwide epidemiological survey on Behçet disease (BD), which included all patients with BD at 1,200 hospitals selected at random from 10,081 hospitals in Japan, was carried out by the BD Research Committee of the Ministry of Health and Welfare in 1991 to examine the epidemiological features of BD in Japan by comparing with previous surveys. 3,938 patients from these hospitals were examined by the Japanese diagnostic criteria of BD (JCBD) revised in 1987 and the International criteria for classification of BD (ICBD). Among these 3,938 patients, 622 patients were only suspected of having BD or clinical signs of the disease were unknown, and most of these patients were incompatible with the ICBD. So these patients were excluded from the study of epidemiological features. The average patients age has risen 7–8 years over the last 20 years and the average age of onset in both sexes increased by about 3 years from 1972 to 1991. While a decrease in the sex ratio was seen in the complete-type and the incomplete-type BD without ocular symptoms, a sustained high sex ratio was shown in incomplete-type BD with ocular symptoms. The positive rate of HLA-B51 antigen was 54.9% (men: 56.9%, women: 52.2%) significantly higher than die 15–16% in healthy subjects but it might have been gradually decreasing. Also the clinical course of BD has become too mild for prognosis. According to diese epidemiological features of BD, the clinical manifestation of BD in Japan might have become the Western type of BD. 相似文献