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61.
In this study, the effect of combining anti-CD4 monoclonal antibody (mAb) and cyclosporin (CyA) therapy at the time of transplantation was examined. A mouse cardiac allograft model was used. Anti-CD4 mAb administered perioperatively induces long-term survival. The addition of a short course of CyA given subcutaneously in a regimen of either a high-dose treatment or a standard dose treatment to the anti-CD4 mAb treatment protocol did not have a detrimental effect on graft survival. Despite having no significant effect on graft survival, the addition of CyA to the treatment protocol did result in a significant decrease in the level of IL-2 present in the hearts 7 days after transplantation. The decrease in IL-2 production was directly related to the presence of CyA in vivo. When CyA treatment was continued throughout the period during which unresponsiveness to the graft is induced by anti-CD4 mAb therapy, 50 % of the grafted hearts were rejected once the CyA was discontinued. In conclusion, the combined use of anti-CD4 mAb therapy and CyA did not have a negative effect on graft survival in this model when the two agents were used concurrently at the time of transplantation. Received: 2 October 1996 Received after revision: 31 January 1997 Accepted: 5 February 1997  相似文献   
62.
Three xenografts established from three patients with anaplastic thyroid carcinoma were investigated for their biological characteristics and chemosensitivity. The histological and immunohistochemical findings of these tumors were almost the same as those of the original tumors. Although the growth rate of each xenograft was constant, the tumor doubling time varied from 4.8 per 9.0 days, and the labeling indexes, determined using bromodeoxyuridine pulse labeling, varied from 11.4 to 25.1 per cent. The chemosensitivity tests were performed according to the Battelle Columbus Laboratories Protocol, with adriamycin, cyclophosphamide, cisplatin, mitomycin C and tegafur administered intraperitoneally to tumor-bearing nude mice in maximum tolerable doses. Tumors with slower growth rates tended to be sensitive to more drugs. Furthermore, cyclophosphamide showed antitumor effects against all the tumors tested. Although previous treatments of the original tumors may have affected the results, our results suggest that a more suitable chemotherapy for anaplastic thyroid carcinoma could be developed.  相似文献   
63.
Abstract: We analyzed the expression of CEA, CA19-9, CA125, CA15-3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19-9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15-3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19-9, CA15-3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19-9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15-3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15-3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15-3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas.  相似文献   
64.
The effect of sodium 6-(2-(1-(1H)-imidazolyl)methyl-4,5-dihydrobenzo(b) thiophene)carboxylate (RS-5186), a potent and long acting thromboxane synthetase inhibitor in vitro and in vivo, on infarct size and on the infiltration of polymorphonuclear leukocytes (PMNs), was studied in a rabbit coronary artery occlusion (1 h)--reperfusion (0.5 h or 3 h) model. The infarcted region was stained with triphenyltetrazolium, and the ratio of infarcted area/left ventricular area was calculated. The infiltration of PMNs into the infarcted region was determined by measuring the PMNs specific enzyme, myeloperoxidase (MPO) activity. In the vehicle treated group, infarct size and MPO activity were increased with increased reperfusion time from 0.5 h to 3 h (infarct size: 15.3 +/- 2.7 to 25.2 +/- 3.2%; MPO activity: 255 +/- 51 to 825.3 +/- 169.4 units/g wet weight). There was also a significant correlation (r = 0.90, p less than 0.01) between the infarct size and MPO activity. In contrast, in the RS-5186 treated group (2 mg/kg i.v.), both infarct size and MPO activity did not increase with prolongation of the reperfusion period (infarct size: 12.8 +/- 5.5 to 10.3 +/- 3.6%; MPO activity: 318.8 +/- 36.7 to 381.2 +/- 72.6 units/g wet weight). In 0.5 h reperfused samples, there was no significant difference in infarct size or in MPO activity between the vehicle treated group and RS-5186 treated group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
65.
A 72-year-old female visited our hospital with the complaint of macroscopic hematuria on Jan. 29, 1990. Cystoscopic examination revealed hematuria flowing out from the left ureteral orifice. A 1 cm mass was found in the left upper calyx by retrograde pyelography (RP). Urine cytology obtained by RP was class IIIb. Later, the mass was found in the left middle calyx by CT. Repeated RP revealed no mass and the wall of the left upper calyx was irregular. Washing cytology from the left renal pelvis was class V. Left total nephroureterectomy was performed on Feb. 2, 1990. Macroscopically, no tumor mass was apparent. Microscopically, transitional cell carcinoma in situ was widely spread from the left renal pelvis to the middle ureter. The preoperative upper calyceal mass was thought to have been a blood clot. At twelve months after the operation, there has been no evidence of tumor recurrence.  相似文献   
66.
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.  相似文献   
67.
A 14-year-old junior high school boy was admitted to our institute. Previously he had been diagnosed as having peripheral pulmonary stenosis (Gay's classification, type IV) at the age of 2 years and 10 months. On this occasion, however, a diagnosis of supravalvular aortic stenosis was made, with a pressure gradient of about 120 mmHg, and all examinations showed spontaneous remission of peripheral pulmonary stenosis. He underwent a successful standard aortoplasty. This is the first reported case of spontaneous remission of peripheral pulmonary stenosis.  相似文献   
68.
The induction of gastric tumor and intestinal metaplasia was examined in 8-week-old male JCL/SD rats exposed to localized X-irradiation of the gastric region. The animals were each given two 20 Gy fractions of X-rays, with a one-week interval between fractions (total, 40 Gy). Nine atypical hyperplasias (20%) and 13 adenocarcinomas (28%) in the pyloric mucosa of the glandular stomach were found in 46 animals with X-irradiation. The incidence of intestinal metaplasia was 93% in the pyloric mucosa, 50% in the fundic mucosa and 96% in both the pyloric and fundic mucosa. Type B metaplasia (intestinal metaplasia without Paneth cells) was most common and type C (intestinal metaplasia with Paneth cells) was less frequent. No gastric tumor or intestinal metaplasia appeared in non-irradiated control rats. This study shows that local X-irradiation of the gastric region induced both gastric tumor and intestinal metaplasia independently.  相似文献   
69.
Skip mediastinal nodal metastases in non-small cell lung cancer   总被引:1,自引:0,他引:1  
Objective: To reveal the incidence and clinical significance of mediastinal nodal metastases without N1-station nodal metastases (‘skip-N2 metastases’) in non-small cell lung cancer (NSCLC). Methods: A total of 450 NSCLC patients who underwent tumor resection with a systemic mediastinal nodal dissection were retrospectively reviewed. p53 status and proliferative activity represented as proliferative index (PI) were also examined immunohistochemically. Results: Skip-N2 metastases were documented in 49 (13%) patients of all 450 patients; among 334 patients without N1-nodal involvement, 18% patients had skip-N2 metastases. The postoperative survival of skip-N2 patients was almost same as that for patients with metastases to both N1 and N2 nodes. Skip-N2 metastases were significantly more frequent in male patients and squamous cell carcinoma patients. In addition, the mean PI for tumor with skip-N2 metastases was significantly higher than that for any other pathologic nodal (pN)-status diseases. Combined with histologic type and PI, the incidences of skip-N2 metastases for adenocarcinoma showing lower PI were only 5% (7/137) of all patients and 7% (7/94) of patients without N1-nodal involvement. Conclusions: N1 nodal status is not a useful predictor of N2 nodal status in NSCLC, because skip-N2 metastases were documented in 18% patients showing no N1-nodal involvement. However, N1 node-guided dissection might be performed in patients with adenocarcinoma showing lower PI, because the incidence of skip-N2 metastases was extremely low.  相似文献   
70.
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis.  相似文献   
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