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1.
Antigen presentation by a B-cell line transfected with cloned immunoglobulin heavy- and light-chain genes specific for a defined hapten. 总被引:5,自引:1,他引:4 下载免费PDF全文
M Watanabe D R Wegmann A Ochi N Hozumi 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(14):5247-5251
The rearranged genes encoding immunoglobulin heavy (mu) and light (kappa) chains specific for the hapten 2,4,6-trinitrophenyl (Tnp) were introduced into a B-lymphoma line that bears surface IgG with an unknown specificity and expresses surface Ia molecules. A transformant expressing surface IgM specific for Tnp was obtained. The transformant was found to present Tnp-proteins to antigen (protein)-specific T cells far more efficiently than the parenteral B-lymphoma line. This artificial system, utilizing recombinant DNA technology and gene transfer, provides several approaches for the study of T-cell-B-cell interactions. 相似文献
2.
3.
Yuji Maruyama Shigeo Yamauchi Hidetsugu Ogasawara Hajime Imura Masami Ochi Kazuo Shimizu 《Annals of thoracic and cardiovascular surgery》2006,12(1):60-62
Surgical treatment for subacute pulmonary arterial thromboembolism has previously been considered to be inappropriate. We undertook a pulmonary arterial thrombectomy and removal of a floating right heart thrombus in a patient who had been symptomatic for over a month. The pulmonary arterial pressure, which had been equal to the systemic pressure preoperatively, decreased gradually and almost normalized one month postoperatively. Pulmonary perfusion scintigraphy revealed a dramatic improvement and the patient returned to normal life activities. 相似文献
4.
Hirofumi Nakanishi Akira Myoui Takahiro Ochi Katsuyuki Aozasa 《Journal of cancer research and clinical oncology》1997,123(6):352-356
Multidrug resistance (MDR) is an important problem in chemotheraphy for neoplastic disease. In humans, MDR is mainly mediated by P-glycoprotein (P-gp), a product of theMDR1 gene, which acts as a transmembrane protein pump and eliminates chemotherapeutic agents from the cells. Expression of P-gp was immunohistochemically studied by using two monoclonal antibodies, JSB-1 and C-219, on paraffin-embedded sections from 55 patients with soft-tissue sarcoma. The histological diagnosis of tumors was malignant fibrous histiocytoma in 24 cases, liposarcoma in 9, synovial sarcoma in 7, malignant neurogenic tumors in 6, leiomyosarcoma in 5, others in 4. The histological grade was determined on the basis of criteria previously proposed by us. Out of 55 cases, 34 (62%) were positive for P-gp expression. There was a significant difference in P-gp expression between high-grade (90%) and intermediate and low-grade tumors (46%) (P<0.005). Tumors expressing P-gp had a less favorable prognosis than P-gp-negative tumors in the high- and intermediate-grade tumors. The current study demonstrated that the estimation of P-gp expression could be used to select appropriate therapeutic modalities.Abbreviations
MDR
multidrug resistance
-
P-gp
P-glyco-protein 相似文献
5.
S Shibata A Ochi H Yamashita A Yasunaga K Mori 《No shinkei geka. Neurological surgery》1990,18(6):527-531
The tumor vessels of a primary meningeal malignant melanoma were studied by electron microscopy. There were numerous endothelial fenestrae and basal lamina abnormalities in the intrinsic tumor capillaries. They resembled the tumor vessels found in nonglial tumors, but were distinctly different from those seen in glial tumors with nonfenestrated capillaries. These findings were anticipated because leptomeninges have fenestrated capillaries. 相似文献
6.
The effects of prior 24-hour ureteral obstruction on ischemic renal damage were studied in rats. Rats were divided into 6 groups with different times of ischemia (0, 60 and 90 min) and with or without 24-hour ureteral obstruction. Following a 4-week recovery period, contralateral nephrectomy was performed and the rat was sacrificed 24 h later for the determination of serum creatinine and for histologic examination of the affected kidney. A preceding ureteral obstruction for 24 h made no difference to the renal damage with 60 min of ischemia or without ischemia. However, kidneys with 90 min of ischemia and 24 h of ureteral obstruction were more damaged than those with 90 min of ischemia only. These results suggested that the hydronephrotic kidney was more susceptible to long periods of ischemia than the normal kidney. 相似文献
7.
Takashi Natsuume Norimasa Nakamura Konsei Shino Yukiyoshi Toritsuka Shuji Horibe Takahiro Ochi 《Journal of orthopaedic research》1997,15(6):837-843
We investigated the temporal and spatial expression of transforming growth factor-β in the healing patellar ligament of the rat by immunohistochemistry. The mid-portion of the medial half of the patellar ligament in 14-week-old male Wistar rats was cut transversely with a scalpel. On day 1 after ligament injury, diffuse staining for transforming growth factor-β was observed in the extracellular matrix filling the wound, and the staining in the adjacent ligament tissue was as weak as it was in the normal ligament. On day 3, the intensity of the diffuse extracellular staining decreased, and the staining was observed in correspondence with the cellular distribution in the wound site and in the adjacent uninjured ligament tissue. On day 7, the intense staining was widely distributed over the whole length of the ligament tissue. On day 28, the staining for transforming growth factor-β was still observed at the wound site and in the adjacent uninjured ligament tissue, where the staining was reduced in intensity but still stronger than it was in the normal ligament. On day 56, the expression of transforming growth factor-β was still detectable at the wound site: however, in the adjacent uninjured ligament tissue, it had almost subsided to the normal level. The results of the present study suggest that ligament healing may be accompanied by extensive changes in the expression of transforming growth factor-β over the whole length of ligament tissue. 相似文献
8.
Clinical Evaluation of a New Type of Centrifugal Pump 总被引:2,自引:0,他引:2
J. Ninomiya T. Shoji S. Tanaka M. Ikeshita M. Ochi S. Yamauchi T. Yajima H. Yamauchi T. Sugimotox T. Aizawa 《Artificial organs》1994,18(9):702-705
Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass. 相似文献
9.
Myocardial protective effect of lidocaine during experimental off-pump coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Kazuhiro Hinokiyama Nobuo Hatori Masami Ochi Tadaaki Maehara Shigeo Tanaka 《Annals of thoracic and cardiovascular surgery》2003,9(1):36-42
Off-pump coronary artery bypass grafting (OPCABG) has recently gained popularity. During OPCABG, patients remain vulnerable to ischemic-reperfusion injury due to a temporary coronary occlusion without any active cardioprotection. Some strategies such as ischemic preconditioning (IP) and an intracoronary shunt have been applied with a view to minimizing the effects of ischemia, but the effects of these strategies remain controversial. This study was carried out to investigate the protective effect of lidocaine against myocardial ischemic-reperfusion injury. Twenty-one pigs were assigned to three groups, each consisting of seven pigs. In the control group, using a left internal thoracic artery (LITA) bypass circuit, the left anterior descending coronary artery (LAD) was occluded for 45 min followed by two hours of reperfusion. In the IP group, five min of occlusion followed by 15 min of reperfusion was performed. In the lidocaine group, 2 mg/kg of lidocaine was administered directly into the LAD just before the LAD occlusion. Infarct size expressed as a percentage of the area at risk was significantly smaller in the lidocaine group (2.7+/-4.2%) than in the control group (79.9+/-6.0%, p<0.001) or the IP group (57.0+/-25.9%, p<0.001). Lidocaine exhibited a potent myocardial protective effect in the present OPCABG model. 相似文献
10.
Crystal-matrix interrelations in brushite and uric acid calculi 总被引:1,自引:0,他引:1
Brushite and uric acid calculi were studied by means of scanning electron microscopy with the partial dissolution method and transmission electron microscopy. Brushite calculi consist of radially oriented columnar crystals which have sheet-like substructure. The organic matrix is identified chiefly at the outside of the crystals but partly included between the substructure. The concentric matrix bands are often dislocated between the neighbouring crystals. Uric acid calculi also consist of radially oriented columnar crystals, and a fine meshwork of the organic matrix is incorporated within the crystals. The concentric matrix layers of different density are angled according to the crystal lattice. These findings indicate that the organic matrix arose from a mucinous surface coat, at least in the radially striated calculi. The crystals continued to grow in this gel-state milieu, either thrusting the matrix aside or incorporating it within the crystals. 相似文献