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991.
992.
A cDNA clone for an auxin-regulated gene was isolated from a tobacco mesophyll protoplast cDNA library by differential screening. Nucleotide, sequence analysis showed that the deduced product of the gene, which we have designated par, is hydrophilic and is composed of 220 amino acids. No significant homology to other known proteins was detected. The mRNA of the par gene is approximately 900 bases long and its accumulation was detected in cultured mesophyll protoplasts as early as 30 min after the addition of 2,4-dichlorophenoxyacetic acid to the culture medium. The par mRNA was not detected in leaves or freshly prepared protoplasts or in protoplasts in the absence of 2,4-dichlorophenoxyacetic acid. Expression of the par gene was detected at a low level in actively dividing BY-2 tobacco suspension culture cells. The conspicuous accumulation of par mRNA before the initiation of DNA synthesis in tobacco mesophyll protoplasts suggests that the par gene product could play a role in the initiation of meristematic activity in differentiated mesophyll cells.  相似文献   
993.
Gastrointestinal tract involvement is a rare complication of plasma cell neoplasia. We present a case of non-secretory type primary plasma cell leukaemia (PCL) with multiple gastric involvement. Dual surface antigen analysis of bone marrow cells revealed that atypical plasma cells coexpressed CD38 and myeloid antigen CD13. Upper gastrointestinal endoscopy disclosed multiple submucosal masses in the body of the stomach. Endoscopic biopsy specimens showed marked infiltration of atypical plasma cells consistent with a diagnosis of gastric involvement by PCL. Since CD13 antigen is identical to aminopeptidase N, a membrane-bound glycoprotein thought to be involved in the process of tumour invasion, CD13 expression on neoplastic plasma cells may be related to the gastric involvement in this patient.  相似文献   
994.
OBJECTIVE:: The possible involvement of eosinophils in primary biliary cirrhosis (PBC) has been suggested for many years. Activated eosinophils release basic granule proteins and are thought to be involved in the tissue damage of PBC. Eosinophil peroxidase (EPO) is one of the eosinophilic granule proteins and is toxic to epithelial cells. In this study, we examined whether autoantibodies to EPO are present in sera of patients with PBC and we evaluated the relationship between the presence of anti-EPO antibodies and the clinical features of PBC. METHODS:: Sera obtained from 61 patients with PBC, 31 patients with autoimmune hepatitis (AIH), 87 patients with chronic viral hepatitis (CVH), 27 patients with bronchial asthma, and 20 healthy controls were examined. Enzyme-linked immunosorbent assay (ELISA) and Western blot methods were used for detection of anti-EPO antibodies. RESULTS:: The mean OD value of anti-EPO antibodies, as determined by ELISA, was significantly (p<0.01) higher in patients with PBC (0.197+/-0.121) than in patients with AIH (0.124+/-0.077), CVH (0.090+/-0.038) or bronchial asthma (0.073+/-0.025) and in healthy controls (0.072+/-0.029). The results of ELISA showed that 32 (52.5%) of the 61 patients with PBC, 9 (29.0%) of the 31 patients with AIH, 7 (8.0%) of the 87 patients with CVH, and 1 (3.7%) of the 27 patients with bronchial asthma were positive for anti-EPO antibodies. In addition, PBC patients who were positive for anti-EPO antibodies had a significantly smaller number of peripheral eosinophils than did patients who were negative for anti-EPO antibodies (99.2+/-54.4cells/mul versus 176.9+/-117.5cells/mul, p<0.01). However, there was no correlation between the titers of anti-EPO antibodies and those of AMA or AMA-M2, ANA or serum levels of IgM. CONCLUSIONS:: This is the first report of the detection of anti-EPO antibodies in patients with PBC. Further study is needed to clarify the role of anti-EPO antibodies in the pathogenesis of PBC.  相似文献   
995.
OBJECTIVE: Transplantation of hematopoietic stem cells (HSCs) is usually accomplished through intravenous injection, a complex process that requires recognition of bone marrow vasculature and migration to a supportive microenvironment. Hence, some populations of HSCs, including cord blood (CB) Lin(-)CD34(-) stem cells, do not engraft well in bone marrow (BM) of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. In this study, we examined the effect of human stromal interactions on the properties of CB Lin(-)CD34(-) cells. MATERIALS AND METHODS: CD34 and CXCR4 expression on fresh CB Lin(-)CD34(-) cells and CB Lin(-)CD34(-) cells cocultured with human stromal cells were analyzed. Homing activity and engraftment of these cells were assessed using NOD/SCID mice. In an attempt to identify the stromal CXCR4-inducing factor, CB Lin(-)CD34(-) cells were cocultured with a noncontact culture system in the presence of several inhibitors. RESULT: Coculture with human stromal cells induced expression of CD34 and CXCR4 on CB Lin(-)CD34(-) cells. CXCR4 expression on CB Lin(-)CD34(-) cells was induced even in the noncontact culture condition, suggesting that this CXCR4-inducing factor is soluble. Moreover, CXCR4 induction was inhibited by the soluble Wnt inhibitor DKK1. Furthermore, these cells acquired homing activity and engrafted in the BM of NOD/SCID mice after intravenous injection. CONCLUSION: These findings may be useful for understanding the role of stromal cells in homing and engraftment of HSCs.  相似文献   
996.
We describe a 66-year-old man having hepatocellular carcinoma with tumor thrombus extending into the inferior vena cava and synchronous pulmonary metastasis. He was referred to Chiba University Hospital on May, 2000, complaining of emaciation. Radiological findings showed a huge hepatocellular carcinoma in the entire right lobe and tumor thrombus extended into the intrapericardial inferior vena cava. He also had a solitary pulmonary metastasis in the left pulmonary lobe (stage IVB). Right hemihepatomy was performed under total hepatic vascular exclusion without cardiopulmonary bypass, and tumor thrombus was completely removed. Thoracoscopic wedge resection of pulmonary metastasis was also performed. The patient had an uneventful postoperative course. Histopathological examination revealed that the tumor was moderately differentiated hepatocellular carcinoma The patient is still alive after 26 months with pulmonary recurrence, but without hepatic recurrence. To our knowledge, there has been no reported case of resection for both hepatocellular carcinoma invading the inferior vena cava and synchronous pulmonary metastasis. In conclusion, aggressive surgical resection for advanced hepatocellular carcinoma concomitant with pulmonary resection may bring about better prognosis in highly selected patients.  相似文献   
997.
To improve the patency rate of radial artery grafts, we have been using a skeletonized harvesting technique since September 2000. Our early reports confirmed better graft patency of skeletonized radial graft compared to conventional pedicled grafts. We present the angiographic and clinical follow-up data on skeletonized radial artery grafting. Between 09/01/2000 and 7/31/2002, a total of 268 patients underwent isolated coronary artery bypass using skeletonized radial artery graft, excluding T-grafting. Of these, 216 (80.6%) patients underwent postoperative angiography and their perioperative, early angiographic, and follow-up results were analyzed. There was 1 hospital death and 6 incidences of postoperative myocardial infarction. None were related to radial artery bypass. Early angiographic control revealed that the stenosis-free graft patency rate of radial artery anastomoses (318/331, 96.1%) was not significantly different from other conduits (the left internal mammary artery 93.5%, right internal mammary artery 90.8%, gastroepiploic artery 96.3%, and saphenous vein 97.6%). Follow-up was completed for all hospital survivors with a mean follow-up of 1.6 ± 0.4 years. There were no cardiac deaths, and 9 cardiac events, giving a cardiac event-free rate of 95.8%. The angiographical patency of the skeletonized radial artery was excellent. Although cardiac events were minimal, follow-up mid-term angiographics will be necessary to confirm our clinical outcome data.  相似文献   
998.
Intracerebroventricular (ICV) injections of carbachol produced biphasic blood pressure responses consisting of initial vasodepression of short duration followed by a sustained pressor phase, which were accompanied by corresponding changes in sympathetic nerve activity in normotensive outbred-Wistar rats (NT) under urethane-anesthesia. In both normotensive Kyoto Wistar rats (WKY) and spontaneously hypertensive rats (SHR), on the other hand, carbachol elicited purely pressor responses, and accompanying sympathetic nerve activity was little affected. The magnitude of the pressor responses was larger in SHR than in WKY or NT rats. Spinal sectioning did not affect the magnitude of the pressor responses. Vasopressor responses to intravenous injections of arginine-vasopressin were not significantly different between WKY and SHR. These results indicate that carbachol injected intracerebroventricularly produces vasopressor effects mainly by releasing pituitary hormones, probably vasopressin, and that augmented pressor responses in SHR may be due to excessive release of vasopressin. When central noradrenergic neurons had been destroyed with ICV injections of 6-hydroxydopamine in both NT and WKY rats, carbachol-induced vasopressor responses were markedly augmented and resulted in responses similar to those of SHR. These findings indicate that central noradrenergic vasodepressive neurons are deficient and that the augmented vasopressor responses to carbachol resulted from deranged central noradrenergic mechanisms in SHR.  相似文献   
999.
Objective: The purpose of this study was to assess scrum type IV collagen 7-S domain (IV 7-S) levels in colorectal cancer patients with hepatic metastasis and to investigate the relation between serum IV 7-S levels and type IV collagenase activities in tumor tissue. Methods: Tissue type IV collagena.se activity and serum IV 7-S were measured in 50 colorectal cancer patients without hepatic metastasis and in 26 patients with hepatic metastasis. Results: Type IV collagenase showed significantly higher activities in colorectal cancer (n = 36) than in colorectal normal mucosa (n = 36) ( p < 0.001), but significantly lower activities were shown in the hepatic metastatic tumor (n = 18) than in the primary tumor (n = 36) and normal liver tissue (n = 18) ( p < 0.001). No significant correlation was (bund between type IV collagenase activities in the tumor and serum IV 7-S levels. Colorectal cancer patients with hepatic metastasis (n = 26) had significantly higher serum IV 7-S levels than those without hepatic metastasis (n = 50) ( p < 0.001). Moreover, serum IV 7-S levels correlated significantly with hepatic metastatic tumor volume in patients with synchronous ( r = 0.719, p < 0.001, n = 26) and in patients with metachronous ( r = 0.910, p < 0.001, n = 16) hepatic metastasis. Conclusion: We suggest that serum IV 7-S levels may increase in hepatic metastasis, not by the degradation of type IV collagen in the primary and secondary tumors, but by the enhanced production of type IV collagen responsive to hepatic metastasis. The measurement of serum IV 7-S levels might be a useful tumor marker of hepatic metastasis reflecting hepatic metastatic tumor volume.  相似文献   
1000.
Regan isoenzyme, variant alkaline phosphatase, and alpha-fetoprotein were found in the serum of a patient with gastric cancer. The histology of the tumor was tubular adenocarcinoma. There were metastases in the retroperitoneal lymph nodes, but not in the liver. The liver was normal microscopically, with no evidence of bile duct obstruction. alpha-Fetoprotein in the tumor tissue was detected by immunoprecipitation reaction in agar. Regan isoenzyme and variant alkaline phosphatase were also detected in the tumor tissue and total alkaline phosphatase activity of the tissue was very high. These findings suggested their tumor origin.  相似文献   
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