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61.
During a sparrow-pecking and twisting-needle manipulation to the acupoints BL 23, 24 and 25 for an induction of "Qi", it was found that some transparent materials were binding to the needles after removed from the volunteer's skin. Electron-microscopical analysis of the transparent materials revealed that they corresponded to the injured fascia made up of collagen fibers, elastic fibers, fibroblasts, adipocytes and mast cells. Rarely were nerve fiber-like structures observed in the materials. Immunohistochemically, calcitonin gene-related peptide-positive nerve fibers could be demonstrated in the acupoint BL 24 associated fascia. A possible functional relationship between the needle manipulation and the induction of Qi-sensation is discussed along with the acupoint tissue constitution.  相似文献   
62.
A 53-year-old female presented with an unruptured, large basilar trunk aneurysm manifesting only as headache with no neurological deficits, including absence of cranial nerve dysfunction. Cerebral angiography disclosed a large aneurysm with a wide neck arising from the midbasilar artery. We treated the aneurysm surgically via the posterior petrosal approach. Five angled clips were applied sequentially to the aneurysm and the basilar artery was successfully reconstructed. Electrophysiological monitoring was continued during the operation and showed no changes. Following the operation, the patient suffered from transient right abducens nerve palsy, which persisted for 3 months. Postoperative angiography showed that the aneurysm was obliterated, and the patency of the basilar artery was preserved.  相似文献   
63.
A low serum phosphate concentration is characteristic in individuals in whom kidney stones form, this being related to serum 1,25-dihydroxyvitamin D, parathyroid hormone and urinary phosphate excretion. In order to determine whether these parameters are related to recurrence of stone formation, they were analyzed in single and recurrent stone formers as well as controls. An inverse correlation between serum levels of phosphate and 1,25-dihydroxyvitamin D was observed in control subjects, indicating that a drop in serum phosphate results in upregulated circulating 1,25-dihydroxyvitamin D level in controls. While the circulating low phosphate level upregulated the 1,25-dihydroxyvitamin D level in single stone formers, the elevation was less than expected from the drop in serum phosphate in recurrent stone formers. The results thus suggest that loss of upregulation of 1,25-dihydroxyvitamin D by serum levels of phosphate might be important for stone formation. The possibility of deregulation of 1,25-dihydroxyvitamin D to maintain physiological requirements in stone formers and prevent further nephrolithiasis therefore warrants attention. Received: 27 January 1999 / Accepted: 25 June 1999  相似文献   
64.
R Ohno  N Asou  K Ohnishi 《Leukemia》2003,17(8):1454-1463
Acute promyelocytic leukemia (APL) has become a curable disease by all-trans retinoic acid (ATRA)-based induction therapy followed by two or three courses of consolidation chemotherapy. Currently around 90% of newly diagnosed patients with APL achieve complete remission (CR) and over 70% of patients are curable. To further increase the CR and cure rates, detection and diagnosis of this disease at its early stage is very important, hopefully before the appearance of APL-associated coagulopathy. In induction therapy, concomitant chemotherapy is indispensable, except for patients with low initial leukocyte counts. Prophylactic use of intrathecal methotrexate and cytarabine should be done, particularly for patients with hyperleukocytosis. If patients relapse hematologically or even molecularly, arsenic trioxide will be the treatment of choice under careful electrocardiogram monitoring. Am80, liposomal ATRA, gemtuzumab ozogamicin or ATRA in combination with cytotoxic drugs may be used at this stage or later. Allogeneic SCT will be the treatment of choice after patients of age <50 years have relapsed, provided that they have HLA-identical family donors or DNA-identical unrelated donors.  相似文献   
65.
The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis.  相似文献   
66.
67.
Tumor lysis syndrome is a rare complication of nonhematologic malignancies that results from massive necrosis of neoplastic cells after chemotherapy. This syndrome consists of life-threatening metabolic derangements, including severe hyperphosphatemia, hyperkalemia, hyperuricemia, and hypocalcemia, and may result in renal failure and death if not recognized early and treated appropriately. We report a case of tumor lysis syndrome after induction chemotherapy in a patient with widely metastatic smallcell lung cancer. This case emphasizes the importance of awareness and early treatment of this syndrome.  相似文献   
68.
PURPOSE: To investigate whether nitric oxide excreted from cells irradiated with accelerated carbon-ion beams modulates cellular radiosensitivity against irradiation in human glioblastoma A-172 and T98G cells. MATERIALS AND METHODS: Western-blot analysis of inducible nitric oxide synthase, hsp72 and p53, the concentration assay of nitrite in medium and cell survival assay after irradiation with accelerated carbon-ion beams were performed. RESULTS: The accumulation of inducible nitric oxide synthase was caused by accelerated carbon-ion beam irradiation of T98G cells but not of A-172 cells. The accumulation of hsp72 and p53 was observed in A-172 cells after exposure to the conditioned medium of the T98G cells irradiated with accelerated carbon-ion beams, and the accumulation was abolished by the addition of an inhibitor for inducible nitric oxide synthase to the medium. The radiosensitivity of A-172 cells was reduced in the conditioned medium of the T98G cells irradiated with accelerated carbon-ion beams compared with conventional fresh growth medium, and the reduction of radiosensitivity was abolished by the addition of an inducible nitric oxide synthase inhibitor to the conditioned medium. CONCLUSIONS: Nitric oxide excreted from the irradiated donor cells with accelerated carbon-ion beams could modulate the radiosensitivity of recipient cells. These findings indicate the importance of an intercellular signal transduction pathway initiated by nitric oxide in the cellular response to accelerated heavy ions.  相似文献   
69.
PURPOSE: There have been no reports about the effects of heavy-ion beams on the expression of the WAF1 gene, although ionizing radiation such as y-rays and X-rays is well known to induce WAF1 (p21/CIP1/sdi1) gene expression in a p53-dependent manner. In the present study, it was examined whether WAF1 accumulation was induced after carbon-ion (C-) beam or alpha-particle irradiation in four glioblastoma cell lines. MATERIALS AND METHODS: A colony assay for radiosensitivity and Western blot analysis of WAF1 were applied to two human glioblastoma cell lines, A-172 bearing wild-type p53 (wtp53) and T98G bearing mutated p53 (mp53). A-172/neo and A-172/mp53 were transfected with a control vector (containing only a neo selection marker) and a mp53 expression vector respectively. RESULTS: The amount of WAF1 increased markedly after X-ray irradiation in A-172 and A-172/neo cells but not in T98G and A-172/mp53 cells. The level of WAF1 reached a plateau at 3-10 h after X-ray irradiation at 5 Gy in A-172 and A-172/neo cells. Likewise, the levels of WAF1 in A-172 and A-172/neo cells reached a plateau at 3-10 h and 6-24 h after C-beam (3.0 Gy) and alpha-particle (4.5 Gy) irradiation respectively. The amount of WAF1 increased markedly in a dose-dependent manner 10 h after X-ray, C-beam or alpha-particle irradiation in A-172 and A-172/neo cells but not in T98G or A-172/mp53 cells. In addition, cell survival assay showed that these cell lines were most sensitive to C-beams, less sensitive to alpha-particles and least sensitive to X-rays at 10% survival. There was no difference in sensitivity among these cell lines against C-beam and alpha-particle irradiation whereas wtp53 cells (A-172 and A-172/neo) were more sensitive to X-rays than mp53 cells (A-172/mp53 and T98G). CONCLUSIONS: These results indicate that C-beams and alpha-particles induce p53-dependent WAF1 accumulation as well as is the case with X-rays, suggesting that WAF1 protein accumulation may not contribute to cell killing.  相似文献   
70.
Tumor-associated antigens are promising candidates as target molecules for immunotherapy and a wide variety of tumor-associated antigens have been discovered through the presence of serum antibodies in cancer patients. We previously conducted dendritic cell therapy on 10 malignant melanoma patients and shrinkage or disappearance of metastatic tumors with massive necrosis occurred in two patients. In this study, we found a 29-kDa protein against which antibody was elicited by dendritic cell therapy in one of the two patients. Matrix-assisted laser desorption ionization-time of flight/mass spectrometry analysis of the protein isolated by two-dimensional electrophoresis combined with Western blots revealed that the 29-kDa protein was carbonic anhydrase II (CA-II). Immunohistochemistry of the tumors and normal tissues showed that CA-II was expressed in the tumor vessel but not in normal vessel endothelium. CA-II expression in tumor endothelium was observed as well in other cancers including esophageal, renal, and lung cancers. In an in vitro angiogenesis model, CA-II expression of normal human vein endothelial cells was significantly up-regulated when cells were cultured in the acidic and hypoxic conditions indicative of a tumor environment. These findings suggest that CA-II is a tumor vessel endothelium-associated antigen in melanoma and other cancers, and elicitation of serum anti-CA-II antibody by dendritic cell therapy may be associated with good clinical outcome including tumor reduction.  相似文献   
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