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31.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992.  相似文献   
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There is some evidence that the sympathetic nervous system plays a role in the development and/or maintenance of painful states, and that sympathetic nervous function is altered in these conditions. Our previous experiments showed that electrical stimulation of the lumbar sympathetic trunk (sympathetic stimulation: SS), which normally induces a decrease in blood flow (BF) of plantar skin, induced its BF increase in about 50% of adjuvant-inflamed rats. To investigate the mechanism of this BF-increase response, we examined whether noradrenaline (NA) plays any role in this changed response to SS, and which receptor subtype is involved. We measured paw cutaneous BF response with a laser Doppler flowmeter in rats chronically inflamed with complete Freund's adjuvant. SS induced the BF-increase response in 50-67% of measured sites. Close-arterially injected NA induced the BF-increase response at dosages between 10-100 ng/kg only at the sites with the BF-increase response to SS. The BF-increase and -decrease responses to NA was significantly reduced after the close-arterial injection of either alpha1- or alpha2-adrenoceptor antagonists (p lt; 0.05, respectively). In contrast, although the BF-decrease responses to SS were significantly reduced by administration of alpha1- and alpha2-adrenoceptor antagonist, BF-increase response was reduced only by alpha1-adrenoceptor antagonist, and that only at a higher dose. In addition, the beta-adrenoceptor antagonist had no effects on both responses. These results suggest that the BF-increase response to SS involves, additionally to NA, a non-adrenergic mechanism.  相似文献   
36.
Malignant rhabdoid tumor (MRT) is a highly malignant pediatric cancer, which arises in various sites such as the kidney, brain, and soft tissues. Cytogenetic studies have revealed alterations of 22q11 in MRT. Recently, deletions and mutations of the SNF5/INI1 locus in 22q11.2 have been reported in MRT, suggesting that SNF5/INI1 is a tumor suppressor gene for MRT. Here we report our molecular cytogenetic study for a newly established cell line from extrarenal MRT with t(1;22)(p36;q11.2). Consequently, the reciprocal translocation was associated with the interstitial deletion of a small segment including SNF5/INI1, and another, chromosome 22, showed terminal deletion, the breakpoint of which was located 70–80 kb centromeric to SNF5/INI1, resulting in homozygous deletion of SNF5/INI1 in this cell line.  相似文献   
37.
Glucose-responsive (GR) neurons in the hypothalamus are thought to be critical in glucose homeostasis, but it is not known how they function in this context. Kir6.2 is the pore-forming subunit of K(ATP) channels in many cell types, including pancreatic beta-cells and heart. Here we show the complete absence of both functional ATP-sensitive K+ (K(ATP)) channels and glucose responsiveness in the neurons of the ventromedial hypothalamus (VMH) in Kir6.2-/- mice. Although pancreatic alpha-cells were functional in Kir6.2-/-, the mice exhibited a severe defect in glucagon secretion in response to systemic hypoglycemia. In addition, they showed a complete loss of glucagon secretion, together with reduced food intake in response to neuroglycopenia. Thus, our results demonstrate that KATP channels are important in glucose sensing in VMH GR neurons, and are essential for the maintenance of glucose homeostasis.  相似文献   
38.
There is disagreement among researchers concerning whether glutamatergic N-methyl-D-aspartate (NMDA) receptors play a role in constructing spatial representations. Therefore, the authors reexamined the effects of the NMDA antagonist on a spatial discrimination task using rats in a water pool. The authors confirmed that MK-801 impaired acquisition of the spatial discrimination task (Experiment 1). When rats were pretrained before drug treatment, MK-801 induced learning deficits in the novel environment but not in the familiar environment (Experiment 2). Moreover, in a familiar environment, MK-801 did not impair spatial learning, even when the task was completely novel for the rats (Experiment 3). These results suggest that NMDA receptors play an important role in the construction of spatial representations but not in the use of them.  相似文献   
39.
 Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection. Received: 24 November 1998 / Accepted: 24 April 1998  相似文献   
40.
A 51 -year-old woman with mixed growth hormone (GH) cell-prolactin (PRL) cell pituitary adenoma is presented. She had clinical signs due to hypersecretion of GH and PRL. Resected tissue was studied immunohistochemically and morphologically. The serial sections revealed that GH and α-subunit were co-localized in most cells, while GH and PRL were localized in different cells.  相似文献   
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