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Eight cell lines were established from patients with adult T-cell leukemia, and from normal adults, by cocultivation with human T-cell leukemia virus type I(HTLV-I)-producer cell lines in the presence of interleukin-2. All of these cell lines harbored HTLV-I and showed T-cell markers CD2, CD3 and CD4, hut not B-cell markers. Unexpectedly, all eight cell lines expressed a myeloid marker CD13 and three of the eight lines also expressed another myeloid marker CD33. Dual staining showed the simultaneous expression of CD3 and CD13 on the same cells. Thus, evidence was obtained for the expression of myeloid antigens on HTLV-I-harboring T cells.  相似文献   
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Subacute nephrotoxicity of germanium dioxide in the experimental animal   总被引:2,自引:0,他引:2  
Germanium (Ge; atomic number 32, atomic weight 72.6) belongs to IVb group of the Periodic Table and is found as a trace metal in soil, rocks, plants, and animals. It is widely used in industry because of its semiconductive nature. Some biological activities have been shown in Ge derivatives. Recently, patients with persistent renal damage after chronic ingestion of germanium dioxide (GeO2)-containing compounds have been reported in Japan. This study aimed to investigate subacute nephrotoxicity of GeO2 in Lewis male rats. The rats were treated orally with GeO2 for 13 weeks (GeO2 group) and were compared with those treated with GeO2 for only the first 4 weeks (GeO2-4-week group) and with untreated controls. Renal dysfunction was demonstrated by the increased serum creatinine, BUN, and serum phosphate and decreased creatinine clearance. Liver dysfunction was observed as demonstrated by the increased GOT and GPT, and hypoproteinemia by the decreased total protein and albumin in the GeO2 group. However, daily urinary protein excretion or urinalysis did not differ among the groups. Kidney weight and Ge content of tissues were significantly elevated in the GeO2 group. With the light microscope, vacuoles and the depositions of PAS-stained particles, which correspond to electron-microscopic dense granules in the swollen mitochondria, were predominantly observed in distal tubular epithelium in the GeO2 group. Even in the GeO2-4-week group of rats, serum creatinine was increased and the above-mentioned histological abnormalities were observed, but were less intense.  相似文献   
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PURPOSE: We evaluated the clinical significance of hypofractionated high-dose irradiation using simultaneous integrated boost technique with intensity-modulated radiation therapy (IMRT) for the treatment of malignant astrocytomas (MAs). METHODS AND MATERIALS: Twenty-five patients with MAs were treated by IMRT. Three layered planning target volumes (PTVs) were contoured. PTV-1 was the area of enhanced lesion with 5-mm margin; PTV-2 was the area with 15-mm margin surrounding the PTV-1; PTV-3 was the area of perifocal edema. Irradiation was performed in 8 fractions, and only the dose for PTV-1 was escalated from 48 Gy to 68 Gy while maintaining the dose for PTV-2 (40 Gy) and PTV-3 (32 Gy). The clinical outcome of IMRT was compared with 60 MA patients treated by conventional external beam irradiation (EBI). RESULTS: The progression-free survival of patients in the IMRT group was significantly longer than that in the EBI group (p < 0.0001). No distant failure was observed in both groups. In the IMRT group, dissemination was the most frequent cause of death (70%). The overall survival of patients in the IMRT group was better than that in the EBI group (p = 0.043). CONCLUSIONS: Our regimen of IMRT contributed to the control of both the regional and infiltrating tumors, resulting in better survival of patients.  相似文献   
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Inherited thrombocytopenia is a genetically heterogeneous disease characterized by varying degrees of thrombocytopenia and risk of haematological malignancy, and the genetic cause of many cases remains unknown. We performed whole-exome sequencing of a family with thrombocytopenia and myeloid malignancy and identified a novel TUBB1 variant, T149P. Screening of other thrombocytopenia pedigrees identified another TUBB1 variant, R251H. TUBB1 encodes the tubulin β-1 chain, a major component of microtubules abundant in megakaryocytes. Variant TUBB1 disrupted the normal assembly of microtubules and impaired proplatelet formation in vitro. In addition, DNA damage response was severely attenuated by loss of TUBB1. We found that the nuclear accumulation of p53 (also termed TP53) and the expression of pro-apoptotic genes triggered by genotoxic stress were blocked in TUBB1-deficient cells and, accordingly, apoptosis after DNA damage was diminished by knockdown of TUBB1. Thus, we have demonstrated that microtubule dysfunction confers resistance to apoptosis, even in DNA damage-accumulated cells, which explains genome instability in the affected individuals. These studies will lead us to a better understanding of how microtubule dysfunction can contribute to the accumulation of DNA damage, genetic instability and leukaemogenesis.  相似文献   
59.
Although the mean score of the Children's Sleep Habits Questionnaire (CSHQ) differs between countries, there are no normative data for the CSHQ of Japanese preschoolers based on a community sample. The aims of this study were therefore to present normative data for the CSHQ and determine the prevalence and characteristics of sleep problems in Japanese preschoolers. Parents or the primary caregiver of 482 preschoolers aged 4–5 years completed the CSHQ and the Strength and Difficulties Questionnaire. Approximately 80% of preschoolers scored above the cut‐off for sleep disturbance on the CSHQ. In addition, co‐sleeping was prevalent in Japanese preschoolers but the habit of co‐sleeping contributed little to behavioral and emotional problems. Sleep problems appear to be prevalent in Japanese preschoolers based on the CSHQ, and could be associated with the Japanese sleep habit of co‐sleeping.  相似文献   
60.
The sensitivities to penicillins and to a penicillin and beta-lactamase inhibitor combination agent were determined for Helicobacter pylori strains that were sensitive, moderately resistant, or highly resistant to amoxicillin. All strains were resistant to nafcillin and oxacillin. Moderately resistant strains showed an intermediate zone of inhibition to ticarcillin, mezlocillin, piperacillin, and amoxicillin-clavulanic acid. High-level resistance was associated with the smallest zone size for all penicillins tested.  相似文献   
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