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91.
Briddell  RA; Hartley  CA; Smith  KA; McNiece  IK 《Blood》1993,82(6):1720-1723
Splenectomized mice treated for 7 days with pegylated recombinant rat stem cell factor (rrSCF-PEG) showed a dose-dependent increase in peripheral blood progenitor cells (PBPC) that have enhanced in vivo repopulating potential. A dose of rrSCF-PEG at 25 micrograms/kg/d for 7 days produced no significant increase in PBPC. However, when this dose of rrSCF-PEG was combined with an optimal dose of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 200 micrograms/kg/d), a synergistic increase in PBPC was observed. Compared with treatment with rhG-CSF alone, the combination of rrSCF-PEG plus rhG-CSF resulted in a synergistic increase in peripheral white blood cells, in the incidence and absolute numbers of PBPC, and in the incidence and absolute numbers of circulating cells with in vivo repopulating potential. These data suggest that low doses of SCF, which would have minimal, if any, effects in vivo, can synergize with optimal doses of rhG-CSF to enhance the mobilization of PBPC stimulated by rhG-CSF alone.  相似文献   
92.
Benis  KA; Schneider  GB 《Blood》1996,88(8):2898-2905
Osteopetrosis is a heterogeneous group of bone disorders characterized by the failure of osteoclasts to resorb bone and by several immunological defects including macrophage dysfunction. Two compounds, colony-stimulating factor-1 (CSF-1) and vitamin D-binding protein- macrophage activating factor (DBP-MAF) were used in the present study to evaluate their effects on the peritoneal population of cells and on cells within the bone marrow microenvironment in normal and incisors absent (ia) osteopetrotic rats. Previous studies in this laboratory have demonstrated that administration of DBP-MAF to newborn ia animals results in a substantial increase in bone marrow cavity size due to upregulated osteoclast function. To study the effects of these compounds on the macrophage/osteoclast precursors, DBP-MAF, CSF-1, and the combination of these compounds were given to newborn ia and normal littermate animals. Both the normal and mutant phenotypes responded similarly when treated with these compounds. Rats exhibited a profound shift toward the macrophage lineage from the neutrophil lineage when compared with vehicle-treated control animals after treatment with these compounds. In the in vivo peritoneal lavage study, animals received injections of CSF-1, DBP-MAF or DBP-MAF/CSF-1 over a 4-week period. The various types of cells in the peritoneal cavity were then enumerated. The in vitro study consisted of cells isolated from the bone marrow microenvironment and cultured on feeder layers of CSF-1, DBP-MAF, or DBP-MAF/CSF-1 for colony enumeration. The increase in macrophage numbers at the expense of neutrophil numbers could be seen in both the in vivo and in vitro experiments. The macrophage/osteoclast and neutrophil lineages have a common precursor, the granulocyte/macrophage colony-forming cell (GM-CFC). With the addition of CSF-1, the GM-CFC precursor may be induced into the macrophage/osteoclast lineage rather than the granulocyte lineage. This increased pool of cells in the macrophage/osteoclast lineage can be functionally upregulated with the subsequent addition of DBP-MAF to perform the activities of phagocytosis and bone resorption. The in vitro data also showed that DBP-MAF did not support colony development as in CSF-1 or the combination treatment. The recruitment and activation of cells into the macrophage/ osteoclast lineage may help to correct the bone and immune defects found in diseases demonstrating a significant lack of myeloid cells, as well as neutrophilia disorders and the disease, osteopetrosis.  相似文献   
93.
Results are presented of a follow-up study in which a representative sample of 608 Prague women aged 20–49 years in 1987 at first interview was re-interviewed in 1992 3 years after the revolution that ended the 41 years of the Communist era in Czechoslovakia. The average yearly consumption of alcohol in the followed-up female sample increased between 1987–92 from a reported 3.6 litres to 4.8 litres. The percentage of heavier drinkers (with average daily consumption of over 20 g alcohol) increased from 7.2% to 14.0%. The women expressed increased tolerance of drunkenness in their attitudes to drinking. The consumption increase was mainly due to increased drinking frequency of spirits and to increased quantity of beer consumed per occasion. The consumption increase was largest in women working as free-lance and the newly emerging self-employed women; economically inactive women did not increase their consumption. Women who reported a positive impact of the socio-political changes on their personal lives and an expansion of social contacts also reported larger than average consumption increases. A coincidence of stressful, possibly self-inflicted, life events and increased alcohol use was observed and interpreted as probably a two-way influence.  相似文献   
94.
目的 分析疏附县炭疽流行病学特征,为制订炭疽防控策略提供依据和参考.方法 对疏附县2005-2012年网络报告的炭疽发病资料进行描述性流行病学分析.结果 2005-2012年疏附县共报告炭疽137例,占同期全国病例总数的5.09%,年平均发病率为5.34/10万.病例全部为皮肤型炭疽,多为散发;夏秋两季高发,7月为高峰月份;男女性别比为1.36∶1,男性发病率高于女性.超过54%的病例为20岁以下儿童和青年,10-14岁高发.病例职业多为农牧民和学生,民族以维吾尔族为主(99.27%).结论 疏附县炭疽发病率极高且呈低龄化特点,应采取针对性措施进一步加强其预防控制.  相似文献   
95.
The authors compared low-dose (32% of standard exposure) storage phosphor digital imaging (system resolution: 0.2-mm pixels, 10 bits) with isovoltage 75-kVp conventional radiography (standard exposure) in the detection of subtle simulated gastric abnormalities by using air contrast barium studies. Subtle simulated abnormalities (3-7-mm polyps, 4-15-mm ulcer craters, 4-11-mm-diameter edema, and 11-12-mm linear ulcers) were produced in resected canine stomachs. Receiver operating characteristic analysis of 1,800 observations by six readers indicated that the digital images with and without high-frequency edge enhancement were equivalent to conventional radiographs (mean receiver operating characteristic areas [+/- standard deviation]: 0.76 +/- 0.06, 0.78 +/- 0.04, and 0.77 +/- 0.04, respectively). The accuracy of the diagnosis was equivalent for all three modalities. The following mean accuracies of negative and positive responses, respectively, for unenhanced digital, edge-enhanced digital, and conventional images were determined: 0.71 +/- 0.05 and 0.41 +/- 0.07, 0.71 +/- 0.04 and 0.51 +/- 0.09, and 0.68 +/- 0.04 and 0.43 +/- 0.05. It was concluded that low-dose storage phosphor air-contrast barium studies were equivalent to conventional radiography in the detection of subtle gastric abnormalities.  相似文献   
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目的 探讨髓核内注射转化生长因子-β1(transforming growth factor-β1,TGF-β1)对预防椎间失稳后软骨终板退行性变的作用.方法 选用6月龄日本大耳白兔36只,随机分为对照组和预防组,每组18只.所有实验动物均制作为腰5-6、腰6-7椎间失稳模型.对照组不予任何处理.预防组在完成椎间失稳手术后立即于同一切口通过侧后方入路显露腰5~6、腰6-7椎间盘,并行髓核内注射TGF-β1.于术后3、6个月各取8只进行HE染色及Mankin评分.结果 术后3、6个月预防组较对照组软骨终板退行性变明显减缓(P<0.05,P<0.01).结论 髓核内注射TGF-β1对椎间失稳后软骨终板退行性变具有明显的预防作用.  相似文献   
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