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本文描述了发现于福建的冬青科冬青属2新种——泰宁冬青Ilex tainingensis G. S. He和南平冬青I. nanpingensis G. S. He,并分别说明两者与其他近缘种的区别要点。泰宁冬青与太平山冬青I. sugerokii Maxim.的区别在于前种小枝被毛,无棱槽,叶片宽卵圆形,花淡紫色,分核表面具细条纹,背后中部有一凹槽。南平冬青与拟榕叶冬青I. subficoidea S. Y. Hu区别在于前种果为椭圆形,较大,表面光滑无腺点,果梗长于1 cm,每分核上端有2尖角,均可以区别。 相似文献
3.
白纹伊蚊幼虫龄期的发育历期 总被引:2,自引:0,他引:2
在实验室内20±1℃, 23±1℃, 25±1℃, 28±1℃和30±1℃恒温条件下, 观察了白纹伊蚊(Aedes albopictus)幼虫(广州株)的发育历期.幼虫的总发育历期和各龄幼虫的发育历期随温度的上升而缩短, 各龄幼虫历期在总发育历期中占有恒定的百分比, 据此计算出其捕获机率.各龄幼虫的发育历期与温度呈直线回归关系.通过积温公式, 求出各龄幼虫的积温常数.此外还探索了营养对幼虫发育历期的影响, 从而影响各龄幼虫捕获机率的计算. 相似文献
4.
Respiratory burst develops in myeloid blast cells if they differentiate functionally along the monocytic or granulocytic lineage. Using the nitroblue tetrazolium (NBT) assay we studied the effects of recombinant human granulocyte/macrophage colony stimulating factor (rhuGM-CSF), rhuG-CSF and rhuM-CSF on development of respiratory burst activity in primary blast cells from patients with myeloid leukemia. Assessing suspension cultures containing cells from patients with acute myeloid leukemia (AML, n = 13) or myeloid-blast crisis (myBC) of chronic myeloid leukemia (CML, n = 5) it was found that the percentage of NBT positive cells was increased by at least 20% as compared to control cultures by rhuGM-CSF in 6/17 cases, by rhuG-CSF in 7/17 cases and by rhuM-CSF in 0/16 cases, representing in 'responders' a mean increase of 267% and 270% in the absolute number of NBT positive cells by rhuGM-CSF and rhuG-CSF, respectively. Morphological examination of cultured cells from 'responders', as compared to controls, showed decreased blast cell content but generally no evidence of terminal differentiation. The demonstration of Auer rods in NBT positive cells indicates that respiratory burst developed in a leukemic clone. These findings may be of physiological, pathophysiological and clinical relevance. 相似文献
5.
大肠杆菌 O55B5内毒素在体外可抑制人血小板自发性聚集,并使血小板内 cAMP、钙调素明显增高,但对肾上腺素诱发的血小板聚集无作用,也不能引起血小板致密颗粒和α-颗粒的释放。此外还观察到内毒素组无血小板上清液中5-HT 含量减少。 相似文献
6.
在狗的心脏上装入微超声探头和高精度微压力传感器,手术后两星期,在清醒状态下给予左冠状动脉旋支阻断三分钟。在复灌注过程中,观察到血液动力学指标与收缩期心室壁厚度(WT)迅速恢复正常;但在 dWT/dt—WT 环形图上出现舒张早期异常相,其形状与缺血过程不同。低氧和急遽冠状动脉过度充盈可以产生此种异常图形。我们推测,心肌缺血可能促使一些产物的形成,复灌注时它使冠脉过度舒张,冠脉灌注增加,从而造成舒张早期急遽充盈而形成了此种异常的形图。 相似文献
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Recombinant human tumor necrosis factors alpha and beta stimulate fibroblasts to produce hemopoietic growth factors in vitro 总被引:4,自引:0,他引:4
J R Zucali H E Broxmeyer M A Gross C A Dinarello 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(3):840-844
The influences of TNF alpha and TNF beta were evaluated for their stimulatory and inhibitory effects on in vitro colony formation by human bone marrow granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) progenitor cells. Both TNF alpha and TNF beta induced fibroblasts to produce stimulators of CFU-GM, BFU-E, and CFU-GEMM in a dose-dependent fashion. Similar results were seen when equivalent concentrations of TNF alpha and TNF beta were used. Prior incubation of the TNF alpha and TNF beta with their respective antibodies inactivated the ability of the TNF preparations to induce the release of granulocyte-macrophage, erythroid, and multipotential colony-stimulating activity from fibroblasts. In addition, incubation of the TNF-induced fibroblast supernatant with antibody before colony assay resulted in enhanced colony formation, suggesting that the TNF carried over into the colony assay suppressed colony formation. Additional proof of this suppression by TNF was evident when TNF was added directly to the CFU-GM, BFU-E, and CFU-GEMM colony assays. IL-1 does not appear to function as an intermediary in growth factor production by fibroblasts stimulated with TNF because antibody to IL-1 displayed no effect. Furthermore, assay of TNF-induced fibroblast supernatant was negative for IL-1. These results suggest that TNF alpha and TNF beta exert both a positive and negative influence on in vitro hemopoietic colony formation. 相似文献
9.
H E Broxmeyer D E Williams S Cooper G Hangoc P Ralph 《Journal of cellular biochemistry》1988,38(2):127-136
Combinations of low dosages of purified recombinant human (rh) macrophage-colony stimulating factor (M-CSF; also termed CSF-1) and rh granulocyte-colony stimulating factor (G-CSF) were compared alone and in combination for their influence on the cycling rates and numbers of bone marrow and splenic granulocyte-macrophage, erythroid, and multipotential progenitor cells in vivo in mice pretreated with iron-saturated human lactoferrin (LF). LF was used to enhance detection of the stimulating effects of exogenously added CSFs. Concentrations of each CSF that were not active in vivo when given alone were active when given together, with the other CSF. The concentrations of rhM-CSF and rhG-CSF needed to increase progenitor cell cycling in the marrow and spleen were reduced by factors of 40-200 when these CSFs were administered in combination with low dosages of the other CSF. At the concentrations of rhM-CSF and rhG-CSF tested, synergism was not noted on absolute numbers of progenitor cells or total nucleated cell counts per organ or circulating in the blood. These findings may have potential relevance when considered in a clinical setting where the CSFs might be used in combination with other biotherapy and/or chemotherapy. 相似文献
10.
实验在α氯醛糖和氨基甲酸乙酯混合麻醉的大鼠中进行。脑室内注射高张盐水(icv.HS)后,肾血浆流量、肾小球滤过率、尿量、尿钠排出量、尿钾排出量和渗透物质清除率均增加,游离水清除率下降。去除垂体后,icv.HS不再能引起上述肾脏反应。另外给大鼠静脉注射血管升压素(VP)拮抗剂(V_1和V_2受体拮抗剂),并不能削弱上述icv.HS引起的肾脏反应。脑室内注射高张盐水后,尿中多巴胺(DA)排出量无显著增多;给予多巴脱羧酶抑制剂苄丝肼也不能削弱icv.HS引起的肾脏反应。上述实验结果表明,在本实验条件下刺激脑内渗透压感受器引起的肾脏反应依赖于垂体的完整性,但看来并不依赖于外周的VP和DA,故垂体通过何种机制介导icv.HS引起上述肾脏反应,有待于进一步的研究。 相似文献