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61.
1978年,烟草病毒病在安徽烟区流行,导致凤阳县烟叶总产损失92.3%,引起了普遍震惊。1981—1984年作者对来自16个县、市552个病毒材料,经生物测定、血清反应、电镜观察,初步分离出CMV、TMV、PVY和PVX四种病毒。它们分别约占检测总数的82.79%、4.53%、2.54%和0.36%,其中CMV与长期视为优势种的TMV比值为18.3,除此,尚有约占检测总数9.8%的CMV和TMV、CMV和PVY复合侵染,以及不明类型的毒株。通过对田间烟草以及其他植物花叶病株的实际检测,进一步表明:CMV在烟区分布范围极广、出现频次最多,已形成了复杂的循环侵染系统,成为近期内烟草病毒病持续流行危害的首要毒原。  相似文献   
62.
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects.  相似文献   
63.
Summary We have investigated the effect of endogenous production of tumor necrosis factor (TNF) induced by the combination of recombinant interferon (rIFN) as a primer followed by GLA-60 as a trigger (rIFN/GLA-60) on murine lung metastases caused by B16-BL6 melanoma. In order to examine the therapeutic effect of endogenous TNF on tumor metastasis, the ability of multiple administrations of rIFN/GLA-60 to induce TNF production was also tested. The multiple administrations of rIFN/GLA-60 at intervals of 2 days were effective for the induction of endogenous TNF in mice but continuous multiple administrations of them for 2–4 days were not. In tumor-bearing mice, the production of endogenous TNF by rIFN/GLA-60 was less than that of normal mice, but treatment 3 days after the surgical excision of primary tumors showed the endogenous TNF production to be similar to that in normal mice. In the experimental lung metastasis model, intravenous administration of rIFN followed by intravenous or intranasal administration of GLA-60 showed potent inhibition of lung metastases of B16-BL6 melanoma, whereas the reverse sequence of administration (GLA-60/rIFN) or administration of a mixture of rIFN and GLA-60, which cannot induce the production of TNF, caused no inhibition of lung metastases. These results indicated that the regression of tumor metastases by rIFN/GLA-60 was mediated by the production of endogenous TNF in addition to the direct effects of both immunostimulants. Furthermore, the administration of rIFN and GLA-60 significantly inhibited the tumor metastases in spontaneous lung metastasis model. These results may provide a promising approach for the treatment of cancer metastasis as a result of its ability to induce endogenous TNF.  相似文献   
64.
家兔48只,用乌拉坦(1g/kg)静脉麻醉,三碘季铵酚制动,在人工呼吸下进行实验。静脉注射安定(0.5mg/kg)以及侧脑室注射氟安定(2mg溶于50μl人工脑脊液中)或γ-氨基丁酸(GABA)(300μg溶于50μl人工脑脊液中)都可降低心室内压峰值(PLVP),减少心力环面积(ACFL)和心室内压最大上升速率(dp/dt_(max))。安定和氟安定对PLVP、ACFL和dp/dt_(max)的抑制作用可被预先在侧脑室注射GABA受体拮抗剂印防己毒素(15μg溶于50μl人工脑脊液中)或双侧延髓腹外侧头端区(γVLM)微量注射GABA受体拮抗剂荷包牡丹碱(3μg溶于0.5μl生理盐水)所阻断。而在延髓网状巨细胞核中间部、网状小细胞核、孤束核或面神经核内注射同样剂量的荷包牡丹碱则不能阻断。 这些结果提示:延髓腹侧部GABA受体的激活可抑制心脏功能,安定对心脏功能的抑制作用可能通过激活延髓腹侧区GABA受体而实现。  相似文献   
65.
清香桂碱D和矮陀陀胺碱A,B的结构   总被引:9,自引:0,他引:9  
本文报道从国产清香桂(Sarcococca ruscifolta)和金丝矮陀陀(Pachysandra axillaria)植物中分得的三个胺碱型新甾体生物碱清香桂碱 D 和矮陀陀胺碱 A、B 的化学结构,并首次归属了它们的~(13)C NMR 数据。  相似文献   
66.
李春瑶  李军生  梁倩华  杨继华   《广西植物》1989,9(3):243-246+291
本文从形态学和组织学方面研究了甘蔗幼叶胚性愈伤组织发生及体细胞胚胎的形成过程。甘蔗幼叶片切段培养于含2.4—D1.5mg/1的MS培养基上,4—6天后切段开始形成愈伤组织,约10天后愈伤组织表面出现白色颗粒状结构。将含有白色颗粒状结构的愈伤组织转移至不含激素的培养基中,7—10天后可见有小植株长出。组织学和形态学观察表明,甘蔗离体再生植株是通过体细胞胚胎发生途径。  相似文献   
67.
前文由柑桔枝条在不同低温下、不同冷冻时间的电解质外渗测定,提出胁强(stress)、作用时间与胁变(strain)之间关系的数学模型。在这个模型中共有3个参数:屈服点温度(yield point temperature),胁强敏感度(stress sensitivity)和作用时间敏感度(sensitivity to duration),用以描述植物的抗性。抗性强的植物应表现为屈服点温度较低,胁强敏感度或者时间敏感度较低。为验证此数学模型,本工作以经冷锻炼与未经冷锻炼的盆栽柑桔枝条为材料,作不同温度与时间处理的电解质外渗率的测定,研究了冷锻炼对于上述3个参数的影响。发现胁强敏感度和屈服点温度受冷锻炼影响而下降,时间敏感度未表现明显变化。对于田间柑桔、油桐与毛竹的定期测定,在固定冷冻时间下,得到了类似于盆栽柑桔的结果。入冬时,植物抗冻性提高,3种植物都表现出下列两种变化:1.胁强敏感度的明显下降;2.屈服点温度和/或时间敏感度亦下降。开春时的变化则相反。胁强敏感度的变化与后一种变化有各自的规律,且因植物种类而不同。拐点胁强(stress at inflection point)具有与半致死温度(50%killing point temperature)不同的意义,它的变化是上述两种变化的综合结果。本试验结果表明,冷锻炼对于植物胁强敏感度有明显影响,用本数学模型的3个抗性指标描述  相似文献   
68.
To verify the hypothesis that the induction of a novel, efficient repair mechanism for chromosomal DNA breaks may be involved in the radioadaptive response, the repair kinetics of DNA damage has been studied in cultured Chinese hamster V79 cells with single-cell gel electrophoresis. The cells were adapted by priming exposure with 5 cGy of γ-rays and 4-h incubation at 37°C. There were no indication of any difference in the initial yields of DNA double-strand breaks induced by challenging doses from non-adapted cells and from adapted cells. The rejoining of DNA double-strand breaks was monitored over 120 min after the adapted cells were challenged with 5 or 1.5 Gy, doses at the same level to those used in the cytogenetical adaptive response. The rate of DNA damage repair in adapted cells was higher than that in non-adapted cells, and the residual damage was less in adapted cells than in non-adapted cells. These results indicate that the radioadaptive response may result from the induction of a novel, efficient DNA repair mechanism which leads to less residual damage, but not from the induction of protective functions that reduce the initial DNA damage.  相似文献   
69.
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V) in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described here is a new mutation, and the first identified in Japanese patients with GAA deficiency. Received: 23 May 1995  相似文献   
70.
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