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31.
32.
本属与多种树种有菌根关系:如Pinus,Larix,Abies和Pseudotsuga,但在Larix林下,本菌往往与土壤中的鞣料相聚集,对周围某些植物根系不利。本属现知15种,本区6种。 相似文献
33.
The technical feasibility of adopting the fixed-film reactor concept for biogas production from screened dairy manure was investigated. The methane production capability of laboratory-scale 4-L anaerobic reactors (conventional and fixed-film) receiving screened dairy manure and operated at 35 degrees C was compared. Dairy manure filtrate with 4.4% total solids (TS) and 3.4% volatile solids (VS) (average value) was prepared from 1:1 manure-water slurry. The feed material was added intermittently at loading rates ranging from 2.34 to 25 and 2.25 to 785 g VS/L d, respectively, for the conventional and fixed-film reactors. Maximum methane production rate (L CH(4)/L d) for the conventional reactor was 0.63 L CH(4)/L d achieved at a 6-day hydraulic retention time (HRT). For the fixed-film reactor the maximum production rate was 3.53 L CH(4)/L d when operated at a loading rate of 262 g VS/L d (3 h HRT). The fixed-film reactor was capable of sustaining a loading of 785 g VS/L d (1 h HRT). The fixed-film reactor performed much better than the conventional reactors. These results indicate that a large reduction of required reactor volume is possible through application of a fixed-film concept combined with a liquid-solid separation pretreatment of dairy manure. 相似文献
34.
1983年4月至1984年5月,对新疆伊犁哈萨克自治州五个民族的近亲结婚情况进行了调查。调查的婚姻数为维吾尔2553起,哈萨克1079起,回1235起,锡伯1222起,蒙古446起。近亲结婚率与平均近交系数分别为:维吾尔——8.23%与 46.74×10~(-4),回——8.10%与45.07×10~(-4),锡伯——4.66%与24.93×10~(-4),哈萨克——2.87%与11.31×10~(-4)。蒙古——0.45%与 2.80×10~(-4)。解放以来,维吾尔族与回族的近亲结婚率有上升趋势,而锡伯族的则有下降趋势。各族近亲结婚中大部分为亲表亲结婚,但堂亲结婚在维吾尔族的近亲结婚中竟占26.18%,在回族中也占16.00%。1303名近亲结婚子女中的七岁前死亡率(12.89%)及先天性缺陷与遗传性疾病发生率(2.99%)显著高于6370名非近亲结婚子女的相应值(7.65%及0.38%)。 相似文献
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边缘性缺乏抗坏血酸之豚鼠,于三周内其肝脏及小肠粘膜3-羟-3-甲基戊二酰辅酶A还原酶(HMGR)活力均下降到原有水平的50%,但肝脏胆固醇7α-羟化酶活力尚无显著性改变。坏血病豚鼠(三周内)上述几种酶活力都下降至原有水平的50%左右。豚鼠摄取抗坏血酸不足,其血清总胆固醇浓度显著增加,而血清高密度脂蛋自胆固醇浓度显著减少,其改变程度与抗坏血酸缺乏状况一致。 相似文献
37.
本文报道了一种快速、灵敏的血小板释放功能检测方法:利用荧光素-荧光素酶在有ATP、Mg~(2+)、O_2存在时产生的生物发光素测定血小板ATP的释放量,以反映血小板的释放功能;研究了ADP、AA、胶原、凝血酶等四种诱导剂对血小板释放功能的作用,发现ADP的诱导释放能力较其他三者为弱;观察在不同剂量ADP和AA的诱导下,血小板聚集强度和释放能力之间的关系,研究了血小板数等因素对ATP释放功能测定的影响。应用该方法研究了Aspirin及活血化淤药物川芎嗪,毛冬青甲素对血小板释放功能的影响,发现Aspirin对AA诱导的释放反应有强烈的抑制作用。在以ADP诱导的释放反应中,川芎嗪的抑制作用较毛冬青甲素更为强烈。 相似文献
38.
The use of a hydroxylapatite-filter steroid receptor assay method in the study of the modulation of androgen receptor interaction 总被引:2,自引:0,他引:2
Receptors for androgen, estrogen, and glucocorticoid can be assayed by hydroxylapatite adsorption of the radioactive steroid-receptor complex and washing of the adducts on membrane filters mounted on a multiple filter holder. The method is economical, very rapid and sensitive. This new receptor assay method was used to study the modulation of androgen receptor of rat ventral prostate by metal ions, thiols, and ligand structure. The interaction of androgen with the naked receptor is inhibited by 10 microM ZnCl2, CdSO4, or CuSO4 but this inhibition is competed by androgen and is reversed by DTT. The androgen-receptor complex is less sensitive to divalent metal ions but Zn2+, at 3 mM, appears to alter the conformation of the receptor and promote the release of androgen. Certain phenanthrene derivatives exhibited striking structural specificities in their ability to compete with radioactive androgen for binding to the prostate receptor. The results suggest that the receptor has binding preference toward individual ring structure in the steroid. 相似文献
39.
40.
A rabbit antiserum against bovine pancreatic DNase A is used to study the immunological reaction of DNases I. As shown by double immunodiffusion, bovine pancreatic DNases A, B, C, and D are immunologically identical, so are DNases from bovine pancreas and parotid and from ovine pancreas. These DNases also behave similarly in immunotitration of DNase activity and all are tightly bound to the immunoaffinity medium, requiring an acidic buffer with 10% ammonium sulfate to dissociate. On the other hand, porcine pancreatic and malted barley DNases that do not form precipitin lines remain active in solution with the antibody; however, in spite of the lack of inhibition these DNases are retarded (but not tightly bound) in immunoaffinity chromatography, suggesting interaction with the antibody. In thin layer isoelectric focusing, the parotid DNase, purified with the immunoaffinity technique, shows only two major active components whose isoelectric points correspond to those of DNases A and C of bovine pancreas. As estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the molecular weight of parotid DNase is 34,000, approximately 3,000 more than that of the pancreatic enzyme. However, both parotid and pancreatic DNases have the same NH2-terminal leucine, an identical COOH-terminal amino acid sequence, nearly identical amino acid compositions, and almost the same peptide maps. The molecular weight difference is due to differences in the carbohydrate side chains. Results of peptide analyses indicate that parotid DNase contains two glycopeptides; pancreatic DNase has only one. In addition, both parotid glycopeptides contain glucosamine and galactosamine while the pancreatic glycopeptide has only glucosamine. 相似文献