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91.
嗜热脂肪芽孢杆菌是一个尚未被严格定义的种,它几乎包括芽孢杆菌属内所有能在65℃以上生长的细菌。用聚丙烯酰胺凝胶电泳的方法对151株嗜热脂肪芽孢杆菌的9种酶(G6PDH、LDH、MDH、IDH、AlaDH、LeuDH、过氧化氢酶、过氧化物酶、酯酶)的酶谱进行测定分析。根据其酶谱的差异,可将151株菌株分成两个类型。两型之间8个酶的13或14个基因产物的相异度约为91.8%,两型间的标准遗传距离是2.55。因此这两种类型的细菌也许可以被看作为两个不同的种。  相似文献   
92.
Sixty depressed patients and 52 normal controls completed three selfreport inventories: the Symptom Checklist-90 (SCL-90), the Beck Depression Inventory (BDI) and a new Verbal Style Investigation Schedule (VESIS) developed by the first author. The VESIS uses 16 key emotional and physical terms from Western inventories and identified the words and phrases most commonly used by Chinese patients to express these feeling states. Chinese subjects commonly used the key term itself for only 3 or the 16 key terms; they usually preferred to use other words or phrases to express the feeling state. We categorized these Chinese expressions into four styles of verbal expression: Psychological, Somatic, Neutral (i.e., a mixture of psychological and somatic) and Deficient (i.e., lack of expression because of denial or suppression). Three of the 12 key emotional terms of the VESIS (depressed, fearful, and anxiousness) were more commonly expressed in a somatic or neutral mode than the other key emotional terms. The key terms suicidal interest and being punished were more commonly expressed in a deficient style than other key emotional terms. The somatic factor score of the SCL-90 was not correlated with increased somatic expression of emotional states; thus patients who have multiple somatic complaints are not more likely to express emotions somatically. The hypothesis of somatization is discussed in light of this study.  相似文献   
93.
从疏花毛萼香茶菜叶的乙醚提取物中一共分得七个二萜化合物,其中四个经各项光谱数据证明它们分别为毛萼乙素(1),毛萼晶甲(2),毛萼晶乙(3)和冬凌草素(4)。  相似文献   
94.
七种云南地衣植物的化学成分   总被引:13,自引:1,他引:12  
本文报道分属于三个科的七种云南产地衣植物的化学成分。这些植物是亚洲树发(Alectoria asiatica DR.)、沟树发(Alectoria sulcata Nyl.)、长茎松萝(Usnea longissimaAch.)、胡子松萝(Usnea comosa(Ach.)Rohl.)、林石蕊(Cladonia arbuscula(Rabh.)Rabh.)、砖孢发(Oropogon loxensis(Fee.)Th.Fr.)和卷梢雪花衣(Anaptychiaboryi(Fee.)Mass.)。根据光谱数据测定,其化学成分为:松萝酸(Usnic acid)(1),维任西酸(Virensic acid)(2),赤星衣酸乙酯(Ethyl haematommate)(3),瑞藏酸(Rhizonic acid)(4),赤星衣酸(Haematommic acid)(5),扁枝衣酸乙酯(Ethyleverninate)(6),黑茶渍素(Atranorin)(7)和泽屋萜(Zeorin)(8)。上述资料,对开发利用这些植物资源提供了科学依据。  相似文献   
95.
96.
宁夏同心中新世铲齿象化石   总被引:8,自引:6,他引:2  
本文记述了宁夏同心地区中中新世哺乳动物群中铲齿象化石——同心铲齿象 (Platybelodon tongxinensis) (原定为同心嵌齿象 (Gomphotherium tongxinensis). 通过与国内外已现的有关铲齿象对比,确认其与国内已发现的葛氏种关系最近,可能属同一枝系.同心种与葛氏种相比,是性质相对原始分布层位较低的我国第二个铲齿象种.文章初步讨论了其 M_3 的某些变异性状.并结合现有的其它标本初步阐述了铲齿象类下门齿的两种结构类型,原始型的同心层状结构和衍生型的齿质柱状结构.建议根据这两种结构仍将铲齿象类划分为 Platybelodontinae 和 Amebelodontinae.  相似文献   
97.
Although acute alterations in Ca2+ fluxes may mediate the skeletal responses to certain humoral agents, the processes subserving those fluxes are not well understood. We have sought evidence for Ca2+-dependent ATPase activity in isolated osteoblast-like cells maintained in primary culture. Two Ca2+-dependent ATPase components were found in a plasma membrane fraction: a high affinity component (half-saturation constant for Ca2+ of 280 nM, Vmax of 13.5 nmol/mg per min) and a low affinity component, which was in reality a divalent cation ATPase, since Mg2+ could replace Ca2+ without loss of activity. The high affinity component exhibited a pH optimum of 7.2 and required Mg2+ for full activity. It was unaffected by potassium or sodium chloride, ouabain or sodium azide, but was inhibited by lanthanum and by the calmodulin antagonist trifluoperazine. This component was prevalent in a subcellular fraction which was also enriched in 5′-nucleotidase and adenylate cyclase activities, suggesting the plasma membrane as its principal location. Osteosarcoma cells, known to resemble osteoblasts in their biological characteristics and responses to bone-seeking hormones, contained similar ATPase activities. Inclusion of purified calmodulin in the assay system caused small non-reproducible increases in the Ca2+-dependent ATPase activity of EGTA-washed membranes. Marked, consistent calmodulin stimulation was demonstrated in membranes exposed previously to trifluoperazine and then washed in trifluoperazine-free buffer. These results indicate the presence of a high affinity, calmodulin-sensitive Ca2+-dependent ATPase in osteoblast-like bone cells. As one determinant of Ca2+ fluxes in bone cells, this enzyme may participate in the hormonal regulation of bone cell function.  相似文献   
98.
MICROSPECTROPHOTOMETRIC ANALYSIS OF NUCLEAR DNA IN CHARA ZEYLANICA   总被引:1,自引:1,他引:0       下载免费PDF全文
Microspectrophotometric analysis of the DNA content of nuclei in various parts of Chara zeylanica Willd. revealed that the amount of DNA in the nucleus of an internodal cell equals twice the amount of DNA in the nucleus of a sperm, while the half-anaphase stage of the same nodal cells contains the same amount of DNA as the nuclei of the male gametes. The DNA content of the nuclei of internodal cells may rise as much as 50 times higher than that of the gametes. However, in the oldest (most basal) internodal cells, the DNA content of the minute nuclei falls again to the basic (1 C) amount. Measurements of sister nuclei derived by amitosis indicated that both nuclei have equal amounts of DNA; this was interpreted as further evidence that amitosis is not a disorganized process or manifestation of degeneration. The bearing of these analyses on the question of the site of meiosis in these plants is discussed.  相似文献   
99.
Summary A study of the behaviour of the photosynthetic products assimilated at different growth stages was conducted in the field and in the greenhouse using C14 tracer.In general, the assimilated carbon is translocated to and accumulates in the growing organs. The carbon assimilated at the maximum tiller number stage is distributed mostly to the lower leaves. The carbon assimilated at the booting stage is distributed mostly to the spikelet, certain leaf sheaths and culms. The carbon accumulated in the form of carbohydrates in the leaf sheaths and the culm before flowering is retranslocated to the panicle after flowering. However, because of the consumption by respiration, the efficiency of this type of carbohydrate in grain production is not very high. The carbon assimilated after flowering accumulated mostly and efficiently in the brown rice.The release of the assimilated carbon as CO2 is most intense immediately after assimilation. Thirty-five to 60 per cent of the assimilated carbon is consumed through respiration under the conditions of this experiment. As the carbon, which is in the form of sugars, rapidly changes to other forms, and also is consumed by respiration, the consumption declines rapidly. The retention percentage of assimilated carbon decreases as mutual shading increases.The large proportion of carbon released through respiration indicates the importance of studies on the significance of respiration in relation to growth.A portion of the thesis for the Master of Science degree submitted by Mr. Shen Lian to the Graduate School, University of the Philippines, College of Agriculture.  相似文献   
100.
用末端转移酶催化生物素核苷酸底物(Biotin-ll-dUTP)共价连接在合成的寡核苷酸3’羟基末端,从而合成了两种寡核苷酸探针(β~T_(41-42)及β~A_(41-42))。用它们分别与克隆化扩增的正常和突变的β—珠蛋白基因片段杂变。结果表明该探针都具有与~(32)P探针相似的特异性,其杂交的灵敏度为2—3pg(特异序列)。进而将探测HbS基因的正常和异常两种寡核苷酸19聚体(β~A_6和β~S_6)用~(32)P和生物素分别标记;将HbS杂合子病人的白细胞DNA经聚合酶链反应(PCR)法扩增,并以含正常β—珠蛋白基因的DNA片段作对照,与两种探针分别进行斑点杂交。所得结果完全一致;Hbs杂合子DNA对正常和异常探针都显出杂交信号,而正常DNA只与β~A探针显杂交信号。  相似文献   
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