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1.
《Ibis》1930,72(S1):408-410
The B. O. C. Ruwenzori expedition of 1906 brought home a single immature female of this species, obtained in a papyrus swamp near Lake George, and to Ogilvie-Grant's discrimination we owe the recognition of its specific distinction from galactotes , the species it so closely resembles in coloration, and which is certainly carruthersi s nearest ally.  相似文献   

2.
A pair of chimeric twins, T.S. (male) and M.R. (female), were examined. The amounts of 'foreign' blood cells in each twin found on three occasions were compared. The percentages of M.R. cells found in the blood of T.S. in 1977 and in 1982 were similar and about 1/5 of that found in 1970. The amount of T.S.-blood cells found in M.R. was declining slowly from about 31% in 1970 to about 25% in 1982.  相似文献   

3.
Among the widely applied buffered media, the HSAG (hepes-salt-albumin-gelatin) medium at pH 5.75--6.25 was found to be the most favourable for B.K. virus haemagglutinin titration. The optimum temperature was at 4 degrees C. The haemagglutinin was not affected by temperatures up to 37 degrees C, pHs between 5.5 and 9.5, and NaCl concentrations between 0.063 M and 2.56 M. When incubated at 56 degrees C, the haemagglutinin shows a time and pH dependent decline in titre. No significant time dependent titre fall occurred at 56 degrees C if NaCl molarity was varied between 1.31 and 2.56.  相似文献   

4.
13C-n.m.r. study of C hordein.   总被引:2,自引:1,他引:1       下载免费PDF全文
Insoluble xylan was prepared from ground birch (Betula pubescens) pulp by alkali extraction and precipitation with ethanol. The only sugar detected after acid hydrolysis of the preparation was xylose. The insoluble xylan was used as substrate in a nephelometric assay to determine the xylanase (EC 3.2.1.8, 1,4-beta-D-xylan xylanohydrolase and EC 3.2.1.37, 1,4-beta-D-xylan xylohydrolase) activities of Aspergillus and Trichoderma enzymes. The nephelometric method is reliable in evaluating xylanase hydrolysis of insoluble xylan.  相似文献   

5.
Encephalitis is a challenging public health problem in Kern County and in the San Joaquin Valley area. During the last ten years the authors have studied the epidemiology of encephalitides due to arthropod-borne viruses and the methods used in the differential dignosis of these conditions. To incriminate a virus it is necessary to demonstrate a rise in antibody titer in the blood over a period of seven to fourteen days, the first specimen to be taken as soon as possible after onset of symptoms. A variety of tests may be necessary in some cases. Among the patients included in this presentation the greater number of those with encephalitis and also of those with poliomyelitis were under 30 years of age. The age range was five weeks to 49 years. The median annual mortality rate was 4.3 deaths per 100 cases for poliomyelitis and 3.9 for encephalitis. The greatest incidence occurred during the summer months.The clinical manifestations usually observed in encephalitis are described, but it is emphasized that wide variations and even completely atypical clinical phenomena are encountered. Four representative cases are reported and treatment is discussed. Vaccination and vector control are considered as the most promising means of combating the disease.  相似文献   

6.
C Reyns  J Léonis 《Biochimie》1975,57(2):131-138
The catalysis of the hydration of fumarate and deshydration of L - malate by chicken fumarase was measured spectrophotometrically over a range of substrate concentrations from 4 times 10(-3) M to 8 times 10(-5) M for fumarate and from 8 times 10(-2) M to 10(-3) M for L - malate. For the forward and reverse reactions, linear Lineweaver and Burk plots were obtained. The Michaelis constants and the maximum initial velocities for both substrates were determined and the Haldane relation was found to be obeyed. The effect of pH on activity was investigated over a pH range from 5.5 to 9.0 and the data indicate the presence, in the active site, of two ionizable groups, one in the acidic form and one in the basic form. The values of the ionization constants, determined for the enzyme - substrate complexes, agree closely with the ones obtained for the porcine enzyme. The mode of action of twenty-four structural analogs on the initial velocity of the dehydration of L-malate, by chicken fumarase was examined. From these studies, two regions positively charged appear necessary for the effective binding of the carboxylates of the substrates and competitive inhibitors to the active center. Moreover, the data suggest the presence of an additional group, in the catalytic site of chicken fumarase, that stabilizes the carbon-carbon double bond common to fumarate and its structural analogs. Finally, from the comparison of the kinetic properties of the chicken and pig fumarases, it may be concluded that the catalytic mechanism of the homologous enzymes are very similar, if not identical.  相似文献   

7.
《Carbohydrate research》1987,166(1):27-33
Hydrated and anhydrous cyclomaltohexaose, cyclomaltoheptaose, and cyclomalto-octaose (cyclodextrins) have been investigated by the c.p.-d.d.-m.a.s. 13C-n.m.r. technique. The chemical shifts of the signals of C-1 and C-6 provide information about conformation and the results agree fairly well with the earlier scattering data on hydrated systems, but some discrepancies have been found for cyclomaltohexaose. Th conformation of the macro-rings seems to be determined by the hydration water. The unique role of water in forming crystals of cyclomalto-oligosaccharides is demonstrated.  相似文献   

8.
The degradation of cholic acid by Pseudomonas sp. N.C.I.B. 10590.   总被引:5,自引:2,他引:3  
The microbial degradation of cholic acid by Pseudomonas sp. N.C.I.B. 10590 was studied, and two major products were isolated and identified as 7 alpha, 12 beta-dihydroxyandrosta-1,4-diene-3,17-dione and 7 alpha, 12 alpha-dihydroxy-3-oxopregna-1,4-diene-20-carboxylic acid. Four minor products were isolated and evidence is given for the following structures: 7 alpha, 12 alpha-dihydroxyandrosta-1,4-diene-3,17-dione, 12 beta-hydroxyandrosta-1,4,6-triene-3,17-dione, 7 alpha, 12 beta, 17 beta-trihydroxyandrosta-1,4-dien-3-one and 7 alpha, 12 alpha-dihydroxy-3-oxopregn-4-ene-20-carboxylic acid. The significance of the production of the steroid products is discussed, along with the possible enzymic mechanisms responsible for their production.  相似文献   

9.
The reproducibility of a V.A.C. (Vacuum Assisted Closure) instillation system was investigated by means of an in vitro model. The relation between the volume of a delivered solution and its removal from the system was studied in foams of various size. The relationship of instillation time periods and the volume of delivered solution was determined.  相似文献   

10.
《Ibis》1930,72(S1):77-111
The only European and most familiar species * of the whole genus Cisticola , of which, according to ancient designation †, it is the representative type-species. It is also the species with the widest range.  相似文献   

11.
The use of liquid nitrogen for the removal of warts has advantages over electrocautery in certain circumstances. Although the incidence of recurrences after liquid nitrogen is higher than after cautery, it causes considerably less scarring. It is most useful in dealing with peri-ungual and multiple warts. The technique is simple and a supply of liquid nitrogen can be kept on hand in the office at relatively low cost.  相似文献   

12.
The curricula vitae of four candidates for a professorial appointment at Athens University were examined to estimate the actual contribution of each candidate to the papers of which he was a coauthor. A total of 879 research papers by the four candidates were analysed in terms of the number of authors, the sequence of names, and the year of publication. The four authors presented 364, 349, 96, and 70 papers. If an equal contribution of all coauthors is assumed, the actual number of papers (all papers divided by the number of authors), is about 106, 83, 28, and 26, respectively, so that the rank of the four candidates did not change. On the assumption that the contribution was related to the candidate''s position in the order of the coauthors'' names, the numbers of papers were corrected to 84, 95, 26, 33 using one statistical method and to 88, 94, 28, 31 using another. These assumptions may not be valid, however, especially as the last author may be more important than the intermediate ones. It is suggested that the journals require authors to state their specific contribution to a paper, such as original idea, planning, collecting data, writing up, etc.  相似文献   

13.
A significant heterogeneity of the species Zygowilliopsis californica was revealed using RFLP-analysis of the PCR-amplified rDNA fragment spanning the 5.8S rRNA gene and the internal transcribed spacers ITS1 and ITS2. Phylogenetic analysis of the nucleotide sequences of ITS1 and ITS2 rDNA differentiated three varieties: Z. californica var. californica, Z. californica var. dimennae, and Z. californica var. fukushimae. The most variable was the ITS 2 region, where 7-26 nucleotide substitutions were revealed. The varieties formed semisterile hybrids with meiotic segregation of control markers. The limits of the phylogenetic species concept are discussed.  相似文献   

14.
谷勇  陈芳  吴昊 《植物生理学通讯》2010,(10):1055-1060
以版纳省藤的萌蘖芽为试材,从取材、材料的处理、外植体的诱导分化、芽的增殖、生根以及影响试管苗形成几个重要因素等方面探讨了版纳省藤组织培养和快速繁殖的技术和方法,获得了生长素与细胞分裂素对芽的诱导分化及芽的增殖最佳配比浓度。以改良MS为基本培养基,在增殖培养基中添加0.5mg·L-1NAA、0.5mg·L-1KT和0.1mg·L-1BA,产生的有效苗最多;在生根培养基中添加1.5~2.0mg·L-1IBA生长素有利于版纳省藤组培苗生根。  相似文献   

15.
Rabbits were immunized with RS virus components, isolated as described previously. The sera were tested by neutralization, double diffusion and complement-fixation. RS virus components induced low titers of precipitating and complement-fixing antibodies, and failed to stimulate the neutralizing antibodies.  相似文献   

16.
The use of liquid nitrogen for the removal of warts has advantages over electrocautery in certain circumstances. Although the incidence of recurrences after liquid nitrogen is higher than after cautery, it causes considerably less scarring. It is most useful in dealing with peri-ungual and multiple warts.The technique is simple and a supply of liquid nitrogen can be kept on hand in the office at relatively low cost.  相似文献   

17.
None of the monofluorobenzoates serves as sole source of carbon and energy for growth of Acinetobacter calcoaceticus but all can contribute to growth on other substrates. The monofluorobenzoates are oxidised by bacteria pre-induced for benzoate oxidation and can themselves induce the appropriate enzymes. The initial products of oxidation have been separated and identified by gas-liquid chromatography. 2-Flurobenzoate is oxidised to catechol, fluoride and 3-fluorocatechol; 3-fluorobenzoate gives 3- and 4-fluorocatechol; 4-fluorobenzoate gives 4-fluorocatechol. The fluorocatechols appear to be partially oxidised beyond the stage of 3-oxoadipate by suitably pre-induced bacteria.  相似文献   

18.
A significant heterogeneity of the species Zygowilliopsis californica was revealed using RFLP-analysis of the PCR-amplified rDNA fragment spanning the 5.8S rRNA gene and the internal transcribed spacers ITS1 and ITS2. Phylogenetic analysis of the nucleotide sequences of ITS1 and ITS2 rDNA differentiated three varieties: Z. californica var. californica, Z. californica var. dimennae, and Z. californica var. fukushimae. The most variable was the ITS2 region, where 7–26 nucleotide substitutions were revealed. The varieties formed semisterile hybrids with meiotic segregation of control markers. The limits of the phylogenetic species concept are discussed.  相似文献   

19.
A.M.A. Meeting     
The following summary of actions of the House of Delegates at the American Medical Association''s Thirteenth Clinical Meeting, held December 1-4, 1959, in Dallas, is not intended as a detailed report on all actions taken. It has been composited from reports by Mr. Ed Clancy, director of public relations of the California Medical Association, and by Dr. F. J. L. Blasingame, executive vice-president of the American Medical Association.  相似文献   

20.
The synthesis of three collagen model analogs is described: Ac-Ala-Gly-Pro-Ala-Gly-Pro-NHMe, Ac-Ala-Gly-Pro-Ala-Glc-Pro-NHMe, and Ac-Ala-Glc-Pro-Ala-Gly-Pro-NHMe, where Glc stands for glycolic acid. The 1H-n.m.r. properties of these compounds in dimethylsulfoxide-d6 and trifluoroethanol are described. While in DMSO-d6 the compounds are random, in TFE the glycine amide protons seem to be less solvent exposed than the other amide protons. Little difference was found in the behavior of the three compounds.  相似文献   

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