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71.
A case of a two-year-old boy with multiple subcutaneous lesions caused by Basidiobolus haptosporus is presented.The child had also a non-toxic familial goiter and clinical and radiological features of a pulmonary illness. The pulmonary manifestations only disappeared with the treatment with potassium iodide. The authors think that the pulmonary lesions must have arisen by direct spread of the fungus from the subcutaneous lesions of the chest.  相似文献   
72.
Summary A 2-year-old girl had a de novo duplication in the long arm of one chromosome 7 and an increased level of the enzyme -glucuronidase in cultured fibroblasts. The phenotype of the girl partly overlaps those of two presumptive syndromes due to secondary partial trisomies 7q. The ratio of the enzyme activity was 1.43 to the controls, and 1.37 to her parent's values. We could not define the abnormality but suggest two alternatives: either the patient is trisomic for region q112 to q22 or for the region q22 to q34. If the second alternative is correct the locus for -glucuronidase is possibly assigned to band 7q22.  相似文献   
73.
Conclusion These American anthropological studies both reflect and distort our own Romanian-conceptions. Paradoxically, this gives both Romanian and American researchers an opportunity to verify their validity and reliability. The studies are notable for their multiplicity of theoretical approaches to Romanian reality: each author brings in something new by way of interpretation and, at the same time, maintains a dialectical conception as a methodological frame of reference.The authors are certainly conversant with present and future strategies of development in Romania. But their main problem is that they do not always understand the spirit of the latter and consequently fail to interpret contemporary Romanian realities in a deeply humanistic way.And now, some proposals. For a more active dialogue between Romanian and American scientists I suggest a more comprehensive use of the Romanian sources of information, including historical, beletristic, sociological, and political works. With reference to their reflections on history, the American anthropologists could have discussions with Romanian historians, and could use Romanian historical periodization, especially for the contemporary period. For us, the following sequence is basic: the moment of the armed insurrection as the beginning of the popular democratic revolution (August 23, 1944); proclamation of a Peoples' Republic of Romania (December 30, 1947); unification of Social Democratic Party with the Communist Party to form the Romanian Workers Party (Spring 1948); at this time it is possible to speak of a socialist revolution. The analysis of the Americans should take into consideration these important dates in Romanian history and structure their studies accordingly. Sometimes they must pay more attention to the affective connotation of words, especially for a Romanian reader. Such words would be, for example, their use of elite, rather than leaders, bureaucracy rather than administration, pressure rather than social necessities with the consciousness of development, patronclient instead of using interpersonal relations with mutual benefit, etc.I would also urge that substantive discussions between Romanians and Americans begin, built around specific topics of mutual interest, rather than ceremonial meetings which occur when the parties have neither the language skills, data nor social conceptions to interact fruitfully.I suggest to the American researchers that they maintain and strengthen their contacts with Romanian administrators at local, regional and national levels, so that their studies may contribute to our social praxis.Finally, the Americans should always take into account the economic constraints that shape political, juridical, moral, and philosophical phenomena, and try also to grasp more fully the interaction between elements of the superstructure and between superstructure and base in contemporary Romanian socialist society.Above all, along with Professor Cole , I hope that the scientific effort at interpreting Romanian reality, with its lights and shadows, will be used only for reciprocal knowledge and cooperation.Maria Cobianu-Bacanu is Scientific Researcher at the Center for Sociology, Academy of Social and Political Sciences, Bucharest, Romania.
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Effects of Chlorine Concentration on the Structure of Poliovirus   总被引:5,自引:5,他引:0       下载免费PDF全文
Chlorine concentrations below 0.8 mg/liter inactivated poliovirus without causing separation of the viral components. These results indicate that the release of RNA from the capsids is the result, not the cause, of virus inactivation by chlorine.  相似文献   
77.
A two-step enzymatic synthesis of dTDP-L-rhamnose is developed using enzymes from sonicated extracts of cultures of Escherichia coli K12 strains harboring plasmids containing different parts of the rfb gene cluster of Salmonella enterica LT2. The intermediate dTDP-6-deoxy-D-xylo-4-hexulose was isolated after a 1-h reaction, using only dTDP-D-glucose and dTDP-D-glucose 4,6-dehydratase, followed by protein precipitation and desalting by gel chromatography (yield 89%). In a two-step reaction using dTDP-D-glucose and dTDP-D-glucose 4,6-dehydratase in the first step, and with NADPH, dTDP-6-deoxy-D-xylo-4-hexulose 3,5-epimerase and NADPH:dTDP-6-deoxy-L-lyxo-4-hexulose-4-reductase in the second hour of incubation, the dTDP-D-glucose was fully converted to dTDP-L-rhamnose. The hexoses of both products were identified by mass spectroscopy. The molar yield of dTDP-L-rhamnose, after protein precipitation, anion-exchange chromatography and desalting by gel chromatography, was 62%, corresponding to more than 150 mg, starting from 250 mg of dTDP-D-glucose. When stored lyophilysed under nitrogen, these products were found to be stable for several months. Both dTDP-6-deoxy-D-xylo-4-hexulose and dTDP-L-rhamnose have light absorption maxima at 267 nm, with molar absorption coefficients close to that of dTMP. However, the absorption coefficient of dTDP-6-deoxy-D-xylo-4-hexulose at the absorption maximum of 320 nm (specific for sugars containing keto groups) was found to be approximately 20% higher than values presented earlier. Furthermore, an HPLC technique is presented for determining the net activity of dTDP-6-deoxy-D-xylo-4-hexulose 3,5-epimerase and NADPH:dTDP-6-deoxy-L-lyxo-4-hexulose-4-reductase, based on separation of dTDP-6-deoxy-D-xylo-4-hexulose and dTDP-L-rhamnose. The HPLC technique is also suitable for determination of all the nucleotide components involved in the synthesis.  相似文献   
78.
He-T sequences are a complex repetitive family of DNA sequences in Drosophila that are associated with telomeric regions, pericentromeric heterochromatin, and the Y chromosome. A component of the He-T family containing open reading frames (ORFs) is described. These ORF-containing elements within the He-T family are designated T-elements, since hybridization in situ with the polytene salivary gland chromosomes results in detectable signal exclusively at the chromosome tips. One T-element that has been sequenced includes ORFs of 1,428 and 1,614 bp. The ORFs are overlapping but one nucleotide out of frame with respect to each other. The longer ORF contains cysteine-histidine motifs strongly resembling nucleic acid binding domains of gag-like proteins, and the overall organization of the T-element ORFs is reminiscent of LINE elements. The T-elements are transcribed and appear to be conserved in Drosophila species related to D. melanogaster. The results suggest that T-elements may play a role in the structure and/or function of telomeres.by W. Hennig  相似文献   
79.
A new method is proposed for the microtitration of CBPP vaccines by performing eight parallel endpoint two-fold dilutions. When performed on a 96-well plate, it gives a titre with a precision of +/- 0.2 log10. By comparison, the established method, performed in tubes, gives a precision of only +/- 0.6 log10. The adaptation to microtitre plates allows much more economical culture of larger numbers of samples. Statistical analysis permits determination of vial-to-vial homogeneity of a batch and calculation of a titre with a precision of +/- 0.09 log10. The new method may be applied for the titration of mycoplasmas.  相似文献   
80.
Summary It is known that human and animal fibroblasts are able to induce the retraction of a fibrin clot. In the present study the correlation between (i) fibrinclot retractile (FCR) activity, (ii) the number of actin stress-lines in mouse fibroblasts during growth in culture, and (iii) the sensitivity of actin stress-lines to a powerful actin-depolymerizing factor (ADF), present in plasma and serum of humans and laboratory animals was investigated. Fibroblasts at early passages (2–4) were tested for these parameters at various intervals after seeding (24, 96, and 168 h). The number of actin stress-lines was progressively higher, while the sensitivity to ADF action was progressively lower in cells cultured from 24 to 168 h; the FCR capacity was significantly decreased at 168 h. These data suggest that cells containing weakly polymerized and/or stabilized actin are more active than those containing highly polymerized and/or stabilized actin in triggering fibroblast contraction.  相似文献   
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