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71.
The lung is comprised of about 40 different cell types, of which only 15% are type II cells. These are the major, if not the sole, source of synthesis and secretion of lung surfactant. To date a large number of methods have been described for the isolation of pure populations of type II cells using a wide variety of techniques, but most of these have employed differential centrifugation methods and have used adult rodents. The present study reports the isolation of type II cells from fetal rabbit lungs by the immunoglobin G plating method. Pure populations of fetal type II cells in high yield and with good viability were obtained by the procedure for the first time from rabbit fetal tissue.  相似文献   
72.
A comparative study of two techniques for the PCR genotyping of highly polymorphic tandem repeats was carried out by the example of a triplet repeat in the myotonin protein kinase gene. Sequencing denaturing gels were shown to yield more precise results in the analysis of amplification products.  相似文献   
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Structures of the O-specific polysaccharide chains of lipopolysaccharides from Proteus group OX strains (serogroups O1-O3) used as antigens in Weil-Felix test for diagnosis of rickettsiosis, were established. From them, the acid-labile polysaccharide of Proteus vulgaris OX19 (O1) is built up of the following branched pentasaccharide repeating units connected via a phosphate group: [structure in text] where QuiNAc stands for 2-acetamido-2,6-dideoxyglucose (N-acetylquinovosamine). The basis of serospecificity of the Proteus group OX antigens and their cross-reactivity with human anti-rickettsial antibodies is discussed.  相似文献   
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Mating success of large and small flies of Drosophila malerkotliana and D. bipectinata was studied using multiple, male and female choice methods. In multiple choice method the large male mated with large female and small male paired with small female. In female choice method, large male was successful in mating with female irrespective of its size while in male choice method, preferential mating occurred between large male and large female as well as small male and small female. The consequence of such non-random mating in the presence of male rivarly and preferential mating has been discussed.  相似文献   
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The glycoprotein with the molecular weight of 82,500 D (Ag3) was extracted from the native membranes of fatty globules of human milk and was purified by isoelectrofocusing. Polyclonal antisera (PCA) as well as monoclonal antibodies (MoAb)-ICO-21, ICO-22, ICO-26, ICO-29 against this membrane antigen were produced. The localization of the antigen in the human normal and malignant tissues was tested by the immunochemical technique. Apical staining of the Ag3 was in the acinus and duct cells of the normal breast. Weak staining with the antibodies to Ag3 was revealed in the epithelium cells of ovaries, bronchi, kidney tubules and uterine tubes. The far more pronounced staining of the Ag3 with PCA and MCA was observed in the cell cytoplasma both in the primary and metastatic breast and ovarian tumours. The specificity of the MoAb to Ags suggests that they will be useful in the diagnosis of the malignant disease of the breast and ovary.  相似文献   
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