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81.
Fourteen species of Baptisia were compared serologically, using antiserum against B. nuttalliana. By means of both immunoelectrophoretic and double-diffusion techniques, it was possible to disclose 11 distinct arcs plus some weaker arcs, with few reliable (definite and repeatable) differences detected among the species of Baptisia investigated. Since the individual species of Baptisia are often quite distinctive, as judged by other chemical and morphological criteria, the serological data are in this instance conservative and appear to be effective in circumscribing the genus. In contrast, striking interspecific differences in the serological properties of unicellular green algae have been obtained (reported elsewhere) by similar techniques in this laboratory. It is concluded that serological data should be regarded as adjuncts to other systematic knowledge only on the basis of empirical manifestations of their utility. There is no clear justification for regarding serological data as intrinsically either superior or inferior to other systematic criteria.  相似文献   
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Six malo-lactic strains of lactic acid bacteria were isolated from California wines and identified as Lactobacillus delbrueckii, L. buchneri, L. brevis, Leuconostoc citrovorum, and two strains of Pediococcus cerevisiae. Malo-lactic fermentation was induced in separate lots of wine by inoculation of each lot with one of the strains of bacteria. Malo-lactic fermentation had occurred in each inoculated wine within 2 months. The resultant wines were subjected to chemical analysis, including gas chromatographic examination of concentrated extracts of the wines. Only a few differences in composition were found when the malo-lactic wines were compared one with another. The differences that were found were in volatile acidity and in concentrations of acetoin (plus diacetyl) and probably diethyl succinate.  相似文献   
85.
May, Lewis K. (Woman's Medical College of Pennsylvania, Philadelphia), Ralph A. Knight, and H. William Harris. Allescheria boydii and Aspergillus fumigatus skin test antigens. J. Bacteriol. 91:2155-2157. 1966.-Protein and polysaccharide fractions were extracted from culture filtrates of Allescheria boydii and Aspergillus fumigatus by the methods of Seibert and of Heidelberger, and injected intradermally into guinea pigs previously infected with these fungi. The diameter of erythema and induration was determined at 8, 24, and 48 hr. The protein and polysaccharide antigens yielded specific skin reactions in homologously infected guinea pigs. Erythema appeared at 8 hr with both the protein and polysaccharide antigens. At this time, the polysaccharide skin tests showed erythema and a central blanched wheal. A similar wheal was not observed with the protein. The erythema of the polysaccharide reaction began fading at 24 hr, whereas the protein reaction remained unchanged through 48 hr with both antigens. In guinea pigs, the area of erythema was more constant and thus easier to measure than was induration.  相似文献   
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Failure of epididymal spermatozoa from T/t mutant mice, but not from t/t individuals, to fertilize oocytes in vitro was partially overcome by opening a small aperture in the zona pellucida with acidified Tyrode's solution to permit direct access of the spermatozoon to the vitellus. This study provides a model system to evaluate requirements for successful zona drilling in the treatment of human infertility and further insights into the effects of the t complex on sperm fertility.  相似文献   
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Mature soybean cotyledons (Maturity group VII) were cultured on modified MS containing 0–2.5 μM indole-butyric acid (IBA); 0–10 μM 6-benzylaminopurine (BAP) and 0.7% agar. Embryonic axes of explants were removed prior to culture initiation and cultures were incubated at 24°C with 45–50 μE. s−1.M−2 of mixed irradiance with 16 h photoperiod. Shoot proliferation occurred at 0–2.5 μM IBA and 5–10 μM BAP, while in the presence of 2.5 μM IBA alone, only roots developed. Abnormal shoots were produced with 2.5 μM IBA and 5–7.5 μM thidiazuron. Adventitious shoot development started 7–14 d after culture initiation in the region where the embryonic axis was previously attached to the cotyledon and shoots were visible within 28 days. The presence of the embryonic axis inhibited shoot morphogenesis. The shoots were rooted on half strength MS inorganic salts plus vitamins, 2% sucrose, 0.5 μM NAA acid or 2.5–5 μM IBA, or 5–10 μM IAA, and 0.7% agar. Rooted plants were acclimatized under a mist in the greenhouse. This simple, rapid,in vitro adventitious shoot development protocol could be adapted for transformation/regeneration studies in soybean. Trade and company names are used in the publication solely to provide specific information. Mention of a trade or company name does not constitute a warranty or an endorsement by the U.S. Department of Agriculture to the exclusion of other products or organizations not mentioned.  相似文献   
89.
Summary The protein sequences of seven 3-aminoglycoside phosphotransferases falling into the six identified types and three 6-aminoglycoside phosphotransferases were analyzed to give a rooted phylogenetic tree. This tree supports the origin of these groups of enzymes in an ancestor closely related to the actinomycetes, and that horizontal transfer of the resistance genes occurred, possibly via transposons. The implications for genetic engineering of a novel antibiotic are discussed.  相似文献   
90.
Feces from a specimen of Tamandua tetradactyla (Linn.) from Portel, Pará State, north Brazil, contained two different coccidial oocysts; one identified as Eimeria tamanduae Lainson 1968, and the other as a new species, described here as Eimeria corticulata n. sp. Oocysts of E. corticulata are ellipsoidal, 37.4 x 30.4 (31.2-43.7 x 23.7-35.0) microns, shape index (length/width) 1.2 (1.0-1.5). Oocyst wall 2.5-3.7 microns thick and composed of two layers; an outer thick, brown-yellow one with radial striations, and a thin inner smooth one: no visible micropyle. Oocyst residuum a large globule of about 10.7 x 10.3 microns, usually accompanied by a number of smaller attached globules. Sporocysts ellipsoidal, 21.0 x 11.0 (20.0-22.5 x 10.0-12.5) microns, with a conspicuous Stieda body; shape index 1.9 (1.6-2.2). Sporocyst residuum a small number of scattered granules: sporozoites 18.7 x 5.0 microns, with a large posterior refractile body. Eimeria zygodontomyis n. sp. is described in feces from Zygodontomys lasiurus (Lund) from the Serra dos Carajás, Pará. Oocysts ellipsoidal to cylindrical, 16.5 x 12.0 (13.7-18.7 x 11.2-12.3) microns, shape index 1.4 (1.2-1.5). Wall colorless, smooth, single-layered and about 0.6 micron thick: no micropyle. No oocyst residuum, but a polar granule of about 1.8 x 1.0 microns is sometimes present. Sporocysts ellipsoidal, 8.4 x 5.5 (7.5-8.7 x 5.0-6.2) microns, shape index 1.5 (1.4-1.7), with a thin colorless wall and a delicate Stieda body. Sporozoites enclose a compact residuum of about 2.5 x 3.7 microns.  相似文献   
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