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81.
Margaret Kain Balbach 《American journal of botany》1965,52(4):317-330
A reinvestigation of the 4 American species of Lepidocarpon described from petrifactions and of Illiniocarpon cadyi, also described from petrifactions, shows that they are all conspecific. When they, in turn, are compared with specimens of the British petrifaction L. lomaxi, no significant differences can be demonstrated. The criteria cited as diagnostic for the American petrifaction species of Lepidocarpon were found to fail as bases of discrimination when 400 specimens of Lepidocarpon found in coal balls of Pennsylvanian age were studied. Measurements and observations made of a sample size of 136 of these 400 specimens reveal a degree of variation compatible with that of a single species. All previously described American and British petrifaction taxa fall within (or not significantly beyond) this range of variability of a single species as determined from this sample. Additional evidence concerning the 3-dimensional sporophyll structure of this one species of Lepidocarpon and the configurations obtained by certain planes of section through it have served to demonstrate that Illiniocarpon cadyi is in reality a taxon based on sectioned structures of the sporophyll of this Lepidocarpon species. Under the rules of priority, this species of Lepidocarpon and the following are assigned to Lepidocarpon lomaxi: Illiniocarpon cadyi, Lepidocarpon ioense, L. magnificum (megasporangiate form), L. crenatum and L. palmerensis. On the basis of the morphological evidence, the British petrifaction described as Lepidocarpon wildianum is also equated with L. lomaxi. 相似文献
82.
Relative Stability of Pertussis Vaccine Preserved with Merthiolate, Benzethonium Chloride, or the Parabens 总被引:2,自引:2,他引:0
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When stored at 4 C, or heated at 22 or 35 C followed by storage at 4 C, the potency of pertussis vaccines preserved with Merthiolate was more stable than the potency of vaccines preserved with benzethonium chloride or the parabens (methyl- and propyl-p-hydroxybenzoate). Without preservative, potency was more stable than in the presence of benzethonium chloride or the parabens, but less stable than when Merthiolate was present. The histamine-sensitizing factor of the vaccines likewise decreased with the loss of potency. The deleterious effect of benzethonium chloride and the absence of the stabilizing effect of Merthiolate were contributing factors, if not the sole cause, for the instability of pertussis vaccine in quadruple antigen vaccine (diphtheria and tetanus toxoids and pertussis and poliomyelitis vaccines). 相似文献
83.
Summary When grown with glucose, S. discophorus synthesized large amounts of poly--hydroxybutyrate which accumulated intracellularly as sudanophilic granules. The rate of endogenous oxygen consumption by such cells was markedly increased by Mn++ and even more by Mg++. It has been shown that these inorganic ions stimulate the oxidation of the intracellular poly--hydroxybutyrate.Dedicated by the senior author to Prof. C. B. van Niel on the occasion of his 70th birthday with gratitude for many unforgettable years of association, instruction and stimulation. 相似文献
84.
Margaret M. Clark 《BMJ (Clinical research ed.)》1967,2(5546):247-248
85.
Chromosome pairing was studied in the following hybrids: Hibiscus radiatus-meeusei (tetraploid F1), H. sabdariffa-meeusei (tetraploid F1 and spontaneous allooctoploid F2), and hexaploid H. acetosella-(sabdariffa-meeusei). Genome constitutions of the species adduced from these data are symbolized as follows: H. radiatus and H. acetosella, AABB; H. meeusei, AAXX; H.sabdariffa, XXYY or AAYY. 相似文献
86.
Aerosol Immunization of Guinea Pigs with Fluid Tetanus Toxoid 总被引:1,自引:0,他引:1
Herbert M. Yamashiroya Richard Ehrlich Josephine M. Magis 《Journal of bacteriology》1966,91(2):903-904
87.
One hundred and forty-eight basal cell carcinomas were treated by curettage and electrosurgery. Twenty-six recurrent carcinomas were treated and 24 did not recur during a minimum two-year follow-up. Seventy-two newly diagnosed carcinomas were treated by the same method, and a two-year recurrence-free rate of 97.4% was obtained. About 50 new and recurrent lesions were treated in three patients in whom extensive cutaneous changes from actinic atrophy and previous therapy made the distinction between new and recurrent lesions difficult or impossible. This technique has a particular place in the management of multiple lesions. Patient acceptance is good. Lesions at some sites, e.g. on the nose, where closure of a wound is difficult, are better managed by this method than by surgical excision. Secondary infection is rare and the cosmetic results are excellent. 相似文献
88.
89.
Physical mapping of the von Recklinghausen neurofibromatosis region on chromosome 17 总被引:15,自引:9,他引:6
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Jane W. Fountain Margaret R. Wallace Anne M. Brereton Peter O''''Connell Raymond L. White Donna C. Rich David H. Ledbetter Robin J. Leach R. E. Keith Fournier Anil G. Menon James F. Gusella David Barker Karen Stephens Francis S. Collins 《American journal of human genetics》1989,44(1):58-67
The von Recklinghausen neurofibromatosis (NF1) locus has been linked to chromosome 17, and recent linkage analyses place the gene on the proximal long arm. NF1 probably resides in 17q11.2, since two unrelated NF1 patients have been identified who possess constitutional reciprocal translocations involving 17q11.2 with chromosomes 1 and 22. We have used a somatic-cell hybrid from the t(17;22) individual, along with other hybrid cell lines, to order probes around the NF1 locus. An additional probe, 17L1, has been isolated from a NotI linking library made from flow-sorted chromosome 17 material and has been mapped to a region immediately proximal to the translocation breakpoint. While neither NF1 translocation breakpoint has yet been identified by pulse-field gel analysis, an overlap between two probes, EW206 and EW207, has been detected. Furthermore, we have identified the breakpoint in a non-NF1 translocation, SP-3, on the proximal side of the NF1 locus. This breakpoint has been helpful in creating a 1,000-kb pulsed-field map, which includes the closely linked NF1 probes HHH202 and TH17.19. The combined somatic-cell hybrid and pulsed-field gel analysis we report here favors the probe order D17Z1-HHH202-TH17.19-CRYB1-17L1-NF1- (EW206, EW207, EW203, L581, L946)-(ERBB2, ERBA1). The agreement in probe ordering between linkage analysis and physical mapping is excellent, and the availability of translocation breakpoints in NF1 should now greatly assist the cloning of this locus. 相似文献
90.