76
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Kaplan N, Hudson RR. The use of sample genealogies for studying a selectively neutral m-loci model with recombination. Theor Popul Biol 1985; 28:382-96. [PMID: 4071443 DOI: 10.1016/0040-5809(85)90036-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A selectively neutral m-loci model with recombination is studied. A general method is developed to calculate the variance of the number of segregating sites in samples of arbitrary size and the m-loci homozygosity. The method is based on properties of the genealogy of the sample rather than diffusion approximations. To demonstrate the scope of the method several calculations are presented.
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77
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Kaplan N, Rosenberg E, Jann B, Jann K. Structural studies of the capsular polysaccharide of Acinetobacter calcoaceticus BD4. EUROPEAN JOURNAL OF BIOCHEMISTRY 1985; 152:453-8. [PMID: 4054115 DOI: 10.1111/j.1432-1033.1985.tb09218.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Compositional analysis of the intact and carboxyl-reduced capsular polysaccharide of Acinetobacter calcoaceticus BD4 (PS-4) showed it to consist of L-rhamnose, D-glucose, D-glucuronic and D-mannose in molar ratios of 4:1:1:1. 13C-nuclear magnetic resonance spectroscopy, methylation analysis, oligosaccharide analysis and base-catalyzed beta-elimination were used to elucidate the primary structure. Oligosaccharides were obtained by enzymatic depolymerization with a specific bacteriophage-induced depolymerase and by partial acid hydrolysis. Form the results it is concluded that PS-4 consists of repeating units of the heptasaccharide (Formula: see text). The bacteriophage-induced depolymerase was found to be an endo-beta-D-glucosidase that hydrolyzed the bond beta-D-Glc-(1----3)-L-Rha to generate a heptasaccharide in 40% yield.
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78
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Kaplan N, Darden T, Langley CH. Evolution and extinction of transposable elements in Mendelian populations. Genetics 1985; 109:459-80. [PMID: 2982700 PMCID: PMC1202498 DOI: 10.1093/genetics/109.2.459] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A model of the evolution of a transposable element family in a Mendelian host population is proposed that incorporates heritable phenotypic mutations in the elements. The temporal behavior of the numbers of mutant and wild-type elements is studied, and the expected extinction time of the transposable element family is examined. Our results indicate that, if the mutant can be transposed equally well in the presence of the wild type, then it can be expected to be found in preponderance, whereas elements, such as retroviruses, where the transposing genome and its phenotypic expression are coupled, may be characterized by a low mutant frequency.
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79
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Arnoczky SP, Warren RF, Kaplan N. Meniscal remodeling following partial meniscectomy--an experimental study in the dog. Arthroscopy 1985; 1:247-52. [PMID: 3841639 DOI: 10.1016/s0749-8063(85)80092-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The response of the meniscus to partial meniscectomy (in the avascular zone) was evaluated in 15 dogs. Following surgery 10 of the 15 dogs (67%) demonstrated a remodeling of the cut surface of the meniscus. This process appeared to begin with a fibrin clot which adhered to the meniscectomy surface. The organized clot was then populated by fibrocytes and eventually modulated into a fibrocartilage-like tissue by 12 weeks. The origin of the cells is unknown and may represent a migration of cells from the synovium, a proliferation of meniscal fibrochondrocytes, or both. The remodeling process appears to be associated with the presence of a fibrin clot, presumably from residual hemarthrosis. In those menisci that did not remodel [five of 15 (33%)], the meniscectomy surface remained relatively unchanged with no signs of progressive degeneration.
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80
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Aquadro CF, Kaplan N, Risko KJ. An analysis of the dynamics of mammalian mitochondrial DNA sequence evolution. Mol Biol Evol 1984; 1:423-34. [PMID: 6599974 DOI: 10.1093/oxfordjournals.molbev.a040327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The dynamics of the substitution process for mammalian mitochondrial DNA have been modeled. The temporal behavior of several quantities has been studied and the model's predictions have been compared with estimates obtained from recent mtDNA sequence data for an increasingly divergent series of primates, the mouse and the cow (Anderson et al. 1981, 1982; Bibb et al. 1981; Brown et al. 1982). The results are consistent with the hypothesis that the decrease in the proportion of transitions observed as divergence increases is a consequence of the highly biased substitution process. In addition, the results support the hypothesis that, although a portion of the mtDNA molecule evolves at an extremely rapid rate, a significant portion of the molecule is under strong selective constraints.
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81
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Jokl P, Kaplan N, Stovell P, Keggi K. Non-operative treatment of severe injuries to the medial and anterior cruciate ligaments of the knee. J Bone Joint Surg Am 1984; 66:741-4. [PMID: 6725321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We are reporting the results of conservative treatment of concomitant injuries to the medial collateral and anterior cruciate ligaments of the knee in twenty-eight patients (average age, twenty-eight years), who were followed for an average of three years. Twenty patients had a good or excellent result. Eleven of the fifteen patients who played contact sports and six of the nine who played non-contact sports returned to their preinjury levels of athletic activity. The older and nonathletic individuals had the poorest final results. We concluded that in many individuals with combined injury to the medial collateral and anterior cruciate ligaments, the knee responds well when treated conservatively.
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82
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Kaplan N, Frohlich ED. Controversies in cardiology. Pharmacologic therapy is not indicated in the treatment of mild hypertension. HOSPITAL PRACTICE (OFFICE ED.) 1984; 19:39-40,45-7 passim. [PMID: 6427251 DOI: 10.1080/21548331.1984.11702837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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83
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Maharaj RJ, Humphrey D, Kaplan N, Kadwa H, Blignaut P, Brock-Utne JG, Welsh N. Effects of atracurium on intraocular pressure. Br J Anaesth 1984; 56:459-63. [PMID: 6426493 DOI: 10.1093/bja/56.5.459] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The effects of atracurium on intraocular pressure (IOP) were compared with those of pancuronium in 20 patients less than 45 years-of-age requiring surgery for trauma of one eye. After a standard premedication and the application of topical analgesia to the upper airway, anaesthesia was induced with thiopentone i.v. and the trachea was intubated without the use of neuromuscular blockade. Following 20 min of steady state anaesthesia during which measurements of IOP, arterial pressure, heart rate, FIO2, FE'CO2 and CVP were recorded, one group of patients received atracurium 0.45 mg kg-1 and the other pancuronium 0.1 mg kg-1. The observations were repeated for a further 15 min before surgery commenced. Neither atracurium nor pancuronium produced any change in IOP. Atracurium was associated with greater cardiovascular stability than pancuronium.
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84
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Langley CH, Brookfield JF, Kaplan N. TRANSPOSABLE ELEMENTS IN MENDELIAN POPULATIONS. I. A THEORY. Genetics 1983; 104:457-71. [PMID: 17246142 PMCID: PMC1202088 DOI: 10.1093/genetics/104.3.457] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
ABSTRACT
Transposable elements are DNA sequences, found throughout eukaryotes, that transpose replicatively and cause numerous genetic and developmental effects on their hosts. A model of the evolution of transposable elements in Mendelian populations is proposed. From its analysis, formulas for the mean copy number and frequency spectrum are obtained.
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85
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Kaplan N, Rosenberg E. Exopolysaccharide Distribution of and Bioemulsifier Production by
Acinetobacter calcoaceticus
BD4 and BD413. Appl Environ Microbiol 1982; 44:1335-41. [PMID: 16346151 PMCID: PMC242193 DOI: 10.1128/aem.44.6.1335-1341.1982] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The heavily encapsulated
Acinetobacter calcoaceticus
BD4 and the “miniencapsulated” single-step mutant
A. calcoaceticus
BD413 produced extracellular polysaccharides in addition to the capsular material. The molar ratio of rhamnose to glucose (3:1) in the extracellular BD413 polysaccharide fraction was similar to the composition of the capsular material. In both strains, the increase in capsular polysaccharide was parallel to cell growth and remained constant in stationary phase. The extracellular polysaccharides were detected starting from mid-logarithmic phase and continued to accumulate in the growth medium for 5 to 8 h after the onset of stationary phase. Strain BD413 produced one-fourth the total rhamnose exopolysaccharide per cell that strain BD4 did. Depending on the growth medium, 32 to 63% of the rhamnose polysaccharide produced by strain BD413 was extracellular, whereas in strain BD4 only 7 to 14% was extracellular. In all cases, strain BD413 produced more extracellular rhamnose polysaccharide than strain BD4 did. In glucose medium, strain BD413 also produced approximately 10 times more extracellular emulsifying activity than strain BD4 did. The isolated capsular polysaccharide obtained after shearing of BD4 cells showed no emulsifying activity. Thus, strain BD413 either produces a modified extracellular polysaccharide or excretes an additional substance(s) that is responsible for the emulsifying activity. Emulsions induced by the ammonium sulfate-precipitated BD413 extracellular emulsifier require the presence of magnesium ion and a mixture of an aliphatic and an aromatic hydrocarbon.
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86
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Kaplan N, Risko K. A method for estimating rates of nucleotide substitution using DNA sequence data. Theor Popul Biol 1982; 21:318-28. [PMID: 7123502 DOI: 10.1016/0040-5809(82)90021-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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87
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Margolin BH, Kaplan N, Zeiger E. Statistical analysis of the Ames Salmonella/microsome test. Proc Natl Acad Sci U S A 1981; 78:3779-83. [PMID: 7022455 PMCID: PMC319656 DOI: 10.1073/pnas.78.6.3779] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
A family of statistical models for analysis of Ames Salmonella/microsome test data is constructed that considers mutation and toxicity as competing risks and allows hyper-Poisson variability. These models have a parameter than can be employed as a mutagenic index because it approximates the slope at zero dose of a dose-response curve adjusted for toxicity. A second parameter quantifies plate-to-plate variability and lends itself to the study of factors affecting internal test reproducibility. The detection of aberrant plate counts is also addressed. This methodology is illustrated with data from a Salmonella test.
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88
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Kaplan N, Risko K. An improved method for estimating sequence divergence of DNA using restriction endonuclease mappings. J Mol Evol 1981; 17:156-62. [PMID: 6267309 DOI: 10.1007/bf01733909] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The method proposed by Kaplan and Langley for estimating the extent of sequence divergence between related DNA's using restriction endonuclease maps is modified so that the estimates are easier to compute. In the two-species case, these modifications lead via a maximum likelihood approach to an estimate which is closely related to one recently suggested by Nei and Li (1979) and Gotoh et al. (1979). Simulation studies show that the modified estimates are comparable to those of Kaplan and Langley, providing that there is sufficient homology in the DNA segments of the related species. The M-species case, M greater than or equal to 3, is also discussed.
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89
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Kaplan N, Langley CH. A new estimate of sequence divergence of mitochondrial DNA using restriction endonuclease mappings. J Mol Evol 1979; 13:295-304. [PMID: 117114 DOI: 10.1007/bf01731370] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A new estimate of the sequence divergence of mitochondrial DNA in related species using restriction enzyme maps is constructed. The estimate is derived assuming a simple Posisson-like model for the evolutionary process and is chosen to maximize an expression which is a reasonable approximation to the true likelihood of the restriction map data. Using this estimate, four sets of mitochondrial DNA data are analyzed and discussed.
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90
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Shapiro AP, Benson H, Chobanian AV, Herd JA, Julius S, Kaplan N, Lazarus RS, Ostfeld AM, Syme SL. The role of stress in hypertension. JOURNAL OF HUMAN STRESS 1979; 5:7-26. [PMID: 115914 DOI: 10.1080/0097840x.1979.9935006] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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91
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Athreya KB, Kaplan N. Convergence of the Age Distribution in the One-Dimensional Supercritical Age-Dependent Branching Process. ANN PROBAB 1976. [DOI: 10.1214/aop/1176996179] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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92
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Rahe RH, McHugh W, Kaplan N, Rimon R, Arthur RJ. Serum lactic acid variability in subjects experiencing stressful training. DISEASES OF THE NERVOUS SYSTEM 1972; 33:403-8. [PMID: 4668960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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93
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Kirshner LA, Kaplan N. Conversion as a manifestation of crisis in the life situation: a report on seven cases of ataxia and paralysis of the lower extremities. Compr Psychiatry 1970; 11:260-6. [PMID: 5443143 DOI: 10.1016/0010-440x(70)90172-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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94
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Barel A, Kaplan N, Léonis J. Physical-chemical studies of papaya lysozyme. ARCHIVES INTERNATIONALES DE PHYSIOLOGIE ET DE BIOCHIMIE 1970; 78:158-9. [PMID: 4100864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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95
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Nadel E, Mantel N, Kaplan N, Altschuler H. Individuality in serum lactic dehydrogenase (LDH) activity in aged perons:significance for cancer diagnosis. Ann N Y Acad Sci 1969; 161:581-601. [PMID: 5260059 DOI: 10.1111/j.1749-6632.1969.tb34092.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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96
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Kaplan N, Rudolph AM. Physiologic studies of pulmonary circulation and ductus arteriosus of sheep and goat fetuses. Application of cineangiographic techniques. Invest Radiol 1969; 4:68-82. [PMID: 5776727 DOI: 10.1097/00004424-196904020-00004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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97
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Pietruszko R, Ringold HJ, Kaplan N, Everse J. Antibody studies with the multiple enzymes of horse liver alcohol dehydrogenase. II. Biochem Biophys Res Commun 1968; 33:503-7. [PMID: 5749172 DOI: 10.1016/0006-291x(68)90604-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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98
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Freeman LM, Zelefsky MN, Meng CH, Kaplan N. Career scientists of the health research council of the city of New York. BULLETIN OF THE NEW YORK ACADEMY OF MEDICINE 1968; 44:1153-8. [PMID: 4875588 PMCID: PMC1750253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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99
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Freeman LM, Zelefsky MN, Meng CH, Kaplan N. The relative merits of lung scanning and angiography in the diagnosis of pulmonary embolism. BULLETIN OF THE NEW YORK ACADEMY OF MEDICINE 1968; 44:1159-82. [PMID: 5243849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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100
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Sharkey J, Kaplan N, Newman HR, Elkin M. The role of potassium in ureteral physiology and pharmacology. INVESTIGATIVE UROLOGY 1968; 6:119-24. [PMID: 5675374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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