Showing papers by "Istanbul University published in 1975"
TL;DR: The time intervals from onset to completion of secondary sexual characteristics were comparable to those reported for European girls for pubic and axillary hair development, but relatively longer for the development of the breast.
Abstract: Ages of attainment of successive puberty stages of the breast, public hair and axillary hair and of menarche were established in a cross-sectional study of 1468 Turkish school girls in Istanbul. Th...
81 citations
TL;DR: In lower socioeconomic classes there was a relative delay of onset and attainment of the subsequent stages of secondary sexual characters, and Acne was encountered in a significant proportion of the boys and increased in frequency with age.
Abstract: Ages of onset and attainment of various stages of secondary sexual characters were assessed from cross-sectional data on 1530 city schoolboys in Istanbul, Turkey. The subjects were grouped into fou...
59 citations
23 citations
TL;DR: A rare case of myxoma of soft tissue presenting in a 34-year-old woman is presented and the prognosis is described as "poor" but "stable".
21 citations
TL;DR: In this article, a third order ordinary differential equation for velocity is solved by boundary conditions and it is shown that how it is possible to overcome the difficulties occuring in the determination of the constants in the solution.
Abstract: Uniform flow of an Oldroyd fluid B past a porous flat plate is investigated. A third order ordinary differential equation for velocity is solved by the boundary conditions and it is shown that how it is possible to overcome the difficulties occuring in the determination of the constants in the solution. It is found that the velocity depends on the suction parameter, the Deborah number and the ratio of the retardation time to the relaxation time; and it is denoted that how those parameters affect on the velocity profiles. Furthermore, a detailed discussion of boundary conditions is also given.
Es wird die stationare Stromung einer Oldroyd-Flussigkeit B um eine porose ebene Platte untersucht. Eine gewohnliche Differentialgleichung dritter Ordnung fur die Geschwindigkeit mit den Randbedingungen wird gelost, und es wird gezeigt wie es moglich ist, die Schwierigkeiten bei der Bestimmung der Konstanten in der Losung zu uberwinden. Man erhalt, das die Geschwindigkeit von dem Saugparameter, der Deborahzahl und dem Verhaltnis der Verzogerungszeit zur Relaxationszeit abhangt. Weiterhin wird auch eine eingehende Diskussion der Randbedingungen durchgefuhrt.
20 citations
TL;DR: In this paper, the mechanics involved in the development of type-A Portevin-Le Chatelier plastic flow in Al 6061 alloy tensile specimens were investigated using strain differential measurements.
Abstract: The mechanics involved in the development of type-A Portevin-Le Chatelier plastic flow in Al 6061 alloy tensile specimens were investigated using strain differential measurements. Specimens with tapered as well as uniform diameter gage sections were used. In the former the Luders bands tend to move into a negative strain gradient, while in the latter they move into a positive gradient. In both cases plastic instability leads to strain rate fluctuations that grow catastropically into the Luders phenomena. Once formed the bands tend to move under a stress increment that is nearly independent of the strain and only weakly dependent on strain rate. The near constancy of the stress required to drive the bands can account for the increase in Luders strain, Δ∈L, with increasing number of band passages, and the fact that Δ∈L increases as a band moves into a positive strain gradient, while it decreases when it moves into a negative gradient.
10 citations
TL;DR: In both the blood and the intraocular fluid, respiration of high percentages of CO2 brought about a respiratory acidosis characterized by an increase in PCO2 and a drop in pH, in a fashion similar to that caused by carbonic anhydrase inhibitors.
5 citations
5 citations
TL;DR: There is circumstantial experimental evidence that an alternate pathway of complement activation and deposition may be operative in acute glomerulonephritis.
Abstract: The authors studied by immunofluorescent and electron microscopy renal biopsy specimens from 29 patients with various glomerular diseases. Poststreptococcal glomerulonephritis was characterized by the presence of complement (beta1C) in the mesangium and/or on the basement membrane in all cases. Immunoglobulin G (IgG) was also present in less than half of the cases in the same distribution. Electron microscopy, carried out in six cases, revealed no uniform ultrastructural change: minimal subepi helial deposits were observed in three cases, intramembranous deposits were seen in two cases, and the basement membrane was normal in one case. Glomerular abnormalities during the courses of some systemic diseases were similar. Mild renal involvement was characterized by only beta1C deposition. This finding raises the question whether a mechanism other than or in addition to that involving immune complexes is operative in the pathogenesis of acute glomerulonephritis. There is circumstantial experimental evidence that an alternate pathway of complement activation and deposition may be operative in acute glomerulonephritis.
3 citations
TL;DR: In this paper, an approximate theory of scalar scattering by a strip in a dissipative medium is established, which is suitable when the relations 1/Im (k)≪h≪d are satisfied by the width of the strip (2h), the smallest distance between the plane of a strip and the exciting sources (d) and the wave number (k).
Abstract: An approximate theory of the scalar scattering by a strip in a dissipative medium is established. The theory is suitable when the relations 1/Im (k)≪h≪d are satisfied by the width of the strip (2h), the smallest distance between the plane of the strip and the exciting sources (d) and the wave number (k). The expressions valid in the far-field approximation are obtained by simple manipulations. Some illustrative examples concerning the scattering of electromagnetic waves, emitted by Hertzian dipoles, by unidirectionally conducting strips are given.
TL;DR: In this paper, the decay of shock waves in an incompressible isotropic hyperelastic half-space, initially at rest and in a state of homogeneous shear strain, was investigated.
Abstract: The decay of shock waves in an incompressible isotropic hyperelastic half-space, initially at rest and in a state of homogeneous shear strain, has been investigated. The asymptotic decay law for plane shear waves has been obtained.
TL;DR: In this article, the authors describe the separation of alunite from natural alunitic kaolins by applying a selective flocculation procedure, which enables the preparation of kaolin of considerable purity.
Abstract: This work describes the separation of alunite from natural alunitic kaolins by applying a selective flocculation procedure. In order to determine the most efficient separating procedure preliminary experiments were performed with artificial mixtures of alunite and kaolin. The same procedure was then applied to natural alunitic kaolin which enabled the preparation of kaolin of considerable purity.
TL;DR: A 50-year-old man with Usher's syndrome, progressive retinitis pigmentosa, and congenital sensoneural deafness developed polycythemia vera.
TL;DR: A new equivalent circuit for SCR's which contains a fictitious inductance is proposed which is much more accurate and more suitable for digital computations of SCR circuits.
Abstract: In this paper a new equivalent circuit for SCR's is proposed. This new equivalent circuit which contains a fictitious inductance is much more accurate and more suitable for digital computations of SCR circuits. A mathematical model which is derived from the equivalent circuit is used to compute the behavior of the SCR circuit. This circuit contains, in addition to SCR's a nonlinear universal series motor. The state equations of this nonlinear circuit have been derived and solved by the digital computer. The paper contains a flow chart of the algorithm and the computed results are presented.
TL;DR: In this paper, an active RC bandpass network with equal-valued capacitors and resistors is proposed, where the sensitivities with respect to all circuit components are derived, and a block containing a differential voltage-controlled current source and a differential Voltage-controlled voltage source is proposed.
Abstract: An active RC bandpass network that uses d.v.c.c.s./d.v.c.v.s. (a block containing a differential voltage-controlled current source and a differential voltage-controlled voltage source) with equal-valued capacitors and resistors is proposed. The sensitivities with respect to all circuit components are derived.
TL;DR: In this article, a method of evaluating the Laplace transform of the state vector by a simple signal-flow graph of state equations is presented, where coefficients of the numerator and denominator polynomials in Mason's gain formula are obtained from sub-graphs whose transmittances are real numbers.
Abstract: A method of evaluating the Laplace transform of the state vector by a simple signal-flow graph of the state equations is presented. The coefficients of the numerator and denominator polynomials in Mason's gain formula are obtained from sub-graphs whose transmittances are real numbers.