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The steady-state shape of a finger penetrating into a viscous fluid that fills the gap between two closely spaced parallel plates is examined. Boundary conditions that take into account variations in the thickness of the thin film and both transverse curvature (across the gap) and lateral curvature (along the interface edge) are applied at the leading edge of the interface. These interface conditions, derived from local solutions in the vicinity of the interface edge, depend on μUn/T, where μ is the viscosity of the original fluid, Un is the normal velocity of the interface edge, and T is the interfacial tension. They also depend on ε/R, where ε=b/a<1 is the ratio of gap width to cell width and aR is the lateral radius of curvature. The problem is solved by conformally mapping the domain to a circle. By expanding the solution in terms of analytic functions and satisfying the boundary conditions, the shape of the interface edge and finger width λ are determined. The agreement between numerical and experimental results is good and an improvement over previous models. The relaxation of the film thickness is also discussed. [ABSTRACT FROM AUTHOR]

The elastic response of ordered 3D soap froth, in which N layers of cells are confined between two rigid walls, is analyzed. Surface Evolver simulations are used to compute the equilibrium structure, which consists of a layer of Fejes-Toth cells at each wall and N - 2 core layers of Kelvin cells. The reference state corresponds to the plate spacing ho that achieves isotropic stress; and the foam confinement is varied by changing h. The foam is sheared in two orthogonal directions to determine elastic behavior up to the elastic limit or yield strain, which corresponds to the onset of topological transitions. The shear moduli in both directions decrease as N increases and slowly converge to the values of bulk Kelvin foam; the dependence on N is well described by a three-layer model consisting of Fejes-Toth cells and a core of Kelvin cells that deform like bulk foam. The influence of foam confinement on the elastic limit is studied. The topological transitions are compared to those in bulk Kelvin foam.

23 patients with rheumatoid arthritis and high rheumatic factors (mean titres of rheumatic factors 1 : 1 434) within a prospective study on the diagnostic and prognostic significance of the rheumatoid vasculitis which was performed together with the Research Institute for Rheumatism Moscow underwent examinations for the proof of an extraarticular organ manifestation. In correspondence with the data in literature we found rheumatic nodes (70%) as most frequent extraarticular organ manifestation. In 1 patient each a participation of the lungs and a rheumatic exudate of the pleura, respectively, could be diagnosed. In another patient there were references to a vasculitis at the fundus of the eye. In only 2 patients there was a vasculitis of the digital arteries with necroses, in one of them a generalized vasculitis. 5 of the 13 neurologically examined patients showed polyneuropathic symptoms. Of the biochemical findings the C-reactive protein and the blood sedimentation rate showed clear increases and correlations.

For the early recognition of the ankylopoietic spondylarthritis subjective and objective criteria are explained and the importance of X-ray-morphological, cytological, biochemical, immunogenetic and coagulation-physiological investigations are explained. By accentuation of two types of constellation of the course the possibility of an early diagnosis is given still before the appearance of severe irreparable X-ray-morphological changes in about half the cases of disease. Further observations and controls of courses are necessary for the confirmation of evidence.

Increases of the leucine aminopeptidase according to data of literature are regarded as a sensitive parameter of lesions in liver diseases. In patients with active generalised lymphadenitis (viral infections, toxoplasmosis) as a typical enzyme constellation a relatively strong leucine aminopeptidase increase in the serum with missing or relatively slight enzyme deviation of the transaminases could be found. The quotient of the activities of LAP/ALAT was clearly above that of inflammatory liver diseases. In chronic lymphatic leukosis, plasmocytoma and malignant lymphomas the leucine aminopeptidase serum activities were within the normal. Increases of leucine aminopeptidase in lymphotropic infections are probably partly of extrahepatic origin.

The acknowledged role of central-nervous mechanisms in the etiopathogenesis of the essential arterial hypertension led to the use of a psycho-physiologic test method with the aim of the early recognition of stress-induced permanent changes of physiologic functions. We succeed in proving the chosen sensumotoric stress in a group of patients with essential arterial hypertension which at first appears uniform in clinical respect allows a further differentiation. On the basis of the behaviour of defined physiologic and biochemical parameters after physical and sensumotoric stress it is referred to the necessity of a differentiated therapy of the early form of the essential arterial hypertension.

In the accessible literature the influence of beta-blockers on laboratory methods is estimated only little systematically and nearly exclusively on parameters of the glucose and lipometabolism. The influence on several methods in vitro is without relevance to practice. Own examinations showed that in 32 patients with essential hypertension of stage I (after Baumann and Nitschkoff) under therapeutic doses of 50--80 mg propranolol a day in none of the 18 chemical parameters tested after a four weeks' treatment significant deviations relevant to practice appeared in comparison to the parameters before treatment.

100 patients with several clinical and suspicious radiological symptoms of Bechterev's disease (Institute of Rheumatology Moscow) and 100 patients with the clinical symptoms of Bechterev's disease without radiological symptoms of a sacroiliacal arthritis (Medico-Policlinical Institute Leipzig) have been examined within a common research programme since 1976 and analysed concerning the frequency of the complaints as well as of clinical symptoms at the beginning of the disease. The main complaints at the beginning of Bechterev's disease are nocturnal pains in the lumbosacral region, pains in the joints, in which cases 50% of the patients spoke of swellings of the joints. 42% of the patients complained of the feeling of the morning rigidity in the lumbar spinal column and 22% spoke of increased temperatures. In 9--10% of our patients an iritis was diagnosed at the beginning of the disease.

On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis.

During examinations and after a three-month examination period the changes of the parameters of fat metabolism were investigated depending upon stress experience before examinations. Students with a distinct stress experience showed a higher total cholesterol and LDL-cholesterol as well as a higher LDL/HDL-cholesterol quotient within a concrete examination. After the examination period in this group a higher LDL/HDL-cholesterol quotient and a lower HDL-cholesterol level was established in comparison to the group with an insignificant stress experience. A positive dependence on the initial value of the parameters of fat metabolism consists only in the group with distinct stress experience. According to these results also stress has an influence on the reactions of the fractions of cholesterol.

Local instillations of various medicaments with the aim of a so-called chemical synovectomy are compared with the experiment of a possible causal therapy by operative synovectomy. Under this aspect corticosteroids are used still relatively frequently also for the intraarticular treatment. They diminish transiently the inflammation of the pannus, but they do not remove it. On the basis of its good local compatibility in relapsing effusions of the large articulations, mostly of the knee-joints, which appeared in the course of a chronic progressive rheumatoid arthritis of Bechterew's disease, cyclophosphamide was applied intraarticularly and was compared with the results after injections of prednisolone. Apart from the clinical findings cytological and biochemical examinations of the synovial membrane, which more exactly than clinical parameters allow an objective estimation of the local inflammatory activity, were used for the judgement of the success. With the help of intraarticular treatment of cyclophosphamide within a complex chemotherapy an improvement of the findings and a stabilisation of the process can be achieved. Local applications of prednisolone often lead to a rapid, however, in most cases not remaining reduction of the activity at the joint. In uninfluencable high local activity of the process, objectified by examinations of the synovial membrane, an early synovectomy is indicated for the prevention of the formation of irreversible chondropathies.

Activity and results of therapy of joint diseases can be evaluated by means of cytological examinations of the synovia which is at the same time a prerequisite for differential diagnosis using the puncture fluid. Our cytological examinations of more than 700 puncture fluids stemming from different joint diseases were carried out immediately after the puncture on the fresh material, in order to prevent misinterpretation. This may occur through flaking out in stored material, which results in decrease in the cell count and a non-representative differential cell picture in the supernatant, as well as through degeneration of cells. In two thirds of our patients the local process activity, measured in terms of the cytological phase of activity, became evident in the total clinical activity. The synovia analysis furthermore permits objective assessment of the result of intra-articular injection treatment. Intractable activity, substantiated through synovia examination indicates synovectomy.

The synovial milieu in uric arthritis is characterized with the help of own findings of examinations and data in literature. Apart from the mean values of cytological and biochemical findings of the synovia the changes under therapy are described on the basis of individual examples. The formation of monosodium urate crystals seems to be the starting point of the inflammatory joint process in gout. The size of the arthritic syndrome is among others determined by the local metabolic process, in which case lactate acidosis and reduction of energy as well as the increase of enzyme activities seem to stand in the foreground.