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101.
Dr. A. M. Würfel A. Voigt F. Linke S. Hofmann von Kap-herr 《European journal of trauma and emergency surgery》1995,21(2):70-76
From 1984 to 1992 153 children were treated at the pediatric surgical department of the University of Mainz, of whom 19 had fractures of the radius, 9 of the ulna and 125 had a combination of both in the diaphysis of the forearm. Factors like patient's age, type of fracture and therapeutic methods were analyzed. One hundred and forty-one children were treated conservatively, 12 by operation. One hundred and one of these patients were healthy, when discharged (about 8 weeks after accident). Follow-up was possible in 69 cases. We found that occasional a remaining dislocation angle does not impair function: in 65 cases the result was “good” and “very good”, but only “moderate” in 4 cases. These 4 children had been treated conservatively by reposition and plaster cast; 2 of these 4 children showed bone reconstruction without dislocation. Twenty-two of the 56 X-ray follow-up's showed persisting dislocation. To prevent functional problems (2 of our cases) it is essential to obtain a very exact reposition of diaphyseal forearm fractures. Therefore we would recommand a more generous indication for operation, preferably using elastic-stable Nancy pins. 相似文献
102.
G Heimke D Stock C M Büsing D von Mallinckrodt 《Journal of biomedical materials research》1989,23(7):679-684
Uncemented total hip replacements have resulted in a higher incidence of postoperative complaints than cemented ones. The theoretical explanation of these not well defined discomforts is based on the differences of the stress and strain fields around the distal portions of the femoral components. While the noncemented stems are press-fitted and most of them tapered distally, thus creating hoop stresses and strains in the surrounding cortical bone, the shrinkage of the cement prevents these mechanical irritations. The relatively sudden disappearance of these discomforts within the first 2 postoperative years is attributed to the shift of the main zone of load transmission from the distal to the proximal portion of the stems following bone remodeling. 相似文献
103.
Immunohistological analysis of lymphocyte subpopulations infiltrating breast carcinomas and benign lesions 总被引:1,自引:0,他引:1
S von Kleist J Berling W Bohle C Wittekind 《International journal of cancer. Journal international du cancer》1987,40(1):18-23
We characterized different subpopulations of infiltrating mononuclear cells using 8 monoclonal antibodies (MAbs) on serial cryosections of breast tissue from 85 cancer patients and 32 samples of benign lesions, and the ABC technique. In general, lymphocytes were found more frequently and more abundantly in cancerous lesions. The infiltrates consisted mainly of T-cells in close contact with malignant cell-nests. T-helper/inducer cells clearly predominated over T-suppressor/cytotoxic cells in neoplastic tissues, whereas in benign tissues the T-helper/suppressor ratios seemed to be well balanced. While a few MAb Leu-7 (HNK-I)-reactive NK cells were found in the stroma of the breast tumors, none could be identified in the noncancerous lesions. The correlation of these data with histology and tumor stage of patients has been evaluated by a quantitative approach using planimetry in an interactive registration system. 相似文献
104.
In 16 healthy volunteers, 16 patients with neurogenic pain syndromes, 37 patients with idiopathic pain syndromes, and 30 depressed patients, melatonin in serum was determined at 2 a.m. when the peak concentration was expected. In a somewhat larger series comprising 53 healthy volunteers, 14 patients with neurogenic pain syndromes, and 35 patients with idiopathic pain syndromes, melatonin was measured in urine collected during the night in a standardized manner. Chronic pain patients (with neurogenic or idiopathic pain disorders) and depressed patients had significantly lower melatonin in serum at 2 a.m. than healthy volunteers. Chronic pain patients also had significantly lower melatonin in urine than healthy volunteers, even when age, sex, and body weight were taken into account. The low melatonin concentrations were related to increased depressive symptomatology, especially sadness, bodily discomfort, inner tension, concentration difficulties, and pain. As low concentrations of melatonin in serum and urine also are found in patients with depressive disorders, the results are in line with the suggestion that the chronic idiopathic pain syndrome may be a variant of depressive disease, or the two syndromes may share a common pathogenic mechanism. 相似文献
105.
E. A. von Reth M. J. F. P. Pluym A. A. van Steenhoven J. Poulis A. Versprille 《Medical & biological engineering & computing》1987,25(1):51-56
The indicator-dilution technique is commonly used to determine mean flow estimates. The estimation of instantaneous flow from
the shape of an indicator-dilution curve is the objective of this study. Based on a mixing chamber approach to the flow system,
a mathematical relationship is derived to reconstruct momentary flow from an indicator-dilution curve. This relationship is
verified in a model setup both with only constant flow and with a sinusoidal flow variation superimposed. This method proved
to give good flow estimates for limited values of flow parameters. Also, some preliminary experiments were performed in a
pulsating flow system simulating heart action. The results were promising although the method proved to be very sensitive
to baseline offset. 相似文献
106.
A silicone implant for surgery of refractory glaucomas has been developed. It consists of a tube 0.64 mm in diameter glued to the upper surface of a plate resembling a contact lens. The surgical procedure, which is similar to a trabeculectomy, is described. 相似文献
107.
C Sch?fl K S Cuthbertson C A Walsh C Mayne P Cobbold A von zur Mühlen R D Hesch J A Gallagher 《Journal of bone and mineral research》1992,7(5):485-491
ATP released from damaged cells or by controlled secretion could be an important factor in the formation or remodeling of bone. In a variety of other tissues ATP has been shown to control cellular processes by acting on P2-purinoceptors and activating the calcium signaling pathway. Here we demonstrate for the first time that extracellular ATP increases the intracellular free calcium [Ca2+]i concentration in normal human osteoblasts and in SaOS-2 cells, a human osteosarcoma-derived cell line, but not in ROS 17/2.8 cells. The ATP-induced increase in [Ca2+]i was dose dependent, and the concentrations of ATP required were similar to those reported to regulate cellular functions in other cell types. Although ATP is metabolized rapidly by bone cells, the effects on [Ca2+]i appeared to be mediated directly by ATP rather than one of its metabolites. Adenosine 3-thiotriphosphate, a nonhydrolyzable analog of ATP, induced similar changes in [Ca2+]i. This indicates that P2-purinoceptors are present on osteoblast-like cells and that extracellular ATP from various sources might be an important factor in the regulation of osteoblast functions. 相似文献
108.
Neuropathy with lysosomal changes in Marinesco-Sj?gren syndrome: fine structural findings in skeletal muscle and conjunctiva. 总被引:1,自引:0,他引:1
The light- and electron-microscopical findings in the skeletal muscle and conjunctiva of 6 patients with Marinesco-Sj?gren syndrome (MSS) were presented. All patients were related and showed the cardinal clinical symptoms of the syndrome: congenital cataracts, mental retardation, delayed statomotor development, and cerebellar ataxia. The most prominent alteration found in the skeletal muscle of four patients was extensive neurogenic atrophy with conspicuous groups of atrophic muscle fibers. Additional findings were vacuolar degeneration and secondary, unspecific changes like slight mitochondrial alterations and increased variability in muscle fiber calibers. The ultrastructural examination revealed double-membrane structures near to, but not in direct contact with the nucleus. The nuclear changes described earlier (7, 20) were not found in any of the cases. Conjunctival biopsies revealed a marked increase in the number of lysosomes in fibroblasts. In summary, to the well known myopathic damage of muscles in MSS a neurogenic component should be added. Disturbed lysosomal function is to be considered as the basic abnormality, though the enzyme defect has not yet been identified. In cases of clinically suspected MSS, examination of a conjunctival biopsy is highly recommended. 相似文献
109.
110.
BERND-DIETER GONSKA KEJIANG CAO ANSELM SCHAUMANN AXEL DORSZEWSKI FRIEDERIKE von zur MÜHLEN HEINRICH KREUZER 《Pacing and clinical electrophysiology : PACE》1994,17(3):542-549
The management of patients after catheter ablation of ventricular tachycardia is not well defined. In this article we summarize recently published results and report our own experience. Factors influencing the clinical outcome of these patients and methods to identify patients with an increased risk of recurrence of ventricular tachycardia are discussed. Furthermore, a review is given on current concomitant therapeutic tools including antiarrhythmic drugs and the implantation of an automatic cardioverter defibrillator. 相似文献