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1.
2.
Christine D Pollard Susan M Sigward Susumu Ota Karen Langford Christopher M Powers 《Clinical journal of sport medicine》2006,16(3):223-227
OBJECTIVE: To examine the influence of in-season injury prevention training on hip and knee kinematics during a landing task. DESIGN: Longitudinal pre-post intervention study. SETTING: Testing sessions were conducted in a biomechanics research laboratory. PARTICIPANTS: Eighteen female soccer players between the ages of 14 and 17 participated in this study. All subjects were healthy with no current complaints of lower extremity injury. INTERVENTIONS: Testing sessions were conducted prior to and following a season of soccer practice combined with injury prevention training. MAIN OUTCOME MEASUREMENTS: During each testing session three-dimensional kinematics were collected while each subject performed a drop landing task. Peak hip and knee joint angles were measured during the early deceleration phase of landing and compared between pre- and post-training using paired t-tests. RESULTS: Following a season of soccer practice combined with injury prevention training, females demonstrated significantly less hip internal rotation (7.1 degrees vs. 1.9 degrees; P = 0.01) and significantly greater hip abduction (-4.9 degrees vs. -7.7 degrees; P = 0.02). No differences in knee valgus or knee flexion angles were found post-season. CONCLUSIONS: Female soccer players exhibited significant changes in hip kinematics during a landing task following in-season injury prevention training. Our results support the premise that a season of soccer practice combined with injury prevention training is effective in altering lower extremity motions that may play a role in predisposing females to ACL injury. 相似文献
3.
Edda TÖPFER-PETERSEN Johanna AUERBECK Angelika WEISS A.E. FRIESS and W.-B. SCHILL 《Andrologia》1986,18(3):237-251
An antiserum to the purified porcine outer acrosomal membrane (OAM) was raised in female Balb/c mice and was characterized by means of an indirect ELISA. The hyperimmune serum reacted selectively with the acrosomal cap of the sperm head and showed an extremely good cross reactivity with bull and human spermatozoa when assayed by indirect immunofluorescence. Immunoelectron microscopy using the protein A-gold method further confirmed the specificity of the anti-OAM-antiserum for the OAM. In an effort to identify the OAM antigens recognized by the hyperimmune serum and to analyse the extent of cross reactivity on a molecular level, the SDS-extractable proteins were separated by SDS-PAGE, transblotted and immunoprinted using an 125J-conjugated anti-mouse-antibody. To facilitate functional and structural analysis of distinct OAM-proteins monoclonal antibodies were generated by hybridization of mouse myeloma cells with the splenocytes of female Balb/c mice immunized with the purified OAM. One fusion resulted in about 100 anti-OAM-antibodies secreting hybridoma cultures, of which about 30% showed cross reaction with human and bull spermatozoa. Four stable cell lines were selected for this study secreting antibodies directed against the outer acrosomal membrane of boar spermatozoa. Whereas the polyclonal immune mouse serum stained the entire acrosomal cap, the four hybridoma antibodies generated a patch-work-like immunofluorescence pattern over the acrosome. HPLC-ELISA of the solubilized OAM revealed first information on the nature of the corresponding membrane antigen. 相似文献
4.
We have shown earlier that nicotinic agonists induce the release of noradrenaline from chick sympathetic neurons in culture in two ways: (a) by activating the postsynaptic nicotinic receptors on nerve cell bodies, giving rise to spreading electrical activity and opening of voltage operated calcium channels in neuronal processes; (b) by activating the presynaptic nicotinic receptors on neuronal processes. In the present work, we investigated the contribution of various pathways to the observed Ca2+ influx and subsequent noradrenaline release. Sympathetic neurons in culture were stimulated either by the nicotinic agonist dimethylphenylpiperazinium or electrically, in the presence or absence of tetrodotoxin and of specific blockers of calcium or nicotinic channels, and the effects on [Ca2+]i in the area of neuronal processes and on noradrenaline release were measured. Under control conditions, the N-type channel blocker ω-conotoxin (0.1 μmol/1) diminished the release of noradrenaline and the increase of intraterminal Ca2+ by 48% and 55%, respectively, whereas the L-type channel blocker (+)Bay k 8644 (1 μmol/1) diminished the release of noradrenaline by 25% and the increase of [Ca2+]i by 39%. The P-type channel blocker ω-agatoxin (0.3 μmol/1) had no effect. The effects of the L-type channel ligands were complex and could only be explained on the assumption that, at high concentrations, these drugs also act as nicotinic antagonists. Tetrodotoxin blocked the Ca2+ response evoked by electrical stimulation whereas DMPP applied in the presence of tetrodotoxin still evoked an increase of [Ca2+]i and the release of noradrenaline (27% and 30% of control without tetrodotoxin, respectively). These residual responses were not blocked by any of the calcium channel blockers used or by their combination. Apparently, a substantial part of the influx of Ca2+ induced by the activation of presynaptic nicotinic receptors is not carried by the N-, L- or P-type channels and probably occurs directly via the open channels of nicotinic receptors. 相似文献
5.
Angelika Heese Ulrike Lacher Hans Uwe Koch Janna Kubosch Yasmin Ghane Klaus-Peter Peters 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1996,47(11):817-824
Zusammenfassung
Die Typ I-Allergien gegen Latex sind in den vergangenen Jahren zu einem zunehmenden berufsdermatologischen Problem geworden,
zumal mindestens 10% der Angestellten im Gesundheitswesen betroffen sind. In der Dermatologischen Klinik der Universit?t Erlangen-Nürnberg
stieg die Anzahl der j?hrlich diagnostizierten Patienten mit Latexallergien von 1989 bis 1995 auf das 12fache, wobei der Anteil
der schweren, generalisierten Formen der Erkrankung von 10,7% (1989/1990) auf 44% (1994/1995) zunahm.
Unter den m?glichen Ausl?sern der Latexallergie (wasserl?sliche Proteine mit Molekulargewichten von 2 bis 200 kD) sind mindestens
5 Hauptproteine mit bereits bekannter Prim?rstruktur zu berücksichtigen. Zus?tzlich gibt es Hinweise für Markerproteine, die
in bestimmten Risikogruppen geh?uft zur Ausl?sung spezifischer IgE-Antik?rper führen (z.B. 46 kD-Protein in medizinischen
Berufen, 14,6 kD- und 27 kD-Proteine bei Kindern mit Spina bifida). Das Vorkommen von Kreuzreaktionen zwischen Latex und unterschiedlichen
Früchten (besonders Avocado, Kiwi, Banane, E?kastanie) bei 60 bis 70% der Latexallergiker ist bei der allergologischen Abkl?rung
und Beratung dieser Patienten zu beachten. Wesentliche Aspekte der Prophylaxe umfassen die konsequente Umstellung medizinischer
Einrichtungen auf ungepuderte Latexhandschuhe mit niedrigem Proteingehalt. Eine Zusammenstellung von OP- und Untersuchungshandschuhen,
welche Angaben über die von uns ermittelten Proteinkonzentrationen (modifizierte Lowry-Methode und Hochdruck-Flüssigkeits-Chromatographie,
HPLC) enth?lt, soll ein Leitfaden bei der Auswahl allergologisch geeigneter Handschuhe sein.
Eingegangen am 10. August 1996 Angenommen am 21. August 1996 相似文献
6.
Dystonia is a common movement disorder which is thought to represent a disease of the basal ganglia. However, the pathogenesis of the idiopathic dystonias, i.e. the neuroanatomic and neurochemical basis, is still a mystery. Research in dystonia is complicated by the existence of various phenotypic and genotypic subtypes of idiopathic dystonia, probably related to heterogeneous dysfunctions.In neurological diseases in which no obvious neuronal degeneration can be found, such as in idiopathic dystonia, the identification of a primary defect is difficult, because of the large number of chemically distinct, but functionally interrelated, neurotransmitter systems in the brain.The variable response to pharmacological agents in patients with idiopathic dystonia supports the notion that the underlying biochemical dysfunctions vary in the subtypes of idiopathic dystonia. Hence, in basic research it is important to clearly define the involved type of dystonia.Animal models of dystonias were described as limited. However, over the last years, there has been considerable progress in the evaluation of animal models for different types of dystonia.Apart from animal models of symptomatic dystonia, genetic animal models with inherited dystonia which occurs in the absence of pathomorphological alterations in brain and spinal cord are described.This review will focus mainly on genetic animal models of different idiopathic dystonias and pathophysiological findings. In particular, in the case of the mutant dystonic (dt) rat, a model of generalized dystonia, and in the case of the genetically dystonic hamster (dtsz), a model of paroxysmal dystonic choreoathetosis has been used, as these show great promise in contributing to the identification of underlying mechanisms in idiopathic dystonias, although even a proper animal model will probably never be equivalent to a human disease.Several pathophysiological findings from animal models are in line with clinical observations in dystonic patients, indicating abnormalities not only in the basal ganglia and thalamic nuclei, but also in the cerebellum and brainstem. Through clinical studies and neurochemical data several similarities were found in the genetic animal models, although the current data indicates different defects in dystonic animals which is consistent with the notion that dystonia is a heterogenous disorder.Different supraspinal dysfunctions appear to lead to manifestation of dystonic movements and postures. In addition to increasing our understanding of the pathophysiology of idiopathic dystonia, animal models may help to improve therapeutic strategies for this movement disorder. 相似文献
7.
8.
The aim of this study was to investigate the allergenic potency of the exotic fruit lychee (Litchi chinensis SONN.). For this purpose the lychee protein extract was separated by ion exchange chromatography and a purified allergen with a molecular weight of 28 kDa was identified by N-terminal sequencing and peptide mass fingerprinting. Both methods determined the lychee allergen as a triose-phosphate isomerase. To this protein 67% of patients showed allergic reactions respectively IgE binding of their sera. Similar enzymes from other plants were also recognized as allergens. 相似文献
9.
10.
Intraobserver and interobserver variation in the sonographic grading of placental maturity. 总被引:4,自引:0,他引:4
OBJECTIVES: The appearance of Grannum Grade III changes in the placenta at around 34-36 weeks is a predictor of adverse perinatal outcome, which may be reduced by reporting to the clinician. This has led to the suggestion that the placental grade should be noted during any third-trimester scan. There are no published data on the reproducibility of sonographic Grannum grading of the placenta; the objective of this study was to evaluate intra- and interobserver variation. METHODS: Fifty-five placental images from normal and complicated pregnancies of several different gestational ages were collected between April and October 2001. Three fetal medicine consultants and three experienced sonographers graded the images as 0, I, II, III or ungradeable. They then regraded the same images, presented in a different order and with different codes, 4-6 weeks later. Observers were blinded to their previous grading and to each others'. Weighted kappa (kappa), with linear weights, was used to look for strength of agreement. RESULTS: There was good agreement between the two observations of each placental image for five observers (kappa = 0.61 to 0.90), and moderate agreement for one observer (kappa = 0.56). However, the kappa-values for comparisons between the 15 pairs of observers ranged from 0.24 to 0.69 with six values below 0.41, indicating only fair agreement. This was confirmed by the overall kappa-value of 0.24 between all six observers. The agreement between the observers for Grade III placenta was poor, with an overall kappa-value of 0.09. CONCLUSIONS: Although intraobserver agreement was generally good, interobserver agreement was only fair for all grades and poor for Grade III placenta. This may be an indication that Grannum grading is not reproducible or it may reflect a need for training in those performing grading. Such variation may limit the effectiveness of reporting Grannum grades in clinical practice. 相似文献