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1.
Iron deficiency may exacerbate symptoms in the Restless Legs Syndrome (RLS). We investigated the effect of intravenous iron sucrose or placebo on symptoms in patients with RLS and mild to moderate iron deficit. Sixty patients with primary RLS (seven males, age 46 (9) years, S‐ferritin ≤45 μg/L) recruited from a cohort of 231 patients were randomly assigned in a 12‐months double‐blind, multi‐centre study of iron sucrose 1000 mg (n = 29) or saline (n = 31). The primary efficacy variable was the RLS severity scale (IRLS) score at week 11. Median IRLS score decreased from 24 to 7 (week 11) after iron sucrose and from 26 to 17 after placebo (P = 0.123, N.S. for between treatment comparison). The corresponding scores at week 7 were 12 and 20 in the two groups (P = 0.017). Drop out rate because of lack of efficacy at 12 months was 19/31 after placebo and 5/29 patients after iron sucrose (Kaplan–Meier estimate, log rank test P = 0.0006) suggesting an iron induced superior long term RLS symptom control. Iron sucrose was well tolerated. This study showed a lack of superiority of iron sucrose at 11 weeks but found evidence that iron sucrose reduced RLS symptoms both in the acute phase (7 weeks) and during long‐term follow up in patients with variable degree of iron deficiency. Further studies on target patient groups, dosing and dosing intervals are warranted before iron sucrose could be considered for treatment of iron deficient patients with RLS. © 2009 Movement Disorder Society  相似文献   
2.
We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline.  相似文献   
3.
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC.  相似文献   
4.
Summary Biotinylated neoglycoproteins are useful to determine the expression of sugar receptors (lectins) histochemically in routinely processed tissue sections. Assessment of the presence of distinct receptor classes with specificity to-galactosides and to- or-N-acetylgalactosamine, selected on the basis of their potential relevance for recognition processes within the metastatic cascade in murine model systems, was performed for a common human tumour type, colorectal cancer. The four different types of neoglycoproteins, derived from covalent attachment of commercially available derivatives of-N-acetylgalactosamine, differed only quantitatively in their capacity to detect specific binding on cultured cells and tissue sections, thus posing no major restriction on the choice of synthetic process for histochemical efficiency of the product. Glycocytological application revealed specific probe binding and a regulation of level of receptor expression for a human colon carcinoma cell line primarily forN-acetylgalactosamine-specific receptors upon retinoic acid-induced differentiation. Monitoring of sections of the 12 cases of primary and secondary colorectal lesions invariably disclosed the presence of the respective receptors, the extent of cell labelling in primary tumours and metastases being similar. Establishment of metastases, even in different target organs, is apparently not followed by a major phenotypic variation in this feature.  相似文献   
5.
Bioreactions at the tissue/hydroxyapatite interface   总被引:2,自引:0,他引:2  
The events at the hydroxyapatite implant material/tissue interface in the rat middle ear were studied by light microscopy, autoradiography, morphometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray microanalysis. Deposition of calcium, partially in the form of calcium phosphate, was found at the interface. Resorption of the implant material occurred as the result of mono- and multinuclear phagocyte activity. Resorption decreased 6 mnth after the operation, possibly due to the decreasing number of phagocytes at the interface and the increasing amount of bone in the macropores.  相似文献   
6.
The biocompatibility of two silicone rubbers, Silastic and Dow Corning Elastomer, and of a polyether and a polyester urethane, a polyether polyester copolymer, and polypropylene oxide was assessed in vitro. These elastomers were selected for assessment as a possible alloplastic tympanic membrane. For these studies use was made of rat middle ear mucosa explants and serially cultured epithelium. The quantitative results were based on epithelial growth curves, the morphological picture was based on the findings in epithelium, and the aging of a biomaterial was simulated. Epithelium morphology was investigated by scanning and transmission electron microscopy and x-ray microanalysis. Quantitative results showed that on Dow Corning Elastomer and polypropylene oxide, cell proliferation was significantly lower compared to normal growth curves. The morphological findings were negative for polypropylene oxide, and did not discriminate between the other biomaterials under study. The simulation results indicated better biocompatibility for the polyurethanes and the polyether polyester copolymer compared with that of polypropylene oxide and both silicone rubbers. Under the simulation conditions, cells exposed to Silastic showed silicon-containing inclusions. These in vitro results suggest that the biocompatibility of the polyurethanes and the polyether polyester copolymer is better than that of both silicone rubbers and polypropylene oxide.  相似文献   
7.
Zusammenfassung Mikrokallusformationen lassen sich in nahezu allen Skelettabschnitten der Spongiosa nachweisen. Mikrokallus besteht aus Geflechtknochen, der sich an lokal überbelasteten Stellen in der Spongiosa bildet. Mit Hilfe einer speziellen Pr?parationstechnik wurden 26 skelettgesunde und 11 Wirbels?ulen von F?llen mit Osteoporose untersucht. Mikrokallusformationen finden sich bevorzugt bei Frauen ?lter als 45 Jahre in den unteren Wirbels?ulenabschnitten. Dabei hat die Mikroarchitektur der Spongiosa (TBPf) einen st?rkeren Einflu? auf die Anzahl der Mikrokalli, als individuelle Trabekelparameter (Tb.N, BV/TV und Tb.Th). Nur in 33 % der Formationen lassen sich Frakturspalten nachweisen. Mikrokallusformationen k?nnen nichtinvasive Knochenmassemessungen verf?lschen. Auch wenn Mikrokallusformationen Indikatoren für eine Instabilit?t der Spongiosa sind, tragen sie zur Knochenregeneration bei, und die Entstehung neuer Trabekel ist durch sie m?glich. Die Vorstellung, da? Osteoporose das Resultat einer verminderten Mikrokallusbildung ist, trifft nicht zu.   相似文献   
8.
The biocompatibility of porous implants made of Estane 5714 F1 polyether urethane, polypropylene oxide, and a poly(ethylene oxide hydantoin) and poly(tetramethylene terephthalate) segmented polyether polyester copolymer (HPOE/PBT copolymer), which were selected as candidates for an alloplastic tympanic membrane, was assessed after implantation in rat middle ears for periods of up to 1 year. Implantation of the materials led to tissue reactions initially associated with the wound-healing process, whereas after 1 month not only the presence of macrophages and foreign-body giant cells surrounding the implant materials but also implant degradation were characteristic for a foreign-body reaction. Macrophages and foreign-body giant cells dominated the picture of the tissue surrounding polypropylene oxide. The altered morphology of these cells, the persistent infiltration of the implantation sites by exudate cells, and the premature death of five rats in the 1-year group suggest that polypropylene oxide degradation was accompanied by the release of toxic substances. Estane and copolymer degradation did not induce tissue responses reflecting implant toxicity, and tympanic membranes given these alloplasts showed a normal healing pattern. Inclusions in the cytoplasm of macrophages associated with degradation and phagocytosis of all of the polymers under study were found to contain iron, silicon, titanium, and aluminum. Growth of fibrous tissue and bone, the latter into Estane and HPOE/PBT copolymer implants, indicated appropriate implant fixation by tissue, although macrophages and foreign-body giant cells were present as well. Especially the fixation of copolymer by ingrowth of bone seems promising in terms of the amount of bone in the pores and the electron-dense bone/copolymer interface. The latter is indicative for bonding osteogenesis. The HPOE/PBT copolymer is a better candidate for alloplastic tympanic membrane than Estane, and the use of polypropylene oxide cannot be recommended.  相似文献   
9.
We describe a patient initially diagnosed with a chronic myeloproliferative disorder in the accelerated phase. Cytogenetic analysis showed the presence of two independent clones. One clone contained a typical Philadelphia (Ph) chromosome due to t(9;22)(q34;q11), as the sole abnormality which was proven molecularly to result in the b2a2-BCR/ABL fusion. The other clone displayed a complex karyotype with several structural and numerical aberrations including trisomy 11 and 22 but lacking a t(9;22) or any other structural abnormalities involving chromosomes 9 and 22. Fluorescence in situ hybridization demonstrated that the t(9;22) was present only in cells with two copies of chromosomes 11 and 22. In contrast, cells with trisomies 11 and 22 lacked evidence for a BCR/ABL fusion. Based on the genetic findings, simultaneous chronic and acute myelocytic leukemias were diagnosed rather than a blastic phase of a chronic myelocytic leukemia.  相似文献   
10.
Serum from an atopic patient undergoing a hyposensitization therapy to birch pollen allergens was used to carry out immunocytochemical mapping of specific IgE/IgG binding sites within ultrathin sections of birch pollen grains. There was a distinct rise in the density of specific IgG labelling in the course of therapy, whereas the density of IgE labelling remained fairly constant. However, the patterns of IgG and IgE binding in the pollen grain did not completely coincide since there was only IgE binding to certain pollen structures such as the apertural region. If the widely accepted concept of specific antibodies as 'blocking antibodies' is taken as a basis, the success of therapy must be questioned in this case because no IgG antibodies were formed to some of the allergens localized in the pollen grain and relevant to this patient. Very probably this result must be attributed to an incomplete pollen extract used in hyposensitization therapy. The results of the biochemical measurements (RAST, ELISA) agreed well with the immunocytochemical observations.  相似文献   
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