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121.

Purpose

To evaluate acute toxicity and efficacy of simultaneous radiochemotherapy for invasive urothelial cancer of the bladder.

Patients and Methods

From September 1993 to July 1997,61 patients with invasive bladder cancer were treated with a transurethral resection (TURB) followed by radiochemotherapy (RCT). Twenty-five received a combination of 5-FU and cisplatin. The prescribed doses were 600 mg/m2 5-FU daily as continuous infusion over 5 days each in the 1st and 5th treatment week and 20 mg/m2 cisplatin daily at the same days as a short infusion. The pelvis was irradiated with 54 Gy, the bladder with 59.4 Gy and the paraortic nodes in 7 cases with 45 Gy, respectively. Six to 8 weeks after RCT a second TURB was performed for reasons of restaging.

Results

Twenty out of 25 patients received at least 80% of the prescribed chemotherapy, in 13 cases the full dose could be given. Gastrointestinal toxicity of Grade I and II occurred in 10 cases, 1 patient developed severe diarrhea (Grade VI). After the 1st course of chemotherapy 7 patients had leucoor thrombopenia of Grade III. One patient had a leucopenia of Grade IV. After the 2nd course 4 patients developed Grade III leuko- and thrombopenia, 1 of Grade IV. Two Grade II anemia were found. All more severe toxicities and necessary dose reductions were related to radiation of the paraaortic nodes. No life threatening infections, bleedings or cardiotoxicity was found. Restaging TURBs resulted in 22 complete remissions, 1 patient had a de-novo-carcinoma (Tis) at this time, 2 were non-responders (8%). After a median follow-up of 38 months 20 patients are alive (80%).

Conclusions

1. If irradiation of paraaortic nodes is necessary, 5-FU should not be applied, because the gastrointestinal toxicity is too extensive. In all other cases side effects are tolerable and can be managed by supportive care. 2. The first results are promising and should be evaluated in a prospective study.  相似文献   
122.
Summary The dissociation constant for actin binding to myosin and its subfragments (S1 & HMM) is 1 m at physiological ionic strength. Many of the methods used to measure such affinities are unreliable for a Kd below 0.1 m. We show here that the use of phalloidin to stablise F-actin and fluorescently labelled proteins allows the affinity of actin for myosin S1 to be measured in a simple transient kinetic assay. The method can be used for Kd's as low as 10 nm and we demonstrate that the Kd's can be estimated using only g quantities of material. Furthermore we suggest how this method may be adapted for ng quantities of protein. This will allow the affinity of actin for myosin fragments to be estimated for proteins which are difficult to obtain in large quantities i.e. from biopsy material or from proteins expressed in baculovirus.  相似文献   
123.
Intraocular silicone lenses in silicone oil: an experimental study   总被引:4,自引:0,他引:4  
Background: To evaluate a potential effect of silicone oil on flexible silicone intraocular lenses, four lenses (STAAR AA-4203) were stored in silicone oil under sterile conditions for periods between 1 month and 3 years. Method: The edge and surface of the lenses were examined by scanning electron micrography and the findings compared with a lens of the same model which had been stored in Ringer's solution for 2 years. Results: After 1 year of silicone oil exposure, droplets of different sizes adherent to the surface of the lens were found. These changes proceeded to a wave-like appearance of the surface after 2 and 3 years of storage, so that a continuous layer of silicone oil polymers is probably covering the intraocular lens. Conclusion: Optical interference has to be considered a possibility if it turns out that the droplets cannot be removed during silicone oil evacuation. Consequently silicone intraocular lenses without hydrophilic preparation of the surface should not be implanted in eyes undergoing combined anterior and posterior segment surgery with silicone oil tamponade or in eyes with high risk for vitreoretinal complications.The authors state that they have no proprietary interest in the marketing of the products mentioned herein or competing products  相似文献   
124.
Summary We present a 2-year survey of bacteraemic episodes due to -haemolytic streptococci and a case of recurring infection due to group C streptococcus,Streptococcus equisimilis. We found 53 episodes of bacteraemia with -haemolytic streptococci. Group A was the most common, followed by groups B, G and C. The proportion of nosocomial cases was the same in all four groups i. e. 24% (neonatal cases excluded). The clinical picture presented by groups C and G streptococcal cases was indistinguishable from that caused by group A streptococci, but patients with group G bacteraemia were older than patients with group A bacteraemia. Obvious clinical foci were more common in group A than group G cases. Disregarding neonatal cases, most patients had predisposing conditions. There was no difference in foci of bacteraemia, predisposing factors, treatment and outcome of disease. The overall mortality was 25%.
Bakteriämie durch -hämolysierende Streptokokken: Zweijahresübersicht und Vorstellung eines Falles von rezidivierender Infektion durch Streptococcus equisimilis
Zusammenfassung Wir geben eine 2-Jahres-Übersicht über bakteriämische Episoden durch -hämolysierende Streptokokken und stellen einen Fall von rezidivierenden Infektionen durch Streptokokken der Gruppe C,Streptococcus equisimilis, vor. Wir fanden 53 Episoden von Bakteriämie durch -hämolysierende Streptokokken. Gruppe A war am häufigsten vertreten, es folgten die Gruppen B, G und C. Der Anteil nosokomialer Infektionen war in allen vier Gruppen gleich, das heißt 24% (Neugeborene ausgeschlossen). Das klinische Bild der durch Streptokokken der Gruppen C und G verursachten Infektionen war von den durch A Streptokokken verursachten nicht zu unterscheiden, doch waren Patienten, die durch Streptokokken der Gruppe G infiziert wurden, älter als Patienten mit Bakteriämie durch Streptokokken der Gruppe A. Bei Streptokokken der Gruppe A ließen sich häufiger eindeutige klinische Infektionsherde identifizieren als bei der Gruppe G. Abgesehen von den neonatalen Fällen hatten die meisten Patienten disponierende Faktoren. Hinsichtlich der Bakteriämieherde, disponierenden Faktoren, Behandlung und Krankheitsverlauf fanden sich keine Unterschiede. Die Gesamtsterblichkeit lag bei 25%.
  相似文献   
125.
Nitric oxide (NO) is a short-lived diffusable molecule now believed to participate in multiple physiologic functions in the CNS including neurotransmission and the maintenance of vascular tone. Previously, we reported that cell lines obtained by retroviral immortalization of tissue macrophages (M?;) could be induced to synthesize nitrite (NO), a stable end product of the NO synthetic pathway. We have further characterized the induction and activity of this pathway in a panel of seven microglial clones derived from primary embryonic mouse brain cultures. Like M?;, these clones were found to release high levels of NO-2 in response to recombinant interferon-γ (rIFN-γ) as a priming signal together with either bacterial lipopolysaccharide (LPS) or exogenous recombinant tumor necrosis factor-α (rTNF-α). As previously demonstrated for M?;, phagocytosis of zymosan particles during induction of enzyme activity enhanced subsequent NO production, which is of interest in light of the postulated phagocytic role of microglia within the CNS. Biochemical characterization of enzyme activity in intact microglial clones and in isolated cytosolic fractions indicates that the microglial NO synthase present in these murine cell clones represents the M?;-like isotype. These findings suggest that microglial cells could represent a major source of NO within the CNS.  相似文献   
126.
Zusammenfassung In einer Interview-Studie von 480 Betagten in städtischen Verhältnissen wurden neben anderen Fragen auch solche zur Zufriedenheit gestellt. Eine Faktoranalyse der Antworten erlaubt die Unterscheidung eines Faktors Depressivität von einem Faktor Zufriedenheit mit Sozial-kontakten und einer gesundheitlichen Dimension.
Dimensions of satisfaction among old people
Summary In an interview study of 480 aged persons, questions on satisfaction with several aspects of life were included. A factor analysis allows to distinguish a factor relating to depressivity from a factor satisfaction with social contacts and a health-related dimension.

Dimensions de la satisfaction des personnes âgées
Résumé Das une enquête d'un échantillon de 480 personnes âgées, des questions concernant leur satisfaction ont été inclues dans l'interview. Une analyse factorielle permet de distinguer un facteur associé à la dépressivité d'un facteur satisfaction avec les contactes sociaux et d'une dimension santé.
  相似文献   
127.
Summary Chromatographic analysis of 3,5-cyclic nucleotide phosphodiesterase (PDE) isoenzymes in the cytosol of human neutrophils shows the predominant presence of PDE IV (cAMP specific) and PDE V (cGMP specific). PDE IV is characterized by (1) cAMP selectivity, (2) a KM for cAMP of 1.2 M and (3) a typical rank order of IC 50-values for PDE inhibitors: 0.13, 0.17, 47 and 9.5 M for PDE IV selective rolipram, PDE III/IV selective zardaverine, PDE III selective motapizone and unselective 3-isobutyl-l-methylxanthine (IBMX), respectively. Functions of polymorphonuclear leukocytes (PMN) such as N-formylmethionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide release and fMLP/thimerosal elicited leukotriene (LT) biosynthesis are inhibited by these PDE inhibitors with the same rank order and even lower IC50-values. Measurements of changes in cytosolic Cai in Fura-2 loaded PMN demonstrate a transient Cai increase after stimulation with 0.1 M fMLP and an additional sustained elevation of Cai levels in the presence of thimerosal. PDE inhibitors suppress this sustained phase of Cai release with the same rank order of IC50-values as LT biosynthesis. The correlation between fMLP/thimerosal-induced LT biosynthesis and Cai levels reveal a Cai threshold of 150 nM for arachidonic acid metabolism. cAMP levels in PMN were elevated by PDE inhibitors alone by less than 2-fold. In the presence of fMLP however, cAMP was increased up to 10-fold and the efficacy of PDE inhibitors to increase cAMP paralleled their potency to inhibit PDE IV. It is concluded that (1) suppression of PMN functions is achieved by PDE IV inhibition, (2) necessary cAMP elevations are within 50% increase, (3) superoxide release was affected by cAMP/protein kinase A (PKA) directly whereas (4) for inhibition of LT biosynthesis a cAMP related reduction of Ca-influx is involved. Send offprint requests to Ch. Schudt at the above address  相似文献   
128.
Summary Pharmacokinetic analysis of epirubicin and its metabolites epirubicinol and 7-deoxy-13-dihydro-epirubicinol aglycone during the first and the fourth courses of treatment was performed in 78 patients with metastatic breast cancer. The patients were treated every 3 weeks with epirubicin given as 10-min i.v. infusions at four different dose levels: 40, 60, 90 and 135 mg/m2. In most cases (76 of 78 cases), plasma concentration-time curves fitted to a three-compartmental pharmacokinetic model. The terminal half-life of epirubicin was independent of dose and duration of treatment. Large interindividual differences were demonstrated (meant 1/2, 21.6±7.9 h; range, 10.6–69 h;n=110). In two subjects, extremely long half-lives and high serum bilirubin concentrations indicated impaired liver function. No correlation was found between the half-life and levels of liver alanine aminotransferase (ALAT) or serum creatinine. The metabolite epirubicinol appeared quickly after epirubicin administration and its half-lives were shorter than that of the parent compound (meant 1/2, 18.1±4.8 h; range, 8.2–38.4 h;n=105).Formation of the aglycone metabolite was delayed and the half-life of this metabolite was shorter than that of epirubicin (meant 1/2, 13±4.6 h; range, 2.7–29 h;n=104). The AUC of epirubicin and the total AUC (drug and metabolites) were linearly proportional to the dose, with the former value constituting two-thirds of the latter. A correlation was found between AUC and the plasma concentration of epirubicin at two time points (2 and 24 h after administration). The proposed model was AUC=9.44×c 2+62.5×c 24+157.7 (r=0.953).This work was supported by the Lundbeck Foundation, the Michaelsen Foundation and Farmitalia Carlo Erba Ltd.  相似文献   
129.
Studies on the mechanisms of transformation of mammalian cells by herpes simplex virus (HSV) in vitro have been prevented so far by the extremely low transformation frequencies obtained in monolayer culture. Here we present a transformation system that relies on the direct seeding in soft agar of infected single cells, thus avoiding negative interactions between normal and transformed cells. We took advantage of HSV-I temperature-sensitive mutants at the UL9 locus, which codes for a DNA-binding protein necessary for viral DNA replication. At the non-permissive temperature, viral DNA synthesis and late gene expression are prevented. Viral gene expression is restricted to immediate early and early genes. Induction of transformation was highly efficient in our one-step transformation system. It depended on intact viral particles and viral DNA. Immediate early and/or early viral gene expression was sufficient to induce transformation. Colonies were stably transformed and did not show any rescue of viable virus after temperature downshift and co-cultivation with susceptible cells. Transformed cells maintained the transformed state in the absence of viral DNA. Our data therefore support the "hit-and-run" hypothesis for the transforming effect of HSV.  相似文献   
130.
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