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Modern treatment strategies, consisting of intensive chemotherapy and cranial irradiation, have remarkably improved the prognosis for children with acute lymphoblastic leukemia. However, patients with a potential for cure are at risk of severe acute and late adverse effects of treatment. Furthermore, in 25-30% of patients treatment still fails. The objectives of the DCLSG study ALL 8 were to decrease the toxicity and to increase the effectivity of BFM-oriented treatment. Decrease of toxicity was aimed at by confirmation of the results of the previous DCLSG study ALL-7, showing that the majority (94%) of children with ALL can succesfully be treated with BFM-oriented therapy without cranial irradiation, and by reduction of treatment for standard risk (SRG) patients. To increase the cure rate in medium risk (MRG) patients the efficacy of high doses of intravenous 6-mercaptopurine (HD-6MP) during protocol M and in SRG patients the efficacy of high doses of L-asparaginase (HD-L-ASP) during maintenance treatment was studied in randomized studies. Patient stratification and treatment were identical to protocol ALL-BFM90, with the following differences: no prophylactic cranial irradiation, SRG patients received only phase 1 of protocol I. Four hundred and sixtyseven patients entered the protocol: 170 SRG, 241 MRG and 56 HRG patients. The 5 years event-free survival rate for all patients was 73% (s.e. 2%); for SRG, MRG and HRG patients 85% (s.e. 3%), 73% (s.e. 3%) and 39% (s.e. 7%), respectively. In patients Ͼ1 year of age at diagnosis unfavorable prognostic factors were male sex, Ͼ25% blasts in the bone marrow at day 15 and initial white blood cell count (WBC) Ͼ50 × 10 9 /l. The cumulative risk of CNS relapse rate was 5% (s.e. 1%) at 5 years. These results confirm that the omission of cranial irradiation in BFM-oriented treatment does not jeopardize the overall good treatment results, nor does early reduction of chemotherapy in SRG patients. No benefit was observed from treatment intensification with HD-L-ASP in SRG patients, nor from HD-6MP in MRG patients.

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The mechanics underlying undulatory swimming are of great general interest, both to biologists and to engineers. Over the years, more data of the kinematics of undulatory swimming have been reported. At present, an integrative analysis is needed to determine which general relations hold between kinematic variables. We here perform such an analysis by means of a meta‐analysis. Using data of 27 species, we examine the relationships between the swimming speed and several kinematic variables, namely frequency and amplitude of the tail beat, length and speed of the propulsive wave, length of the body, the Reynolds number, the Strouhal number and the slip ratio U/V (between the forward swimming speed U and the rearward speed V of the propulsive wave). We present results in absolute units (cm) and in units relative to the length of the organism (total length, TL). Our data show several kinematic relations: the strongest influence on swimming speed is the speed of the propulsive wave, and the other variables (amplitude and frequency of the tail beat, length of the propulsive wave and length of the body) influence it more weakly (but significantly). In several cases, results differ when variables are expressed in different units (absolute or relative to length). Our data reveal significant differences between kinematics of swimming of shallow‐bodied and deep‐bodied individuals, with shallow‐bodied ones swimming with a shorter propulsive wave length and a higher Strouhal number. The slip ratio U/V and the Strouhal number appear to depend on the Reynolds number in a non‐linear manner.

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