[But...was there ever a Clark classification of melanomas?].

For the past 40 years, the Clark classification of cutaneous melanoma has been accepted and used by the vast majority of dermatologists and pathologists throughout the world. However,after careful rereading of the most relevant articles by Clark and his collaborators, we can affirm that the classification was only ever of passing validity. Today, the possible morphological differences between one case of cutaneous melanoma and another are of no proven prognostic implication.

Unna's and Miescher's nevi: two different types of intradermal nevus: hypothesis concerning their histogenesis.

In 1991, we tentatively introduced the classification of Ackerman and Magana-García for acquired melanocytic nevi in our laboratory. We soon realized that every acquired intradermal melanocytic nevus might be easily classified into either Unna's or Miescher's patterns and that this classification had both clinical implications and significant histological differences. The decisive discriminative feature between Unna's and Miescher's nevi is that Unna's nevus is an almost purely adventitial lesion confined to expanded papillary dermis and, many times, to the perifollicular dermis too.

Dielectron production in 12C+12C collisions at 2A GeV with the HADES spectrometer.

The invariant-mass spectrum of e+e- pairs produced in 12C+12C collisions at an incident energy of 2 GeV per nucleon has been measured for the first time. The measured pair production probabilities span over 5 orders of magnitude from the pi(0)-Dalitz to the rho/omega invariant-mass region. Dalitz decays of pi(0) and eta account for all the yield up to 0.

The fast neutron component in treatment irradiations with 12C beam.

Using 12C beams of 200 AMeV kinetic energy the production of secondary fragments from nuclear reactions in a thick water absorber (12.78 cm) was investigated. Fast neutrons and energetic charged particles (p-, d-, t-, a-particles) emitted in the forward hemisphere were identified by a BaF2/plastic-scintillation detector telescope.

Fast neutrons produced by nuclear fragmentation in treatment irradiations with 12C beam.

In the framework of the heavy-ion tumour therapy project at GSI we investigated the nuclear fragmentation of 200 AMeV carbon ions stopping in a 12.78-cm thick water absorber. Fast neutrons and charged particles emerging from the target were registered at forward angles between 0 degrees and 30 degrees with a DeltaE-E-telescope consisting of an NE102 and a BaF2 scintillator.

Exclusive measurement of coherent proton-deuteron bremsstrahlung.

For the first time a high-precision proton-deuteron bremsstrahlung experiment has been performed in which all the different exit channels have been distinguished separately. High-precision cross sections and analyzing powers in one of the outgoing channels, namely, the coherent bremsstrahlung with a proton and a deuteron in the final state, are presented at 190 MeV incoming proton beam energy and are compared to calculations based on the low-energy theorem. The results of the calculations vary considerably calling for a fully microscopic calculation.

Aspergillus aortitis after cardiac surgery.

Objectives: The aim of this study was to describe the clinical characteristics of Aspergillus aortitis in a small series of consecutive patients.

Background: Aspergillus infection of the ascending aorta after cardiopulmonary bypass surgery has rarely been reported and has always resulted in death.

Methods: Aspergillus aortitis was confirmed by pathologic and microbiologic analysis in eight men (61 +/- 8 years) of 9,375 consecutive patients who underwent cardiac surgery between 1975 and 2000.

Suppression of soft nuclear bremsstrahlung in proton-nucleus collisions.

Photon energy spectra up to the kinematic limit have been measured in 190 MeV proton reactions with light and heavy nuclei to investigate the influence of the multiple-scattering process on the photon production. Relative to the predictions of models based on a quasifree production mechanism, a strong suppression of bremsstrahlung is observed in the low-energy region of the photon spectrum. We attribute this effect to the interference of photon amplitudes due to multiple scattering of nucleons in the nuclear medium.

Multinodular pilomatrixoma.

A hard deep nodule, 6 x 3 mm in size, was excised from the cheek of a 12-year-old girl. The histological sections showed a multinodular cyst-like proliferation, each nodule showing the typical structure and cytology of pilomatrixoma. A comparison is made between this case and the budding phenomenon that has been described in isthmus-catagen (tricholemmal) cyst.

Primary osteosarcoma of the uterine corpus: report of a case with immunohistochemical and ultrastructural study.

Background: Primary uterine osteosarcoma is extremely rare, with only 15 cases reported in the literature.

Case: A 41-year-old woman presented with abnormal vaginal bleeding due to a large tumor arising from the uterine corpus. Histologically, the tumor showed the features of a malignant mesenchymal neoplasm with osteoid formation and lacked an epithelial component.

Coherent bremsstrahlung in the alpha + p system at 50 MeV/nucleon.

Photons originating from coherent bremsstrahlung have been measured over a large dynamic range for the reaction of 200 MeV alpha particles with protons. At low photon energies the bremsstrahlung spectrum exhibits the classical behavior with an approximate 1/E(gamma) shape. At higher photon energies there is a pronounced contribution from capture into the unbound ground state and first excited state of 5Li.