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Objectives: The purpose of this prospective clinical study was to identify the bacterial spectra on the surface of oral squamous cell carcinomas (OSCC) in comparison to oral mucosa of patients with a higher risk to emerge an OSCC and a control group to determine their susceptibility to various common antibiotics. Material and methods: Swabs from 90 patients, 30 patients of each group, were cultured on media for aerobes and anaerobes and tested with agar diffusion and Etest. Results: The predominant pathogens of the normal healthy oral mucosa were aerobes. The ratio between aerobes and anaerobes was 2:1, balanced in risk patients and inverted in the OSCC group. Altogether, 1,006 isolates were cultured. The most frequent strains were 47 viridans streptococci, 30 S taphylococcus species, 14 Enterococcus faecalis, 36 Neisseria species, 14 Escherichia coli, and 23 other aerobes, 66 Peptostreptococcus species, 39 Fusobacterium species, and 34 Prevotella species. The resistance rates in the OSCC group were penicillin 40 %, ampicillin 57 %, doxycycline 23 %, clindamycin 47 %, and amoxicillin/clavulanic acid 20 %, but up to 100 % of pathogens were susceptible to azithromycin, telithromycin, levofloxacin, and moxifloxacin. Conclusion: Gram-negative anaerobes play a decisive role in the development of postoperative infections in patients with OSCC. This tumor special type of colonization does not agree with the normal flora of the oral cavity. Clinical relevance: Biofilms on OSCC surfaces provide an important reservoir for anaerobic bacteria. As a consequence, a proposal for an antibiotic prophylactic regime should be given. [ABSTRACT FROM AUTHOR]

Demonstrates that specific connections are established in an organotypic culture system, in which rat visual cortex slices are co-cultured with another slice of the visual cortex or with a thalamic slice. Methods; Results; Discussion.

Auditory brain stem evoked responses (BSERs) were recorded from schizophrenic and depressed patients and healthy subjects. Between these groups no differences in latencies, amplitudes and variability of the BSERs were found. [ABSTRACT FROM AUTHOR]

Mössbauer spectra forSn in crystalline and disordered Sn, as well as in crystalline and liquid-like amorphous SnCu ( X=0.10−0.18), have been measured at 2.6 K≦ T≦108 K. The Debye-Waller-Factor (DWF) obtained from the spectra is identical for the crystalline and for the disordered phase. The DWF of the amorphous phase is smaller than the DWF of the crystalline phase at high temperatures, but it shows a stronger temperature dependence than the DWF of the crystalline phase and reaches the latter one at about 4 K. From this low-temperature result we conclude that the differences of the Eliashberg function α( ω) F( ω) and of the superconducting transition temperature T in these two phases cannot be related to changes in the phonon spectrum F( ω), but must result from changes of the interaction parameter α ( ω). A comparison between DWF, α F, and specific heat data is performed. From the values for the isomeric shift of the Mössbauer line we can show that the hybridisation and covalency of the electronic bonds present in the crystalline and in the disordered phases are destroyed in the amorphous phase. Both, the DWF and the isomer shift demonstrate that the electronic properties of crystalline and amorphous Sn(Cu) differ appreciably. The electronic and superconducting properties of amorphous Sn(Cu) are similar to the properties of the high pressure phase of tin. [ABSTRACT FROM AUTHOR]

Slice cultures from the visual cortex of young rats were prepared using the roller culture technique (Gähwiler 1984). After 10 days in vitro the cortical cultures flattened to 1-3 cell layers, surviving for up to 12 weeks. The cultures were organotypically organized, the typical layered structure of the cortex was preserved. The neuronal composition of slice cultures was studied using intracellular staining, Golgi impregnation and GABA immunohistochemistry. Both pyramidal cells and several types of nonpyramidal cells were identified in the slice cultures. Electrophysiological recordings showed that the electrical properties of cells in culture were similar to those measured in acute slice preparations; for some cells, however, the spontaneous activity was higher. The maintained activity was strongly increased by application of the GABA antagonist bicuculline and decreased by GABA, suggesting that GABAergic inhibition is present in these preparations. We could observe the postnatal maturation of some characteristic morphological features in culture. For example, pyramidal cells in 6 day-old rats in situ have very short basal dendrites with growth-cones, and the dendrites are free of spines. After 2-3 weeks in culture growth-cones were no longer observed. Instead, the cells had developed a large basal dendritic field and the dendrites were covered with spines. Slice cultures therefore may provide a useful tool for physiological, anatomical, pharmacological and developmental studies of cortical neurons in an organotypical environment. [ABSTRACT FROM AUTHOR]

Mössbauer spectra ofSn in SnEuMoS ( z=0, 1/3, 2/3) have been measured in the temperature range 4.9 K≦ T≦293 K. The spectra consist of a quadrupole doublett with unequal intensities at all temperatures. The Debye-Waller factor, the isomeric shift and the asymmetry of the intensity of the quadrupole components show irregularities between 50 K and 110 K which are interpreted as arising from a structural phase transition. The temperature dependence of the Debye-Waller factor can be approximated by a simple phonon spectrum. No quantitative explanation can be given for the large values of the asymmetry. Evidence is presented that this behavior is connected with the properties of the librational modes of the MoS-units in the crystal. [ABSTRACT FROM AUTHOR]

The behavior of the proton magnetic form factor is studied within the modified hard scattering picture, which takes into account gluonic radiative corrections in terms of transverse separations. We parallel the analysis given previously by Li and make apparent a serious objection. The appropriate cut-off needed to render the form-factor calculation finite is both detailed and analyzed by considering different cut-off prescriptions. The use of the maximum interquark separation as a common infrared cut-off in the Sudakov suppression factor is proposed, since it avoids difficulties with the α-singularrities and yields a proton form factor insensitive to the inclusion of the soft region which therefore can be confidently attributed to perturbative QCD. Results are presented for a variety of proton wave functions including also their intrinsic transverse momentum. It turns out that the perturbative contribution, although theoretically self-consistent for Q larger than about 6 GeV to 10 GeV, is too small compared to the data. [ABSTRACT FROM AUTHOR]

Current light-cone wave functions for the nucleon are unsatisfactory since they are in conflict with the data of the nucleon's Dirac form factor at large momentum transfer. Therefore, we attempt a determination of a new wave function respecting theoretical ideas on its parameterization and satisfying the following constraints: It should provide a soft overlap contribution to the proton's form factor in agreement with data; it should be consistent with current parameterizations of the valence quark distribution functions and lastly it should provide an acceptable value for the J/ψ → N N decay width. The latter process is calculated within the modified perturbative approach to hard exclusive reactions. A simultaneous fit to the three sets of data leads to a wave function whose x-dependent part, the distribution amplitude, shows the same type of asymmetry as those distribution amplitudes constrained by QCD sum rules. The assymetry is however much more moderate as in those amplitudes. Our distribution amplitude resembles the asymptotic one in shape but the position of the maximum is somewhat shifted. [ABSTRACT FROM AUTHOR]

A method is proposed to extend the hard scattering picture of Brodsky and Lepage to transitions between hadrons with orbital angular momentum l=0 and l=1. The use of covariant spin wave functions turns out to be very helpful in formulating that method. As a first application we construct a light-cone wave function of the nucleon resonance N(1535) in the quark-diquark picture. Using this wave function and the extended hard scattering picture, the N-N transition form factors are calculated at large momentum transfer and the results compared to experimental data. As a further application of our method we briefly discuss the π- a form factors in an appendix. [ABSTRACT FROM AUTHOR]

In the imagines of the mealworm Tenebrio molitor vigorous head movements during walk have been observed. This head waving is absent in resting animals. The time course of the head movement in the horizontal plane of the tethered animals was registered by means of a television camera and its power spectrum, autocorrelation function as well as the distribution of the head's angular position have been calculated. In non-homogeneous stationary panoramas, which are symmetrical with respect to the body axis the process governing the head waving is quasi-Gaussian, its power spectrum is a slowly declining exponential function of the frequency. In asymmetrical panoramas the distribution of the angular position of the head becomes also asymmetrical, and its average value is shifted with respect to the body axis. In homogeneously bright surroundings the process is the superposition of a quasi Gaussian and of a symmetrical periodic function, thus indicating a regular searching movement in addition to the random head waving. The possible role of the head waving for the fixation response is discussed. [ABSTRACT FROM AUTHOR]

Tethered walking imagines of the mealworm beetle Tenebrio molitor wave their heads in random fashion. If a periodic pattern of vertical black and white stripes is rotated around the animal a regular nystagmic head movement is superimposed upon the random waving, the frequency of the latter equals the contrast frequency within large ranges of the angular velocity of the pattern. The nystagmus is inverted: After a short period of tracking, during which the angular velocity of the head is the same as that of the panorama, the head returns slowly toward its normal position according to an exponential-like function. Resting animals do not wave their heads. However, if the above panorama is rotated, the beetle turns its head in the direction of the movement of the panorama and holds it in a side-way position, as long as the rotation is maintained. The angular position reached depends in the same manner on the angular velocity of the panorama as the turning tendency of walking animals established in open loop experiments using the spherical Y-maze method. [ABSTRACT FROM AUTHOR]

Head movements of different species of walking beetles elicited by rotating stripe patterns have been investigated. They are of the usual type in contrast to an 'inverted nystagmus' reported for Tenebrio molitor in similar experimental situations. Reexamination of the Tenebrio records revealed that the sign of the stimulus was interchanged by a mistake while plotting the results. Thus, the head nystagmus in Tenebrio is also of the usual type, consisting of a smooth pursuit head movement followed by a faster returning phase. [ABSTRACT FROM AUTHOR]