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991.
MR Robinson MB Shetty B Richards J Bastable RW Glashan PH Smith 《Canadian Metallurgical Quarterly》1977,118(6):972-973
Of 48 patients with bladder tumors treated with intravesical epodyl 17 have shown a complete remission at some stage of treatment, although several have relapsed later. Partial remission occurred in 20 patients and 11 have shown no improvement or the lesions have progressed. Epodyl is used best as an adjunct to transurethral resection or diathermy of T1 bladder lesions. Even in patients who do not show complete remission epodyl may reduce the incidence of recurrence and the number of lesions. It is useful when rapid recurrence of T1 bladder tumors prevents control by resection or diathermy and it also is beneficial as an emergency measure to control hematuria. Complications are not infrequent and may be severe occasionally. Bone marrow depression has been seen in 2 patients whose bladders showed extensive carcinoma in situ. 相似文献
992.
Peter T. Saunders Michael J. Bazin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(11):847-853
Pirt's theory in which microbial growth in a packed column is considered to be limited by diffusion of nutrient is modified and extended to include a consideration of two species systems. Equations are derived to describe the fate of a substrate when the substrate itself is limiting microbial growth and when oxygen is limiting. In the latter case reactions obey zero order kinetics while in the substrate limited process 'half-order' kinetics occur. Theoretical considerations imply that limitation of microbial growth by surface area availability is unlikely. The limited experimental data available supports this conclusion but when the same data is applied to the theory of the active layer the results are inconclusive. Even if correct, the theory is not likely to be important in effluent purification. 相似文献
993.
994.
995.
J. Saunders R. Ling W. Wojtanowski E. R. Dobbs 《Journal of Low Temperature Physics》1990,79(1-2):75-91
The attenuation of zero sound in superfluid3He-B has been measured up to 160 cm–1, at pressures less than 4 bar and at frequencies 34.2, 44.2, and 54.0 MHz. The contribution of pair breaking to the attenuation has been measured for the first time. The gap (J=1
–) mode has been studied in magnetic fields up to 80 mT and the structure of its Zeeman components revealed. Coupling to the gap mode in the applied field allows a direct spectroscopic measurement of the energy gap. In zero magnetic field, the attenuation is well described by the theory of Wölfle, showing agreement with the magnitude of the attenuation and the frequency of the squashing mode resonance, for an appropriate choice of the parameterz=(c
0–c1)/c1, wherec
0, c1 are the velocities of zero and first sound. This provides a determination of the Landau parameterF
2
s
and indicates that thef-wave interaction is negligible at these low pressures. 相似文献
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997.
998.
Many neurons of the central nervous system display multiple high voltage-activated Ca2+ currents, pharmacologically classified as L-, N-, P-, Q-, and R-type. Of these current types, the R-type is the least understood. The leading candidate for the molecular correlate of R-type currents in cerebellar granule cells is the alpha1E subunit, which yields Ca2+ currents very similar to the R-type when expressed in heterologous systems. As a complementary approach, we tested whether antisense oligonucleotides against alpha1E could decrease the expression of R-type current in rat cerebellar granule neurons in culture. Cells were supplemented with either antisense or sense oligonucleotides and whole-cell patch clamp recordings were obtained after 6-8 days in vitro. Incubation with alpha1E antisense oligonucleotide caused a 52.5% decrease in the peak R-type current density, from -10 +/- 0.6 picoamperes/picofarad (pA/pF) (n = 6) in the untreated controls to -4.8 +/- 0.8 pA/pF (n = 11) (P < 0.01). In contrast, no significant changes in the current expression were seen in sense oligonucleotide-treated cells (-11.3 +/- 3.2 pA/pF). The specificity of the alpha1E antisense oligonucleotides was supported by the lack of change in estimates of the P/Q current amplitude. Furthermore, antisense and sense oligonucleotides against alpha1A did not affect R-type current expression (-11.5 +/- 1.7 and -11.7 +/- 1.7 pA/pF, respectively), whereas the alpha1A antisense oligonucleotide significantly reduced whole cell currents under conditions in which P/Q current is dominant. Our results support the hypothesis that members of the E class of alpha1 subunits support the high voltage-activated R-type current in cerebellar granule cells. 相似文献
999.
1000.
One hundred and twenty-nine canine mammary tumours of varying histological types were examined for the presence of oestrogen binding protein by the dextran-coated charcoal method with the binding parameters of the reaction determined by Scatchard plots. By this method, 39 per cent of the 129 mammary tumours were shown to contain oestrogen receptor protein. This figure fell to 25 per cent for benign tumours and rose to 52 per cent for malignant tumours. There was no correlation between the histological nature of tumours and oestrogen receptor content in either benign or malignant forms. Oestrogen receptors were not demonstrable in normal mammary tissues. Whether the presence of oestrogen receptors in a tumour is indicative of hormonal dependence as is reported for human breast tumours is being investigated in the bitch. 相似文献