The communication complexity of interval orders is studied within the following model. Two players choose two elements
x and
y and want to determine whether
x<
y holds by exchanging as few bits of ...information as possible. It is shown that an optimal one-way protocol exists by first establishing a rank-optimality result for a subclass of generalized interval orders. It turns out that the deterministic and nondeterministic communication complexities coincide for generalized interval orders. The analogous statement for the complementary relation is true for interval orders in the strict sense while it need not hold for generalized interval orders.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Complete heart block was diagnosed prenatally in 21 fetuses. Associated structural cardiac defects were present in 18 fetuses, in particular complete atrioventricular canal with atrial isomerism (5 ...cases), and 'corrected' transposition of the great arteries (4 cases). Maternal systemic lupus erythematosus was proved in only one case. In 11 fetuses, intra-uterine congestive heart failure with the signs of non-immune hydrops fetalis occurred. In all 11 fetuses, the hydrops was associated with a cardiac defect, in particular complete atrioventricular canal with atrial isomerism in 5 cases. A review of the literature confirms that only the association of complete heart block and cardiac malformation can cause intra-uterine congestive heart failure, whereas in the case of fetal complete heart block without cardiac malformation or with prenatally hemodynamically insignificant cardiac malformation, congestive heart failure is rare. Only 30% of newborns with complete heart block have associated cardiac malformations. In our series, however, 86% of the fetuses with complete heart block had cardiac malformations. The most important reason for this percentage discrepancy is that almost all fetuses with associated severe cardiac defects, in particular atrioventricular canal defects, develop heart failure which frequently results in prenatal death. Thus, fetal deaths are not included in pediatric statistics. Nevertheless, fetuses with isolated complete heart block generally do not develop heart failure and in almost all of the cases are born alive.
Pituitary adenylate‐cyclase‐activating polypeptide (PACAP) has been shown to possess mitogenic activity in various tumor cells. The present study was designed to investigate signal transduction ...mechanisms and expression of the proto‐oncogenes c‐fos and c‐jun linked to the mitogenic effect of PACAP in the pancreatic carcinoma cell line AR4‐2J. PACAP‐(1–27)‐peptide and PACAP‐(1–38)‐peptide, but not the structurally related vasoactive intestinal polypeptide (VIP), potently stimulated 3Hthymidine incorporation and cell number at doses of 0.1–10 nM. Both molecular forms of PACAP strongly increased formation of cAMP and inositol trisphosphate, elevated cytosolic Ca2+ levels and induced mitogen‐activated protein (MAP) kinase activity. Quantitative reverse‐transcription PCR revealed that PACAP‐(1–27)‐peptide and PACAP‐(1–38)‐peptide elevated c‐fos mRNA levels 50–100‐fold, whereas c‐jun mRNA levels increased only moderately (2–3‐fold). The effect of PACAP on c‐jos and c‐jun expression in AR42J cells was rapid (20 min), transient (1–2 h), dose‐dependent (IC50, 0.5 nM) and was abolished by the specific PACAP receptor antagonist PACAP‐(6–38)‐peptide or inhibitors of protein kinase C or tyrosine kinases. Compared with PACAP, epidermal growth factor and gastrin equipotently stimulated c‐fos transcription whereas VIP, secretin, forskolin or phorbol ester showed only marginal effects. Both PACAP‐(1–27)‐peptide and PACAP‐(1–38)‐peptide strongly increased the DNA binding activity of the c‐fos/c‐jun heterodimer transcription factor AP‐1 at 10 nM and also stimulated AP‐1 transcriptional activity up to 20‐fold in AR4‐2J cells. These findings indicate that the mitogenic effect of PACAP mediated via activation of the GTP‐binding protein coupled PACAP/VIP‐1 (PV1) receptor is linked to the MAP kinase cascade, increased expression of the proto‐oncogenes c‐fos and c‐jun and activation of the heterodimeric transcription factor AP‐1.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
A versatile device for a patch-clamp amplifier is described. This device contains: (i) an acoustic indicator to monitor the input resistance of the patch pipette, which is used in search-mode to ...indicate the formation of seals; (ii) two pulse generators; and (iii) a staircase generator to produce various pulse and voltage step programs; (iv) a low-pass filter which is used to filter the output of the patch clamp amplifier; and (v) a remote control which is used to control the entire patch clamp experiment. This remote control is used to switch between search-, current clamp-, and voltage clamp-mode, to activate the respective stimulus potential programs, and to control the tape recorder. This electronic device can be easily connected to patch clamp amplifiers.
Diurnal changes of xylem pressure in the liana Tetrastigma voinierianum have been measured under greenhouse conditions by means of the recently developed xylem pressure probe. During the early ...morning hours, tensions in the vessels developed more or less rapidly with time, depending on light intensity. On sunny days, absolute negative pressures down to about -0.4 MPa (atmospheric = 0.1 MPa) were recorded around noon in petiolar or stem xylem vessels, whereas on rainy or cloudy days the xylem pressure remained in the positive sub-atmospheric or slightly negative pressure range. Towards the evening the tension in the vessels always decreased, i.e. the xylem pressure shifted to about atmospheric, or even above-atmospheric, values during the night. Simultaneous xylem pressure recordings at heights of 1 and 5 m frequently yielded either no gradient in tension at all, or far less than expected from the Cohesion Theory. Occasionally, tension gradients were even opposite to those predicted by this theory. Stem-to-leaves pressure gradients in accord with the Cohesion Theory were recorded only when tension had been developed during sunny days in the upper branches of the liana, because increases in tension were not immediately propagated to the xylem of the leaves at ground level, as would be expected from a strictly coupled hydraulic system. Parallel recordings of the "xylem tension" using the pressure chamber yielded rather variable values ranging from 0.1 to 1 MPa; diurnal pressure changes could not be detected at all. The data are discussed on the basis of the equation for the chemical activity of water. They strongly suggest that the xylem tension induced by transpiration is not the sole force for water ascent. Other forces, such as osmotic pressure or convectional and interfacial forces, which to a remarkable extent have already been postulated for decades, seem to be equally important.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Objectives. To identify and compare tumor- and non-tumor-related predictors of survival after radical prostatectomy and to incorporate the latter into the tumor node metastasis classification of ...prostate cancer. Material and methods. A total of 402 patients who underwent radical prostatectomy (mean follow-up period 6.9 years) were stratified according to postoperative tumor stage, Gleason score, prostate-specific antigen level, age and five comorbidity classifications. Cox proportional hazard models were used to identify independent prognostic factors predicting overall survival. Results. Comorbidity (American Society of Anesthesiologists Physical Status classification), Gleason score and age, but not tumor stage, were independent predictors of overall survival. Based on tumor stage and the identified independent prognostic factors, an easily applicable prognostic score was developed to predict overall mortality. Conclusion. A prognostic classification of radical prostatectomy patients based on Gleason score, comorbidity and age and supplementary to a coarsened variant of the tumor node metastasis classification may be of clinical value.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Homocystinuria due to cystathionine-β-synthase deficiency (CBS-def-HOCY) initially often presents with vascular disorders, e.g. thromboembolic events. The measurement of vascular endothelial markers ...in plasma could help to assess endothelial damage. We determined von Willebrand factor (measured as Ristocetincofactor, RiCoF) and thrombomodulin (TM), two endothelial cell markers to our knowledge not measured systematically before in homocystinuria patients in a longitudinal study of two homocystinuric patients: Patient1 with thromboembolic disease and his asymptomatic sister, patient2. Before start of therapy in patient 1, TM and RiCoF levels both were increased. In patient 2 a moderately elevated RiCoF and a normal level of TM were found. Vitamin therapy with 15 mg folate and 600 mg pyridoxine per day led to almost complete normalization of amino acids in urine and plasma, and complete normalization of RiCoF and TM levels in both patients. Thus, TM and RiCoF elevations demonstrate that CBS-def-HOCY leads to endothelial cell damage, which resolved under vitamin therapy in the patients studied.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Diagnosis of chondromalacia of the patellofemoral joint using three-dimensional gradient-echo sequences was investigated in 41 patients, with arthroscopic verification in 25 patients. In vitro ...examinations in human cadaveric patellae were performed in order to determine optimal imaging parameters. FLASH (TR = 40 ms, TE = 10 ms, flip angle = 30 degrees) and FISP (TR = 40 ms, TE = 10 ms, flip angle = 40 degrees) were used in clinical studies. Advanced stages of chrondromalacia could be visualized with high sensitivity. In less advanced disease, overstaging was observed. The therapeutically relevant differentiation of major and minor degrees of chondromalacia seems to be possible. 30 degrees FLASH-images in the axial plane proved to be the most efficacious technique for the diagnosis of chondromalacia.
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