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Technological properties of components can benefit from the application of modern steel grades. For example, a reduction of fuel consumption or an improvement in vehicle efficiency can be achieved by using high-tensile bainitic steels in automotive industry in order to increase injection pressure in fuel supply. To take advantages like technological progress, sustainability or cost savings the machinability of these materials has to be investigated in order to prepare for a future industrial use of steels with a bainitic structure. In this paper, turning of the bainitic steel 20MnCrMo7+BY in comparison to the quenched and tempered steels 42CrMo4+QT and 50CrMo4+QT is analysed.

In this paper a new three-window high-pressure cell for W/5,5pm spectroscopy of biological systems is described. Such a cell, due to its miniaturisation, fits the most standard small-size spectrometers. The cell of fluid medium, external pressure generation type, is a part of high-pressure system and enables measurements of spectroscopic changes at pressures up to 500 MPa and temperatures -40°C to + 100°C. The exemplary results of measurements of fluorescence of chlorophyll are presented.

Prognostic evaluation of advanced liver disease is usually made on the basis of the common clinical and biochemical data included in the Child-Turcotte classification. The aim of this study was to evaluate the contribution of data from splanchnic angiography as a guide to prognosis in patients with cirrhosis. Over an 8-year period 219 patients with cirrhosis were investigated by splanchnic angiography and followed up prospectively. At the end of the study 95 patients had died (43.4%). Median survival time was 68 months. In addition to several clinical and biochemical data, hepatic portal venous perfusion and the presence of caudad hepatofugal veins as assessed by angiography were significant predictors of survival. Incorporating all non-angiographic variables in a Cox's multiple regression analysis, a clinicobiochemical set of prognostic covariates (ascites, s-albumin, gammaglobulins, s-alkaline phosphatase, and sex) was selected. When adding to this model each of the angiographic variables, only portal perfusion resulted in an independent predictor of survival. In conclusion, in cirrhotics the angiographic evaluation of portal perfusion improved the prognostic information obtained from clinical and biochemical data.

The effects of nadolol on renal haemodynamics and function, and on the renin-angiotensinaldosterone system and on renal prostaglandin production were studied in eighteen cirrhotics.

In 18 cirrhotics with impaired renal perfusion intravenous injection of aminophylline 3 mg/kg b.w. increased mean renal blood flow (133-Xenon washout) from 1.77±0.71 to 1.99±0.44 ml/g/min (p<0.01). No significant change in cardiac output was found. In a further 10 cirrhotic patients the administration of aminophylline 3 mg/kg decreased the mean tubular reabsorption of sodium in the proximal section of the nephron (distal delivery) from 10.5±6.2 to 16.3±16.5 (p<0.01). Free-water production increased as a consequence of the increased supply of sodium to the diluting segment. Thus, aminophylline acts favourably on the functional renal impairment that occurs in hepatic cirrhosis.

Prealbumin plasma level is considered a good index of liver function in liver cirrhosis. However, plasma protein levels depend not only on liver function, but also on amino acid supply which is consequent to nutritional status.

Portal hypertension has been considered a pathogenetic factor in the onset of renal haemodynamic alterations in patients with cirrhosis. This hypothesis is based on experimental evidence, whereas the clinical data are few and contradictory. Mean and cortical renal blood flows were studied in 16 patients with liver cirrhosis before and 20–40 days after a portal-systemic shunt performed by different techniques: nine patients had a non-selective shunt and seven a selective shunt (distal splenorenal according to Warren). Despite a decrease in portal pressure, mean and cortical renal blood flows did not change significantly after surgery, and there was no significant correlation between decrease in portal pressure and modification of renal blood flow. It is concluded that portal hypertension is not a pathogenetic factor in renal hypoperfusion in cirrhosis.

The pathogenesis of renal functional impairment in patients with cirrhosis is still poorly understood, although it is probably linked to intrarenal haemodynamic alterations, such as renal cortical vasoconstriction and opening of intrarenal shunts. To elucidate the intrarenal haemodynamic pattern in patients with cirrhosis, in eight patients with this disease mean renal blood flow (MRBF) and cortical blood flow (CBF) were determined by means of the xenon-133 washout technique; in the same subjects mean intrarenal circulation time for plasma (t) and fastest circulation time for plasma (t0) were determined by means of injection of human serum albumin tagged with technetium-99m into the renal artery. Moreover, cortical vascular volume (CVV) was obtained in all subjects by means of the following formula: CVV CBF X t. Fourteen normal subjects constituted a control group for MRBF, 9 subjects for CBF, and 4 subjects for t, t0, and CVV. In patients with cirrhosis MRBF and CBF were significantly less than in controls; t did not show any significant alterations, whereas t0was significantly shorter than in controls. CVV was also significantly impaired. It is concluded that renal cortical vasoconstriction is a characteristic of the renal haemodynamic pattern in patients with cirrhosis. It is suggested that the decrease in t0is due to the opening of intrarenal shunts and that is likely to be the consequence of renal vasoconstriction.

1. In 37 patients with cirrhosis of the liver of different severity (11 in class A, 18 in class B, and 8 in class C, according to Child's criteria modified by Hobbs), inulin and p-aminohippurate clearances, total fractional protein excretion and the fractional clearances of α1-acid glycoprotein, albumin, transferrin, α2-macroglobulin and β2-microglobulin (in 20 patients) were determined. 2. Inulin clearance was lower than 70 ml/min in 19 patients and p-aminohippurate clearance was lower than 300 ml/min in 20 patients. Total fractional protein excretion was above normal in 19 patients; α1-acid glycoprotein fractional clearance was above normal in 11, albumin fractional clearance in 10, transferrin fractional clearance in five, α2-macroglobulin fractional clearance in three, and β2-microglobulin fractional clearance in 10. 3. The increases in protein excretion were independent of any impairment of renal tubular function. An inverse relationship between protein excretion and the clearances of inulin and p-aminohippurate was found. No difference in protein excretion was found between the three groups of patients with different degrees of liver damage. 4. The results suggest that in cirrhosis an increase in glomerular permeability is frequent, though generally slight; it is correlated with an impairment of kidney function and is independent of the severity of the liver damage.

For nonlocal screened exchange potentials the band structures of K and Cu were calculated by use of the MAPW method. The screening constants were determined by fits to experimental data. The results are compared with other theoretical investigations using HFS exchange. Si calcola la struttura a bande del potassio e del rame con il metodo MAPW usando potenziali di scambio schermato non locali. Le costanti di schermo sono staterminate da dati sperimentali. Si confrontano i risultati con altri studi teorici con scambio HFS. Используя метод MAPW, вычисляются зонные структуры K и Cu для нелокальных экранированных обменных потенциалов. Постоянные экранирования опредеделяются из подгонки экспериментальных данных. Полученные результаты сравниваются с другими теоретическими исследованиями, используя обмен HFS.

The renal response to a maximal water load was evaluated in eight cirrhotic patients free of ascites and without previous evidence of ascites and in seven controls. Fractional sodium reabsorption in the proximal and diluting segment was estimated by clearance methods during hypotonic diuresis. Since phosphate excretion has been proposed as a proximal marker in liver cirrhosis, sodium reabsorption in the proximal tubule was compared with phosphate fractional excretion. In spite of a normal sodium balance during the pre-study period, non-ascitic cirrhotics showed a blunted proximal natriuretic response to maximal water load. In fact sodium excretion during hypotonic diuresis was reduced (p<0.05) and proximal sodium reabsorption increased (p<0.005) in cirrhotics. Fractional phosphate excretion was not impaired in our patients, and no correlation was found between phosphate excretion and proximal sodium reabsorption, as evaluated by clearance methods. This study demonstrates that an increased reabsorption of sodium in the proximal tubule is responsible for the impaired response to maximal water load in non-ascitic cirrhotics. Abnormalities in tubular handling of phosphate may account for the dissociation between proximal sodium reabsorption and phosphate excretion during hypotonic diuresis in these patients.

Summary The investigations on blood flow in liver metastases are interesting from both a pathophysiological and a therapeutic point of view. Available data, however, are few and not definitive, as these studies are complex and difficult to perform.

Summary Nadolol, a non-cardioselective beta adrenoreceptor blocking agent, has been reported to decrease portal pressure without affecting liver function in cirrhotic patients treated for 1 month. There were no data about the long-term effects of nadolol on liver function.

Background: Left ventricular systolic abnormalities have been reported in liver cirrhosis (LC). Diastolic function in cirrhotics, on the contrary, does not seem to have been studied so far. Methods: Diastolic function was evaluated in 42 cirrhotic patients and in 16 controls by means of Doppler echocardiography. Results: Compared with the controls, cirrhotics had increased left ventricular end-diastolic and left atrial volume, stroke volume, late diastolic flow velocity (peak A) (71 ± 17 cm/sec versus 56 ± 18; p < 0.01), time from onset of mitral inflow to the early peak (time E) (86 ± 11 msec versus 72 ± 14; p < 0.003), and deceleration time (DT) (194 ± 40 msec versus 159 ± 27; p < 0.001) and decreased ratio of peak E to peak A filling velocities (1.02 ± 0.35 versus 1.22 ± 0.25; p < 0.02). Patients with tense ascites had a higher E/A ratio (p < 0.03) and a shorter DT (p < 0.03) than patients with mild or no ascites. Conclusions: The impaired left ventricular relaxation in the presence of high stroke volume suggests a myocardial involvement in LC. The pseudonormalization of the E/A ratio and DT in patients with tense ascites could reflect loading conditions masking the relaxation abnormality.

The study was aimed to assess the relationships between distal sodium delivery and renal diluting ability in liver cirrhosis. Renal response to maximal water load was evaluated in 18 cirrhotic patients without ascites, 12 with mild or moderate ascites, and 26 controls. Distal sodium delivery was derived from clearance calculations during the hypotonic diuresis induced by maximal water load. Although ascitic patients showed a greater impairment in free-water excretion, the pattern of the renal response to maximal water load was similar in ascitic and non-ascitic patients; it was characterized by reduced free-water clearance and reduced distal delivery of sodium. Free-water clearance corrected for distal sodium delivery was normal in non-ascitic patients and in the majority (75%) of decompensated cirrhotics, indicating a primary role of an increased proximal sodium resorption in the pathogenesis of the impaired water excretion of these patients. Renal diluting capacity did not correlate with the severity of liver functional impairment, as evaluated by single liver function tests or by Child's criteria.

STUDIES on the mouse globin mRNAs have shown that specific size classes of poly(A) exist in a population of labelled globin mRNAs (refs 1 and 2). These size classes are present in both α and β globin mRNAs (ref. 1) and the overall size of the poly(A) region in these mRNAs decreases with time1. As the three discrete size classes previously reported were observed at one labelling time, we determined whether these same size classes occur at various stages of messenger maturation, as their presence during the overall shortening process could be indicative of a specific degradatory mechanism. The presence of limiting steps in the shortening of the poly(A) region of mouse globin mRNAs is interesting in the light of possible shortening mechanisms and their relationship to poly(A) binding proteins3,4and mRNA stability.