On the spectrophotometric flow injection determination of chromium(VI) in natural waters after on-line preconcentration on activated alumina.

The feasibility of chromium(VI) preconcentration on to activated alumina in a continuous flow system with spectrophotometric detection was investigated. Chemical and flow variables, and the influence of concomitant species were studied both with and without preconcentration systems. The best results were obtained by using a 2.

Deontological aspects in recombinant DNA researches.

Legal problems exist in regard to patent rights for new biotechnologies. Ethical problems arise in connection with the application of the technique to patients and with the possibility to cure embryos. The potentialities of preventive medicine have affected even hiring criteria, in that individuals who present enzymic deficiencies can be considered at risk when working in contact with certain substances.

Information about morality and behaviour of victims.

According to the Italian Law of Procedure (1988) documents which inform about the morality of the guilty, the witness and the victim are not admitted; those about the victim are admitted only when the criminal event needs to be evaluated in relation to his/her behaviour and moral qualities. In our opinion, in this case, generic moral qualities do not have any real significance; only information about the victim's objective behaviour should be admitted: for instance, in the case of the crime of "corruption of a minor", a type of objective behaviour can be habitual prostitution. Moreover, the norm at issue contrasts with the general principle in the Italian law that the rights concerning the personality of an individual, particularly of a minor, are to be protected, and with the fundamental norm in the law of Procedure according to which criminological examinations are not allowed during the trial.

Renal handling of urea in subjects with persistent azotemia and normal renal function.

Fourteen subjects with persistent azotemia and normal glomerular filtration rate were studied by renal clearances and hormonal determinations to establish the nephron site of altered urea transport and the mechanism(s) responsible for their azotemia. During constant alimentary protein, urea nitrogen appearance was normal and urea clearance was much lower than in 10 age-matched control subjects (23.3 +/- 2.

Angiotensin II inhibition with captopril on plasma ADH, PG synthesis, and renal function in humans.

Using captopril (C), an angiotensin (ANG) I converting-enzyme inhibitor, to increase endogenous prostaglandins (PGs) and to decrease endogenous ANG II synthesis, we studied the relationship between endogenous ANG II, PG, and antidiuretic hormone (ADH) release in seven normal volunteers before (control study) and after inhibition of PG synthesis by a single dose of aspirin (ASA study). In the control study, following the administration of 100 mg of C, there was a significant increase of plasma PGE2, plasma-renin activity (PRA), and urinary PGE2 and 6-keto-PGF1 alpha and a decrease of plasma ADH. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were unaffected by C; urine output, fractional sodium excretion (FENa), and osmolal clearance (Cosmol) increased; and urinary osmolality (Uosmol) decreased significantly after C.

Effects of angiotensin II on plasma ADH, prostaglandin synthesis, and water excretion in normal humans.

To verify whether angiotensin II (ANG II) stimulates ADH release in humans and to evaluate whether endogenous prostaglandins influence the resulting renal effect of ADH, nonpressor and low pressor doses of ANG II were infused in nine normal volunteers under normal conditions (control study) and after prostaglandin synthesis inhibition with aspirin (ASA study). During ANG II infusion plasma ADH increased in both conditions. Plasma PGE2, urinary PGE2, and urinary 6-keto-PGF1 alpha increased only in the control study, whereas they were undetectable in the plasma and significantly reduced in the urine in the ASA study.