Effect of the dilution rate on microbial competition: r-strategist can win over k-strategist at low substrate concentration.

The conditions present in both in vitro and in vivo ecosystems determine the microbial population harbouring it. One commonly accepted theory is that a species with a high substrate affinity and low growth rate (k-strategist) will win the competition against a second species with a lower substrate affinity and higher growth rate (r-strategist) if both species are subjected to low substrate concentrations. In this study two nitrite oxidizing bacteria (NOB), Nitrospira defluvii (k-strategist) and Nitrobacter vulgaris (r-strategist), were cultivated in a continuous reactor systems.

Treatment of high-grade, high-stage prostate cancer with estramustine phosphate or diethylstilbestrol. A double-blind study. The SPCG-1 Study Group. Scandinavian Prostate Cancer Group.

Between 1984 and 1989, 197 patients with T1-4, NX, M1, G2-3 or G3 prostate cancer were randomized to treatment with 560 mg estramustine phosphate (EMP, Estracyt, Emcyt) or 3 mg diethylstilbestrol (DES) per day in a double blind study with stratification on presence or absence of cancer pain at start. A total of 194 patients were evaluated for efficacy of therapy. Time to progression (p = 0.

Oat mesophyll protoplasts: their response to various feeder cultures.

Oat (Avena sativa L.) mesophyll protoplasts were recently demonstrated to be capable of dedifferentiation, repeated divisions, and colony formation. Since the development of oat mesophyll protoplasts is decisively influenced by the nature of the used feeder culture (species, variety and concentration), we conducted a systematic study of this parameter.

Colony formation from mesophyll protoplasts of a cereal, oat.

Differentiated leaf cells of gramineous plants, among them the cereals with their immense importance for human nutrition, are considered extremely recalcitrant to, if not incapable of, reentering the cell cycle. This recalcitrance is related to the poor wound response of the monocots-in contrast to most dicots-and the difficulties encountered in monocot tissue culture. We report here the highly reproducible induction of sustained divisions at high frequency (up to 95%) and colony formation from mesophyll protoplasts of a cereal, oat, demonstrating that-contrary to most earlier evidence-mesophyll cells of a gramineous plant have not irreversibly lost their potential for cell division.

Cytogenetics of protoplast cultures of Brachycome dichromosomatica and Crepis capillaris and regeneration of plants.

Callus derived protoplasts of Brachycome dichromosomatica (2n=2x=4) and Crepis capillaris (2n=2x=6) have been regenerated into karyologically normal plants, i.e. plants without visible alterations of the diploid chromosome set.

Renal vasodilation after unilateral renal ablation.

Renal blood flow was studied in rats 120 minutes after unilateral renal ablation. The influence of endogenous prostaglandin formation was evaluated by indomethacin treatment prior to the ablation. Radioactive microspheres were used for estimation of the total renal and cortical blood flow, and the renal medullary blood flow was determined with the 86-Rb chloride extraction method.

The effect of intraarterial infusion of prostacyclin on the tubuloglomerular feedback control in the rat.

Effects of intraarterial prostacyclin (PGI2) infusions on interstitial hydrostatic and oncotic pressures and on the tubuloglomerular feedback (TGF) control of glomerular filtration rate (GFR) were studied in rat kidneys. The hilar lymph flow rate was used as a measure of interstitial hydrostatic pressure and the lymph protein concentration was used for interstitial oncotic pressure estimation. In the micropuncture experiments the stop-flow pressure technique was employed for determining the TGF characteristics, i.

Prevention of interstitial pressure change at unilateral nephrectomy by prostaglandin synthesis inhibition.

The mechanisms underlying the adaptive process in the remaining kidney after unilateral nephrectomy are not well known. In the present study adaptive changes in interstitial pressure conditions following uninephrectomy were investigated in male Sprague-Dawley rats. Direct subcapsular hydrostatic pressure recordings were made via microcatheters , renal lymph was collected for lymph flow rate estimations and determinations of lymph protein content and the urine flow rate and urinary excretion of sodium and potassium were measured, before and after contralateral nephrectomy.

Indomethacin inhibits renal functional adaptation to nephron loss.

Immediately after unilateral nephrectomy, the glomerular filtration rate (GFR) and urinary excretion rate increase in the remaining transplanted rat kidney. In a previous study, we found that GFR in a transplanted kidney was reduced through an activation of the tubuloglomerular feedback control. Excision of the rat's own remnant kidney then reduced feedback sensitivity and thereby allowed GFR to rise.

The effect of tubular perfusion with PGE2, PGF2 alpha, and PGI2 on the tubuloglomerular feedback control in the rat.

The prostaglandins (PG) of the renal medulla might affect the nephron and the cortical arteriolar function via the tubular route. To investigate this question PGE2 (1 microgram/mL), PGF2 alpha (10 micrograms/mL), or PGI2 (1 ng/mL) was added to the tubular perfusion solution when the characteristics of the tubuloglomerular feedback (TGF) control were measured. The experiments were performed on Sprague-Dawley rats.

Microsurgical replantation of an amputated penis.

The microneurovascular replantation of a completely amputated penis is described. Fifteen hours after the replantation an arterial reanastomosis was performed due to a secondary thrombosis. The result after 3 months is excellent, with returned capacity of erection.

Vesical neck closure versus balloon catheter in suprapubic prostatectomy: a controlled clinical trial.

In a randomized trial comprising 102 cases of suprapubic prostatectomy a modified Hryntschak technique of vesical neck closure was compared to the balloon compression method. There were no statistically significant differences between the 2 groups in operative and postoperative blood loss, duration of operation or postoperative hospital stay. In the vesical neck closure group compared to the balloon catheter group more patients experienced catheters falling out prematurely, as well as more postoperative strictures and more cases of incontinence at followup 1 year later.

[Microscopic investigation of the partial stages of dissolution processes in urinary calculi (author's transl)].

The formation of urinary calculi cannot yet be prevented with certainty. Consequently the dissolution of stones remains a focus of medical interest. The speed of solution of a calculus is not a quantity typical of the substance, but depends largely on the structural formation of the urinary calculi.