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31.
Ralph Madeb Dragan Golijanin Joy Knopf Craig Nicholson Stuart Cramer Frederick Tonetti Kelly Piccone John R. Valvo Louis Eichel 《Journal of robotic surgery》2007,1(2):145-149
Several recent studies have suggested that thought leaders in radical prostatectomy have decreased their own positive margin
rates by switching from open to robot-assisted radical prostatectomy. Theoretically, this improvement is largely attributed
to enhanced visualization of the deep pelvis and precision of dissection afforded by the instrumentation. To date, it has
not been determined if this phenomenon exists amongst non-fellowship-trained urologists in private practice. Herein, we describe
the positive margin rates of two non-fellowship-trained private-practice urologists who converted from open radical retropubic
prostatectomy to robot-assisted radical prostatectomy. The margin positivity data from two non-fellowship-trained private-practice
urologists (surgeon 1 and surgeon 2) were reviewed retrospectively. The last 50 cases of open radical retropubic prostatectomy
from each surgeon were compared with the first 50 robotic prostatectomy cases of surgeons 1 and 2, respectively. A positive
surgical margin was defined as tumor present at the inked margin of the prostate. There was a significant decrease in the
overall and pT2 positive margin rates for both surgeons. The overall positive margin rate and pT2 positive margin rate for
surgeon 1 dropped from 44 to 20% and from 37 to 5.7%, respectively, after changing from open to robotic prostatectomy. For
surgeon 2, the overall positive margin rate changed from 26 to 18% and the pT2 positive margin rate changed from 27.5 to 7%
after converting. Changing from open to robotic-assisted radical prostatectomy may improve the ability of urologists to obtain
negative surgical margins. With proper training this phenomenon does seem to apply to non-fellowship-trained urologists in
private practice and can be realized within the first 50 cases performed. 相似文献
32.
P K Donnelly A R Simpson A D Milner M L Nicholson T Horsburgh P S Veitch P R Bell 《Nephrology, dialysis, transplantation》1990,5(9):808-811
Whilst HLA matching is routine for renal transplantation, the possible benefits of matching donor and recipient age have not been previously examined. In this study we examined the simultaneous effect of donor to recipient age difference on the graft survival of 141 consecutive first cadaver transplant recipients treated by cyclosporin immunosuppression. Multivariate regression analysis, taking into account other variables of moderately matched recipients (i.e. dialysis time and type, donor/recipient sex, local/imported kidneys, recent sensitivity, total ischaemic time, preoperative transfusions), indicated that age-difference was the single most important variable (P less than 0.05). Individually there was no significant effect of recipient age, whilst older donors (aged greater than 50 years) were associated with significantly worse graft survival than those younger (P less than 0.01). When dealing with donors aged greater than or equal to 50 years the corresponding recipient 1-year graft was improved when the donor was no more than 5 years older than the transplant recipient. Donor age to recipient age difference is a potentially important selection criterion in renal transplantation. 相似文献
33.
Species-dependent differences in the properties of particulate cyclic nucleotide phosphodiesterase from rat and rabbit ventricular myocardium 总被引:3,自引:0,他引:3
M Shahid M Wilson C D Nicholson R J Marshall 《The Journal of pharmacy and pharmacology》1990,42(4):283-284
The ability of cyclic nucleotide phosphodiesterases (PDEs) to hydrolyse cyclic (c)AMP in rat and rabbit ventricular myocardium has been compared. The PDE activity of rabbit, but not rat, cardiac homogenate and supernatant fraction was potentiated by Ca2+/calmodulin and attenuated by cGMP. Both rabbit and rat ventricular myocardium were shown to have a membrane bound PDE. However, rabbit membrane-bound PDE was inhibited by cGMP and low concentrations of milrinone (IC50 2.7 microM). In contrast, rat membrane-bound PDE was not inhibited by either cGMP or low concentrations of milrinone (IC50 19 microM), but it was potently inhibited by rolipram (IC50 2.2 microM). Thus, in rabbit the particulate PDE is milrinone sensitive (PDE III) whilst in rat it is the rolipram sensitive (PDE IV) isoenzyme. There are clearly species differences in the intracellular localization and relative activities of PDE isoenzymes in cardiac tissue. This may explain the species differences already found in the activity of selective PDE isoenzyme inhibitors as inotropic agents. 相似文献
34.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
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38.
S Jenkins B Arroll S Hawken R Nicholson 《The British journal of general practice》1997,47(415):107-108
An essential mode of contact between general practitioners (GPs) and hospital staff is the referral letter. This must be clear and concise with sufficient information to aid the GP, the consultant and the patient. In order to ensure this, a proposal was made for the use of a structured or standardized referral letter: a form letter. This report shows that form letters were shorter than typed letters. Form letters were also proven to contain more information than nonform letters. 相似文献
39.
M L Nicholson P S Veitch P K Donnelly A J Flower P R Bell 《Transplantation proceedings》1990,22(4):1811-1812
40.
Dipyridamole alone or combined with low-dose acetylsalicylic acid inhibits platelet aggregation in human whole blood ex vivo. 总被引:1,自引:1,他引:0
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J R Hughes S G Bowes A L Leeman C J O''''Neill A A Deshmukh P W Nicholson S M Dobbs R J Dobbs 《British journal of clinical pharmacology》1990,29(2):179-186
1. In a randomized, double-blind trial we compared the inhibition of the platelet-vessel wall interactions in whole blood ex vivo. There were four groups of 24 healthy volunteers each of whom were treated orally for 3.5 days with either 200 mg dipyridamole (sustained release preparation), 25 mg acetylsalicylic acid, both drugs combined or placebo twice daily. 2. The mean area of all platelets/aggregates was reduced by 6.2% +/- 4.2% (+/- s.e. mean) by placebo (n = 23), 19.8% +/- 6.7% by dipyridamole (n = 22), 53.7% +/- 4.9% by acetylsalicylic acid (n = 23) and 71.4% +/- 3.7% by the combination of both drugs (n = 24), when compared with total inhibition of aggregation by EGTA. Thus, low-dose acetylsalicylic acid inhibited aggregation (P less than 0.001). 3. Dipyridamole reduced the size of platelet aggregates (P less than 0.01, two-fold analysis of variance). The reduction was correlated with the individual dipyridamole plasma levels (P less than 0.05, analysis of covariance). The subgroup of large and very large thrombi being formed was also reduced by dipyridamole (P less than 0.05). 4. This ex vivo study demonstrates that dipyridamole alone inhibits formation of thrombi on subendothelial matrix and enhances the inhibitory effect of low dose acetylsalicylic acid in this model of thrombosis. 相似文献