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1.
2.
Clonidine prolongs canine tetracaine spinal anaesthesia 总被引:1,自引:0,他引:1
M D Bedder R Kozody R J Palahniuk M O Cumming W R Pucci 《Canadian Anaesthetists' Society journal》1986,33(5):591-596
Using a randomized blind cross-over design, the comparative efficacy of clonidine in prolonging tetracaine spinal anaesthesia was studied in six mongrel dogs. Lumbar subarachnoid injections (1 ml) of: tetracaine 4 mg with clonidine 150 micrograms, tetracaine 4 mg with epinephrine 200 micrograms, tetracaine 4 mg, clonidine 150 micrograms, epinephrine 200 micrograms, and five per cent dextrose in H2O (vehicle) were administered randomly to each animal at 5-7 day intervals. Subarachnoid tetracaine produced a motor blockade of 186 +/- 58 (mean +/- SEM) min. Both clonidine and epinephrine produced a similar prolongation of tetracaine motor blockade, 135 per cent (p less than 0.01) and 116 per cent (p less than 0.05) respectively, compared with tetracaine alone. No motor blockade was observed in dogs receiving clonidine, epinephrine or five per cent dextrose in H2O. The addition of clonidine to tetracaine spinal anaesthesia produced a significant increase in duration of sensory blockade, 56 per cent (p less than 0.01) and 107 per cent (p less than 0.01) respectively, when compared to tetracaine with and without epinephrine. Subarachnoid clonidine alone produced a sensory blockade of 76 +/- 17 minutes, while only one animal receiving subarachnoid epinephrine had a sensory blockade (40 minutes). No neurologic deficits were observed in any of the animals. The study concludes that during spinal anaesthesia with tetracaine in dogs, clonidine is as effective as epinephrine in prolonging motor blockade, but is more effective in prolonging sensory blockade. 相似文献
3.
Is antibiotic prophylaxis necessary for routine urodynamic investigations? A controlled study in 100 patients 总被引:1,自引:0,他引:1
The value of a prophylactic antibiotic before a routine cystometrogram has been assessed in a controlled trial of 100 patients. The infection rate was low and not statistically different in both groups. Subsequent symptoms of dysuria and haematuria had a mechanical aetiology. 相似文献
4.
P. Cumming T. K. Venkatachalam S. Rajagopal M. Diksic A. Gjedde 《Synapse (New York, N.Y.)》1994,17(2):125-128
The blood-brain permeabilities of L-[3H]tyrosine and the tyrosine hydroxylase (TH) inhibitor β-[14C]methyl-para-tyrosine ([14C]AMPT) were determined in rat striatum, a brain region rich in TH activity, and in other brain regions containing relatively little TH activity. In striatum, the unidirectional clearance rate (K1) for L-[3H]tyrosine (6.2 ml hg- ?1 min?1) was significantly greater than the rates for L-[14C]AMPT (2.8 ml hg?1 min?1) and D-[14C]AMPT (0.8 ml hg?1 min?1). The apparent volume of distribution (Vf) for L-[14C]AMPT in striatum (72.5 ± 4.0 ml hg-1) did not differ from the Vf in other brain regions. The homogeneous distribution of L-[14C]AMPT in rat brain indicates that labeled AMPT is unsuitable for the study of TH in vivo by quantitative autoradiography. © 1994 Wiley-Liss, Inc. 相似文献
5.
Crown of microfilaments in the extending cytoplasmic processes of medulloblastoma glial progenitors.
B L Maria R Cumming L Sukhu 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1992,19(1):23-33
Microfilaments and microtubules play a part in the extension of neuronal processes but their roles in the formation of glial processes have not yet been determined. The objectives of this study were to determine the organization of microfilaments in differentiating glial progenitors (RB2 cells) and to study the effects of microfilament or microtubule disruption on process extension. Intense F-actin staining (crown of microfilaments) was observed at the leading edge of a small extending conical tip in differentiating RB2 cells, but was absent in process-bearing TE671 rhabdomyosarcoma cells. No significant difference was noted in the mean number of TE671 cells with processes treated with a microfilament disrupter from that of similarly treated controls. In contrast, a significant difference was noted in the mean number of RB2 cells with processes after microfilament disruption treatment from that of similarly treated controls. Microtubule disruption arrested extension and caused process retraction in both cell types. The results of this study demonstrate that microtubules play an equally important part in the extension and stabilization of the RB2 and TE671 processes. Moreover, the crown of microfilaments concentrated in the glial RB2 process (and not in the TE671 process) may be critical to its extension during differentiation. 相似文献
6.
A multi-centre phase two study of intravesical epirubicin in the treatment of superficial bladder tumour 总被引:1,自引:0,他引:1
Epirubicin (4'-epi-adriamycin) was used in the treatment of widespread superficial carcinoma of the bladder. Thirty-seven patients received 50 mg in 50 ml of saline retained for 60 min. There was an overall response rate of 59% but this was of short duration. Thirty percent of patients progressed despite therapy. Therapy was associated with an incidence of side effects which necessitated therapy withdrawal in 12 (32.4%) patients. It is concluded that epirubicin, in the dose used in this study, cannot be recommended for routine intravesical chemotherapy and that further studies, at a reduced dosage, are necessary to evaluate this agent. 相似文献
7.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
8.
9.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
10.
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