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S Flor D Guay J Opsahl K Tack G Matzke 《International journal of clinical pharmacology research》1991,11(3):115-121
The pharmacokinetics of the new fluoroquinolone antimicrobial ofloxacin were studied in 18 subjects with normal renal function or varying degrees of renal impairment, including patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis. Apparent total body and renal clearances declined and elimination half-life increased with decreasing creatinine clearance. CAPD and haemodialysis removed clinically insignificant fractions of ofloxacin body burden over the study period (6-15% and 9-11% of the dose, respectively). The apparent volume of distribution, peak concentration, time to peak concentration, and non-renal clearance were not altered significantly by renal insufficiency. An extended dosing interval of 24-48 h is recommended, depending upon the degree of renal impairment, when creatinine clearance falls below 50 mL/min. In addition, supplemental doses would not appear to be necessary during CAPD and following haemodialysis. 相似文献
4.
P L Westesson R H Tallents R W Katzberg J A Guay 《AJNR. American journal of neuroradiology》1994,15(5):991
PURPOSETo assess the relationship between mandibular asymmetry and disorders of the temporomandibular joint.METHODSWe used advanced imaging of the temporomandibular joint to distinguish different causes of mandibular asymmetry. MR imaging and arthrography were applied to the temporomandibular joints of 11 patients presenting with mandibular asymmetry.RESULTSCondyle hyperplasia was identified as the cause of the asymmetry in 5 patients. In the other 6 patients the mandibular condyle was normal on the long side, but the short side of the face demonstrated a small condyle head, short condyle neck associated with disk displacement, internal derangement, and degenerative joint disease of the temporomandibular joint.CONCLUSIONSThese observations suggest that both condyle hyperplasia on the long side of the mandible and disk displacement and degenerative joint disease of the temporomandibular joint on the short side can cause mandibular asymmetry. It was concluded that MR imaging or arthrography can be valuable for understanding the cause of mandibular asymmetry and be effective in treatment planning. 相似文献
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G TamizhMani J.P Dodelet D Guay L Dignard-Bailey 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1998,444(1):121-125
Four platinum-based catalysts with different catalytic activity for the oxygen reduction reaction have been prepared and tested in polymer fuel cells (PFCs) and in half-cells with H2SO4 and HF electrolytes. The activity results of PFCs at 0.9 V versus RHE (reversible hydrogen electrode) can be mimicked in parallel by the results obtained in HF electrolyte but not by the results obtained in H2SO4 electrolyte. This paper concludes that the pre-screening of a huge number of Pt-based catalysts for the selection of potential catalysts for the PFCs can be carried out by a rapid half-cell technique with a non-adsorbing electrolyte such as HF. 相似文献
7.
Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk 下载免费PDF全文
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
8.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
9.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献
10.
Shumikhina S Guay J Duret F Molotchnikoff S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2004,158(2):223-232
Synchronization of neuronal activity has been proposed as a binding mechanism for integration of image properties into one coherent percept. In the present study, we investigated the contextual modulation of synchronization to random dot patterns. Coherent motion of random dots evoked well synchronized responses in area 17 of anaesthetized cats when the stimulus was presented in the compound receptive field of recorded sites. Gradually changing the directional coherence of random dots in the surround while maintaining fully coherent motion of the stimulus in the receptive field significantly suppressed synchronization of neuronal activity for some stimulus conditions. However, usually one or two peaks of increased synchronization were found in the surround coherence tuning curves with low (8–12%) and/or moderate (25–50%) coherence in the surround. At the population level, synchronization was significantly depressed with incoherent motion in the receptive field and when both the surround and the receptive field were jointly stimulated with 0% coherence. The intriguing finding was the discovery of two distinct groups of cells with opposite synchronization changes dependent on the presence or absence of significant synchronization in their spontaneous activity. The latter group of neurons showed peaks of increased synchronization with lower surround coherence, thus probably being more sensitive to the direction of the surround motion. Overall, our findings support the notion that binding of stimulus properties can be achieved by synchronized activity of cortical cells. However, our findings go further than the original hypothesis of feature binding by synchrony to show that synchronization of cortical activity may be directly related to the decision making processes, which in turn are related to the threshold of perception of coherent motion. 相似文献