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61.
Prenatal ultrasound diagnosis of clubfoot 总被引:1,自引:0,他引:1
Five cases of congenital clubfoot diagnosed prenatally by ultrasound are reported. The incidence of clubfoot may be higher within an affected family and may be associated with other structural anomalies or chromosomal abnormalities. Identifying a clubfoot in utero should therefore alert the sonographer that other anomalies may be present and should lead to a detailed structural survey. 相似文献
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Rosen BR; Fleming DM; Kushner DC; Zaner KS; Buxton RB; Bennet WP; Wismer GL; Brady TJ 《Radiology》1988,169(3):799
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Greif WL; Buxton RB; Lauffer RB; Saini S; Stark DD; Wedeen VJ; Rosen BR; Brady TJ 《Radiology》1985,157(2):461-466
Paramagnetic agents enhance contrast between tissues in magnetic resonance (MR) imaging by altering tissue relaxation times. The effect of these changes on MR image intensity depends in part on the choice of operator-controlled pulse sequence parameters. With the newly described paramagnetic hepatobiliary contrast agent, iron(III) ethylenebis-(2-hydroxyphenylglycine), Fe(EHPG)-, an in vivo experimental analysis of pulse sequence optimization was performed on the rat. We compared the enhancement of the liver divided by background noise, EL/N, of standard inversion-recovery (IR) and spin-echo (SE) T1-weighted pulse sequences and several pulse sequences theoretically predicted to have improved EL/N. Optimization of the echo time (TE = TEmin) gave a substantial (greater than 60%) increase in EL/N over the standard IR and SE pulse sequences. Images obtained with optimized repetition rate and inversion time gave only a slight additional improvement. Within the uncertainties of our relaxation measurements, the measured changes in EL/N with pulse sequence optimization corresponded well with theoretical predictions. With the experimental and theoretical data, the importance of using a short echo time to obtain maximal T1 contrast in contrast-enhanced MR imaging and the relative merits of optimized SE versus IR pulse sequences for contrast-enhanced MR imaging are discussed. 相似文献
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In past there have been many medicinal plants, which have been used in traditional medicines for their antidiabetic properties without any scientific support and pharmacological evidence. The aqueous extract of Murraya koenigii leaves has been taken to evaluate the hypoglycemic activity in normal and alloxan induced diabetic rabbits. This plant is promising as it is widely and regularly used as a spice for food flavoring and as such it appears to be without any side effects and toxicity. Adequate characterization of hypoglycemic activity of aqueous extract has not been yet done, as no such reports are available in the literature though the activity is reported. The scientific evaluation of its hypoglycemic activity was, therefore, explored and also compared with the effect of a standard hypoglycemic drug, tolbutamide. A single oral administration of variable dose levels (200, 300 and 400 mg/kg) of aqueous extract led to lowering of blood glucose level in normal as well as in diabetic rabbits. The maximum fall of 14.68% in normal and 27.96% in mild diabetic was observed after 4 h of oral administration of 300 mg/kg. The same dose also showed a marked improvement in glucose tolerance of 46.25% in sub-diabetic (AR) and 38.5% in mild diabetic rabbits in glucose tolerance test after 2 h. The findings from this study suggest that the aqueous extract of these leaves may be prescribed as adjunct to dietary therapy and drug treatment for controlling diabetes mellitus. 相似文献