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81.
Sensory Properties of Fats and Fat Replacements 总被引:2,自引:0,他引:2
Adam Drewnowski Ph.D. 《Nutrition reviews》1992,50(4):17-20
82.
Karen Rosendahl Stein Magnus Aukland Kari Fosse 《European Radiology Supplements》2004,14(4):L138-L145
Appendicitis is the commonest acute surgical emergency of childhood, and occurs in approximately 2–4 per 1000 infants. It is usually seen in infants older than 5 years but can occur at any age. Atypical clinical findings are seen in 30–50% of children, especially the younger ones, and often leads to a delayed diagnosis. Preoperative clinical assessment alone has yielded an accuracy ranging between 70 and 90% but is associated with a normal appendectomy rate of 13–25%. Preoperative imaging using the graded compression US technique and/or different helical CT techniques has been able to reduce this rate to 3–7% without an increase in perforation rate. An extensive review of the literature revealed several papers examining the accuracy of different imaging modalities and strategies of acute appendicitis in children. The reported sensitivity of US varied between 87 and 95%, vs 95–97% for helical CT, while the specificity ranged between 85 and 98% for US and 94 and 97% for helical CT. Only one truly randomised study was found, showing that compared with US alone, a combination of US and helical CT increased the sensitivity from 86 to 99%, while the specificity decreased from 95 to 89%. We conclude that imaging should be performed in all children with suspected appendicitis and that US should be the initial procedure with CT as a complementary tool. 相似文献
83.
84.
Menahem Neuman Boris Friedman Avi Stein A. Ami Sidi Alexander Tsivian 《Gynecological surgery》2007,4(3):175-178
The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral
sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The
study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in
one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second
group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative
diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months.
The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly
younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration,
intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either
group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and
5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients
and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients,
while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of
the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT
procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective
in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than
previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures,
less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however,
had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions
can be drawn on the superiority of either of these two operative techniques. 相似文献
85.
Chris Chase Robert F Dougherty Nicola Ray Susan Fowler John Stein 《Optometry and vision science》2007,84(3):229-236
PURPOSE: Many behavioral studies have found impaired perception of dynamic visual stimuli in dyslexia and several neuroimaging studies have found reduced activation of the human motion area MT+ in dyslexia. These results are often interpreted as a magnocellular (MC) deficit in dyslexia. It has also been claimed that colored filters can help dyslexics to read. One defining feature of the MC-pathway is a greater weight for L-cone input than M-cone input, and at most very weak S-cone input. We measured the subjective speed matches between L-, M-, and S-cone isolating stimuli in good and poor readers. METHODS: Subjects performed a speed-matching task with drifting cone-isolating stimuli to find the point of subjective equality between two drifting patterns. Such a task is known to activate cortical area MT+, presumably via the MC-pathway. RESULTS: L- to M-cone speed-match ratios were negatively correlated with single-word (r=-0.46) and irregular-word reading (r=-0.56) but not with non-word reading. CONCLUSIONS: Results suggest that relative L-cone sensitivity within the MC-pathway may limit orthographic reading performance. 相似文献
86.
87.
I Dormehl R Burow N Hugo M Maree C Van Zandwijk C Van Vuuren W E Adam 《Nuclear medicine communications》1987,8(10):805-813
Phase analysis of data from radionuclide ventriculograms is known to provide space-time information on the mechanical emptying of pixels located in the ventricular regions. It could therefore perhaps be useful for detecting abnormal sequences of contraction of the ventricles as well as to localize sites of premature electromechanical action. The phase programme used in this investigation is designed to trace the electromechanical action of the ventricles from colour-coded phase images (first harmonic Fourier transform), not only visually from a cinematic representation, but particularly from a data output of x, y coordinates and phase angles of sites chosen as they empty in the ventricular regions. Six healthy baboons were subjected to conventional radionuclide ventriculography, performed hourly for the duration of 11 h under anaesthesia. The programme was used by two independent observers to map the progression of emptying for each of the thus acquired 66 left ventricular phase images. The interobserver reliability and the accuracy achieved in mapping normal contraction patterns was found to be good. Abnormalities which appeared during the prolonged anaesthesia and which were confirmed with 12 lead electrocardiography were likewise detected consistently. 相似文献
88.
Multiple congenital supratentorial intracerebral cysts occurred in a newborn infant. The cysts, of varying size, content and lining, occupied the cerebral hemispheres. They formed a mosaic pattern on CT scan and left no trace of a recognisable ventricular system. Multiple surgical procedures were performed during the first year of life, and at one year the child was very well and asymptomatic, with two functioning shunts. 相似文献
89.
Factors that determine the magnitude and time course of human H-reflexes in locomotion 总被引:7,自引:0,他引:7
The soleus H-reflex amplitude is deeply modulated during locomotion in humans (Capaday and Stein, 1986). Moreover, at a constant stimulus intensity, the slope of the relationship between the amplitude of the soleus H-reflex and the background electromyogram (EMG) changes with different locomotor tasks (Capaday and Stein, 1987a). Two further aspects are studied here. First, we recorded the reflex during overlapping speeds of walking (2.0-7.5 km/hr) and running (5-9 km/hr) to determine whether the speed, the motor output, or the form of locomotion was most important in setting the slope of this relationship between H-reflex and background EMG. Second, we determined the time course of change in the H-reflex amplitude and the possible site of action for the reflex depression during the transition from standing to walking. The primary determinant of the slope was found to be the form of locomotion. The differences between running and walking could not be explained entirely by either movement speed or motor output. For walking, the slope varied inversely with the speed and the motor output of locomotion. This compensation in slope as a function of motor output may prevent saturation of the motoneuron pool. The appropriate reflex amplitudes for a particular locomotor pattern are activated rapidly and completely within a reaction time, and simultaneously with the activation of muscle activity for the initiation of walking. Mechanisms for the rapid change seen during the initiation of locomotion most likely act presynaptically on the muscle spindle afferents. The time course and magnitude of this change are correlated with the activity of the tibialis anterior muscle. 相似文献
90.