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951.
Breast cancer is one of the most frequent malignancies in the world. Available staging procedures to detect breast cancer are bone scan, chest X-ray, liver ultrasonography, computerized tomography, estimation of tumor markers like carbohydrate antigen (CA15-3) and carcino embryonic antigen. These procedures are expensive and may not be required in all cases. Out of 70 patients studied, 55 had normal CA15-3 and 15 had elevated levels of Ca15-3. Eight (14.5%) of the 55 patients with normal CA15-3 had abnormal bone scan. Fifteen patients had CA15-3 levels above the normal range and among these 9 (60%) had abnormal bone scan. While prime facie it would appear that a high level of CA15-3 correlate with abnormal bone scan, it is also true that the numbers are small at present and conclusions about the validity of CA15-3 as marker of bone metastasis may be premature.  相似文献   
952.
953.
The Antarctic continent on the planet Earth is full of environmental extremes. It is considered as natural stress model. Therefore, the present study examined the effect of harsh environment on the certain salivary markers of 28th Indian Antarctic expeditioners. Thirty healthy men and women (median age 36 year; range 22–61 year) participated in this study. Parameters measured were salivary IgA (SIgA), IgM (SIgM), TGF-β and cortisol level at three different time points: (I) before leaving India on 26th October 2008 for base line level; (II) after 1 month on-board journey on 31st January 2009 in Southern Ocean and (III) after 1 month staying at Maitri, Antarctica on 3rd March 2009. Our observation indicated that Ship borne journey and Antarctic environment increased the SIgA levels while that of SIgM level was not altered on-board but decreased by staying for 1 month at Antarctica. No significant alteration was found in the TGF-β and cortisol level at any point of time. The present study concluded that ship borne journey and Antarctic environment may induce the SIgA level while SIgM level decreased in environmental extremes of Antarctica.  相似文献   
954.
955.
Quantifying countermovement jump (CMJ) and landing knee flexion angle is important for performance and injury risk assessment. The purpose of the study was to compare electrogoniometer (El-Gon)- and video-derived CMJ and landing knee flexion angle. Twenty-two adults performed three CMJs while knee flexion angle was simultaneously assessed using an El-Gon and video. The average systematic offset (RMSE) of the El-Gon-derived knee flexion angle throughout the entire movement was 7.03°?±?2.69°. Excellent reliability was demonstrated by the El-Gon (ICCavg?=?0.92). Countermovement knee flexion angle, maximum landing knee flexion angle and flexion angle at maximum vertical ground reaction force were 12.0°, 10.9°, and 5.7° higher, respectively, when assessed using El-Gon (p?<?0.001), compared to video. Errors between instruments are likely due to El-Gon crosstalk, misalignment and/or axis determination. The El-Gon is a cost-effective and time-efficient alternative to video analysis for the assessment of knee flexion angle if the error is accounted for and the sensor is precisely attached.  相似文献   
956.
To examine the development of look duration as a function of age and stimulus type, 14- to 52-week-old infants were shown static and dynamic versions of faces, Sesame Street material, and achromatic patterns for 20 s of accumulated looking. Heart rate was recorded during looking and parsed into stimulus orienting, sustained attention, and attention termination phases. Infants' peak look durations indicated that prior to 26 weeks there was a linear decrease with age for all stimuli. Older infants' look durations continued to decline for patterns but increased for Sesame Street and faces. Measures of heart rate change during sustained attention and the proportion of time spent in each phase of attention confirmed infants' greater engagement with the more complex stimuli.  相似文献   
957.
Children at risk for early reading difficulties were identified on entry into kindergarten, and half of these children received small-group intervention two to three times a week during their kindergarten year. The other half received whatever remedial assistance was offered by their home schools. These children were again assessed at the beginning of first grade, and those who continued to have difficulties in reading received either one-to-one daily tutoring offered by project teachers from the beginning to the end of first grade or whatever remedial assistance was offered by their home schools over the same time period. All target children were periodically assessed through the end of third grade. Results suggest that either kindergarten intervention alone or kindergarten intervention combined with first-grade intervention are both useful vehicles for preventing early and long-term reading difficulties in most at-risk children.  相似文献   
958.
Empirical data on the development of interaction, communication, and language in deafblind children is very rare. To fill this gap, a case study was conducted in which the interaction between a teacher and a deafblind boy age 3 years 4 months was analyzed. Sequential analysis of their interaction confirmed some general clinical impressions about interaction with deafblind children, and provided the basis for suggestions on how the interaction pattern might be changed.  相似文献   
959.
The moulding of the future of a nation depends on the teachers and the education they provide in schools. Research evidence from the US. National Assessment of Educational Progress (NAEP) confirms this to be the case. Quantitative analysis of data indicates that measures associated with pre-service teacher preparation are by far the strongest correlates of student achievement (Darling-Hammond 2000). The research report of Wilson, Floden, and Ferrini-Mundy (2001) also suggests a strong relationship between teacher preparation and teacher effectiveness. Other research studies similarly indicate that differences in teacher quality are the most crucial for student achievement when compared with variables such as class size, streaming, or the amount of homework (Anderson & Helms 2001; Mendro 1998; Powell & Anderson 2002; Rivkin, Hanushek & Kain 2001; Saunders & Horn 1994; Strong & Tucker 2000) as possible contributory factors. In the pursuit of improved student achievement, we therefore need to examine seriously the role of teacher variables, ranging from teacher qualifications and their subject matter knowledge, to what motivates them to take up teaching as a career and as a consequence, how they teach in classrooms.  相似文献   
960.
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