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51.
Age-related postural deficits elicit compensatory mechanisms such as ankle dorsiflexion in the elderly. To gain further insight into this problem, the ability to match an ankle angle during quiet stance was studied in 12 elderly and 12 young subjects. Following an initial single limb angular perturbation presented in the ±4° range, a subject had to return a tilt platform to level, as determined by the nonperturbed limb. Elderly subjects exhibited significant positive (0.9°) over-shoot of the level position, in contrast to young subjects who matched ankle angle with a mean error of −0.1°. The elderly group also exhibited an increase in positioning error for angular displacements in the range between −1 and +1°. The results document age-related postural changes in ankle positioning which might affect postural stability in older adults.  相似文献   
52.
Multiple myeloma: evaluation by CT   总被引:3,自引:0,他引:3  
Schreiman  JS; McLeod  RA; Kyle  RA; Beabout  JW 《Radiology》1985,154(2):483-486
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.  相似文献   
53.
54.
Cooper  KL; Beabout  JW; McLeod  RA 《Radiology》1985,157(1):15-17
Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.  相似文献   
55.
56.
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
57.
Forty elderly patients with asthma or chronic obstructive pulmonary disorder (COPD) were compared to a comparison group of forty age-matched healthy volunteers on a range of measures of cognitive performance, and levels of arterial haemoglobin oxygen saturation recorded. Members of the patient group were found to have significantly lower oxygen saturation compared to the comparison group, and performed significantly poorer on tests of delayed word recall and serial subtractions, but not on other tasks. Correlational analysis between participants' oxygen saturation levels and test scores across the whole sample indicated significant positive relationships existed for the digit symbol substitution and serial subtractions tasks. The results are discussed in terms of cerebral oxygen delivery, glucose metabolism, age related cognitive decline, and relative task demands.  相似文献   
58.
We have previously shown that users of oral contraceptive (OC) medications exhibit increased plasma levels of angiotensin II (Ang II) with only modest hemodynamic consequences, suggesting estrogen-mediated Ang II type 1 (AT(1)) receptor downregulation. Accordingly, in 10 women who were OC users and 10 women who, as OC nonusers, served as controls, all mean age 26 +/- 1 yr, we examined the renal and peripheral hemodynamic response to graded Ang II infusion, plasma and urine cyclic guanosine monophosphate (cGMP) levels as a surrogate marker for AT(1) and/or AT(2) receptor-mediated activation of the nitric oxide pathway, and AT(1) receptor expression in skin biopsies. The OC nonusers were studied during the follicular and luteal phases of the menstrual cycle, whereas OC users were studied once during the 21-d medication phase. Subjects ingested a controlled sodium diet for 7 d before each study. Renal hemodynamic function was assessed using standard inulin and p-aminohippurate clearance techniques. AT(1) receptor mRNA levels in skin biopsy samples were assessed using a real-time PCR protocol. In response to graded Ang II infusion, OC users exhibited renal and peripheral hemodynamic responses that were augmented compared with those of OC nonusers, in conjunction with evidence of increased tissue AT(1) receptor expression. Plasma cGMP levels and 24-h urinary cGMP excretion did not differ. These data suggest that, contrary to our original hypothesis, OC use does not appear to be associated with AT(1) receptor downregulation. The factor protecting OC users from the hemodynamic impact of increased Ang II levels remains elusive.  相似文献   
59.
Foex  P; Sear  JW 《CEACCP》2004,4(3):71-75
Arterial hypertension is a major cause of morbidity and mortalitybecause of its association with coronary heart disease, cerebrovasculardisease and renal disease. The extent of target organ involvement(i.e. heart, brain and kidneys) determines outcome. North Americanstudies have shown that hypertension is a major contributorto 500 000 strokes (250 000 deaths) and 1 000 000 myocardialinfarctions (500 000 deaths) per annum.  相似文献   
60.
It has previously been demonstrated in separate studies that single doses of Ginkgo biloba, Panax ginseng, and a combination of the two extracts can improve different aspects of cognitive performance in healthy young volunteers. The present study directly compared the effects of single doses of G. biloba, ginseng, and a product combining the two on aspects of mood and cognitive performance in the same cohort of healthy, young adult volunteers. The study followed a randomised placebo-controlled, double-blind, balanced, cross-over design. Twenty participants received 360 mg of ginkgo, 400 mg of ginseng, 960 mg of a product combining the two extracts, and a matching placebo. Treatment order was dictated by random allocation to a Latin square, with a 7-day wash-out period between treatments. Cognitive testing comprised completion of the Cognitive Drug Research (CDR) computerised assessment battery and two serial subtraction mental arithmetic tasks. Mood was assessed with Bond-Lader visual analogue scales. Following a baseline cognitive assessment, further test sessions took place 1, 2.5, 4, and 6 h after the day's treatment was taken. The results largely supported previous findings. All three treatments were associated with improved secondary memory performance on the CDR battery, with the ginseng condition evincing some improvement in the speed of performing memory tasks and in the accuracy of attentional tasks. Following ginkgo and the ginkgo/ginseng combination performance of both the Serial Threes and Serial Sevens, subtraction tasks was also improved at the later testing sessions. No modulation of the speed of performing attention tasks was evident. Improvements in self-rated mood was also found following ginkgo and to a lesser extent the combination product.  相似文献   
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