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991.
992.
We have measured systolic and diastolic blood pressure and excretions of sodium, potassium, calcium and magnesium in groups of about 50 8- and 9-year-old boys from 19 European centres using standardized methods for the measurement of blood pressure and collection of urine, and by carrying out all analyses in one laboratory. Weight, height, pulse rate and environmental temperature were also studied. Mean systolic blood pressure ranged from 91 to 105 mm Hg and diastolic blood pressure from 51 to 66 mm Hg. Mean 24-h excretion of sodium was between 91 and 146 mmol/d, that of potassium between 29 and 60 mmol/d, that of calcium between 1.5 and 2.6 mmol/d and that of magnesium between 2.7 and 4.2 mmol/d. Mean sodium excretion tended to be lower and potassium excretion tended to be higher in the boys from the north-western parts of Europe. Relations between either systolic or diastolic blood pressure and electrolyte excretions were generally weak or absent. Most remarkable is that only the association between mean diastolic blood pressure and 24-h magnesium excretion (partial regression coefficient (b +/- s.e., -5.04 +/- 2.08 mm Hg/mmol/d) was statistically significant after adjusting for differences in creatinine excretion and environmental temperature. Mean systolic blood pressure was not significantly related with any of the variables measured. The partial regression coefficient (b +/- s.e.) for diastolic blood pressure on weight was 0.186 +/- 0.062 mm Hg/kg, on height 0.165 +/- 0.056 mm Hg/cm, on pulse rate 0.364 +/- 0.100 mm Hg/beats per min and on outside temperature -0.25 +/- 0.07 mm Hg/degrees C.  相似文献   
993.
This report presents for the first time the results of carrying out epikeratophakia with tissue lathed at room temperature. Using an experimental model of epikeratophakia in the rabbit, we evaluated tissue handling techniques for the preparation of donor lenticules. Details of the technique are described and the in-vivo and histopathological findings reported.  相似文献   
994.
995.
996.
A heterocentric aplanatic contact of one piece has been designed for optimal efficiency of laser surgery for ALT and YLT in the angle of the anterior chamber.  相似文献   
997.
Since more than a century ago, temperatures above 40 degrees C have been known to be effective in cancer treatment. Since that time numerous studies have documented that hyperthermia alone causes tumor regression and that the therapeutic effect depends on the amount and duration of heat delivered to a malignant tumor. However, after it was shown that heat combined with irradiation or chemotherapy potentiates the effect of hyperthermia, both thermoradiotherapy and thermochemotherapy were applied in experimental and clinical studies in several medical specialties. In ophthalmic oncology both retinoblastoma and uveal melanoma are treated by irradiation combined with local hyperthermia. In the present paper the use of ultrasound and microwave energy as locally applicable heat sources in intraocular malignancies is described and their suitability discussed. As is the case with malignant skin tumors and malignant tumors of the gastrointestinal and urogenital systems, malignant ocular tumors are accessible to externally applied heat and can thus be treated well by ultrasound and microwave hyperthermia. On the basis of experimental and clinical results gained with both ultrasound and microwave energy the advantages and drawbacks of these two technical modalities in intraocular tumor therapy are pointed out.  相似文献   
998.
Two methods of measuring lacrimation with a cotton thread and fluorescein have been described hitherto. Method 3 is intended for testing lacrimal flow in wearers of soft contact lenses. Fluorescent paper can be used to facilitate the measuring procedure. The method has been shown to be reliable in numerous control tests on subjects with normal eyes and in comparisons with the authors' methods 1 and 2. With the test, values of less than 5 mm indicate severe lacrimal deficiencies.  相似文献   
999.
Recently introduced prosthetic socket designs for the above-knee amputee (AKA) feature a narrow medial-lateral dimension and emphasize maintenance of the residual limb in full physiologic adduction. Quantitative data on the effect of frontal plane limb position on the isometric hip abductor strength of ten otherwise healthy AKAs were obtained in the standing position. Residual limb isometric and isokinetic abductor strength was also measured and compared with that of the intact limb and with that of ten healthy age-, sex-, and height-matched control subjects using an identical technique. The testing hardware consisted of a modified Cybex II Isokinetic Dynamometer with a custom-made pelvis and trunk stabilizing device. Anthropometric measurements were taken. Results showed an essentially linear increase in residual limb abduction strength with progressive adduction from 30 degrees abduction to 16 degrees adduction. The average increase in abduction torque was .97% (range .29 to 1.5) of the peak neutral position strength per degree of change in femur angle when corrected for the effect of gravity. Similar strength increases with adduction of the femur were found for intact and control limbs. Mean residual limb isometric abduction torque measured 30% less than the intact limb value (p = .0018). The difference between the intact and the control limb mean isometric abduction torques was less than 1%. Isokinetic testing was technically more difficult than isometric testing but revealed similar weakness of the residual limb abductors when compared to the intact and control limbs.  相似文献   
1000.
Pharmacokinetics may be utilized as a tool in the drug development process, either with respect to therapeutics or in allowing a drug's disposition characteristics to be defined. If two drugs of the same class have a similar dose-efficacy profile, then the favourable/unfavourable balance of the pharmacokinetic characteristics of the drugs may determine the drug of choice. Pantoprazole, a proton pump inhibitor, appears to meet the above criteria and has been found to exhibit reliable, predictable pharmacokinetic characteristics as opposed to other members of the class. The pharmacokinetics of pantoprazole over a range of intravenous and oral doses are described in healthy volunteers and are compared with values obtained for omeprazole. Studies in patients with severe cirrhosis, renal failure, and in the elderly are also described as well as potential interactions due to food and five other drugs.  相似文献   
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