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211.
To establish whether additional therapy with 3-hydroxy-3-methylglutaryl (HMG) coenzyme A (CoA) reductase inhibitors enhances the low-density lipoprotein (LDL) cholesterol lowering effect of LDL apheresis with immunoadsorption in the treatment of patients with familial heterozygous hypercholesterolemia and coronary artery disease we studied eight patients initially on immunoadsorption therapy alone for 3 years. The adding of HMG CoA reductase inhibitors decreased pretreatment LDL cholesterol from 6.76 +/- 0.98 to 4.97 +/- 0.98 mmol/l and posttreatment LDL cholesterol from 2.33 +/- 0.80 to 1.94 +/- 0.67 mmol/l and increased pre- and posttreatment high-density lipoprotein (HDL) cholesterol by 0.08 and 0.13 mmol/l respectively. The LDL/HDL ratio was reduced from 4.0 to 2.8 (prior to any therapy the ratio was 13.4). The increase in LDL cholesterol between weekly treatments was less steep under the combined therapy. At the same time the treated plasma volume during LDL apheresis could be decreased from 5070 +/- 960 to 4370 +/- 1200 ml. We conclude that in patients with severe familial heterozygous hypercholesterolemia LDL apheresis should be combined with HMG CoA reductase inhibitors. 相似文献
212.
213.
The two best-recognized stimuli for calcitriol production are parathyroid hormone (PTH) and dietary phosphorus deprivation. We studied the relative importance of these two stimuli in subjects with moderate chronic renal failure (MCRF). We recruited 10 subjects with MCRF aged 49 +/- 13 years (mean +/- SD) and having a creatinine clearance rate of 31 +/- 24 mL/min. After an overnight fast, they received 400 IU human PTH 1-34 subcutaneously, and blood and urine samples were collected over the subsequent 24 hours. They then took aluminum hydroxide 30 mmol/d for 2 months to reduce gut phosphorus absorption, at the end of which the PTH stimulation test was repeated. Responses were compared with those obtained in 11 normal subjects aged 44 +/- 16 years and having a creatinine clearance rate of 102 +/- 37 mL/min who were only studied while on their normal diet. Following PTH stimulation in the normal subjects but not the MCRF subjects, there was a significant increase in plasma calcium and calcitriol levels, with a significant decrease in renal phosphorus threshold. In both groups there was a similar and significant increase in urine cyclic adenosine monophosphate (cAMP) levels. Following restriction of absorption of dietary phosphorus in MCRF subjects, plasma calcitriol levels increased compared with baseline values. This study shows that these MCRF subjects were unable to respond with an increase in calcitriol to a PTH stimulus that produced a similar urine cAMP response in normal subjects. However, they were capable of responding to a reduction in phosphorus absorption with an increase in calcitriol.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
214.
The discriminability of crossed-disparity (near) and uncrossed-disparity as a function of their location in the upper-left, upper-right, lower-left, and lower-right quadrants of the visual field. Discriminability was assessed using choice reaction-time (RT) and accuracy measures. While near targets were recognized equally well in the upper and lower fields, far targets were perceived more easily in the upper visual field. The discriminability of far targets was particularly poor in the lower left quadrant. These results point to the existence of fundamental asymmetries in perceiving crossed and uncrossed disparities along the vertical and lateral axes. 相似文献
215.
The expressions of cysteine dioxygenase (CDO) gene in the liver, lung, skeletal muscle, and kidney were studied by in situ hybridization with a cDNA probe from rat liver CDO under normal conditions. Significant expression of the CDO gene was detected in the liver, lung, and kidney, but not skeletal muscle. In the liver, the signal was confined to the cytoplasm of the hepatocytes. Furthermore, the signal was stronger in the periportal than that in the perivenous areas. In the lung, an intensive signal was found in the bronchiolar epithelium. As to the kidney, an intensive signal was observed in the distal convoluted tubules, while no signal was found in the proximal convultions. 相似文献
216.
Silicone-gel-filled breast implants have been widely used for breast augmentation and reconstruction after mastectomy. The rate of implant rupture and its sequelae are not known. We review the frequency, causes, sequelae, and detection of implant rupture. Materials testing of removed implants provides evidence that as implants age in vivo, they weaken and may rupture. Sequelae of rupture include migration of gel accompanied by inflammation and silicone granuloma formation. The role of free silicone gel in relation to idiopathic or atypical connective tissue disease is not clear. Magnetic resonance imaging is substantially more sensitive in the detection of rupture than is mammography or ultrasonography. 相似文献
217.
BG Pollock 《Canadian Metallurgical Quarterly》1998,59(10):535-537
218.
Fiber-optic chemical sensor microarrays for the detection of pH and O2 have been developed with subsecond response times. Sensor microarrays are fabricated by the covalent immobilization (pH sensor arrays) or the physical entrapment (O2 sensor arrays) of fluorescent indicators in photodeposited polymer matrices on optical imaging fibers. Polymer microarrays are comprised of thousands of individual elements photodeposited as hemispheres such that each element of the sensor array is coupled directly to a discrete optical element of the imaging fiber and is not in contact with other neighboring elements. Because of the hemispherical shape and the individuality of the array elements, diffusion of analyte to the sensor elements is dominated by radial diffusion, resulting in a rapid response time. pH-sensitive arrays based on fluorescein respond to a 1.5-unit pH change within 300 ms, while the O2-sensitive arrays respond to O2 changes within 200 ms (90% of steady state response). 相似文献
219.
It has been known since the 1940s that nail polishes contain allergenic ingredients. The aim of this study was to clarify whether the nail polishes on the market today contain significant amounts of allergens, and what the solvents are. The following ingredients were determined: toluene, toluene sulfonamide formaldehyde resins, free formaldehyde, acrylates, methacrylates and certain organic solvents. The study comprised 20 brands and 42 samples. All the nail polishes analysed contained allergenic toluene sulfonamide formaldehyde resins (TSFR), in concentrations from 0.08 to 11.0%. The concentration of total formaldehyde varied from 0.02% to 0.5%. The more TSFR a nail polish contained, the higher was its formaldehyde content. Probably not only TSFR-allergic but also formaldehyde-allergic persons may get dermatitis from many of the nail polishes studied. The concentrations of acrylates and methacrylates were so small that they are of practical significance only to those previously sensitized to acrylates. Of the organic solvents, toluene was still widely used, whereas xylene was found in only 1 product. The nail polishes on the market today are not safe for all consumers. However, according to the regulations of the European Union, the packaging labeling of all cosmetic products must be supplied with a list of ingredients from the beginning of 1998. This will help the consumer to avoid allergenic products. A better alternative could, however, be to substitute the most allergenic ingredients with substances possessing minor allergy potency. 相似文献
220.
Fifteen patients underwent computed tomography (CT)-guided contrast material localization of pulmonary nodules, with barium and indigo carmine stain used in five patients, iodized oil and indigo carmine stain in five, and water-soluble contrast material and indigo carmine stain in five before fluoroscopy-assisted thoracoscopic resection. Contrast material localization was successful in all cases, and the surgeon confirmed accurate localization, CT-guided contrast material localization is simple and useful for thoracoscopic resection. 相似文献