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以正交设计筛选处方,研制了安心酮注射剂,考察了制剂的稳定性,有效期为2.85年。采用酸性染料比色法测定注射剂中安心酮的含量,平均回收率为98.7%(RSD=0.44%)。本品对离体灌流豚鼠心脏的作用与原药相似。 相似文献
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A 1-mm-thick, stationary, ultrahigh-strip-density, focused grid was evaluated with respect to patient radiation dose and mammographic image quality as it affected the resolution of microcalcifications and masses. Radiographic technique was varied to determine the most useful alteration to improve image quality with the grid. Results from 89 patients demonstrated that no improvement in diagnostic ability was found in women with fatty breasts. As breast density increased, the advantage of the grid technique became more apparent. Grid mammography also often solved the problem of questionable microcalcifications with improved visualization of their number and geometry. 相似文献
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Feinberg DA; Mills CM; Posin JP; Ortendahl DA; Hylton NM; Crooks LE; Watts JC; Kaufman L; Arakawa M; Hoenninger JC 《Radiology》1985,155(2):437-442
Spin-echo magnetic resonance (MR) imaging detects a variety of pathologic states with great sensitivity. A technique for producing multiple spin-echo images in multisection operation is presented. This method of intensity-image acquisition is compared with retrospective intensity-image synthesis from routine data sets. Both yield long echo time (TE) images with similar image contrast and comparable and often increased diagnostic utility. Technical and clinical considerations are addressed, including signal-to-noise levels, flow effects, and patient throughput. 相似文献
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Asphyxiating thoracic dysplasia or Jeune's disease is a hereditary condition characterized by typical roentgenologic changes of the ribs, pelvis and extremities. Affected infants have very narrow chests and suffer from respiratory insufficiency which often leads to early death.
A large family of Arabic and Greek origin is described. Two siblings were dwarfed, had narrow chests and skeletal changes similar to those seen in Jeune's disease. In both infants widening and shortening of the left lower ribs and a trident appearance of the pelvis was demonstrated. One child who was severely mentally retarded died in infancy from bronchopneumonia and the other suffers from respiratory difficulties. Other members of the family had roentgenologic changes of the pelvis, spine and skull and mental retardation, features which have not previously been described in this disease. 相似文献
A large family of Arabic and Greek origin is described. Two siblings were dwarfed, had narrow chests and skeletal changes similar to those seen in Jeune's disease. In both infants widening and shortening of the left lower ribs and a trident appearance of the pelvis was demonstrated. One child who was severely mentally retarded died in infancy from bronchopneumonia and the other suffers from respiratory difficulties. Other members of the family had roentgenologic changes of the pelvis, spine and skull and mental retardation, features which have not previously been described in this disease. 相似文献
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Exhaled-breath condensate pH can be safely and continuously monitored in mechanically ventilated patients 总被引:2,自引:0,他引:2
BACKGROUND: Airway inflammation in acute and chronic respiratory diseases is characterized in part by abnormal pH in airway-lining fluid. The pH of exhaled-breath condensate (EBC) is low (acidic) in various pulmonary inflammatory diseases, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, pneumonia, and acute respiratory distress syndrome. Because the time course of pH changes in the airway is not yet clear, we aimed to develop a method for frequent and intensive EBC pH data collection in mechanically ventilated patients. METHODS: We examined the collection, gas-standardizing (CO2 removal), and continuous monitoring of pH of EBC from the expiratory port of a Servo-i ventilator with mechanically ventilated patients. We developed a condensing device that attaches to the exhaust port and is chilled by an electric cooling system. We built a 2-chamber gas-standardization and pH-measuring device that attaches to the condensing system and records pH every 6 s. After safety testing, we enrolled mechanically ventilated patients (with diverse reasons for requiring ventilatory support) for up to 96 h of continuous EBC pH condensimetry. RESULTS: The pressure, volume, and flow of the ventilator attached to a test lung were unchanged by application of the condensimeter, at various flows (2-120 L/min) and ventilator settings. We monitored 19 pediatric patients for 6-96 h. The pH of the accumulated EBC in the storage container correlated with the geometric mean of all the pH data points from the condensimeter during the recording period (r2 = -0.95, p < 0.001), which internally validated that the condensimetry system provides accurate, well gas-standardized readings for up to 96 h. The EBC pH values were similar to published reports of single samples. The EBC pH became more acidic during clinical deterioration and normalized with recovery. CONCLUSION: Continuous monitoring of EBC pH from the ventilator exhaust port is safely achievable and reliably provides data that may become useful in monitoring critically ill patients. 相似文献
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Robertson HT Smith DL Pajewski NM Weindruch RH Garland T Argyropoulos G Bokov A Allison DB 《The journals of gerontology. Series A, Biological sciences and medical sciences》2011,66(3):279-286
Many rodent experiments have assessed effects of diets, drugs, genes, and other factors on life span. A challenge with such experiments is their long duration, typically over 3.5 years given rodent life spans, thus requiring significant time costs until answers are obtained. We collected longevity data from 15 rodent studies and artificially truncated them at 2 years to assess the extent to which one will obtain the same answer regarding mortality effects. When truncated, the point estimates were not significantly different in any study, implying that in most cases, truncated studies yield similar estimates. The median ratio of variances of coefficients for truncated to full-length studies was 3.4, implying that truncated studies with roughly 3.4 times as many rodents will often have equivalent or greater power. Cost calculations suggest that shorter studies will be more expensive but perhaps not so much to not be worth the reduced time. 相似文献