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排序方式: 共有522条查询结果,搜索用时 15 毫秒
71.
Renal localization of gallium-67 citrate 总被引:1,自引:0,他引:1
72.
The authors describe the use of a desk-top computer to analyze processor status. Quality control data (sensitometry, densitometry, thermometry, etc.) are collected conventionally. Analysis of the data is subsequently performed using specially designed software. This computer analysis results in a small savings in time and in greatly improved management and presentation of quality control data. 相似文献
73.
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75.
甘草类黄酮对四氯化碳致小鼠急性肝损伤的影响 总被引:48,自引:0,他引:48
甘草类黄酮(GF)是从甘草根中提得。本文结果表明,预先ig GF 200,400,600mg·kg-1·d-1×2d能显著降低CCl4所致血清谷丙转氨酶,乳酸脱氢酶活性的升高以及肝内丙二醛含量的增加,其作用呈剂量依赖性。GF可减轻CCl4所致的肝脏坏死,但对血清内酶的活性没有抑制作用,也不减少正常小鼠血清中酶的活性。GF的肝保护作用可能与其抗脂质过氧化作用有关。 相似文献
76.
Matson GB; Twieg DB; Karczmar GS; Lawry TJ; Gober JR; Valenza M; Boska MD; Weiner MW 《Radiology》1988,169(2):541-547
Localized phosphorus-31 magnetic resonance (MR) spectroscopy in humans has previously been accomplished with surface coils by means of depth-resolved surface coil spectroscopy or rotating frame experiments, in which the extent of tissue sampled critically depends on surface coil placement. The authors' goal was to modify the surface coil image-selected in vivo spectroscopy (ISIS) experiment to accomplish three-dimensional volume selection through application of selective pulses in the presence of B0 gradients. Advantages of ISIS include the ability to use proton images to define the volume of interest (VOI) and reduced dependence on exact positioning of the surface coil. However, rapid replication of the surface coil ISIS experiment can cause spectral contamination from signals originating outside the VOI. A modified version of the ISIS experiment was developed to alleviate contamination under conditions of rapid replication. Applications of localized P-31 MR spectroscopy for observation of high-energy phosphorus metabolites are presented in human liver, heart, and transplanted and normal kidney. 相似文献
77.
Dendrimers have generated tremendous interest in the field of drug delivery. Despite indications of their utility as drug carriers, the inherent cytotoxicity associated with polycationic dendrimers acts as a limiting factor to their clinical applications. Many functionalization strategies have been adopted to mask peripheral amines in order to overcome this limitation. The object of the present investigation was to evaluate the effect of functionalization on the toxicological profile of fifth-generation poly(propylene imine) dendrimer (PPI-5.0G). Four forms of functionalized dendrimers, including protected glycine and phenylalanine, and mannose and lactose functionalized poly(propylene imine) (PPI) dendrimer, were synthesized as prospective drug carriers. These dendrimeric systems were evaluated for haemolytic toxicity, cytotoxicity, immunogenicity and haematological parameters. PPI-5.0G demonstrated a positive charge-based time- and concentration-dependent toxicity profile. Functionalization greatly improved the toxicity profile of the parent dendrimer. Hence it is proposed that these functionalized forms of PPI dendrimer have great potential as bio-compatible drug vehicles. 相似文献
78.
Gupta U Agashe HB Asthana A Jain NK 《Nanomedicine : nanotechnology, biology, and medicine》2006,2(2):66-73
Dendrimers have emerged as one of the most interesting themes for researchers as a result of their unique architecture and macromolecular characteristics. Several groups are involved in exploring their potential as versatile carriers in drug delivery. The use of dendrimers in drug delivery has been reviewed extensively. The increasing relevance of the potential of dendrimers in drug delivery emphasizes the need to explore the routes by which they can be administered. The present review focuses on dendrimer-mediated drug delivery based on various routes of administration, a topic that has received little attention in the available literature. With this focus in mind, we present a comprehensive exploration of the recent advances in the investigational aspects of these nanoscopic polymeric devices. Also included are some in vitro studies that present data suggestive of their possible application in different routes of administration. 相似文献
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80.
BACKGROUND: This study investigated whether a tensioning headband that applies up to 20 mmHg pressure over a forehead pulse oximetry sensor could improve arterial hemoglobin oxygen saturation reading accuracy in presence of venous pooling and pulsations at the forehead site. METHODS: Healthy volunteers were studied breathing room air in supine and various levels of negative incline (Trendelenburg position) using the forehead sensor with the headband adjusted to its maximum and minimum recommended pressure limits. Saturation readings obtained from the forehead sensor with the subjects supine and the headband in place were used as a baseline to compare the effects of negative incline on reading accuracy when using and not using the headband. Occurrences of false low-saturation readings detected by forehead sensors were compared with those from digit sensors. RESULTS: No difference was observed between saturation readings obtained from the forehead sensor in supine and negative incline positions when the headband was applied. Forehead sensor readings obtained while subjects were inclined and the headband was not used were significantly lower (P < 0.05) than the supine readings. There was no statistically significant difference between the digit and forehead sensor in reporting false low-saturation readings when the headband was applied, regardless of body incline. CONCLUSIONS: Application of up to 20 mmHg pressure on the forehead pulse oximetry sensor using an elastic tensioning headband significantly reduced reading errors and provided consistent performance when subjects were placed between supine and up to 15 degrees head-down incline (Trendelenburg position). 相似文献