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排序方式: 共有134条查询结果,搜索用时 15 毫秒
21.
Medicinal plants based traditional systems of medicines are playing important role in providing health care to large section of population, especially in developing countries. Interest in them and utilization of herbal products produced based on them is increasing in developed countries also. To obtain optimum benefit and to understand the way these systems function, it is necessary to have minimum basic level information on their different aspects. Indian Systems of Medicine are among the well known global traditional systems of medicine. In this review, an attempt has been made to provide general information pertaining to different aspects of these systems. This is being done to enable the readers to appreciate the importance of the conceptual basis of these system in evolving the material medica. The aspects covered include information about historical background, conceptual basis, different disciplines studied in the systems, Research and Development aspects, Drug manufacturing aspects and impact of globalization on Ayurveda. In addition, basic information on Siddha and Unani systems has also been provided.  相似文献   
22.
Thoracic spiral CT: influence of subsecond gantry rotation on image quality   总被引:3,自引:0,他引:3  
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Facial bone infarcts in sickle cell syndromes   总被引:2,自引:0,他引:2  
Royal  JE; Harris  VJ; Sansi  PK 《Radiology》1988,169(2):529
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25.
A retrospective review was done of 34 extremities studied between 1981 and 1985 with technetium-99m pyrophosphate scanning; 22 were subsequently amputated. Results of detailed pathologic examination or immediate postoperative examination of the resected extremity were available in 16 cases. In these cases, scanning had allowed correct prediction of the level of amputation and of the specific areas of muscle infarction in 13 cases. In the one case in which amputation was performed for infection rather than muscle necrosis, the lack of necrosis was correctly predicted with the scan. The limited results of this study indicate that the Tc-99m pyrophosphate scan allows the location of necrotic muscle to be predicted accurately and may therefore be a useful adjunct in determining the best level for ultimate amputation. Special caution is required in those cases in which muscle necrosis is due to acute causes (e.g., traumatic thrombosis) rather than chronic vascular disease.  相似文献   
26.
PURPOSE: To report the histological findings of four eyes of three patients who underwent epi-LASIK treatment for the correction of low myopia. METHODS: The epithelial sheets were harvested either immediately after separation (one eye) or were accidentally dislocated and harvested from the operative eyes 24 hours after treatment (three eyes). All sheets underwent optical and transmission electron microscopy. RESULTS: Histological evaluation showed that the majority of the epithelial cells were morphologically normal in all examined specimens. CONCLUSIONS: Histological examination of specimens in four eyes showed that 24 hours after mechanical separation the epithelial cells' morphology was close to normal.  相似文献   
27.
Paramagnetic agents enhance contrast between tissues in magnetic resonance (MR) imaging by altering tissue relaxation times. The effect of these changes on MR image intensity depends in part on the choice of operator-controlled pulse sequence parameters. With the newly described paramagnetic hepatobiliary contrast agent, iron(III) ethylenebis-(2-hydroxyphenylglycine), Fe(EHPG)-, an in vivo experimental analysis of pulse sequence optimization was performed on the rat. We compared the enhancement of the liver divided by background noise, EL/N, of standard inversion-recovery (IR) and spin-echo (SE) T1-weighted pulse sequences and several pulse sequences theoretically predicted to have improved EL/N. Optimization of the echo time (TE = TEmin) gave a substantial (greater than 60%) increase in EL/N over the standard IR and SE pulse sequences. Images obtained with optimized repetition rate and inversion time gave only a slight additional improvement. Within the uncertainties of our relaxation measurements, the measured changes in EL/N with pulse sequence optimization corresponded well with theoretical predictions. With the experimental and theoretical data, the importance of using a short echo time to obtain maximal T1 contrast in contrast-enhanced MR imaging and the relative merits of optimized SE versus IR pulse sequences for contrast-enhanced MR imaging are discussed.  相似文献   
28.
PURPOSE: To evaluate the clinical results of epi-LASIK, a new surface ablation surgical technique for the treatment of low myopia. SETTING: Vardinoyannion Eye Institute of Crete, University of Crete, Greece. METHODS: Forty-four eyes of 31 patients had epi-LASIK for the correction of low myopia. Mean preoperative spherical equivalent was 3.71 diopters (D) +/- 1.2 (SD) (range -1.75 to -7.00 D) and the mean baseline logMAR best spectacle-corrected visual acuity was -0.01 +/- 0.06 (range 0.10 to -0.10). All the epithelial separations were performed with the Centurion epikeratome (CIBA Surgical). The enrolled patients were followed daily until the epithelial healing was complete as well as at 1- and 3-month intervals. On the operative day, patients filled out a questionnaire grading visual performance and pain score of treated eyes every 2 hours for a total of 5 records. RESULTS: The mean epithelial healing time was 4.86 +/- 0.56 days (range 3 to 5 days). The mean logMAR uncorrected visual acuity on the day of reepithelization was 0.19 +/- 0.09 (range 0.40 to 0.10). At 1 month, the mean was spherical equivalent of the treated eyes (N=44), -0.3 +/- 0.6 D (range -1.0 to 0.87 D), and at 3 months it was (N=37), -0.10 +/- 0.4 D (range -0.75 to 0.75 D); 97% of eyes had clear corneas or trace haze 3 months after treatment. CONCLUSIONS: Preliminary clinical results suggest that epi-LASIK is a safe and efficient method for the correction of low myopia. Further studies will establish this method as an alternative surface ablation procedure.  相似文献   
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A new technique is described that allows for the creation of pure pulsatile flow magnetic resonance (MR) images in a single acquisition. Five to 16 electrocardiographically gated images spanning the entire cardiac cycle are obtained with use of a gradient-echo pulse sequence. The section can be varied from 4 mm thick to full thickness projection. Taken singly, each image provides direct assessment of flow direction and velocity. Subtraction of image pairs eliminates signal detected from stationary protons, producing images of pulsatile flow. In this study the technique was used to image the flow of cerebrospinal fluid (CSF) in healthy subjects and in one patient with syringohydromyelia. The data suggest that multiphasic MR imaging provides a powerful means for the noninvasive assessment of CSF pulsatile flow dynamics and may have potential clinical application for the investigation of a variety of abnormalities such as normal pressure hydrocephalus, syrinx, and spinal block.  相似文献   
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