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排序方式: 共有632条查询结果,搜索用时 687 毫秒
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Direct sagittal computed tomography (CT) was performed in 454 patients thought to have internal derangement of the temporomandibular joint (TMJ). Of 905 joints examined, 71 were subsequently studied using arthrography and/or surgery. Sensitivity was 91.8%, accuracy 87.3%, and the positive predictive value 93.3%. Degenerative joint disease was detected in 33.6% of joints with anterior meniscal displacement but no reduction, 15.3% of those with displacement and reduction, and 5.0% of those with no identifiable meniscal abnormality. It is concluded that direct sagittal CT is a sensitive and effective method of detecting and characterizing displacement of the TMJ meniscus as well as underlying degenerative joint disease. 相似文献
555.
Cryopreservation: the practicalities of evaluation 总被引:13,自引:8,他引:5
Jones HW Jr; Out HJ; Hoomans EH; Driessen SG; Coelingh Bennink HJ 《Human reproduction (Oxford, England)》1997,12(7):1522-1524
An attempt was made to integrate data from cryopreserved embryos with those
from fresh embryos to obtain a realistic assessment of the role of
cryopreservation in assisted reproductive treatment. Principles were
applied to previously published data from a large prospective randomized
multicentre study comprising recombinant and urinary follicle stimulating
hormone in in-vitro fertilization.
相似文献
556.
BM Junghans PhD SG Crewther PhD DP Crewther PhD B Pirie 《Clinical & experimental ophthalmology》1997,25(4):103-105
Purpose: Although it is generally thought that lymphatics do not exist in the choroid, there is mounting evidence that lymphatic-like structures do exist in primates and fowl. Methods/Results: Our comparison of the ultrastructure of chick and rabbit outer choroid indicates that major differences exist in the non-vascular areas of the choroid: notably, the chick has large lymphatic sinusoids, whereas the rabbit only has a system of large vacuoles contained within the processes of individual fibroblasts. Conclusions: These results raise questions regarding the similarities or otherwise between species of the management of retinal metabolites, excess tissue fluid and choroidal homeostasis, especially during conditions of overload. 相似文献
557.
Ramella-Virieux SG; Steghens JP; Barbieux A; Zech P; Pozet N; Hadj-Aissa A 《Nephrology, dialysis, transplantation》1997,12(3):449-455
BACKGROUND: Extracellular types (high-Na) of cold-storage solution (CSS)
have been shown to be more effective in preserving kidneys than
intracellular CSS (high-K). On the other hand, calcium entry blockers (CEB)
have been demonstrated to improve graft function when administered after
and/or prior to transplantation. The ischaemia reperfusion syndrome
involves, in part, an alteration in intracellular calcium metabolism that
induces an increase in renal vascular resistances (RVR) and other cellular
dysfunction, and high-K CSS per se are vasoconstrictive. Since CEB act via
a modification in intracellular calcium metabolism on vascular smooth
muscle, glomerular, and tubular cells, we evaluated the actual benefit on
CEB on kidneys preserved in Belzer's CSS (K-UW) and a high-Na version of
Belzer's CSS (Na-UW). METHOD: The isolated perfused rat kidney (IPK) was
used, first as a vascular bed to test the effects of CSS on RVR, and the
influence of nifedipine. Second, the recovery function of the IPK was
assessed by GFR and tubular Na reabsorption, after 24 h preservation in
K-UW and Na- UW, with or without nifedipine. Results were compared with a
control group in which renal function was measured without prior
cold-storage. RESULTS: K-UW but not Na-UW induced an increase in RVR when
flushed into the kidney. This vasoconstriction is prevented by nifedipine.
K-UW CSS was more deleterious to renal function than Na-UW. Addition of
nifedipine to the flush, the CSS for 24 h, and to the normothermic
reperfusate further improved recovery function of the IPK cold stored in
Na-UW but not in K-UW, without any modification of RVR. CONCLUSION:
Nifedipine may be of potential effect in attenuating ischaemic injury by a
mechanism which does not involve its vasodilatory properties.
相似文献
558.
Erik K. Insko Thomas J. Connick Mitchell D. Schnall Susan G. Orel 《Magnetic resonance in medicine》1997,37(5):778-784
An RF multicoil array for high resolution imaging of the breast is presented. The RF multicoil is incorporated into a dedicated breast imaging apparatus that holds either breast in gentle compression during imaging. Simulations and imaging experiments demonstrate the high sensitivity and RF homogeneity of the multicoil array. Direct comparisons are made between the multicoil and a surface coil. In vivo images are presented to demonstrate the homogeneity of the RF field of the multicoil over the entire breast. An in vivo image of both high temporal and spatial resolution is shown, which demonstrates the sensitivity of the RF multicoil array that may be achieved in a practical imaging experiment. 相似文献
559.
Mueller PR; Saini S; Simeone JF; Silverman SG; Morris E; Hahn PF; Forman BH; McLoud TC; Shepard JO; Ferrucci JT Jr 《Radiology》1988,169(1):1-4
Twenty-six pleural biopsies were performed on 23 patients over a 3-year period. Twenty-three biopsies were performed guided with ultrasound; one, with computed tomography; and two, with fluoroscopy. Indications for an image-guided pleural biopsy were (a) pleural masses or thickening that were either not seen on chest radiographs or seen only on one view and (b) small or loculated pleural effusions of unknown cause with no mass seen. If only pleural fluid was present, reverse bevel needles were used for biopsy (n = 15). If a discrete pleural mass or thickening was seen with cross-sectional imaging, standard (16-20 gauge) biopsy needles were used (n = 11). In the 23 patients, biopsy results were true positive in ten (nine with malignancy, one with tuberculous pleurisy), true negative in ten (confirmed either at subsequent thoracotomy or clinical follow-up), and false negative in three. Complications were few, with a significant pneumothorax occurring in two patients (8.7%). Image-guided biopsy of small pleural lesions and small pleural effusions can be performed by the radiologist who understands the special needles and techniques involved. 相似文献
560.