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排序方式: 共有449条查询结果,搜索用时 31 毫秒
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G W Blunn A B Joshi P A Lilley E Engelbrecht L Ryd L Lidgren K Hardinge E Nieder P S Walker 《Acta orthopaedica Scandinavica》1992,63(3):247-255
106 unicondylar knee replacement tibial components were retrieved and analyzed for the amount and type of polyethylene wear. Three different designs were retrieved which had essentially the same femorotibial conformity. Each design showed a characteristic failure pattern. The polyethylene of PCA tibial components showed serious delamination after only short durations, as a result of heat pressing. St Georg sledge prostheses showed some delamination after 4 years' duration due to sub-surface cracks which were initiated by fusion defects in the polyethylene; metal backing of the components did not affect delamination of this prosthesis. The Marmor designs showed the least wear, with shiny depressions and surface pitting; no delamination was observed in the Marmor prosthesis. Molecular weight determination by gel permeation chromatography and analysis of crystallinity using Fourier transformation infra-red spectroscopy demonstrated that St George polyethylene had higher molecular weight and crystallinity than Marmor polyethylene. In some of the components investigated, crystallinity and molecular weight of the polyethylene were reduced under the wear track when compared with the unworn polyethylene. Since fusion defects may cause delamination of polyethylene we urge manufacturers to reduce the number of such defects. 相似文献
4.
D. Dickerson B. Adams G. Engelbrecht G. Boltman R. Hickman D. Kahn 《Transplant international》1992,5(Z1):S63-S64
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period. 相似文献
5.
H Engelbrecht 《Angewandte Parasitologie》1984,25(1):3-11
The ultrastructure of the bladder tegument of the metacestode of Taenia saginata, with considerations on the establishment in the definitive host. The tegument surface of invaginated Taenia saginata metacestodes was demonstrated by scanning electron micrograph. The tegument is folded irregularly and its surface is amplified by the presence of microtriches, 44-45 microtriches/micron 2. The microtriches are about 500 nm long and have an absorptive function. Likely, form and sensity of microtriches turn out a capillary attraction that plays an important role in contact with surface (finger, tongue and duodenum of man, instrumentarium , glass, plastics). This opinion is supported by scanning electron micrograph of the surface of finger-tips, of the tongue and the duodenum of man. 相似文献
6.
G F Rowland D J Engelbrecht E J Pool E C Schmollgruber G J Thompson K J van der Merwe 《Journal of virological methods》1989,25(3):259-269
An ELISA test system for detection of plant viruses in field samples is described, based on the unlabelled antibody method using a peroxidase-antiperoxidase (PAP) complex. Novel features of the system include the use of acid-treated naked bacteria as combined carrier-adjuvants for the production of rabbit antiviral antibodies, and the use of acid-treated chicken antibodies (IgY) for antigen trapping in the ELISA. Systems for detection of potato virus Y (PVY), potato leafroll virus (PLRV), grapevine fanleaf virus (GFV) and grapevine virus A (GVA) were developed and compared with conventional direct double antibody sandwich (DAS) systems in tests with both purified virus and field samples. The PAP systems offer improved sensitivity, no background problems in the outer rows of the microtitre plates and are much easier to visualize with the naked eye if no plate reader is available. 相似文献
7.
MR imaging of the male pelvis 总被引:2,自引:0,他引:2
Barentsz JO Engelbrecht MR Witjes JA de la Rosette JJ van der Graaf M 《European radiology》1999,9(9):1722-1736
Prostate and urinary bladder cancer are the most frequently encountered malignancies of the urinary tract. Appropriate use
of the different imaging techniques is crucial for accurate assessment of prognosis and for the development of appropriate
treatment planning. Especially determination of local tumor extension and detection of nodal or bone metastases is extremely
important. In this regard MR imaging is the most promising imaging technique. Therefore, in this review its role in staging
these malignancies is evaluated and compared with clinical staging, and other imaging techniques. Finally, future developments,
such as new sequences, new contrast agents, the role of surface coils and MR-guided biopsy, are considered. Also, the preferred
radiological approach is discussed. 相似文献
8.
We report two cases of idiopathic intracranial hypertension in patients with Graves' ophthalmopathy. These patients, with known Graves' ophthalmopathy, presented with new onset optic disc edema and preserved visual function. Moderate enlargement of the extraocular muscles was observed in one case and moderate expansion of the orbital fat volume was observed in the second case. Lumbar puncture revealed an elevated opening pressure and normal cerebrospinal fluid composition in both patients. Also, no intracranial abnormalities were seen with neuroimaging studies. The findings in these patients suggest idiopathic intracranial hypertension as a second concurrent diagnosis, and should be considered as a possible etiology of optic disc edema in patients with Gravest ophthalmopathy and preserved visual function. 相似文献
9.
Boström J Janssen G Messing-Jünger M Felsberg JU Neuen-Jacob E Engelbrecht V Lenard HG Bock WJ Reifenberger G 《Journal of neurosurgery》2000,93(2):335-341
The authors report on an 11-year-old boy in whom proptosis of the eye caused by a benign intraosseous xanthofibroma of the left orbital wall became clinically apparent at the age of 4 years. Two years later he developed bilateral papilledema, at which time computerized tomography and magnetic resonance studies revealed multiple enhancing intracranial lesions. The largest mass was located in the left middle fossa; other lesions were located at the tentorium cerebelli, in both lateral ventricles, near the superior sagittal sinus, and extracranially near the left jugular vein. The mass in the left middle fossa was resected and diagnosed as juvenile xanthogranuloma (JXG). Thirty months later, the patient again became symptomatic, exhibiting behavioral abnormalities and a decrease in mental powers. At that time, the two remaining lesions in both lateral ventricles had grown enough to cause trapping of the temporal horns and raised intracranial pressure. These lesions were successively resected and histopathologically confirmed to be JXGs. However, resection of the second intraventricular lesion was complicated by postoperative bilateral amaurosis, presumably caused by postdecompression optic neuropathy. According to a review of the literature, fewer than 20 patients with JXG involving the central nervous system have been reported. The patient described in this report is the first in whom multiple intracranial JXGs developed in the absence of cutaneous manifestations. Although JXGs are biologically benign lesions, the treatment of patients with multifocal and/or progressive intracranial manifestations is problematic. 相似文献
10.
Denny C Zacharias ME Ruiz AL do Carmo E do Amaral M Bittrich V Kohn LK de Oliveira Sousa IM Rodrigues RA de Carvalho JE Foglio MA 《Phytotherapy research : PTR》2008,22(1):127-130
An activity-guided fractionation of Virola sebifera Aubl. methylene chloride-soluble fraction provided novel 3,5-dihydro-2-(1'-oxo-3'-hexadecenyl)-2-cyclohexen-1-one (3), two known lignans (1, 2) and dehydro hexadecanoyl resorcinol (4). Isolation and purification were conducted with the application of column chromatography and structures were assigned by spetral analysis (1D and 2D NMR, HREIMS). Compounds 1-4 were evaluated for cytotoxic activities against human tumour cell lines UACC62 (melanoma), MCF-7 (breast), NCI 460 (lung, non-small cells), OVCAR03 (ovarian), PC-03 (prostate), HT-29 (colon), 786-0 (renal) and NCI-ADR (breast expressing phenotype multiple drugs resistance) in vitro. The new polyketide (3) showed selectivity against human OVCAR03 and NCI-ADR cell lines, ranging from 2 to 4 microg/mL. 相似文献