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Root-form implants may be indicated for the replacement of missing anterior teeth. Occasionally fixtures are placed in a position inconsistent with proper tooth alignment. The new PreAngled Abutment (Dentsply/Implant Division, Encino, CA) addresses this problem and was used to successfully restore missing tooth numbers 7 and 8 for a patient that had two malpositioned implants. 相似文献
283.
Inflammatory bowel disease, in addition to intestinal involvement, may be complicated also by other extra-intestinal manifestations. Moreover, drugs commonly employed in the treatment of ulcerative colitis and Crohn's disease may induce iatrogenic pancreatitis. Acute pancreatitis is described in two ulcerative colitis patients following azathioprine treatment. 相似文献
284.
Natural occurrence of Fusarium mycotoxins (trichothecenes and fumonisins) and aflatoxin B1 (AFB1) were surveyed in 32 corn samples, harvested in 1993 and randomly sampled in 1994 in several districts of Hanoi, Vietnam. Corn samples were first milled into fine powder, extracted with methanol-water (3:1) and the crude extracts obtained from the same samples were used for the simultaneous analysis of the trichothecenes such as nivalenol (NIV), deoxynivalenol (DON), and T-2 toxin (T-2) by gas chromatography/mass spectrometry (GC/NS); fumonisins B1 (FB1), B2 (FB2), and B3 (FB3) by high-performance liquid chromatography (HPLC) with a flourescence detector; and AFB1 by and ELISA kit based on a monoclonal antibody. The data revealed that 14, 8, 4, 3, and 2 out of 15 corn kernel samples were positive for AFB1, FB1, FB2, FB3, and NIV with the average levels being 28, 1, 101, 276, 232, and 858 ppb, respectively, and neither DON nor T-2 were detected. As for the other 17 samples of corn powder, 13, 15, 12, 10, 4 and 2 were positive for AFB1, FB1, FB2, FB3, DON, and NIV with the average being 30, 780, 289, 176, 3, 170, and 1,365 ppb, respectively, and T-2 was not detected. Although their positive rates and levels fell in the ranges reported elsewhere, it was found for the first time that the Fusarium toxins (NIV, DON, and fumonisins) and an Aspergillus toxin (AFB1) were naturally co-contaminated in selected samples of corn produced in north Vietnam. 相似文献
285.
For the diagnosis of lumbar P.I.D. discography is much superior to myelography. The risks of both techniques are the same, but the side-effects of discography are clearly less. Higher lesions remain a problem if they do not show up neurologically (s. the prolapsed disc at L 2/3). Here segmental blocking, posterior gaping of the intervertebral space and displacement of the dural sac show clearly the posterior prolapse. In the standard discogram of the lower 3 discs it would have been missed. In spite of this our present experience with lumbar discography is so positive, that we are about to test a long term series, whether and to which extend discography could replace myelography in cases where there is no hint at a space-occupying lesion, other than a disc or whether the order of these investigations should be reversed. 相似文献
286.
The late stage of serpiginous (geographic) choroiditis 总被引:2,自引:0,他引:2
Questionnaires rating twins' physical similarity and similarity of dress were obtained from the parents of 121 identical and 70 same-sex fraternal twin pairs. Within-pair difference scores on several behavioral measures (two intelligence tests, two perceptual tests, one reading test, one test of speech articulation, and one personality inventory) were correlated with the twins' scores for physical similarity and similarity of dress. The correlations revealed no systematic relation between the similarity of appearance and the similarity of behaviors for either the identical twin pairs or the same-sex fraternal twin pairs. The assumption that twins' behaviors are more alike because they are more similar in appearance does not seem warranted. 相似文献
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