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991.
The incidence of neural tube defects in a rural area of the west of Ireland from 1974 to 1985 was 2.96 per 1000. The prevalence was unchanged during the 11 years. When compared with a control group there was no increased incidence of anaemia in mothers of affected infants. 相似文献
992.
Stefano Sdringola Catalin Loghin Fernando Boccalandro K Lance Gould 《Journal of nuclear medicine》2006,47(1):59-67
Changes in regional myocardial perfusion throughout the entire coronary vascular tree, as opposed to changes in the worst regional perfusion defect, have not been described during long-term regression or progression of coronary artery disease (CAD) or related to clinical outcomes. METHODS: Four-hundred nine patients with CAD undergoing dipyridamole PET at baseline and after 2.6 +/- 1.4 y were followed over 5 more years for coronary events. PET images were objectively quantified by automated software for changes in severity of the (i) baseline worst quadrant, indicating the worst flow-limiting stenosis at baseline PET; (ii) follow-up worst quadrant, indicating the worst stenosis on follow-up PET; and (iii) maximal change quadrant, indicating the largest change of any same quadrant pair from baseline-to-follow-up images. RESULTS: At follow-up PET, new regional perfusion defects were seen in 40% of patients. In 77% of patients, the greatest change was in a quadrant different from the worst baseline defect. The maximal change quadrant improved in 70% of patients on intense lifestyle and pharmacologic lipid treatment, in 48% on moderate treatment, and in 39% on poor treatment (P < 0.0001). Combined quadrant changes integrated throughout the heart independently predicted cardiovascular events at long-term follow-up. In contrast, changes of any single baseline-to-follow-up quadrant pair did not. CONCLUSION: By PET, 77% of patients with CAD had the greatest perfusion changes in areas different from the baseline worst perfusion defect and 40% had new perfusion defects. Changes in perfusion defects throughout the entire coronary vascular tree predicted coronary events, whereas changes in the worst flow-limiting stenosis at baseline or in any one segment of myocardium did not. To our knowledge, these data provide the first direct evidence on mechanisms for disproportionately greater reduction in cardiac events than changes in single stenosis severity with lipid treatment. 相似文献
993.
Comparative assesment of gingival thickness using transgingival probing and ultrasonographic method.
A decided attitude of expectation among many patients has given a new perspective to regenerative and plastic periodonta surgery. With authors emphasizing on the importance of gingival thickness, attempts are being made to obtain necessary information atraumatically and rapidly. Hence in the present study an attempt has been made to compare the two methods of assessing gingival thickness i.e transgingival probing and ultrasonographic method and also assess the gingival thickness in relation to central incisor lateral incisor and canine in Indian population. The gingival thickness was assessed in patients with healthy gingiva by both the methods. It was observed that transgingival probing method significantly over estimated the thickness of gingiva than the ultrasonographic method and the thickness of gingiva varies with morphology of the crown. It was concluded that compared to transgingival probing ultrasonographic method assesses gingiva thickness more accurately, rapidly and atraumatically. 相似文献
994.
G. S. Bhumbra A. N. Inyushkin K. Saeb-Parsy A. Hon R. E. J. Dyball 《The Journal of physiology》2005,563(1):291-307
995.
The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion. 相似文献
996.
997.
K M Lux 《Journal of pediatric nursing》1991,6(3):159-165
Kawasaki disease is now the most common cause of acquired heart disease in America's children. It is an acute febrile illness that may cause coronary artery aneurysm formation in infected children. The results of a multicenter, randomized trial on the effect of intravenous administration of gamma globulin (IVGG) plus aspirin versus aspirin alone upon coronary aneurysm formation show a decrease in coronary aneurysm formation from the usual 20%-30% to 3%. Administration of IVGG presents some unique challenges for nurses. Also, the pediatric nurse must educate parents and children about this disease to prepare them for discharge and long-term follow-up care. 相似文献
998.
999.
Five treatment procedures evaluated for the elimination of ascorbate interference in the enzymatic determination of urinary oxalate 总被引:1,自引:0,他引:1
We evaluated the efficacies of five treatment procedures for eliminating ascorbate interference in the enzymatic determination of urinary oxalate. Aliquots of urine samples, containing different amounts of added ascorbate and oxalate, were individually subjected to ferric chloride, sodium nitrite, sodium periodate, charcoal, or ascorbate oxidase treatment to eliminate ascorbate interference. Oxalate contents of the urine samples were then determined by a banana oxalate oxidase-horseradish peroxidase-linked assay with 3-methyl-2-benzothiazolinone hydrazone and 3-(dimethylamino)benzoic acid as chromogens. Only those urine samples treated with ascorbate oxidase or charcoal consistently gave recovery of oxalate close to 100%. Treatment with other reagents, though improving the recovery of oxalate, gave inconsistent results. On the basis of these data, we describe procedures for simply and reliably assaying oxalate by using banana oxalate oxidase. 相似文献
1000.
K H Caron 《Seminars in Ultrasound, CT and MRI》1991,12(5):448-474
In many ways, MRI of the pediatric abdomen is in its infancy. Motion will be a problem with most of the current pulse sequences, but the problem appears manageable given many of the newer software options for motion suppression. Faster pulse sequences (approaching CT scan times) will serve to improve image quality and reduce the need for sedation. Identification of a reliable enteric contrast agent probably will expand the current utility of MRI beyond evaluation of solid abdominal viscera. Although preliminary results appear promising, controlled comparative studies are necessary to determine the exact role of MRI in diagnosis and staging of common pediatric abdominal malignancies. The addition of MRI intravenous contrast agents and MR spectroscopy are anticipated to add depth and specificity to the diagnostic potential of this exciting modality. 相似文献