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51.
Bone scintigraphy is the primary method for the diagnosis of skeletal métastases. This investigation is sensitive, but the interpretation must be performed in the knowledge that it is also nonspecific. Despite this, a correct diagnosis can usually be achieved. The first-hand supplementary investigation, after a doubtful scintigraphic finding, is radiography. In most cases this is sufficient for a diagnosis. When a scintigraphic abnormality cannot be adequately explained, usually because of a negative radiographic examination, a more sensitive modality must be used. Computerized tomography offers increased sensitivity and specificity, and is primarily used for this purpose. In this way contrast resolution is increased and problems caused by obscuring tissue and complicated anatomy are reduced. Since bone metastases migrate via the active bone marrow an alternative supplementary investigation is bone marrow scintigraphy. Its usefulness is restricted by disturbing activity, from the liver and the spleen, which obscures a significant part of the active marrow, and by the fact that a lesion must be of a certain size to become apparent. Magnetic resonance imaging yields excellent images of the extension of a tumor in soft tissue. Owing to high costs and restricted availability it is still mainly used for preoperative location of metastases. 相似文献
52.
Johannes Irsch Rudolf Hendriks Hans Tesch Ruud Schuurman Andreas Radbruch 《European journal of immunology》1993,23(2):481-486
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes. 相似文献
53.
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55.
Ingemar Sernbo Hans Holmquist Inga Redlund-johnell Olof Johnell 《Acta orthopaedica》1994,65(3):295-298
During 1984-1985, 410 patients with cervical hip fracture were randomized between 2 methods of internal fixation-a single nail (Rydell) or 2 LIH hook pins (LIH). The patients were followed-up prospectively for at least 2 years. Radiographs were taken after 1 week, 1, 3, 6, 12, and 24 months. The radiographs of the 295 paients alive 2 years postoperatively were examined by one of the authors. The sliding and the diversion of the pins and the nail in the anteroposterior projection and the diversion in the lateral projection were measured. In the failure group (non-union, late segmental collapse), the greatest sliding was noted within 1 month postoperatively and the diversion increased up to 3 months. Significant differences between the failure and the non-failure groups could be seen even after 1 week. We also found that the degree of sliding of the LIH pins and the Rydell nail 1 month postoperatively is comparable to the scintigraphic pattern 2 weeks postoperatively in predicting failure after nternal fixation of cervical hip fractures. 相似文献
56.
Richard Kitz Markus A. Rose Heidrun Schönborn Stefan Zielen Hans J. Böhles 《Pediatric allergy and immunology》2006,17(2):112-117
Polyunsaturated fatty acids (PUFAs) are components of cell membranes and may play an immunomodulating role in the pathogenesis of atopic dermatitis (AD). The goal was to determine the impact of PUFAs on AD by dietary supplementation of infants. Based on the parents' decision on their babies' primary feeding, mothers and newborns were randomized to the supplementation with gamma-linolenic acid (GLA) or placebo for up to 6 months. Breastfed infants received GLA by supplementing their mothers. Formula diet was commercial whey hydrolysate unsupplemented with PUFAs. Of 131 eligible infants, 24 developed AD within the first year of life. Of these, nine belonged to the exclusively breastfed group (n = 58), 14 to the combined-fed group (n = 53), and one to the never breastfed group (n = 20). We could not find an influence of GLA on the development of AD. In subjects with AD, at 1 yr of age the serum-immunoglobulin E (IgE) was the lowest in the GLA-supplemented group A-subjects. In the GLA-supplemented group, GLA-levels in breast milk were similar in atopic and non-atopic infants. In the non-supplemented group the GLA-content of breast milk was 0.07% of total fatty acids in atopic infants vs. 0.17% in non-atopic infants (p < 0.01). Dietary GLA-supplementation could not prevent AD. Interestingly, the number of infants developing AD was the lowest in never breastfed children. In infants suffering from AD, GLA-supplementation seemed to reduce total IgE in the first year of life. 相似文献
57.
Philip F. J. Hoyng Nynke de Jong Hans Oosting Jan Stilma 《International ophthalmology》1992,16(2):65-73
Platelet aggregationin vitro, deterioration of visual field defects (VFD) and the prevalence of disc haemorrhages (DH) were assessed in 49 patients with primary open angle glaucoma (POAG) and compared with the findings for 67 individuals with suspected glaucoma (GS) in a seven-year follow-up study (range 5.8 to 8.2 years). The percentage patients with spontaneous platelet aggregation (SPA) was higher for POAG patients with visual field deterioration (60%) than both POAG patients without progressive loss of visual fields (12.5%; P<0.005) and those with suspected glaucoma (22.4%; P<0.005). The occurrence of DH was higher among POAG patients with progressive loss of visual field (28%) compared to the GS group (8.4%; P<0.025) and the group of patients consisting of POAG patients without deterioration of VFD and GS (9.9%; P<0.05). DH also occurred more often in patients with low tension glaucoma (41.6%) than in the remaining POAG patients (13.5%; P<0.05). No relation between the patients with SPA and the patients with DH was observed.Abbreviations NPB
normal platelet behavior
- SPA
spontaneous platelet aggregation
- DH
disc haemorrhage 相似文献
58.
Diagnosis of scaphoid fractures:A prospective multicenter study of 1,052 patients with 160 fractures
Bo Munk Johnny Fr kj r Claus Falck Larsen Hans Gad Johannsen Lars Lundager Rasmussen Annette Edal Lilla Demeney Rasmussen 《Acta orthopaedica》1995,66(4):359-360
In a prospective multicenter study of 1,052 patients with clinical signs of a scaphoid fracture, mammo-graphic films and fine intensifying screens were used at the radiographic examination. 5 standardized projections including 3 special projections focused on the scaphoid were taken. 150 fractures were diagnosed at the first examination but in 10 cases the fracture was first diagnosed at a second radiographic examination after 10-14 days.
The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections. 相似文献
The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections. 相似文献
59.
The morphologic effects of androgen deprivation in the different lobes of the rat prostate were examined by light microscopic morphometry. The prostates of Wistar male rats (260-340 g) were fixed in situ by glutaraldehyde perfusion in castrated animals 1 week after gonadectomy and in intact animals. The ventral (VP), dorsal (DP), and lateral (LP) lobes as well as the coagulating gland (CG) were dissected out, weighed, and processed for light microscopy. Using stereologic methods the following parameters were estimated for each lobe: volume fraction of connective tissue, epithelium and glandular lumina, average epithelial height, average epithelial cell volume, and total number of epithelial cells. Castration leads to a 58-76% reduction of the wet weight of all prostatic lobes. The decrease of glandular tissue is greater in VP than in LP, DP, and CG. In VP and LP, there is a 39-45% reduction of the epithelial height, and this effect is less pronounced in DP and CG. For all lobes, the shrinkage of average epithelial cell volume is in the same range (25-30%). Moreover, in VP and LP, there is a 70% reduction of the total number of cells, whereas the reduction is less in DP and CG. It thus seems that the reduction of prostatic epithelial tissue mass upon castration is due to a reduction of the number of cells as well as a reduction of the volume of individual cells. VP and LP appear to be more androgen-dependent than DP and CG. 相似文献
60.
Prospective comparison of hip fracture treatment: 856 cases followed for 4 months in The Netherlands and Sweden 总被引:1,自引:0,他引:1
Margaretha Berglund-R d n Bart A. Swierstra Hans Wingstrand Karl-G ran Thorngren 《Acta orthopaedica》1994,65(3):287-294
In a prospective multicenter study 1115 hip fracture patients were registered in Rotterdam (The Netherlands), Sundsvall and Lund (Sweden). The patients had similar background parameters with a mean age of 78 years, about half of them living alone and just above 80 percent coming from independent living
For cervical fracture, hemiarthroplasty was the predominating treatment in Rotterdam (n 169), whereas osteosynthesis was used in Sundsvall (screws n 135) and Lund (hook-pins n 148). The mean (median) hospitalization time was 32 (20) days in Rotterdam, 16 (12) days in Sundsvall, and 17 (10) days in Lund. Discharge to independent living varied from 53 percent in Lund to 72 percent in Sundsvall. Functional outcome (walking ability and ADL capacity) was at 4 months similar in all groups, but at 2 weeks was lower in Rotterdam. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 4/9/20, in Sundsvall 2/4/13, and in Lund 01311 0 percent.
Trochanteric fractures were treated by screwplate in Rotterdam (n 146) and Lund (n 78), and by Ender nails in Sundsvall (n 11 7). The mean (median) hospitalization time was in Rotterdam 39 (29) days, in Sundsvall 24 (1 5) days and in Lund 19 (11) days. Discharge to independent living varied from 41 percent in Lund to 57 percent in Sundsvall. Functional outcome was similar between the groups. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 2/6/14, in Sundsvall 611 2/19 and in Lund 12/12/18 percent.
Thus, our study has shown that it is possible to perform a prospective multicenter study involving different European countries. The functional out- come after 4 months was very consistent between the centers studied, irrespective of choices made concerning operation method and rehabilitation routines. However, a difference in mortality within these first postoperative months was found, which seems attributable to the operation procedure. 相似文献
For cervical fracture, hemiarthroplasty was the predominating treatment in Rotterdam (n 169), whereas osteosynthesis was used in Sundsvall (screws n 135) and Lund (hook-pins n 148). The mean (median) hospitalization time was 32 (20) days in Rotterdam, 16 (12) days in Sundsvall, and 17 (10) days in Lund. Discharge to independent living varied from 53 percent in Lund to 72 percent in Sundsvall. Functional outcome (walking ability and ADL capacity) was at 4 months similar in all groups, but at 2 weeks was lower in Rotterdam. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 4/9/20, in Sundsvall 2/4/13, and in Lund 01311 0 percent.
Trochanteric fractures were treated by screwplate in Rotterdam (n 146) and Lund (n 78), and by Ender nails in Sundsvall (n 11 7). The mean (median) hospitalization time was in Rotterdam 39 (29) days, in Sundsvall 24 (1 5) days and in Lund 19 (11) days. Discharge to independent living varied from 41 percent in Lund to 57 percent in Sundsvall. Functional outcome was similar between the groups. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 2/6/14, in Sundsvall 611 2/19 and in Lund 12/12/18 percent.
Thus, our study has shown that it is possible to perform a prospective multicenter study involving different European countries. The functional out- come after 4 months was very consistent between the centers studied, irrespective of choices made concerning operation method and rehabilitation routines. However, a difference in mortality within these first postoperative months was found, which seems attributable to the operation procedure. 相似文献