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11.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia.  相似文献   
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The stability of implanted artificial joints is limited. One main factor for this is the change of the bone tissue near the implant. Therefore we studied femura with stem endoprostheses derived from autopsy. All specimens were cut in horizontal and longitudinal sections. X-rays were made of all sections. Then the specimens were embedded undecalcified and ground to 10 microns. The wellknown phenomenons at the bone cement border were found too. Direct bone cement contact is about 5%. The 4 studied femura show a higher porosity of cortical bone as controls. The loss of cortical bone is up to 40% after 55 months. There is a correlation between new load situation and the localisation of bone loss.  相似文献   
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The results with two new enucleation prothesis made of Bioverit are presented. After unilateral enucleation 14 rabbits received bioreactive, 14 rabbits biocompatible and 9 rabbits nylon prostheses. Implantation periods: 1-13 months. The tissue surrounding of the prostheses was studied histologically, the ceramic electron microscopically. Of 28 ceramic prostheses, 26 were adapted very well. Bioverit ist excellently suited as orbital prosthetic material, even half-open implants are possible.  相似文献   
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BACKGROUND: Relatively few studies have been conducted linking decreasing intraocular pressure (IOP) to preservation of visual field. This investigation was conducted to determine if this link could be made and to compare the long-term effect of two ocular hypotensive agents on preservation of visual field. METHODS: In an observer-masked study, 189 patients with primary open-angle glaucoma received either timolol or pilocarpine by random allocation. The dose of antiglaucoma agent was increased from 0.25% to 0.5% twice daily for timolol or from 2% to 4% four times daily for pilocarpine if the initial IOP response was inadequate. After an on-treatment baseline, visual fields were followed every 4 months for 2 years using the Octopus program 32. RESULTS: Compared with timolol, significantly more patients receiving pilocarpine discontinued use because of inadequate IOP control (P < or = 0.01). By comparing the mean visual field scores, it can be seen that the pilocarpine group had a significantly worse score at all timepoints from month 4 to month 24. The pilocarpine group also had a greater mean number of test loci with decreased sensitivity of 5 or more decibels (dB) at all timepoints. The mean within-patient regression slope for timolol was 0.01 dB/month and for pilocarpine was -0.06 dB/month (P < 0.01). The study has shown that over a 2-year period, patients treated with pilocarpine 2% or 4% four times daily experienced a significantly greater visual field deterioration than that seen in patients receiving either 0.25% or 0.5% timolol twice daily. CONCLUSION: Although these data do not support a link between lowering of IOP and visual field preservation, treatment with timolol was associated with significantly less visual field loss than treatment with pilocarpine.  相似文献   
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A new analogue of recombinant human growth hormone (hGH), hGH des(1–6,14) was expressed in Escherichia coli, refolded and purified to homogeneity. The mutation decreased the hormone's ability to bind lactogenic and somatogenic receptors through its site 1, and almost completely abolished its ability to bind these receptors through site 2, as evidenced by both binding and gel-filtration experiments. More specifically, the binding to prolactin receptors (PRLRs) from various species or their soluble recombinant extracellular domains (ECDs) was decreased 1.5–4-fold, whereas the binding to hGH receptor (hGHR) was decreased 10–85-fold. These changes caused an almost total loss of hormone agonistic activity in several in vitro bioassays and subsequently, the hGH des(1–6,14) analogue acquired antagonistic properties. This antagonistic activity was dependent upon modification of site 1. In those cases in which the binding was reduced only slightly, e.g. binding to rabbit PRLRs, hGH des(1–6,14) acted as a strong antagonist, whereas in others in which the binding of site 1 was reduced to a higher degree, such as other PRLRs and, in particular, hGHR, the antagonistic activity was correspondingly weaker. Circular dichroism spectra of the analogue suggested that these changes do not result from a decrease in overall -helix content, but rather from minor local structural modifications at the N-terminus.  相似文献   
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We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed.  相似文献   
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When rural/urban differences are found in health status or health care use, it is often desirable to identify those factors (such as age, social structure, income, etc.) that influence such differences. To this end, researchers often test rural/urban differences in age, social structure, income, etc., for statistical significance. Also, researchers commonly perform multivariate analyses (such as multiple regressions) to examine rural-urban differences in the influence of various independent variables on the dependent variable of interest. Frequently, researchers discover: (1) statistically significant rural/urban differences in the independent variables (such as age, social structure, income, etc.) and (2) statistically significant rural/urban differences in the effects of these independent variables (i.e., statistically significant rural/urban differences in regression coefficients). The analysis typically stops here, without addressing the relative contributions of (1) and (2) to the rural/urban differences in the dependent variable. This paper argues that the relative contributions of (1) and (2) have important implications for the way policy-makers address rural health problems. This paper presents a method for assessing the relative contributions of differences in the independent variables and differences in regression coefficients to observed differences in the dependent variable, and illustrates the application of the method by analyzing rural/urban differences in the risk of institutionalization.  相似文献   
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