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1.
C Niek van Dijk Ben Willem J. Mol Liesbeth S. L. Lim Rene K. Marti Patrick M. M. Bossuyt 《Acta orthopaedica》1996,67(6):566-570
We prospectively enrolled 160 consecutive patients with inversion trauma of the ankle in a diagnostic protocol that included physical examination within 2 days and at 5 days after trauma, arthrography, stress radiography, and ultrasonography. 135 patients had pathological lateral ligament laxity on the later physical examination or lateral ligament rupture diagnosed on arthrography and they were operated on. 122 of these patients had ligament ruptures.
At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.
Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information. 相似文献
At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.
Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information. 相似文献
2.
Liesbeth Vandenput Fernand Labrie Dan Mellstr?m Charlotte Swanson Thomas Knutsson Ralph Peeker Osten Ljunggren Eric Orwoll Anna L Eriksson Jan-Erik Damber Claes Ohlsson 《Journal of bone and mineral research》2007,22(2):220-227
Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men. 相似文献
3.
Summary MRI-autopsy correlation in a case of gliomatosis cerebri suggests that poor gray-white matter demarcation on MRI may be sign of neoplastic infiltration. The extent of infiltration is imperfectly assessed by current imaging modalities. 相似文献
4.
Horst Claassen Frank Hornberger Katharina Scholz-Ahrens Michael Schünke Jürgen Schrezenmeir Bodo Kurz 《Annals of anatomy》2002,184(2):141-148
Clinical observations have suggested that estrogens are involved in the pathogenesis of postmenopausal osteoarthritis (OA). However, positive and negative associations between the incidence of OA and serum estrogen concentrations have been reported. In contrast to this, osteoporosis is regarded as a disease with a strong estrogen-dependent component. Moreover, there is an interaction between estrogen and calcium deficiency: calcium supplementation potentiates the effect of estrogen therapy. The present study was designed to investigate how estrogen deficiency affects the articular cartilage depending on calcium supply. The distribution of different types of glycosaminoglycans and collagens can be used as an indicator for extracellular matrix changes induced by estrogen deficiency. Different levels of dietary calcium were therefore fed to intact and ovariectomized G?ttingen miniature pigs for one year before articular cartilage was harvested. The histochemical staining for heavy sulfated glycosaminoglycans in the extracellular matrix of ovariectomized miniature pigs, especially of those fed with a low calcium diet, was stronger in comparison to intact animals. In intact animals type II-collagen was immunodetected in all zones of unmineralized and mineralized articular cartilage, while immunostaining for this protein was negative to weak in the deep radiated fiber zone of ovariectomized minipigs. These results suggest that the synthesis of heavy sulfated glycosaminoglycans and immunohistochemically detectable type II-collagen is possibly influenced by estrogen deficiency. In conclusion, under estrogen deficiency, the extracellular matrix of articular cartilage underwent similar changes to those observed in physiologically aging cartilage where keratan sulfate is increased as a heavy sulfated glycosaminoglycan. 相似文献
5.
van Eden W Hauet-Broere F Berlo S Paul L van der Zee R de Kleer I Prakken B Taams L 《International reviews of immunology》2005,24(3-4):181-197
Immunization with microbial or mammalian stress proteins or heat-shock proteins in models of experimental autoimmunity has been observed to lead to increased disease resistance. Furthermore, such immunization has been proposed to result in the induction and expansion of T cells that suppress disease upon transfer. Comparisons of microbial heat-shock proteins with other conserved immunogenic proteins of bacterial origin have indicated a unique capacity for heat-shock proteins to induce a regulatory phenotype in T cells, such as reflected by the production of IL10. Also, studies in children with chronic arthritis have indicated that T-cell responses to heat-shock proteins are associated with a benign course of the disease and with remission. Furthermore, in patients, heat-shock-protein-(HSP-) activated T cells were shown to display regulatory phenotypes consistent with CD4+ CD25+ T regulatory cells. 相似文献
6.
Pennings RJ Te Brinke H Weston MD Claassen A Orten DJ Weekamp H Van Aarem A Huygen PL Deutman AF Hoefsloot LH Cremers FP Cremers CW Kimberling WJ Kremer H 《Human mutation》2004,24(2):185
Usher syndrome type II (USH2) is characterised by moderate to severe high-frequency hearing impairment, progressive visual loss due to retinitis pigmentosa and intact vestibular responses. Three loci are known for USH2, however, only the gene for USH2a (USH2A) has been identified. Mutation analysis of USH2A was performed in 70 Dutch USH2 families. Ten mutations in USH2A were detected, of which three are novel, c.949C>A, c.2242C>T (p.Gln748X) and c.4405C>T (p.Gln1468X). Including 9 previously published Dutch USH2a families, estimates of the prevalence of USH2a in the Dutch USH2 population were made. Mutations were identified in 62% of the families. In 28% both mutated alleles were identified, whereas in 34% the mutation in only one allele was found. It is estimated that about 28% of the Dutch USH2 families have a different causative gene. Analysis of deduced haplotypes suggests that c.1256G>T (p.Cys419Phe) is a Dutch ancestral mutation, occurring in 16% of the alleles. 相似文献
7.
Enhanced Immunological Memory Responses to Listeria monocytogenes in Rodents, as Measured by Delayed-Type Hypersensitivity (DTH), Adoptive Transfer of DTH, and Protective Immunity, following Lactobacillus casei Shirota Ingestion
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R. de Waard E. Claassen G. C. A. M. Bokken B. Buiting J. Garssen J. G. Vos 《Clinical and Vaccine Immunology : CVI》2003,10(1):59-65
We have investigated the effect of orally administered Lactobacillus casei Shirota (L. casei) on immunological memory, as measured by delayed-type hypersensitivity (DTH) and acquired cellular resistance (ACR). The studies were performed in animal models in which the animals were rendered immune by a primary Listeria monocytogenes infection. It was shown that orally administered viable L. casei, and not heat-killed L. casei, enhanced significantly the antigen-specific DTH at 24 and 48 h in Wistar rats, Brown Norway rats, and BALB/c mice in a time- and dose-dependent fashion. L. casei had to be administered at least 3 days prior to the DTH assay at a daily dose of 109 CFU in order to induce significant effects. Long-term administration of 109 CFU of viable L. casei resulted in enhanced ACR, as demonstrated by reduced L. monocytogenes counts in the spleen and liver and diminished serum alanine aminotransferase activity after reinfection. Enhancement of cell-mediated immunological immune responses by L. casei was further established in an adoptive transfer study. Naïve recipient BALB/c mice, which were infused with nonadherent, immunized spleen cells from L. casei-fed donor BALB/c mice, showed significantly enhanced DTH responses at 24 and 48 h compared to recipient mice which received spleen cells from control donor mice. In conclusion, orally administered L. casei enhanced cell-mediated immunological memory responses. The effects relied on lactobacillus dose and viability as well as timing of supplementation and, further, appeared to be independent of host species or genetic background. 相似文献
8.
Folic acid and homocysteine affect neural crest and neuroepithelial cell outgrowth and differentiation in vitro. 总被引:3,自引:0,他引:3
Marit J Boot Régine P M Steegers-Theunissen Robert E Poelmann Liesbeth Van Iperen Jan Lindemans Adriana C Gittenberger-de Groot 《Developmental dynamics》2003,227(2):301-308
The beneficial effect of additional folic acid in the periconceptional period to prevent neural tube defects, orofacial clefts, and conotruncal heart defects in the offspring has been shown. Folate shortage results in homocysteine accumulation. Elevated levels of homocysteine have been related to neural tube defects. We studied the behavior of neuroepithelial cells and cranial and cardiac neural crest cells in vitro. Neural tube explants were cultured for 24 and 48 hr in medium after addition of folic acid and/or homocysteine. Folic acid addition increased neuroepithelial cell outgrowth and increased neural crest cell differentiation into nerve and smooth muscle cells. Addition of homocysteine increased neural crest cell outgrowth and migration from the neural tube and inhibited neural crest cell differentiation. Our findings suggest that neural tube defects caused by folate deficiency and hyperhomocysteinemia develop due to increased neuroepithelial to neural crest cell transformation. This increased transformation leads to a shortage of neuroepithelial cells in the neural tube. Defects in orofacial and conotruncal development are explained by abnormal differentiation of neural crest cells in the presence of high homocysteine concentrations. Our findings supports a critical role for folic acid and homocysteine in the development of neural tube defects and neural crest related heart malformations. 相似文献
9.
Seven Etruscan skulls were found in Corneto Tarquinia in the years 1881 and 1882 and were given as present to Rostock's anatomical collection in 1882. The origin of the Etruscans who were contemporary with the Celts is not yet clear; according to Herodotus they had emigrated from Lydia in Asia Minor to Italy. To fit the Etruscan skulls into an ethnological grid they were compared with skeletal remains of the first thousand years B.C. E. All skulls were found to be male; their age ranged from 20 to 60 years, with an average age of about thirty. A comparison of the median sagittal outlines of the Etruscan skulls and the contemporary Hallstatt-Celtic skulls from North Bavaria showed that the former were shorter and lower. Maximum skull length, minimum frontal breadth, ear bregma height, bizygomatical breadth and orbital breadth of the Etruscan skulls were statistically significantly less developed compared to Hallstatt-Celtics from North Bavaria. In comparison to other contemporary skeletal remains the Etruscan skulls had no similarities in common with Hallstatt-Celtic skulls from North Bavaria and Baden-Württemberg but rather with Hallstatt-Celtic skulls from Hallstatt in Austria. Compared to chronologically adjacent skeletal remains the Etruscan skulls did not show similarities with Early Bronze Age skulls from Moravia but with Latène-Celtic skulls from Manching in South Bavaria. Due to the similarities of the Etruscan skulls with some Celtic skulls from South Bavaria and Austria, it seems more likely that the Etruscans were original inhabitants of Etruria than immigrants. 相似文献
10.
Cellular basis of an auto-anti-allotypic mechanism for the maintenance of chronic allotype suppression in the rabbit.
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Immunocytochemical identification of antibody-forming cells (AFCs) in situ was used to test the hypothesis that the maintenance of chronic allotype suppression in heterozygous rabbits is the result of an autoimmune B-cell-mediated response. Appreciable numbers of B cells with antibody activity directed against the suppressed allotypic determinant were found in spleen and bone marrow sections of all chronically suppressed rabbits examined. Appropriate double-staining was used to determine that such cells were of the non-suppressed allotype. These cells were indistinguishable from anti-allotypic AFCs found in larger numbers in spleens of normal heterozygous rabbits that had been immunized against a heterologous allotypic determinant. Auto-anti-allotypic AFCs were not found in suppressed rabbits less than 8 week old, nor were they found in normal (non-suppressed) heterozygous rabbits or chimeric rabbits formed by the injection of histocompatible but allotype-mismatched lymphoid cells at birth. The findings reported here support the hypothesis that the long-term maintenance of allotype suppression in the rabbit may result from the suppressive activities of autoimmune B cells. It is suggested that the suppression of an allotype during the first few weeks of life could result in a loss of tolerance to a self-determinant. The kinetics of auto-anti-AFC production support this idea in showing that such cells are generated following the decline of the antibody used to induce suppression. The triggering event may be the emergence of B cells expressing the previously suppressed gene product. 相似文献