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31.
Fixation of syndesmotic ruptures in 38 patients with a malleolar fracture: a randomized study comparing a metallic and a bioabsorbable screw 总被引:4,自引:0,他引:4
OBJECTIVES: To compare the performance of a metallic and a biodegradable screw in the fixation of tibia-fibula syndesmotic ruptures. DESIGN: A randomized, prospective, and blinded study. SETTING: Central hospital, Department of Surgery. PATIENTS: Forty consecutive patients with a clinically verified syndesmotic rupture in association with a malleolar fracture, of whom 38 completed the study. INTERVENTION: After syndesmosis rupture was diagnosed, implant selection was performed intraoperatively by a strict randomization with sealed envelopes. Eighteen patients were treated with a metallic screw, and 20 with a bioabsorbable polylevolactic acid screw. The metallic screws were removed in a second operation at 8 weeks postoperatively. All patients had a treatment-blinded clinical and radiographic control after a mean follow-up of 35 (range 17-51) months. MAIN OUTCOME MEASURES: Return to previous physical activity level, evaluation of ankle stability, range of motion, circumference of the ankle, and a radiographic evaluation of both ankles including a measure of the talocrural, medial joint, and syndesmotic space widths. RESULTS: More patients with a polylevolactic acid screw returned to their previous activity level, and there was less swelling in the ankles of these patients, but joint motion was similar between the groups. The mean values of syndesmotic and medial joint spaces were significantly higher in the radiographs of the operated ankles when compared to the uninjured ankle, but there was not a correlation to the type of screw used. CONCLUSIONS: Polylevolactic acid screws worked as well, or slightly better than, metallic ones in syndesmosis fixation in patients with an ankle fracture. 相似文献
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33.
To study the relation between sodium transport in airway epithelium and postnatal pulmonary adaptation, we measured nasal potential difference at 1 to 4 hours and lung compliance at 21 to 48 hours after birth in 20 healthy infants. Sodium transport correlated with lung compliance ( r 2 = 0.40, P < .003). Airway sodium transport plays a role in postnatal pulmonary adaptation. 相似文献
34.
BACKGROUND: The optimal treatment of diaphyseal fractures of the lower extremities in patients who also have serious chest injuries is not known. PATIENTS AND METHODS: We retrospectively evaluated the effect of an early intramedullary nailing (IMN) of femur or tibia fractures on respiratory function in 61 consecutive polytraumatized patients with unilateral or bilateral pulmonary contusion (thoracic AIS=3) admitted to our trauma intensive care unit between January 2000 and June 2001. 27 patients had a diaphyseal fracture of at least one long bone of the lower extremity, which was treated with IMN within 24 hours of admission. RESULTS: We found no difference between patients with or without a lower extremity fracture regarding the length of ventilator treatment, oxygenation ratio (PaO2/FiO2) or in the incidence of acute respiratory distress syndrome (ARDS), pneumonia, multi-organ failure or mortality. INTERPRETATION: In this retrospective study, IMN of a long bone fracture in a patient with multiple injuries and with a coexisting pulmonary contusion did not impair pulmonary function or outcome. 相似文献
35.
Deletion of laminin-8 results in increased tumor neovascularization and metastasis in mice 总被引:7,自引:0,他引:7
Zhou Z Doi M Wang J Cao R Liu B Chan KM Kortesmaa J Sorokin L Cao Y Tryggvason K 《Cancer research》2004,64(12):4059-4063
Laminin-8 (alpha 4 beta 1 gamma 1) is one of the major laminin isoforms expressed in vascular endothelial basement membranes. Here we show that deletion of laminin-8 in mice affects angiogenesis under pathological conditions. Murine tumor models used in laminin alpha 4-deficient mice results in hyperneovascularization and significant promotion of tumor growth and metastasis. The higher tumor growth rates in mutant mice correlate with decreased tumor cell apoptosis. Depletion of laminin alpha 4 chain may alter the structure of vascular basement membranes, leading to increased angiogenesis. Our data suggest that the laminin-8 plays a critical role in the regulation of pathological angiogenesis. 相似文献
36.
37.
New prolyl oligopeptidase inhibitors developed from dicarboxylic acid bis(l-prolyl-pyrrolidine) amides 总被引:1,自引:0,他引:1
Wallén EA Christiaans JA Jarho EM Forsberg MM Venäläinen JI Männistö PT Gynther J 《Journal of medicinal chemistry》2003,46(21):4543-4551
Isophthalic acid bis(l-prolyl-pyrrolidine) amide is a very potent prolyl oligopeptidase inhibitor, but it has a log P value of -0.2, which is very low for a compound targeted to the brain. Therefore, these types of compounds were further modified to improve the structure-activity relationships, with the focus on increasing the log P value. The inhibitory activity against prolyl oligopeptidase from pig brain was tested in vitro. The most promising compounds resulted from replacing the pyrrolidinyl group at the P5 site by cycloalkyl groups, such as cyclopentyl and cyclohexyl groups, and by a phenyl group. These compounds are slightly more potent, and they have a significantly higher log P value. The potency of these compounds was further increased by replacing the pyrrolidinyl group at the P1 site by 2(S)-cyanopyrrolidinyl and 2(S)-(hydroxyacetyl)pyrrolidinyl groups. 相似文献
38.
Distinct patterns of neonatal gut microflora in infants in whom atopy was and was not developing 总被引:22,自引:0,他引:22
Kalliomäki M Kirjavainen P Eerola E Kero P Salminen S Isolauri E 《The Journal of allergy and clinical immunology》2001,107(1):129-134
BACKGROUND: Improved hygiene has altered early microbial exposure by reducing childhood infections, which has been suggested as a cause for the continuously rising prevalence of atopic diseases. On the basis of both intensity and timing of stimulus, it has been hypothesized that exposure to commensal microflora may represent another key protective modulator of immunity against atopy and subsequent atopic diseases. OBJECTIVE: We sought to investigate whether differences in early gut microflora precede the later development of atopic sensitization. METHODS: Intestinal microflora from 76 infants at high risk of atopic diseases were analyzed at 3 weeks and 3 months of age by using conventional bacterial cultivation and 2 culture-independent methods, gas-liquid chromatography of bacterial cellular fatty acids and quantitative fluorescence in situ hybridization of bacterial cells. Infants evincing at least one positive skin prick reaction at 12 months were grouped as atopic subjects, and those without positive reactions were grouped as nonatopic subjects. RESULTS: Atopic sensitization was observed in 22 (29%) of 76 children. At 3 weeks, the bacterial cellular fatty acid profile in fecal samples differed significantly between infants in whom atopy was and was not developing (P =.005). By using fluorescence in situ hydridization, atopic subjects had more clostridia (geometric mean [95% confidence interval]: 9.3 x 10(7) [3.8-22.9 x 10(7)] vs 3.3 x 10(7) [1.8-6.1 x 10(7)], P =.04) and tended to have fewer bifidobacteria (1.8 x 10(9) [0.4-7.6 x 10(9)] vs 6.1 x 10(9) [2.5-14.6 x 10(9)], P =.11) in their stools than nonatopic subjects, resulting in a reduced ratio of bifidobacteria to clostridia (P =.03). The differences were not detected by bacterial cultivation. CONCLUSION: Differences in the neonatal gut microflora precede the development of atopy, suggesting a crucial role of the balance of indigenous intestinal bacteria for the maturation of human immunity to a nonatopic mode. 相似文献
39.
Sirkku Niissalo Jarkko Hietanen Maria Malmström Mika Hukkanen Julia Polak Yrjö T. Konttinen 《Journal of oral pathology & medicine》2000,29(8):361-369
The peripheral nervous system was analysed in the oral mucosa of eight patients with oral lichen planus (OLP), five with a lichenoid reaction (LR) and three with mild chronic inflammation (MCI), by morphometric analysis of nerve fibres containing immunoreactive PGP 9.5, substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), or C-flanking peptide of neuropeptide Y (CPON). Overall nerve fibre density was higher in OLP (P=0.039) and LR (P=0.026) compared with healthy oral mucosa and was compatible with sprouting and collateral formation. In contrast to the innervation visualized with structural nerve fibre-marker PGP 9.5, the densities of neuropeptide-immunoreactive nerves were low in inflamed tissue. This is consistent with depletion via local release. Retraction and local loss of innervation were found in areas coinciding with the most severe inflammation and basal membrane (BM) damage. Interestingly, LR showed a twenty-eight-fold loss of post-ganglionic CPON-ir sympathetic nerve fibres (P=0.044). In LR, CPON-ir innervation was markedly lower than in OLP. Finally, the pattern of innervation in relation to inflammatory cell infiltrates and tissue structures differed between OLP and LR. In conclusion, the peripheral nervous system is implicated in the immunopathogenesis of lichen planus and lichenoid reactions, with a disorder-specific difference in this involvement. 相似文献
40.
Pirjo-Liisa Lukinmaa Jarkko Hietanen Gunnar Warfvinge Juha Sane Susanne Tuominen Vincent Henriksson Åke Larsson 《Journal of oral pathology & medicine》2000,29(4):186-192
Solitary fibrous tumour (SFT) is an uncommon mesenchymal neoplasm rarely located in the oral cavity. To characterize further oral SFT, we describe three new cases. Each tumour originated in the buccal mucosa of a middle-aged/elderly patient. Histological examination showed well-circumscribed tumours with densely cellular areas alternating with hypocellular areas in a variedly collagenous, vascular stroma. Mast cells were abundant. The spindle-shaped, neoplastic cells immunostained strongly for CD34 antigen and vimentin and weakly for bcl-2, but not for epithelial cell markers, alpha-smooth muscle actin, or neurofilament or S-100 proteins. Compatible with the virtual absence of mitoses and of marked nuclear atypia, the overall frequency of proliferating cells expressing Ki-67 was low. The expression of CD34 was useful in the differential diagnosis. The consistent location in the cheek and expansion of one tumour after local trauma does not preclude a traumatic element in the development of oral SFT. 相似文献