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21.
Ley  K; Linnemann  G; Meinen  M; Stoolman  LM; Gaehtgens  P 《Blood》1993,81(1):177-185
Leukocyte rolling in venules is inhibited by several sulfated polysaccharides, by antibodies to the leukocyte adhesion receptor L- selectin (LECAM-1), and by recombinant soluble L-selectin. The sulfated fucose polymer fucoidin and the polyphosphomannan PPME bind to L- selectin and inhibit L-selectin-mediated lymphocyte adhesion to lymph node high endothelial venules (LN-HEV). We investigated whether fucoidin and PPME also inhibit leukocyte rolling. Rolling leukocyte flux was determined by intravital microscopy in 47 venules (diameter 21 to 50 microns) of the rat mesentery with and without micro-infusion of each reagent through 8-microns glass micropipettes. Micro-infusion (1 mg/mL) or intravenous (IV) injection (25 mg/kg) of fucoidin, but not vehicle, reduced leukocyte rolling by greater than 90%. The half- effective concentration was approximately 2.5 micrograms/mL. Stroboscopic fluorescence video microscopy showed that fucoidin decreased the fraction of rolling leukocytes from 44% of all leukocytes passing the venules in control to less than 1%. PPME micro-infusion (1 mg/mL) or IV injection (14 mg/kg) did not reduce leukocyte rolling. Hence, leukocyte rolling differs from lymphocyte homing with respect to the effect of PPME. This may be related to fucoidin binding to L- selectin with greater affinity than PPME. Alternatively, inflamed venular endothelium may express a ligand for L-selectin different from that constitutively expressed on LN-HEV.  相似文献   
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The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.  相似文献   
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Background

The BIG score (Admission base deficit (B), International normalized ratio (I), and Glasgow Coma Scale (G)) has been shown to predict mortality on admission in pediatric trauma patients. The objective of this study was to assess its performance in predicting mortality in an adult trauma population, and to compare it with the existing Trauma and Injury Severity Score (TRISS) and probability of survival (PS09) score.

Materials and methods

A retrospective analysis using data collected between 2005 and 2010 from seven trauma centers and registries in Europe and the United States of America was performed. We compared the BIG score with TRISS and PS09 scores in a population of blunt and penetrating trauma patients. We then assessed the discrimination ability of all scores via receiver operating characteristic (ROC) curves and compared the expected mortality rate (precision) of all scores with the observed mortality rate.

Results

In total, 12,206 datasets were retrieved to validate the BIG score. The mean ISS was 15 ± 11, and the mean 30-day mortality rate was 4.8%. With an AUROC of 0.892 (95% confidence interval (CI): 0.879 to 0.906), the BIG score performed well in an adult population. TRISS had an area under ROC (AUROC) of 0.922 (0.913 to 0.932) and the PS09 score of 0.825 (0.915 to 0.934). On a penetrating-trauma population, the BIG score had an AUROC result of 0.920 (0.898 to 0.942) compared with the PS09 score (AUROC of 0.921; 0.902 to 0.939) and TRISS (0.929; 0.912 to 0.947).

Conclusions

The BIG score is a good predictor of mortality in the adult trauma population. It performed well compared with TRISS and the PS09 score, although it has significantly less discriminative ability. In a penetrating-trauma population, the BIG score performed better than in a population with blunt trauma. The BIG score has the advantage of being available shortly after admission and may be used to predict clinical prognosis or as a research tool to risk stratify trauma patients into clinical trials.  相似文献   
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Purpose.?To determine whether foot and leg problems are independently associated with functional status in a community sample of older people after adjusting for the influence of socio-demographic, physical and medical factors.

Method.?Data were analysed from the Health Status of Older People project, a population-based study involving a random sample of 1000 community-dwelling people aged 65?–?94 years (533 females, 467 males, mean age 73.4 years?±?5.87). A structured interview and brief physical examination were used to investigate the associations between self-reported foot and leg problems and functional status. Functional status was assessed using: (i) timed ‘Up & Go’ test, (ii) self-reported difficulty climbing stairs, (iii) self-reported difficulty walking one kilometer, (iv) self-reported difficulty performing instrumental activities of daily living (IADLs), and (v) self-reported history of one or more falls in the previous 12 months. These associations were then explored after adjusting for socio-demographic, physical and medical factors.

Results.?Thirty-six percent of the sample reported having foot or leg problems. Univariate analyses revealed that people with foot and leg problems were significantly more likely to exhibit poorer functional status in all parameters measured. After adjusting for socio-demographic, physical and medical factors, foot and leg problems remained significantly associated with impaired timed ‘Up & Go’ performance (OR?=?2.15, 95%CI 1.55?–?2.97), difficulty climbing stairs (OR?=?3.33, 95%CI 1.98?–?5.61), difficulty walking one kilometer (OR?=?3.13, 95%CI 2.09?–?4.69), and history of falling (OR?=?1.73, 95%CI 1.26?–?2.37).

Conclusions.?Foot and leg problems are reported by one in three community-dwelling people aged 65 years and older. Independent of the influence of age, gender, common medical conditions and other socio-demographic factors, foot and leg problems have a significant impact on the ability to perform functional tasks integral to independent living.  相似文献   
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A system for robotically assisted retinal surgery has been developed to rapidly and safely place lesions on the retina for photocoagulation therapy. This system provides real-time, motion stabilized lesion placement for typical irradiation times of 100 ms. The system consists of three main subsystems: a digital-based global tracking subsystem; a fast, analog local tracking subsystem; and a confocal reflectance subsystem to control lesion parameters dynamically. We have reported previously on these individual subsystems. This paper concentrates on the development of a second hybrid system prototype. Considerable progress has been made toward reducing the footprint of the optical system, simplifying the user interface, fully characterizing the analog tracking system, using measurable lesion reflectance parameters to develop a noninvasive method to infer lesion depth, and integrating the subsystems into a seamless hybrid system. These system improvements and progress toward a clinically significant system are covered in detail within this paper. The tracking algorithms and concepts developed for this project have considerable potential for application in many other areas of biomedical engineering.  相似文献   
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MenBvac is an outer membrane vesicle vaccine against systemic meningococcal disease caused by serogroup B Neisseria meningitidis. In this placebo-controlled double-blind study including 374 healthy adolescents, the safety and immunogenicity of a schedule of three primary doses 6 weeks apart followed by a fourth dose a year later were evaluated. Antibody responses to the vaccine strain and heterologous strains (non-vaccine-type strains) and the persistence of these antibodies were measured by the serum bactericidal assay (SBA) and enzyme-linked immunosorbent assay up to 1 year after the last dose. The proportion of subjects with SBA titers of > or = 4 against the vaccine strain increased from 3% prevaccination to 65% after the third dose. Ten months later, this proportion had declined to 28%. The fourth dose induced a booster response demonstrated by 93% of subjects achieving a titer of > or = 4. One year after the booster dose, 64% still showed SBA titers of > or = 4. Cross-reacting antibodies were induced against all heterologous strains tested, although the magnitude of SBA titers differed widely between the different strains. All four doses of MenBvac were safe. Both MenBvac and the placebo had reactogenicity profiles of mild to moderate local and systemic reactions. Pain, the most common reaction, was reported with similar frequencies in both groups. No serious adverse events occurred in the MenBvac group. This study confirmed the good immunogenicity of the primary course of MenBvac and demonstrated prolonged persistence and increased cross-reactivity of functional antibodies elicited by a booster dose.  相似文献   
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