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1.

Background

Current blunt cerebrovascular injury (BCVI) grading grossly differentiates injury characteristics such as luminal stenosis (LS) and aneurysmal disease. The effect of increasing degree of LS beyond the current BCVI grading scale on stroke formation is unknown.

Study Design

BCVI over a 3-year period were retrospectively reviewed. To investigate influence of LS beyond the BCVI grading scale within aneurysmal and non-aneurysmal BCVI, grade 2 BCVI were subdivided into BCVI with ≥ 25% and ≤ 50% LS and BCVI with > 50% and ≤ 99% LS. Grade 3 BCVI were subdivided into BCVI with pseudoaneurysm (PSA) without LS and BCVI with PSA and LS. We hypothesized increased LS beyond the current BCVI grade distinctions would be associated with higher rates of stroke formation.

Results

312 BCVI were included, of which 140 were carotid BCVI and 172 vertebral BCVI. Sixteen carotid BCVI underwent endovascular intervention (EI) and 19 suffered a stroke. In carotid BCVI stroke rates increased sequentially with BCVI grade except in grade 3. There was a stroke rate of 12% in grade 1 carotid BCVI, 18% in grade 2, 6% in grade 3, and 31% in grade 4. In subgroup analysis for grade 2 carotid BCVI, BCVI with > 50% and ≤ 99% LS had higher rates of stroke (22% vs. 15%, p?=?0.44) than BCVI with ≥ 25% and ≤ 50% LS. In subgroup analysis of grade 3 carotid BCVI, BCVI with PSA and LS had higher rates of stroke (9% vs. 4%, p?=?0.48) than BCVI with PSA without LS. Higher rates of EI in grade 2 carotid BCVI with > 50% and ≤ 99% LS (22% vs. 5%, p?=?0.14) and grade 3 carotid BCVI with PSA and LS (35% vs. 4%, p?=?0.01) were noted in subgroup analysis.

Conclusion

Higher percentage LS beyond the currently used BCVI grading scale has a non-significantly increased rate of stroke in both aneurysmal and non-aneurysmal BCVI. Grade 3 BCVI with PSA and LS seems to be a high-risk subgroup. Use of EI confounds modern measurement of stroke risk in higher LS BCVI.  相似文献   
2.
Adamantinoma of long bones is one of the rarest of malignant bone tumors; it is commonly located in the middle or lower third of the diaphysis of the tibia. A case with multiple occurrences affecting both the tibia and fibula is presented. En bloc resection with wide operative margins was performed, and a large tibial defect of 23 cm was effectively bridged by a revascularized free fibular flap. At 13 months follow-up, there was no sign of local recurrence or metastasis, and the patient was mobile.  相似文献   
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To investigate the phenotypic consequences of a deranged lymphangiogenesis in relation to tissue fluid accumulation and the possible role of inflammation in the pathogenesis of lymphoedema, we measured determinants of transcapillary fluid filtration and inflammatory mediators in the interstitial fluid in genetically engineered Chy mice, a model for primary congenital lymphoedema (Milroy's disease). Although initial lymphatics were not present in dermis in any of the areas studied (fore paw, hind paw, thigh and back skin) interstitial fluid pressure ( P if), measured with micropipettes, and tissue fluid volumes were significantly increased only in the areas with visible swelling – the fore and hind paw, whereas interstitial colloid osmotic pressure (COPif) was increased in all the skin areas examined. A volume load of 15% of body weight resulted in a more pronounced increase in P if as well as a four-fold increase in interstitial fluid volume in Chy relative to wild-type (wt) mice, showing the quantitative importance of lymphatics for fluid homeostasis during acute perturbations. A similar level of proinflammatory markers in interstitial fluid in early established lymphoedema (3–4 months) in Chy and wt suggests that inflammation does not have a major pathogenetic role for the development of lymphoedema, whereas a reduced level of the immunomodulatory cytokine interleukin (IL)-4 may result in a reduced immunological defence ability and thus lead to the increase in inflammatory cytokines IL-2 and IL-6 observed at a later stage (11–13 months). Our data suggest that primary lymphoedema results in a high interstitial fluid protein concentration that does not induce an interstitial inflammatory reaction per se , and furthermore shows the paramount importance of the initial lymphatics in tissue fluid homeostasis, especially during perturbations of transcapillary fluid balance.  相似文献   
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Zusammenfassung Es wird eine Mikromethylenblaumethode zur quantitativen Bestimmung der Serumascorbinsäure mitgeteilt.Durch vergleichende Untersuchungen mitLund undLiecks Methylenblaumethode wird die Auffassung bekräftigt, daß die Ascorbinsäure ein Vorstadium des C-Vitamins ist.  相似文献   
7.
Children and adolescents who suffer traumatic injuries often seek emergency treatment at a Children's Hospital. Complex injuries to permanent teeth and their periodontium require immediate repositioning and stabilization. Many of these emergencies are treated by pediatric dental residents at the Women and Children's Hospital of Buffalo, Buffalo, New York. The purpose of this study was to characterize these complex injuries of permanent teeth that require emergency treatment in a Children's Hospital. All of the cases of dental trauma which had involved permanent teeth and which had been treated with a splint in 2001 and 2002 were reviewed. There were 79 patients that were between 5 and 19 years of age with twice as many males (54) as females (25). The number of males increased from childhood (5-10 years) to early adolescence (11-15 years) and then decreased rapidly in late adolescence (16-19 years), whereas the number of females decreased steadily with age. Most of the incidents occurred during the summer months (72%), particularly in June and July (42%), and Fridays and Saturdays were the busiest days of the week. Most of the injuries were caused by organized and recreational sporting activities (39%) and accidental falls (33%), followed by interpersonal violence (15%) and a few motor vehicle accidents (7%). The 173 permanent tooth injuries were mostly luxations (62%) or avulsions (20%), with only a few fractures of the alveolar bone (5%) or tooth root (1%). Most of the displacements were lateral luxations (40%) or extrusions (18%) with only a few intrusions (3%). These injuries most commonly afflicted the maxillary central incisors (54%), followed by the maxillary laterals (18%) and mandibular centrals (17%). The emergency treatment that was provided at the Children's Hospital included replantation and repositioning, and the placement of a semi-rigid or flexible splint.  相似文献   
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Biomechanical factors influencing the patterns of pressure distribution at the articular surface and the subchondral bone are suggested to be most important in the pathogenesis of osteoarthritis and ostechondritis dissecans at the knee joint. Besides this, chronic joint instability is another important factor under discussion in the etiology of osteoarthritis of the knee. The patterns of pressure distribution on the femoral condyles of weight-bearing knee joints were investigated in a biostatic cadaver model. The pressure on the femoral condyles was evaluated using pressure-sensitive films with the knee in different physiological joint positions (extension, 15° and 30° flexion) with and without division of either the medial collateral ligament (MCL), the lateral collateral ligament (LCL), the MCL and the anterior cruciate ligament (ACL), or the LCL and the ACL. Results showed that the location of the contact area and peak pressure depended on the joint position and stage of ligament division. Without ligament division the maximum peak pressure was always observed on the medial condyle. Only after MCL and combined MCL + ACL division did the lateral condyle show in extension a higher peak pressure than the medial condyle. Division of the LCL and LCL + ACL resulted in an increase in peak pressure on the medial condyle, particularly in flexion. The highest peak pressure of all was measured in the 30° flexion position on the medial condyle after division of the LCL. The lowest at all was found on the lateral condyle in 15° flexion after LCL division. Additional ACL division resulted in only minor further changes. These results are important for the interpretation of clinically observed factors discussed in the etiology of secondary osteoarthritis of the knee and contribute to the theory of mechanical induction of osteoarthritis and osteochondritis dissecans.Presented in part at the 21st Congress of the Austrian Society of Orthopedic Surgery; May 5th–June 1st, 1991 in Linz/Austria  相似文献   
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