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排序方式: 共有1527条查询结果,搜索用时 31 毫秒
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Gesine Respondek MD Max-Joseph Grimm MD Ines Piot MD Thomas Arzberger MD Yaroslau Compta MD Elisabet Englund MD Leslie W. Ferguson MD Ellen Gelpi MD Sigrun Roeber MD Armin Giese MD Murray Grossman MD David J. Irwin MD Wassilios G. Meissner MD PhD Christer Nilsson MD Alexander Pantelyat MD Alex Rajput MD John C. van Swieten MD Claire Troakes PhD MSc Günter U. Höglinger MD for the Movement Disorder Society–Endorsed Progressive Supranuclear Palsy Study Group 《Movement disorders》2020,35(1):171-176
63.
Venous thromboembolism in trauma: a local manifestation of systemic hypercoagulability? 总被引:9,自引:0,他引:9
BACKGROUND: The purpose of this study was to evaluate the relative importance of systemic hypercoagulability, preexisting and acquired risk factors, and specific injury patterns in the development of venous thromboembolism (VTE) after injury. METHODS: Injured patients with an Injury Severity Score > or = 15 were followed with lower extremity venous duplex ultrasonography, prothrombin fragment 1 + 2, and quantitative D-dimer levels at 1 and 3 days and then weekly until discharge. RESULTS: Among 101 patients with a mean Injury Severity Score of 27.3 +/- 10.5 followed for 12.4 +/- 8.7 days, 28 (27.7%) developed a lower extremity thrombosis, 2 (1.9%) sustained a pulmonary embolism, and 1 (0.9%) had a symptomatic upper extremity thrombosis. Although admission fragment 1 + 2 and D-dimer levels were elevated in 81.4% and 100% of patients, respectively, mean levels were not significantly different in those with or without VTE. VTE was more common (p < 0.05) among those with obesity, age > 40 years, immobilization for > 3 days, spine fractures, and lower extremity fractures. However, only obesity (p = 0.004) and immobilization > 3 days (p = 0.05) were independent predictors of VTE in a multivariate analysis. CONCLUSION: Although elevated in seriously injured patients, neither markers of activated coagulation nor specific injury patterns are predictive of VTE. Associations with immobilization and obesity suggest that VTE after injury is a systemic hypercoagulable disorder with local manifestations of thrombosis related to lower extremity stasis. 相似文献
64.
Meissner MH 《Seminars in vascular surgery》2001,14(3):215-221
Venous duplex ultrasonography is now the diagnostic test of choice for the diagnosis of deep venous thrombosis (DVT) at many institutions. In the research setting, the ability to serially evaluate thrombi localized to specific venous segments has shown the importance of recurrent thrombotic events and recanalization in the natural history of acute DVT. In addition, its availability and noninvasive nature have led increasingly to the use of serial venous ultrasound examinations in the clinical management of acute DVT. Unfortunately, there is little evidence to support the use of follow-up ultrasonography for many of these purposes. Based on the limited evidence available, follow-up ultrasound examinations appear to be warranted only in patients with isolated calf vein thrombosis and contraindications to conventional anticoagulation, patients with recurrent symptoms, and to establish a baseline after completion of therapy in patients at risk for recurrence. In contrast, the anticoagulant management of acute DVT should be guided by the results of clinical trials, and currently available evidence provides no basis for using ultrasonography to guide the duration of anticoagulation. Therefore, if therapy is based on guidelines derived from clinical trials, there are few indications for the noninvasive follow-up of DVT during anticoagulant treatment in the absence of new symptoms. 相似文献
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Giulia Renieri Lars Choritz Rita Rosenthal Susann Meissner Norbert Pfeiffer Hagen Thieme 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2008,246(8):1107-1115
BACKGROUND: Endothelin-1 (ET-1) is known to induce contraction of trabecular meshwork (TM) and is probably involved in the pathogenesis of glaucoma. Calcium (Ca(2+))-independent contraction has been shown in TM, and its inhibition may represent an interesting way of influencing outflow facility, and thus intraocular pressure (IOP). This study investigates the role of ET-1 and its receptors ET-A and ET-B (ET-AR and ET-BR) in TM Ca(2+)-independent contractility. METHODS: Isometric tension measurements of bovine TM (BTM) strips were performed using a force-length transducer system. Intra- and extracellular Ca(2+) buffering was achieved by means of EGTA and BAPTA-AM. Under Ca(2+)-free conditions, ET-1-induced contractility of TM was assessed also in the presence of the specific inhibitors for ET-AR and ET-BR, BQ123 and BQ788 respectively. In order to clarify the intracellular mediators of Ca(2+)-independent contractility induced by ET-1, TM contraction was further measured in the presence of Y-27632, a selective inhibitor of Rho-associated kinases (ROCKs). The expression of ROCK1 and of its activating protein RhoA in BTM cells was investigated using western blot analysis. RESULTS: ET-1 induced a significant contraction of native BTM after intra- and extracellular Ca(2+)-depletion (45% +/- 8% of the maximally inducible contraction). Both endothelin receptor inhibitors BQ123 and BQ788 significantly reduced TM Ca(2+)-independent contraction in response to ET-1 (8.4 +/- 3.3% and 20.3 +/- 4.8% respectively). In the presence of the ROCK inhibitor Y-27632, ET-1-induced contraction of TM under Ca(2+)-free conditions was almost completely abolished (4.3% +/- 1.7%, p < 0.001). A clear signal for RhoA at 24 kDa and ROCK1 at 160 kDa could be detected in lysates of native tissue and cultured BTM cells with western blot. CONCLUSIONS: This study shows evidence that a significant portion of ET-1-induced contraction of TM is Ca(2+)-independent. In this contraction pathway, both ET-AR and ET-BR are involved with RhoA and its kinases as intracellular mediators. Ca(2+)-independent contraction of TM in response to ET-1 may represent a specific target to modulate IOP. 相似文献
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The clinical challenge lies in recognizing cases not fully meeting the syndrome's diagnostic criteria and those that strongly resemble a variety of infectious and reactive disorders. Prompt treatment with high-dose intravenous immune globulin in combination with aspirin can significantly reduce the frequency and severity of cardiovascular complications. 相似文献
70.
Secretory immunoglobulin A (S-IgA) is an essential part of local immune system of female genital tract. Accordingly the estimation of S-IgA in female genital secretions is important for judgement of immunologic problems in female genital tract. The estimation of S-IgA was carried out by means of an antiserum against human secretory component (anti SC) and S-IgA standard. It was used the single radial immunodiffusion according to Mancini and co-workers. Our results refer to changes in the quantity of S-IgA locally produced in the mucous membranes of female genital tract correlated to the menstrual cycle. The essential results are a decrease of S-IgA in midcycle in cervical mucus and vaginal fluids as well as of fertile and sterile patients. 相似文献