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排序方式: 共有8985条查询结果,搜索用时 15 毫秒
81.
Simone Eckstein Rosina Ehmann Abderraouf Gritli Houcine Ben Yahia Manuel Diehl Roman Wlfel Mohamed Ben Rhaiem Kilian Stoecker Susann Handrick Mohamed Ben Moussa 《Emerging infectious diseases》2021,27(7):1964
Free-roaming camels, especially those crossing national borders, pose a high risk for spreading Middle East respiratory syndrome coronavirus (MERS-CoV). To prevent outbreaks, active surveillance is necessary. We found that a high percentage of dromedaries in Tunisia are MERS-CoV seropositive (80.4%) or actively infected (19.8%), indicating extensive MERS-CoV circulation in Northern Africa. 相似文献
82.
Gershon Volpin Roman Pfeifer Jordan Saveski Ilir Hasani Miri Cohen Hans-Christoph Pape 《Journal of Clinical Orthopaedics and Trauma》2021,12(1):72
The principles of fracture management in patients with multiple injuries continue to be of crucial importance. Early treatment of unstable polytraumatized patients with head, chest, abdomen or pelvic injuries, with blood loss followed by immediate fracture fixation (Early Total Care -ETC) may be associated with secondary life threatening posttraumatic systemic inflammatory response syndrome (SIRS). Development of SIRS is typically a function of the type and severity of the initial injury (the “first hit”). Immediate Fracture fixation, using reamed nails or plates, in such unstable patients with multiple injuries is subsequently defined as the “second hit” and may be associated with development of acute respiratory distress syndrome (ARDS) and multiple organ failure (MOF), with relatively high morbidity and mortality.The other alternative for long bone fracture fixation in unstable polytraumatized patients is based on immediate treatment of life threatening conditions related to the injuries, followed by the initial use of minimally invasive modular external frames for long bone fractures and is called Damage Control Orthopedics (DCO) and is widely accepted. In order to refine the DCO concept and to avoid an overuse of external fixation, the “Safe Definitive Surgery” (SDS) concept has been introduced, which is a dynamic synthesis of both strategies (ETC and DCO). The SDS strategy employs clinical parameters and includes repeated assessment of patients. The following paper is going to summarize historical backgrounds and recent concepts in treatment of polytraumatized patients. 相似文献
83.
Rudolph H. Houben Roman Thaler Patricia F. Friedrich Alexander Y. Shin Andre J. van Wijnen Allen T. Bishop 《Transplantation proceedings》2021,53(1):417-426
BackgroundTransplantation of living allogeneic bone segments may permit reconstruction of large defects, particularly if viability is maintained without immunosuppression. Development of a new autogenous osseous blood supply accomplishes this goal in rodent experimental models. This study evaluates potential systemic and local inflammatory responses to this angiogenesis in a large-animal model.MethodsVascularized allogeneic tibia segments were transplanted orthotopically into matched tibial defects in Yucatan minipigs. Microvascular anastomoses of bone nutrient artery and vein were supplemented by intramedullary placement of an autogenous arteriovenous (AV) bundle in group 1. Group 2 served as a no-angiogenesis control. A 3-drug immunosuppression regimen was withdrawn after 2 weeks. During the 20-week survival period, periodic leukocyte counts and inflammatory cytokine levels were measured. Thereafter, osteocyte survival was quantified and transplant rejection graded by histologic examination and quantitative real-time polymerase chain reaction of immunologic markers.ResultsBoth groups developed an initial systemic response, which resolved after 4 to 6 weeks. No differences were seen in blood cytokine levels. Interleukin 2 expression was diminished in group 1 tibiae. As expected, nutrient pedicles had thrombosed without sustained immunosuppression, occluded by intimal hyperplasia. In group 1, angiogenesis from the autogenous AV bundle resulted in significantly less osteonecrosis (P = .04) and fibrosis (P = .02) than group 2 allotransplants.ConclusionsSystemic immune responses to large-bone allotransplants were not increased by generation of an autogenous osseous blood supply within porcine tibial bone allotransplants. Implanted AV bundles diminished inflammation and fibrosis and improved bone viability when compared to no-angiogenesis controls. 相似文献
84.
Jana Hudcova Syed Talha Qasmi Robin Ruthazer Ahsan Waqas Syed Basit Haider Roman Schumann 《Transplantation proceedings》2021,53(1):119-123
PurposeWe examined the role of obesity and intraoperative red blood cell (RBC) and platelet transfusion in early allograft dysfunction (EAD) following liver transplantation (LT).MethodsThis is a retrospective analysis of 239 adult deceased-donor LT recipients over a 10-year period. EAD was defined by Olthoff’s criteria. Data collection included donor (D) and recipient (R) age, body mass index (BMI) ≥ 35 kg/m2, diabetes mellitus, allograft macrosteatosis, and intraoperative (RBC) and platelet administration. We employed logistic regression to evaluate associations of these factors with EAD. Results are presented as odds ratios (OR) and 95% confidence intervals (CI) with corresponding P values. A P ≤ .05 was considered statistically significant.ResultsEAD occurred in 85 recipients (36%). Macrosteatosis data were available for 199 donors. In the multivariate analyses, BMI-D ≥ 35 kg/m2 increased the odds of developing EAD by 156% in the entire cohort (OR 2.56, 95% CI 1.09-6.01) and by 187% in recipients with macrosteatosis data (n = 199, OR 2.87, 95% CI 1.15-7.15). Each unit of RBCs increased the odds for EAD by 8% (OR 1.08, 95% CI 1.02-1.14) and, for the subgroup of 238 recipients with macrosteatosis data, by 9% (OR 1.09, 95% CI 1.02-1.16).ConclusionWe found a significant independent association of donor obesity and intraoperative RBC transfusion with EAD but no such association for platelet administration, MELD score, age, recipient obesity, and diabetes. 相似文献
85.
Alex M. Hollenberg Noorullah Maqsoodi Amy Phan Aric Huber Ayodeji Jubril Avionna L. Baldwin Noriaki Yokogawa Roman A. Eliseev Addisu Mesfin 《The spine journal》2021,21(7):1205-1216
BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration. 相似文献
86.
Lucie Bryndová Michal Bar Roman Herzig Robert Mikulík Jiří Neumann Daniel Šaňák Ondřej Škoda David Školoudík Daniel Václavík Aleš Tomek 《Health policy (Amsterdam, Netherlands)》2021,125(4):520-525
This article describes policy processes that have led to the re-organisation of stroke care in the Czech Republic since 2011, which has been part of a broader process of care concentration in several medical fields. Currently, stroke care is provided by 13 Comprehensive and 32 Primary Stroke Centres. The paper explains factors that supported the reform implementation, reviews implications, and discusses future challenges.Mandatory reporting of quality indicators, the introduction of a benchmarking system, integration with pre-hospital emergency care, and the introduction of countrywide patient triage have supported more timely treatment for stroke patients and better quality of care. Data from the Stroke Care Quality Indicators of the Czech Stroke Society show positive trends in many areas: the number of patients treated with intravenous thrombolysis quadrupled in eight years, with 26.4 % of all acute stroke patients receiving thrombolysis in 2018. Czech Republic now ranks third in Europe in the number of thrombolysis per population and second in the number of mechanical thrombectomies per population. The Czech experience provides an example of positive outcomes of concentrated stroke care, while highlighting the importance of proper implementation processes. In particular, it is essential to involve stakeholders and to provide reputational incentives through continuous benchmarking. 相似文献
87.
D. P. Wolfer Roman J. Giger Marijana Stagliar Peter Sonderegger Hans-Peter Lipp 《Anatomy and embryology》1998,197(3):177-185
TAG-1/axonin-1 is a neuronal cell adhesion molecule of the immunoglobulin superfamily. It is predominantly expressed during
neural development and has been reported to be involved in axonal growth and pathfinding. Here, the expression of TAG-1/axonin-1
was investigated anatomically in the adult mouse brain by in situ hybridization using digoxigenin-labeled cRNA probes. Low
levels of TAG-1/axonin-1 could be detected in cerebellar granule cells, in tufted and mitral cells of the olfactory bulb,
and in pyramidal cells of area CA1 and CA3 of the hippocampus. We suspect that the expression of TAG-1/axonin-1 in these structures
of the adult brain may serve neural plasticity.
Accepted: 8 September 1997 相似文献
88.
89.
90.
Nuclear industry family study:methods and description of a United Kingdom study linking occupational information held by employers to reproduction and child health
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Maconochie N Doyle P Roman E Davies G Smith PG Beral V 《Occupational and environmental medicine》1999,56(12):798-808
OBJECTION: To describe the methods used in the nuclear industry family study for which a comprehensive database has been assembled that links employment in the nuclear industry and dosimetry records to information on employees'' reproductive health and the health of their children. To discuss the response rates and characteristics of the study population. METHODS: Occupational cohort design leading to a retrospective cohort study of reproductive outcomes reported by 46 396 current and former employees of both sexes in the nuclear industry. Employees of nuclear establishments in the United Kingdom operated by the Atomic Energy Authority, the Atomic Weapons Establishment, and British Nuclear Fuels were surveyed with postal questionnaires ot collect information on pregnancies, children,and periods of infertility. Information on employment and monitoring for ionising radiation was supplied by the employing nuclear authority and was linked to pregnancies and periods of infertility with unique personal identification numbers. RESULTS: The design and completion of this study resulted in high quality data on a representative population of the Atomic Energy Authority, Atomic Weapons Establishment, and British Nuclear Fuels workforces. The response to the survey was extremely good (82% for male workers and 88% for female workers, excluding undelivered questionnaires), and a unique relational database has been created which will enable infertility, pregnancy, and child health outcomes to be examined with respect to the employment and radiation monitoring characteristics of parents. CONCLUSION: This is the first United Kingdom study to link detailed reproductive history data to occupational information held by employers. The methods developed for the study were found to be feasible and successful. The design can be adapted for other investigations of reproductive hazards to men and women in the workplace and is currently in use to survey over 100 000 armed forces personnel in an investigation of reproductive outcome among veterans of the Gulf war. 相似文献