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41.
Annie S.Y. Hui Terence T. Lao Tak Yeung Leung Jelle M. Schaaf Daljit S. Sahota 《International journal of gynaecology and obstetrics》2014
Objective
To examine trends in preterm birth and its relationship with perinatal mortality in Hong Kong.Methods
In a retrospective cohort study, data were reviewed from singletons delivered between 1995 and 2011 at a university teaching hospital. Trends in preterm birth (between 24 and 36 weeks of pregnancy), perinatal mortality, and subtypes of preterm birth (spontaneous, iatrogenic, and following preterm premature rupture of membranes [PPROM]) were examined via linear regression.Results
There were 103 364 singleton deliveries, of which 6722 (6.5%) occurred preterm, including 1835 (1.8%) early preterm births (24–33 weeks) and 4887 (4.7%) late preterm births (34–36 weeks). Frequency of preterm birth remained fairly consistent over the study period, but that of spontaneous preterm birth decreased by 25% (β = –0.83; P < 0.001), from 4.5% to 3.8%. Frequency of preterm birth following PPROM increased by 135% (β = 0.82; P < 0.001), from 0.7% to 1.7%. The perinatal mortality rate decreased from 56.7 to 37.0 deaths per 1000 deliveries before 37 weeks (β = –0.16; P = 0.54). Early preterm birth contributed to 16.0% of all deaths.Conclusion
Although the overall rate of preterm birth in Hong Kong has remained constant, the frequencies of its subtypes have changed. Overall perinatal mortality is gradually decreasing, but early preterm birth remains a major contributor. 相似文献42.
G A van den Berg J M Schaaf G T Nagel A W Teelken F A Muskiet 《Clinica chimica acta; international journal of clinical chemistry》1987,165(2-3):147-154
Capillary gas chromatography and mass fragmentography was used to determine simultaneously 1,3-diaminopropane, putrescine, cadaverine, spermidine, spermine, isoputreanine and putreanine in cerebrospinal fluid. After addition of deuterium labelled analogs and acid hydrolysis, the compounds were isolated by adsorption onto silica and converted into their N-heptafluorobutyryl-methylesters. Quality control data and an application of the method are given. A patient harbouring an astrocytoma was monitored during chemotherapeutic treatment. 相似文献
43.
Wilbrand JF Wilbrand M Schaaf H Howaldt HP Malik CY Streckbein P 《Journal of endodontics》2011,37(6):875-877
Introduction
Embolia cutis medicamentosa (Nicolau syndrome) is a rare iatrogenic event of tissue necrosis after intramuscular or intraarticular application of cristalloid suspensions. Clinically, it presents as a livid discoloration of the skin, local pain, and signs of inflammation.Methods
This article presents the first case of Nicolau syndrome after the endodontic application of calcium hydroxide paste into the distal root canal of tooth 18. The patient presented to the Department for Maxillofacial Surgery and hospitalized for several days.Results
The application of calcium hydroxide paste led to a thrombosis of the inferior alveolar artery and various branches of the maxillary artery. A definite necrosis of the left-side infraorbital skin area and concomitant hypaesthesia of the infraorbital nerve and of the mental nerve were observed.Conclusions
Calcium hydroxide paste is appropriate for the medicamentous treatment of root canals, but is not suitable to stanch bleeding from periapical arteries. 相似文献44.
Lymphangiomas in children: MR imaging 总被引:9,自引:0,他引:9
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence. 相似文献
45.
Paul C. Willems Leon Elmans Patricia G. Anderson Wilco C. H. Jacobs Dick B. van der Schaaf Marinus de Kleuver 《European spine journal》2006,15(10):1487-1494
The results of lumbar fusion in chronic low back pain (LBP) patients vary considerably, and there is a need for proper patient selection. Lumbosacral orthoses have been widely used to predict outcome, however, with little scientific support. The aim of the present study was to determine the value of a pantaloon cast test in selecting chronic LBP patients for lumbar fusion or conservative management. First, a systematic review of the literature was carried out in which two independent reviewers identified studies in Medline, Cochrane and Current Contents databases. Three papers met the selection criteria. In the only study with a control group, a significantly better outcome after fusion compared to conservative treatment was found in patients who reported significant pain relief while in a cast (i.e. a positive cast test). The results of lumbar fusion, however, were not significantly different for patients with a positive and those with a negative cast test. In addition to the review, a clinical cohort study of 257 LBP patients, who had been allocated to either lumbar fusion or conservative management by a temporary external transpedicular fixation trial, was performed. Prior to allocation, all had undergone a pantaloon cast test. Patients with no history of prior spine surgery and with a positive pantaloon cast test had a better outcome after lumbar fusion than those treated conservatively (P = 0.002, χ
2 test). In patients with previous spine operations the outcomes were poor and the test was of no value. From the literature and the present patient cohort, it was concluded that only in chronic LBP patients without prior spine surgery, a pantaloon cast test with substantial pain relief suggests a favorable outcome of lumbar fusion compared to conservative management. The test has no value in patients who have had previous spine surgery. 相似文献
46.
Donor‐specific anti‐HLA antibodies are not associated with nonanastomotic biliary strictures but both are independent risk factors for graft loss after liver transplantation 下载免费PDF全文
Anne Claire den Dulk Xiaolei Shi Cornelia. J. Verhoeven Jeroen Dubbeld Frans H. J. Claas Ron Wolterbeek Simone H. Brand‐Schaaf Hein W. Verspaget Arantza Fariña Sarasqueta Luc J. W. van der Laan Herold J. Metselaar Bart van Hoek Jaap Kwekkeboom Dave L. Roelen 《Clinical transplantation》2018,32(2)
Donor‐specific alloantibodies (DSA) have been associated with rejection and shorter graft survival after orthotopic liver transplantation (OLT). We examined the role of DSA in nonanastomotic biliary strictures (NAS) after OLT. Patients receiving first OLT who developed NAS (n = 68) and a control group without NAS (n = 83), with pre‐OLT and 12 months post‐OLT serum samples, were included. DSA were specified using the Luminex single antigen test. Risk factors for NAS and graft survival were analyzed. The presence of preformed DSA was not significantly different between patients with NAS and controls (P = .89). After 12 months, 26.5% of NAS patients and 16.9% of controls had generated de novo DSA (P = .15). Neither de novo class I DSA nor de novo class II DSA were associated with NAS. De novo DSA generally developed after the diagnosis of NAS. Time‐dependent regression analysis identified both NAS (aHR 8.05, CI 3.28 – 19.77, P < .01) and de novo class II DSA (aHR 2.84, CI 1.38 – 5.82, P < .01) as independent risk factors for graft loss. Preformed or de novo DSA were not associated with the development of NAS. However, NAS as well as de novo class II DSA were independent risk factors for graft loss after OLT. 相似文献
47.
Sameh Attia Jörg Wiltfang Philipp Streckbein Jan-Falco Wilbrand Thaqif El Khassawna Katharina Mausbach Hans-Peter Howaldt Heidrun Schaaf 《Journal of cranio-maxillo-facial surgery》2019,47(5):786-791
Purpose
Microvascular fibula flap surgery is a reliable and effective procedure for reconstructing the jaws after tumour surgery. This procedure allows the placement of dental implants after bone consolidation. This study was designed to evaluate the oral, functional, and aesthetic rehabilitation of tumour patients with immediate fibula transfer and dental implants and included assessment of diet, speech, and aesthetics.Materials and methods
The study included 34 patients who underwent ablative tumour surgery and immediate jaw reconstruction using a fibula free flap with consecutive rehabilitation by dental implants. In total, 134 implants were inserted into the transferred fibula. The functional and aesthetic results were assessed using a questionnaire. Implant loss and oral excursion were compared with diet type, speech ability, functionality, and patient satisfaction.Results
Of the 34 patients included in this study, 33 completed the questionnaire. Twenty-six patients (76%) could eat normally without the limitation of a hard or soft diet, 73% could speak intelligibly, and 31 rated the aesthetic result from good to excellent.Conclusion
The fibula flap with the early application of endosseous implants allowed primary immediate reconstruction of the jaw, significantly leading to functional and aesthetic satisfaction in patients who underwent ablative tumour surgery. 相似文献48.
49.
M. A. Gillentine L. N. Berry R. P. Goin-Kochel M. A. Ali J. Ge D. Guffey J. A. Rosenfeld V. Hannig P. Bader M. Proud M. Shinawi B. H. Graham A. Lin S. R. Lalani J. Reynolds M. Chen T. Grebe C. G. Minard P. Stankiewicz A. L. Beaudet C. P. Schaaf 《Journal of autism and developmental disorders》2017,47(3):549-562
Chromosome 15q11q13 is among the least stable regions in the genome due to its highly complex genomic architecture. Low copy repeat elements at 15q13.3 facilitate recurrent copy number variants (CNVs), with deletions established as pathogenic and CHRNA7 implicated as a candidate gene. However, the pathogenicity of duplications of CHRNA7 is unclear, as they are found in affected probands as well as in reportedly healthy parents and unaffected control individuals. We evaluated 18 children with microduplications involving CHRNA7, identified by clinical chromosome microarray analysis (CMA). Comprehensive phenotyping revealed high prevalence of developmental delay/intellectual disability, autism spectrum disorder, and attention deficit/hyperactivity disorder. As CHRNA7 duplications are the most common CNVs identified by clinical CMA, this study provides anticipatory guidance for those involved with care of affected individuals. 相似文献
50.
van der Schaaf IC Wermer MJ Velthuis BK Buskens E Bossuyt PM Rinkel GJ 《Journal of neurology, neurosurgery, and psychiatry》2006,77(6):748-752