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排序方式: 共有873条查询结果,搜索用时 15 毫秒
861.
PM Mannucci ; K Schimpf ; T Abe ; LM Aledort ; K Anderle ; DB Brettler ; MW Hilgartner ; PB Kernoff ; M Kunschak ; CW McMillan ; et al. 《Transfusion》1992,32(2):134-138
A multicenter prospective study was carried out to evaluate whether a vapor-heated factor VIII concentrate transmitted blood-borne viral infections over a surveillance period of 15 months. Thirty-five patients with hemophilia and von Willebrand disease who had never received any blood components were treated. Twenty-eight were analyzed and found not to have non-A, non-B hepatitis. Sera from 20 of these 28 patients were also tested for the antibody to the hepatitis C virus. None had sero-converted during the follow-up period. None of the patients analyzed developed markers of the hepatitis B virus (n = 17) or the human immunodeficiency virus (n = 31). This vapor-heated factor VIII concentrate carries a low risk of transmitting hepatitis and human immunodeficiency virus infection. 相似文献
862.
The carpal boss: an overview of radiographic evaluation 总被引:3,自引:0,他引:3
The carpal boss, an unmovable bony protuberance, is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This bony prominence may represent degenerative osteophyte formation and/or the presence of an os styloideum, an accessory ossification center that occurs during embryonic development. When this condition is symptomatic, patients present with complaints of pain and limitation of motion of the affected hand. The symptoms of carpal boss may result from an overlying ganglion or bursitis, an exterior tendon slipping over this bony prominence, or from osteoarthritic changes at this site. Radiographically, the view that best profiles the separate os styloideum is a lateral view utilizing 30 degrees of supination and ulnar deviation of the wrist. Once a diagnosis has been made, treatment can range from the use of nonsteroidal antiinflammatory medication and limited use of the wrist to surgical excision of the anatomic abnormality. 相似文献
863.
PM LOUGHNAN PN McDOUGALL H BALVIN LW DOYLE AL SMITH 《Journal of paediatrics and child health》1996,32(3):268-269
Abstract: The clinical details are reported of two premature infants who developed late onset haemorrhagic disease after receiving their initial doses of vitamin K1 prophylaxis intravenously. Both reported infants had received two doses of intravenous vitamin K1 , 0.1 mg, in the 1st week of life, and a further oral dose, 1.0 mg, at 4 weeks. Bleeding due to vitamin K deficiency occurred on days 74 and 84, respectively. Vitamin K deficiency bleeding is rare in low birthweight infants, probably because it has been routine practice to give such infants intramuscular vitamin K1 . One of the reported infants had cytomegalovirus hepatitis, the other did not have liver disease. These findings could be explained if intramuscular vitamin K1 were to have a longer duration of effect than intravenous vitamin K1 . This may be because intramuscular vitamin K1 acts as a depot preparation. The findings suggest that intravenous vitamin K1 is less effective than intramuscular for long-term prophylaxis against late onset haemorrhagic disease. Intravenous vitamin K1 should not be used for long-term prophylaxis in the prevention of late onset haemorrhagic disease. 相似文献
864.
Computed tomographic (CT) scans and magnetic resonance (MR) images in 103 patients with either a deep-lobe parotid tumor extending into the parapharyngeal space, a minor salivary gland tumor, a neuroma, or a paraganglioma were reviewed. The parotid or extraparotid nature of these masses was established by identifying a fat plane between the mass and the parotid gland. This was more reliably accomplished with MR imaging than with CT. Although dynamic CT allowed identification of the glomus tumors, MR imaging also permitted diagnosis of these lesions. The inherent CT and MR imaging characteristics of most of the neuromas and minor salivary gland tumors were indistinguishable. However, the neuromas tended to displace the internal carotid artery anteriorly, whereas the salivary lesions displaced this vessel posteriorly. This artery was better identified on MR images than on CT scans. Thus, these lesions, which are the four most common primary parapharyngeal space tumors, can be distinguished on MR images by evaluating not only their inherent signal characteristics but also the surrounding fat planes and any displacement of the internal carotid artery. 相似文献
865.
Fabry disease is a genetic disorder caused by the deficiency of α-galactosidase A, resulting in the lysosomal accumulation of glycosphingolipids. Fabry disease may result in cardiac, cerebral and renal complications. Cardiac abnormalities in patients with Fabry disease were first described in the 1960s. In the 1990s a form of Fabry disease confined to the heart was reported; however, this variant is extremely rare and a more appropriate concept is of cardiac predominance of the disease in some patients. Up to 60% of males with classic Fabry disease have cardiac abnormalities, including left ventricular hypertrophy, valvular dysfunction and conduction abnormalities. Recent data suggest that left ventricular mass and systolic function in patients with Fabry disease improve after 12 months of enzyme replacement therapy (ERT); however, many of the patients studied are relatively young and have mild cardiac abnormalities, suggesting that more research into the efficacy of ERT in older patients is necessary.
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
866.
Hemoglobin switching during murine embryonic development: evidence for two populations of embryonic erythropoietic progenitor cells 总被引:8,自引:4,他引:8
Explants of normal mouse embryonic tissues and disaggregated embryonic single cells were cultured in vitro to study the erythropoietic progenitor cells present during embryonic development. The results indicate that there are two populations of erythropoietic progenitor cells committed to different hemoglobin synthetic programs. These progenitor cells are present at an early gestational stage prior to the formation of the fetal hepatic primordium. One population of progenitors can be stimulated by erythropoietin alone to form usually small erythroid colonies after culture for six days in vitro. These erythroblasts primarily synthesize embryonic hemoglobins, but produce some adult hemoglobins as well. The other population of progenitors requires stimulation by both erythropoietin and adult spleen cell- conditioned medium, and usually forms large erythroid colonies after culture for six days in vitro. These erythroblasts produce only adult hemoglobins. 相似文献
867.
868.
Erik F Hensen Jeroen C Jansen Maaike D Siemers Jan C Oosterwijk Annette HJT Vriends Eleonora PM Corssmit Jean-Pierre Bayley Andel GL van der Mey Cees J Cornelisse Peter Devilee 《European journal of human genetics : EJHG》2010,18(1):62-66
Germline mutations in SDHD predispose to the development of head and neck paragangliomas, and phaeochromocytomas. The risk of developing a tumor depends on the sex of the parent who transmits the mutation: paragangliomas only arise upon paternal transmission. In this study, both the risk of paraganglioma and phaeochromocytoma formation, and the risk of developing associated symptoms were investigated in 243 family members with the SDHD.D92Y founder mutation. By using the Kaplan–Meier method, age-specific penetrance was calculated separately for paraganglioma formation as defined by magnetic resonance imaging (MRI) and for paraganglioma-related signs and symptoms. Evaluating clinical signs and symptoms alone, the penetrance reached a maximum of 57% by the age of 47 years. When MRI detection of occult paragangliomas was included, penetrance was estimated to be 54% by the age of 40 years, 68% by the age of 60 years and 87% by the age of 70 years. Multiple tumors were found in 65% and phaeochromocytomas were diagnosed in 8% of paraganglioma patients. Malignant paraganglioma was diagnosed in one patient (3%). Although the majority of carriers of a paternally inherited SDHD mutation will eventually develop head and neck paragangliomas, we find a lower penetrance than previous estimates from studies based on predominantly index cases. The family-based study described here emphasizes the importance of the identification and inclusion of clinically unaffected mutation carriers in all estimates of penetrance. This finding will allow a more accurate genetic counseling and warrants a ‘wait and scan'' policy for asymptomatic paragangliomas, combined with biochemical screening for catecholamine excess in SDHD-linked patients. 相似文献
869.
Caroline Jaarsma Simon Schalla Emile C Cheriex Martijn W Smulders Ivo van Dongen Patricia J Nelemans Anton PM Gorgels Joachim E Wildberger Harry JGM Crijns Sebastiaan CAM Bekkers 《Journal of cardiovascular magnetic resonance》2013,15(1):5
Background
Although echocardiography is used as a first line imaging modality, its accuracy to detect acute and chronic myocardial infarction (MI) in relation to infarct characteristics as assessed with late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) is not well described.Methods
One-hundred-forty-one echocardiograms performed in 88 first acute ST-elevation MI (STEMI) patients, 2 (IQR1-4) days (n = 61) and 102 (IQR92-112) days post-MI (n = 80), were pooled with echocardiograms of 36 healthy controls. 61 acute and 80 chronic echocardiograms were available for analysis (53 patients had both acute and chronic echocardiograms). Two experienced echocardiographers, blinded to clinical and CMR data, randomly evaluated all 177 echocardiograms for segmental wall motion abnormalities (SWMA). This was compared with LGE-CMR determined infarct characteristics, performed 104 ± 11 days post-MI. Enhancement on LGE-CMR matched the infarct-related artery territory in all patients (LAD 31%, LCx 12% and RCA 57%).Results
The sensitivity of echocardiography to detect acute MI was 78.7% and 61.3% for chronic MI; specificity was 80.6%. Undetected MI were smaller, less transmural, and less extensive (6% [IQR3-12] vs. 15% [IQR9-24], 50 ± 14% vs. 61 ± 15%, 7 ± 3 vs. 9 ± 3 segments, p < 0.001 for all) and associated with higher left ventricular ejection fraction (LVEF) and non-anterior location as compared to detected MI (58 ± 5% vs. 46 ± 7%, p < 0.001 and 82% vs. 63%, p = 0.03). After multivariate analysis, LVEF and infarct size were the strongest independent predictors of detecting chronic MI (OR 0.78 [95%CI 0.68-0.88], p < 0.001 and OR 1.22 [95%CI0.99-1.51], p = 0.06, respectively). Increasing infarct transmurality was associated with increasing SWMA (p < 0.001).Conclusions
In patients presenting with STEMI, and thus a high likelihood of SWMA, the sensitivity of echocardiography to detect SWMA was higher in the acute than the chronic phase. Undetected MI were smaller, less extensive and less transmural, and associated with non-anterior localization and higher LVEF. Further work is needed to assess the diagnostic accuracy in patients with non-STEMI. 相似文献870.
Abstract: Gingivitis is caused by several known systemic and local factors. Among systemic factors, the role of hormonal changes during pregnancy is well established. While presence of fixed orthodontic appliances alone may not cause gingivitis, factors such as pregnancy and poor oral hygiene combined together could precipitate acute gingival inflammation that may progress to a periodontal condition in a patient receiving orthodontic therapy. There has been an increase in the number of adult patients who are receiving orthodontic treatment. Orthodontic appliances could act as a potential plaque retentive source and aggravate inflammatory reactions that are seen during pregnancy. There is a lack of awareness regarding oral healthcare issues among patients who are pregnant and choose to seek orthodontic treatment. In addition, there is a need in the literature to outline management guidelines for patients who want to receive orthodontic treatment during pregnancy, with or without pre-existing gingival conditions. This review focuses on the aetiology of pregnancy gingivitis and the management of orthodontic patients during pregnancy. Our emphasis is on patient education, oral hygiene maintenance, preventive and treatment strategies for the management of gingival health in orthodontic patients during pregnancy. We also highlight some of the possible complications of initiating orthodontic treatment during pregnancy. 相似文献