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排序方式: 共有309条查询结果,搜索用时 15 毫秒
1.
TF Leung WC Tsoi CK Li KW Chik MMK Shing PMP Yuen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(6):705-777
We describe a 15-y-old girl with Fechtner-like syndrome, who is the first Chinese reported to have this rare syndrome. She presented with left homonymous hemianopia and neuroimaging revealed haemorrhage in both parietal and occipital lobes. Peripheral blood smear showed macrothrombocytopenia and intracytoplasmic inclusion bodies inside leucocytes. Thrombocytopenia and proteinuria responded to intravenous immunoglobulin and pulsed methylprednisolone. This case illustrates that life-threatening haemorrhage can occur in patients with Fechtner syndrome. Although there was no effective treatment reported in the literature, high dose steroid and immunoglobulin seemed to be useful in our patient. Our patient also had nephritic-nephrotic syndrome with renal insufficiency, which is unusual in adolescent female patients. 相似文献
2.
Occupational exposure to HIV is becoming a daily hazard in many emergency departments. Emergency physicians who are protected by disability insurance policies are likely to believe that if they are unable to continue working because of HIV-positive status, their disability policies will provide them with a source of income. Unfortunately, analysis of case law regarding claims under disability policies shows that the law is unlikely to consider an asymptomatic, HIV-positive physician disabled for purposes of payments under disability policies. Therefore, it is necessary for emergency physicians to make sure this issue is resolved before buying and relying on a disability policy so that an anticipated safety net will be operative over the full range of hazards that emergency physicians face.[Lavely R: The HIV-positive physician and disability insurance. Ann Emerg Med June 1994;23:1355-1362.] 相似文献
3.
Attenuation correction in myocardial perfusion SPECT/CT: effects of misregistration and value of reregistration. 总被引:2,自引:0,他引:2
Sibyll Goetze Tracy L Brown William C Lavely Zhe Zhang Frank M Bengel 《Journal of nuclear medicine》2007,48(7):1090-1095
The accuracy of myocardial perfusion SPECT improves with attenuation correction. Algorithms for attenuation correction in hybrid SPECT/CT systems have the potential for misregistration of emission and transmission scans because CT and SPECT are obtained sequentially. Misregistration will influence regional tracer distribution and may reduce diagnostic accuracy. This study focused on the role of misregistration in cardiac SPECT/CT and the performance of a software-based approach for reregistration. METHODS: We included 105 consecutive patients who underwent clinical myocardial perfusion imaging on a SPECT/CT system. Images were quantitatively assessed for misregistration using fusion software. Results were recorded in millimeters in the x-, y-, and z-axes. Regional tracer uptake in 6 segments (anterior, septal, inferior, lateral, anteroapical, and inferoapical) for noncorrected and attenuation-corrected images before and after reregistration was obtained from polar maps. To determine the relative influence of misregistration, we correlated individual differences between noncorrected and attenuation-corrected images, as well as between attenuation-corrected images before and after reregistration, with the degree of misregistration in a multivariate analysis including additional clinical variables such as sex and body weight. RESULTS: The difference in regional radiotracer uptake was significant between noncorrected and attenuation-corrected images in all 6 segments and was most pronounced in the inferior wall. On multivariate analysis, misregistration contributed significantly to changes in radiotracer distribution in the anterior (P = 0.038), septal (P = 0.011), and inferior (P = 0.006) segments. The mean misregistration was 8.6 +/- 3.8 mm (1.25 +/- 0.55 pixel). Misregistration of one or more pixels was observed in 64% of studies. Reregistration of misalignment significantly affected regional radiotracer distribution in the segments shown to be influenced by misregistration. CONCLUSION: Misregistration occurs with SPECT/CT systems and influences regional tracer distribution on attenuation-corrected myocardial images. Reregistration of misaligned studies may be a useful tool for correction. The impact of this strategy on the diagnostic and prognostic accuracy of cardiac hybrid imaging needs to be determined. 相似文献
4.
5.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
6.
PTEN抑癌基因在乳腺癌组织中的表达及其与乳腺癌微小转移灶的关系 总被引:1,自引:0,他引:1
目的:研究PTEN抑癌基因在乳腺癌组织中的表达,探讨其与乳腺癌病人的外周血、骨髓及前哨淋巴结微小转移灶之间的关系。方法:选择53例乳腺癌病人的组织标本,用免疫组织化学方法检测原发肿瘤PTEN蛋白的表达;用定量RT鄄PCR法测定原发肿瘤PTENmRNA的表达。以免疫细胞化学法检测外周血和骨髓中的微小转移灶;HE染色和免疫组织化学法检测前哨淋巴结中的微小转移灶。结果:外周血、骨髓及前哨淋巴结中微小转移灶的检出率分别是24.5%,56.6%,26.4%和41.5%。乳腺癌组织中PTEN蛋白表达呈丢失者占35.8%,后者与外周血和骨髓微小转移灶间无显著关系,而与前哨淋巴结中的微小转移密切相关(P≤0.001)。PTENmRNA的表达与外周血、骨髓及前哨淋巴结中的微小转移灶之间均无显著相关性。结论:乳腺癌组织中PTEN蛋白表达的丢失与前哨淋巴结中的微小转移有密切关系,可作为预测其早期转移的重要指标。 相似文献
7.
经肛门内镜显微手术切除直肠肿瘤 总被引:14,自引:3,他引:14
目的评价经肛门内镜显微手术(TEM)切除直肠绒毛状腺瘤和早期直肠癌的应用效果。方法分析我院总结1995年11月至2001年12月27例TEM手术的临床资料。结果本组患者肿瘤直径中位值2.5cm,肿瘤下缘与齿状线距离(8.9±3.4)cm,肿瘤侵犯直肠周径范围(35.7±17.5)%。平均手术时间(109±46)min。平均住院日4.5d。无围手术期死亡。手术并发症有尿潴留、暂时性大便失禁和慢性阻塞性肺病(COPD)复发。术中2例切穿至腹腔,即刻内镜下修补成功。切缘100%瘤细胞阴性。病理示直肠绒毛状腺瘤14例、直肠腺癌13例,后者包括pTis2例,pT16例和pT25例。直肠癌腔内超声肿瘤T分期符合率为84.6%。5例pT2中2例中转前切除术,1例接受术后放疗,2例无附加任何治疗。平均随访18个月,所有病例无局部复发。死亡2例,但无复发迹象。结论TEM易行且安全,是直肠绒毛状腺瘤和部分T1直肠癌的治愈性手术,也可作为T2直肠癌的姑息性治疗手段。 相似文献
8.
G6PD San Francisco: a new variant of glucose-6-phosphate dehydrogenase associated with congenital nonspherocytic hemolytic anemia 总被引:2,自引:0,他引:2
Congenital nonspherocytic hemolytic anemia in an adult male of Scandinavian ancestry was associated with virtual absence of G6PD activity in red cells. Characterization of G6PD purified from leukocytes using standard WHO techniques revealed diminished electrophoretic mobility, marked lability on heating at 46 degrees C, normal pH optimum and utilization of alternate substrates (2-deoxy G6P, D-amino NADP), elevated Km NADP, and striking susceptibility to NADPH inhibition. The variant G6PD, which appears to be unique, has been designated G6PD San Francisco. An unusual feature of the variant enzyme, susceptibility to inactivation by brief periods of dialysis, could be prevented by addition of 200 microM NADP to the dialysis solution. In red cells, where G6PD activity was essentially absent, regeneration of reduced glutathione was totally curtailed in vitro, while in leukocytes, where residual G6PD activity was approximately 60% of normal, hexose monophosphate shunt activity, oxygen consumption during phagocytosis, and bacterial killing were unimpaired. Thus, instability of the variant enzyme rather than its unfavorable kinetics appeared to be an important determinant of abnormal cell function. 相似文献
9.
Moderation of hemophilia A phenotype by the factor V R506Q mutation 总被引:11,自引:1,他引:11
Nichols WC; Amano K; Cacheris PM; Figueiredo MS; Michaelides K; Schwaab R; Hoyer L; Kaufman RJ; Ginsburg D 《Blood》1996,88(4):1183-1187
Although many examples of unrelated hemophilia A patients carrying identical point mutations in the factor VIII (FVIII) gene have been reported, the clinical phenotype is not always the same among patients sharing the same molecular defect. Possible explanations for this discrepancy include undetected additional mutations in the FVIII gene or coinheritance of mutations at other genetic loci that modulate FVIII function. We report molecular genetic analysis of potential modifying genes in two sets of unrelated patients carrying common FVIII missense mutations but exhibiting different levels of clinical severity. Both mutations (FVIII R1689C and R2209Q) are associated with severe hemophilia A in some patients and mild/moderate disease in others. The common von Willebrand disease type 2N mutation (R91Q) was excluded as a modifying factor in these groups of patients. However, analysis of the recently described factor V (FV) R506Q mutation (leading to activated protein C resistance) identified a correlation of inheritance of this defect with reduced hemophilia A severity. Two moderately affected hemophilia A patients, each with either of two FVIII gene mutations, were heterozygous for FV R506Q, whereas two severely affected patients and two moderately affected patients were homozygous normal at the FV locus. Our results suggest that coinheritance of the FV R506Q mutation may be an important determinant of clinical phenotype in hemophilia A and that modification of the protein C pathway may offer a new strategy for the treatment of FVIII deficiency. 相似文献
10.
Zhijie Dai Sookja K Chung Dengshun Miao Kam S Lau Alfred WH Chan Annie WC Kung 《Journal of bone and mineral research》2011,26(3):582-590
myo‐Inositol (MI) plays an essential role in several important processes of cell physiology, is involved in the neural system, and provides an effective treatment for some psychiatric disorders. Its role in osteogenesis and bone formation nonetheless is unclear. Sodium/MI cotransporter 1 (SMIT1, the major cotransporter of MI) knockout (SMIT1?/?) mice with markedly reduced tissue MI levels were used to characterize the essential roles of MI and SMIT1 in osteogenesis. SMIT1?/? embryos had a dramatic delay in prenatal mineralization and died soon after birth owing to respiratory failure, but this could be rescued by maternal MI supplementation. The rescued SMIT1?/? mice had shorter limbs, decreased bone density, and abnormal bone architecture in adulthood. Deletion of SMIT1 resulted in retarded postnatal osteoblastic differentiation and bone formation in vivo and in vitro. Continuous MI supplementation partially restored the abnormal bone phenotypes in adult SMIT1?/? mice and strengthened bone structure in SMIT1+/+ mice. Although MI content was much lower in SMIT1?/? mesenchymal cells (MSCs), the I(1,4,5)P3 signaling pathway was excluded as the means by which SMIT1 and MI affected osteogenesis. PCR expression array revealed Fgf4, leptin, Sele, Selp, and Nos2 as novel target genes of SMIT1 and MI. SMIT1 was constitutively expressed in multipotential C3H10T1/2 and preosteoblastic MC3T3‐E1 cells and could be upregulated during bone morphogenetic protein 2 (BMP‐2)–induced osteogenesis. Collectively, this study demonstrated that deficiency in SMIT1 and MI has a detrimental impact on prenatal skeletal development and postnatal bone remodeling and confirmed their essential roles in osteogenesis, bone formation, and bone mineral density (BMD) determination. © 2011 American Society for Bone and Mineral Research. 相似文献