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51.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
52.
Glomerular size has been the subject of many studies and, in a number of settings, has a direct association with the development of glomerular sclerosis. However, the normal distribution of glomerular size has not been thoroughly evaluated in the general population in the United States. To address this issue, we analyzed the baseline biopsy specimens of 103 human donor kidneys to determine the maximal planar area (MPA) of the glomerular tuft in a heterogeneous human population. The MPA of each glomerulus was determined by measurement of sections through the vascular pole and/or origin of the proximal tubule, and was determined on each section by two methods: point counting and computer planimetry. There was very high agreement between these two methods. Multivariate analysis was used to identify significant correlates with MPA. Overall, younger donors had smaller glomeruli (P < 0.0001). Black donors had a larger MPA (23.4+/-8.6 mm2 x 10(-3)) than white donors (17.9+/-6.7 mm2 x 10(-3); P < 0.001), independent of donor age. MPA was not significantly different between genders. This heterogeneity in glomerular size may confound clinical studies if not recognized and may help explain differences in glomerular structure and function in response to injurious processes. 相似文献
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LC Edozien MRCOG FN Mayers FRCOG MR Gowland FRCR 《International journal of clinical practice》1997,51(5):305-307
Both the incidence of twin pregnancy and the demand for prenatal diagnosis are increasing. Unfortunately, biochemical screening and ultrasound scanning are less reliable for prenatal diagnosis in twin pregnancies than in singletons. Amniocentesis and chorionic villous biopsy are usually diagnostic in singleton pregnancies but may be marred by sampling errors in twin gestations. Where a congenital anomaly has been diagnosed in a twin pregnancy, difficult decisions may have to be made, especially if one twin is unaffected. In these cases, special skills are required to ensure that adequate information, psychological support and optimal medical care are provided. 相似文献
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Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery.Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field. 相似文献
58.
Luiz?Claudio?Santos?Thuler Maria?S.?Pombo-de-OliveiraEmail author 《Annals of hematology》2017,96(3):355-362
The WHO classification that defines subtypes of acute myeloid leukaemias (AMLs) is relatively unexplored at the population-based level. This study aimed to examine the frequency of acute promyelocytic leukaemia (APL or AML-M3) in Brazil. Data were extracted from 239 cancer centres (2001–2012) and categorized according to the International Classification of Diseases for Oncology (CID-O 3.0) and WHO classification (n?=?9116). CID-O3 code 9866 identified 614 APL patients. AML not otherwise specified (NOS) was frequent, and the APL group represented the main subtype specified. The mean age of APL was lower than that of other AMLs (31.5, standard deviation (SD) 18.6 versus 40.9, SD 24.6; p?<?0.001); there was a high frequency of APL in the 13–21-year-old (11.8 %) and ≤12.9-year-old (6.4 %) age groups. Time taken to begin treatment (as ≤14 days versus >14 days) and induction death rate were lower in APL than in other AML subtypes (p?<?0.001). This report provides additional evidence on the distribution of APL among cases of AML in Brazil. 相似文献
59.
Marina Papais Alvarenga Luiz Claudio Santos Thuler Silvio Peçanha Neto Claudia Cristina Ferreira Vasconcelos Solange Gomes Camargo Marcos Papais Alvarenga Regina Maria Papais-Alvarenga 《Journal of neurology》2010,257(6):992-998
The aim of this study was to describe the demographic, clinical and laboratory features of idiopathic acute transverse myelitis
(IATM). Patients with non-compressive ATM receiving care at Hospital da Lagoa, Rio de Janeiro (Brazil) between 2000 and 2008
were selected. Of the 70 cases of acute myelopathies, the idiopathic form was identified in 41 following exclusion of the
cases associated with systemic lupus erythematosus (n = 1), Sjogren’s syndrome (n = 1), herpes zoster (n = 1), cytomegalovirus in an HIV-positive patient (n = 1), Schistosoma mansoni (n = 1), actinic myelitis (n = 1), infectious myelitis of unknown etiology (n = 2) and those that, following the first attack of myelitis, converted to NMO (n = 19) or to clinically defined MS (n = 2). Of the 41 cases of IATM, the majority of patients were female (68.3%) and white (65.9%). Median age at first myelitis
was 37.0 ± 11.8 years. Over a median observation time of 36 months, 39.0% of patients remained monophasic, while recurrences
occurred in 61.0% of cases. The number of ATM/patient ranged from one to seven. Among the recurrent cases the median time
between the first and the second ATM was 12 months (range 1–150 months).The first myelitis was characterized mainly by partial
myelitis with motor and sensorial dysfunction (63.4%). Complete and severe myelitis occurred more frequently among monophasic
patients and partial myelitis with moderate dysfunction at onset in recurrent cases; however, over the long-term, dysfunction
and disability were mild in both groups. Serial spine MRI confirmed spinal cord inflammation in 92.0% of cases and extensive
spinal cord lesion was identified in 61.0%. Brain MRI was normal or not suggestive of MS in 94.4% of cases. CSF showed pleocytosis
in 41.2%, increased IgG index in 24.0% and oligoclonal bands in 38.0% of 34 patients tested. Abnormal visual evoked potentials
occurred in 11.5% of 26 patients. Positivity for anti-AQP4 was found in 23.5% of the 17 cases tested, suggesting limited forms
of NMO. This study suggests some new aspects of the clinical course of IATM such as the high conversion rate to NMO, the predominance
of women and a higher frequency of recurrent forms. 相似文献
60.