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排序方式: 共有732条查询结果,搜索用时 15 毫秒
81.
82.
MRMdaSA Rafael† CMBM Fernandes† JMdaC Machado‡ PAPA Rodrigues‡ OJP Cardoso‡ A Afonso§ AB Sousa¶ FMDdeA Pacheco† RM Proença ‡ 《Journal of the European Academy of Dermatology and Venereology》2003,17(4):449-451
We report a case of atypical bullous pyoderma gangrenosum associated with acute myeloid leukaemia in which we found atypical myeloid cells within the skin lesion. Although there have been many reported cases of leukaemia-associated pyoderma gangrenosum, the finding of myeloblasts in the skin has rarely been described. 相似文献
83.
Warren R. Stanton PhD Jane L. Kelly AB Deborah A. Bunyan MSc Phil A. Silva PhD 《The Australian & New Zealand journal of obstetrics & gynaecology》1992,32(4):338-340
Fertility is dependent on sexual maturity, which is associated with a number of factors, including body mass. In this study the Body Mass Index (BMI) was used to estimate body fat in a large sample of 13-year-old New Zealand girls. Nearly half of the subjects (46%) had experienced the menarche. Expected gain in body mass was calculated from growth rates at earlier ages and used to examine whether deviation from the expected gain was associated with the onset of the menarche. In general, the results show an association between the menarche and gain in body mass. However, many girls who failed to achieve their expected gain had experienced the menarche (18%), indicating that the relationship between body weight and the menarche may not be causal or is mediated by other factors. 相似文献
84.
85.
NUR AIN ALIAS WAN AZANI MUSTAFA MOHD AMINUDIN JAMLOS AHMED ALKHAYYAT KHAIRUL SHAKIR AB RAHMAN RAMI Q. MALIK 《Oncology research》2021,29(5):365-376
Cervical cancer is a prevalent and deadly cancer that affects women all over the world. It affects about 0.5 million women anually and results in over 0.3 million fatalities. Diagnosis of this cancer was previously done manually, which could result in false positives or negatives. The researchers are still contemplating how to detect cervical cancer automatically and how to evaluate Pap smear images. Hence, this paper has reviewed several detection methods from the previous researches that has been done before. This paper reviews pre-processing, detection method framework for nucleus detection, and analysis performance of the method selected. There are four methods based on a reviewed technique from previous studies that have been running through the experimental procedure using Matlab, and the dataset used is established Herlev Dataset. The results show that the highest performance assessment metric values obtain from Method 1: Thresholding and Trace region boundaries in a binary image with the values of precision 1.0, sensitivity 98.77%, specificity 98.76%, accuracy 98.77% and PSNR 25.74% for a single type of cell. Meanwhile, the average values of precision were 0.99, sensitivity 90.71%, specificity 96.55%, accuracy 92.91% and PSNR 16.22%. The experimental results are then compared to the existing methods from previous studies. They show that the improvement method is able to detect the nucleus of the cell with higher performance assessment values. On the other hand, the majority of current approaches can be used with either a single or a large number of cervical cancer smear images. This study might persuade other researchers to recognize the value of some of the existing detection techniques and offer a strong approach for developing and implementing new solutions. 相似文献
86.
The clinical spectrum of postpartum thyroid disease 总被引:1,自引:0,他引:1
Lazarus JH; Hall R; Othman S; Parkes AB; Richards CJ; McCulloch B; Harris B 《QJM : monthly journal of the Association of Physicians》1996,89(6):429-435
The clinical and biochemical features of postpartum thyroid disease were
analysed in 152 antithyroid peroxidase antibody-positive (anti TPO+ve)
women and compared with 239 anti-TPO-ve age-matched control postpartum
women. All were assessed monthly for up to 12 months postpartum. Seventy
three anti-TPO+ve women developed post-partum thyroiditis (PPT): 19.2%
hyperthyroid alone, 49.3% hypothyroid alone, and 31.5% characterized by
hyper- followed by hypothyroidism. None of the antibody-negative women
developed any thyroid dysfunction. A significant increase in many of eleven
symptoms of hypothyroidism and some of eight symptoms of hyperthyroidism
compared to control women was observed in all anti-TPO+ve women,
independent of thyroid status. This was particularly seen in women who
later developed PPT when they were euthyroid, but was also observed in
euthyroid anti-TPO+ve women who showed no decline of thyroid function
during the postpartum period. Although PPT is usually transient, this
condition, and the euthyroid antibody-positive state, may be associated
with significant symptomatology, including an increased incidence of minor
to moderate depression. Early recognition of this syndrome by antenatal
screening of thyroid antibodies may contribute to improved management of
women during the postpartum period.
相似文献
87.
88.
J L Fleg G Gerstenblith A B Zonderman L C Becker M L Weisfeldt P T Costa E G Lakatta 《Circulation》1990,81(2):428-436
Although a silent ischemic electrocardiographic response to treadmill exercise in clinically healthy populations is associated with an increased likelihood of future coronary events (i.e., angina pectoris, myocardial infarction, or cardiac death), such a response has a low predictive value for future events because of the low prevalence of disease in asymptomatic populations. To examine whether detection of reduced regional perfusion by thallium scintigraphy improved the predictive value of exercise-induced ST segment depression, we performed maximal treadmill exercise electrocardiography (ECG) and thallium scintigraphy (201Tl) in 407 asymptomatic volunteers 40-96 years of age (mean = 60) from the Baltimore Longitudinal Study on Aging. The prevalence of exercise-induced silent ischemia, defined by concordant ST segment depression and a thallium perfusion defect, increased more than sevenfold from 2% in the fifth and sixth decades to 15% in the ninth decade. Over a mean follow-up period of 4.6 years, cardiac events developed in 9.8% of subjects and consisted of 20 cases of new angina pectoris, 13 myocardial infarctions, and seven deaths. Events occurred in 7% of individuals with both negative 201Tl and ECG, 8% of those with either test positive, and 48% of those in whom both tests were positive (p less than 0.001). By proportional hazards analysis, age, hypertension, exercise duration, and a concordant positive ECG and 201Tl result were independent predictors of coronary events. Furthermore, those with positive ECG and 201Tl had a 3.6-fold relative risk for subsequent coronary events, independent of conventional risk factors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
89.
Peroxidase-H2O2-halide system: Cytotoxic effect on mammalian tumor cells 总被引:28,自引:0,他引:28
Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo. 相似文献
90.
Tumor necrosis factor alpha-induced endothelial tissue factor is located on the cell surface rather than in the subendothelial matrix 总被引:3,自引:0,他引:3
Mulder AB; Hegge-Paping KS; Magielse CP; Blom NR; Smit JW; van der Meer J; Hallie MR; Bom VJ 《Blood》1994,84(5):1559-1566
Because there is no consensus regarding the precise distribution of induced endothelial tissue factor (TF), we studied TF activity in and on tumor necrosis factor alpha-stimulated cultured human umbilical vein endothelial cells (ECs) and their underlying matrix. TF was mainly expressed on the cell surface. Only small traces were found on the apical surface suggesting that TF is predominantly located on the basolateral side of the cell membrane. The presence of TF on the cell surface was confirmed by flow cytometry. Subendothelial TF activity appeared to be dependent upon the procedure used to remove the stimulated EC monolayer. Whereas ammonium hydroxide or hypotonic lysis resulted in relatively high levels of matrix-associated TF, virtually no TF was found on the matrix after mild enzymatic detachment of stimulated ECs. Cell removal with EDTA resulted in intermediate levels of matrix-associated TF. Neither the enzymatic treatment nor EDTA degraded or removed this TF activity. Similar patterns were observed for matrix-associated TF antigen and EC surface markers. Electron microscopic analysis showed cell fragments on the matrix after monolayer lysis. The findings strongly suggest that induced endothelial TF associated with the subendothelial matrix actually represents TF on EC remnants. 相似文献