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51.
A methodological approach to the classification of dermoscopy images.   总被引:2,自引:0,他引:2  
In this paper a methodological approach to the classification of pigmented skin lesions in dermoscopy images is presented. First, automatic border detection is performed to separate the lesion from the background skin. Shape features are then extracted from this border. For the extraction of color and texture related features, the image is divided into various clinically significant regions using the Euclidean distance transform. This feature data is fed into an optimization framework, which ranks the features using various feature selection algorithms and determines the optimal feature subset size according to the area under the ROC curve measure obtained from support vector machine classification. The issue of class imbalance is addressed using various sampling strategies, and the classifier generalization error is estimated using Monte Carlo cross validation. Experiments on a set of 564 images yielded a specificity of 92.34% and a sensitivity of 93.33%.  相似文献   
52.
This study reports an opinion survey of 211 nonpsychiatrist physicians in two general hospitals who estimated that 16.1% of their patients have psychiatric disorders and that they spent 13.8% of their time in treating the psychiatric components of their patients' illnesses. Physicians indicated that anxiety and psychosomatic and depressive illness were the most frequent psychiatric disorders and that one-third of them would personally treat such disorders without referral to psychiatric consultation. The findings also suggest that adequate undergraduate psychiatric education was associated with increased recognition of psychiatric disorders and more preference for their personal treatment. In addition, it provides a possible explanation for the discrepancy between the high prevalence of psychiatric disorders in general hospital patients and the low referral rate to psychiatric consultation.  相似文献   
53.
A 17-year-old male presented to a local hospital with symptoms of pneumonia and a hacking cough productive of yellow sputum. Direct examination of a bronchial lavage sample revealed organisms morphologically consistent with Blastomyces dermatitidis, which was confirmed by culture. The patient was placed on intravenous antifungal therapy and his condition improved dramatically. OBJECTIVES: to describe the gross and microscopic morphologies of both yeast and mold forms of B. dermatitidis; to identify B. dermatitidis given patient history, and microscopic and colony morphology; to describe the symptoms of primary pulmonary infections caused by B. dermatitidis, and to name additional tissues typically affected by the systemic pathogen.  相似文献   
54.
Geographical variations in the incidence of disease are of considerable theoretical and practical importance. It has been claimed that the distribution of acute lymphoblastic leukemia (ALL) phenotypes in Saudi Arabia is different from that recorded in the Western literature. One hundred and twelve (112) patients under 15 years of age, diagnosed as ALL between January 1992 and May 1994 had immunophenotypes performed on their blast cells. Common ALL (cALL) together with pre-B-ALL, formed 86.5% of the total; B-cell 3%, T-cell 6% and null cell 4.5%. These figures are not significantly different from the Western literature. A previous claim from this institution in 1990, that both null and B-cell ALL were significantly increased compared with elsewhere, is not supported by the present figures. Age and sex distribution, and FAB classification, L1 77%, L2 20% and L3 3%, were also of the same order as described elsewhere and, in particular, there was no increase in the frequency of L3 subtype.  相似文献   
55.
In the present studies we have compared the levels of glutathione(GSH) and GSH-related enzymes in lung tumors and correspondingnormal tissues obtained from the same individuals. We have alsoimmunologically quantitated the relative amounts of glutathioneS-transferase (or GST-P) type antigen in tumors and adjacentnormal tissues from five patients. GST activities towards 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid were found to beelevated in tumors from two out of five patients (patients #1and 4), whereas the activity towards these substrates was markedlysuppressed in the tumor tissue from one of the patients (#5).Immunotitration and Western blot studies using antibodies raisedagainst -type GST isoenzymes of human lung and placenta indicatedinduction of GST -type isoenzyme in tumors from patients #1and 4 and suppression of this isoenzyme in tumor from patient#5. The tumors from patients #2 and 3 did not show any increasein GST activity or GST -type antigen. Except for the tumor frompatient #5, the GSH content was higher in the tumors from otherpatients. GSH reductase activity was found to be elevated intumors of all the patients examined in this study. These resultsindicate that GSH and GSH related enzymes are differentiallyaltered in lung tumors and GSH levels and GST - or GST-P-typeisoenzyme(s) are not uniformly elevated in all tumors.  相似文献   
56.
Summary The effects of recombinant human interferons , and (IFN) on the antiproliferative activity of cytarabine in K562 human myeloid leukaemia clonogenic cells were studied in an agar capillary microassay. The addition of IFN- did not affect the antiproliferative activity of cytarabine in K562 cultures treated with low concentrations of cytarabine (10–50 nM), whereas in those treated with high concentrations (100–150 nM) IFN increased the IC50 of cytarabine on day 5 from 102 nM to 214 nM, i.e., cytarabine combined with IFN was about two-fold less potent than cytarabine alone. Similarly, low concentrations of IFN and IFN did not affect the antiproliferative activity of cytarabine on K562 colonies, but high concentrations of these two interferons: 4×103 U/ml and 104 U/ml respectively, increased the IC50 of cytarabine on day 5 to 304 nM and to 316 nM respectively, i.e. cytarabine combined with IFN or IFN was about threefold less potent than cytarabine alone. The evaluation of the present negative interactions of interferons with cytarabine is warranted in fresh cells from myeloid leukaemia patients in primary culture.Abbreviation IFN interferon  相似文献   
57.
Reaction of 6-(acetoxymethyl)-2,4-dichloropyrido[3,2-d]pyrimidine (I) with some nucleophiles was investigated. When I reacted with sodium azide afforded 2,4-diazido derivative (II). Treatment of II with sodium hydroxide underwent cyclization of the 2-azido group to tetrazolo, replacement of 4-azido group by hydroxide ion, and hydrolysis of 6-acetoxy moiety to hydroxy methyl derivative (III). While, reaction of I with hydrazine hydrate resulted in the formation of 2,4-dihydrozino-6-hydroxymethyl derivative (IV).  相似文献   
58.
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages.  相似文献   
59.
60.
BACKGROUND: Infertile women positive for thyroid antibodies suffer from a poor pregnancy/delivery outcome, although conflicting data have been published. Our objective was to investigate if levothyroxine (LT4) exerts any effect on pregnancy and/or delivery rates in thyroid peroxidase antibody (TPOAb)-positive (+) women undergoing assisted reproductive technologies. METHODS: Patients undergoing treatment were screened for TPOAb, thyroid-stimulating hormone (TSH) and free thyroxine (FT4). A total of 72 (15%) out of the 484 euthyroid women selected were TPOAb (+). These 72 patients were randomly divided into two groups: group A (n = 36) underwent LT4 treatment, group B (n = 36) placebo. Group C consisted of 412 women (85%) who were TPOAb negative (-). All patients received controlled ovarian stimulation. The endpoints of treatment were pregnancy rate, miscarriage rate and delivery rate. RESULTS: No differences in pregnancy rate were observed between the three groups. Miscarriage rate was higher in TPOAb (+) in comparison to TPOAb (-) [relative risk: 2.01 (95% CI = 1.13-3.56), P = 0.028]. CONCLUSIONS: The pregnancy rate is not affected either by presence of TPOAb or treatment with LT4. However, TPOAb (+) women show a poorer delivery rate compared to TPOAb (-). LT4 treatment in TPOAb (+) does not affect the delivery rate.  相似文献   
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