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1.
OBJECTIVE: To investigate of the potential value of morphometry and discriminant analysis for the classification of benign and malignant gastric cells and lesions. STUDY DESIGN: The data set consisted of 13,300 cells from 120 cases composed of 30 cases of cancer, 26 cases of gastritis and 64 cases of ulcer according to the final histologic diagnosis. The cytologic diagnosis was divided into 5 categories (gastritis, ulcer, inflammatory dysplasia, cancer and true dysplasia). Classification was attempted at 2 levels: the cell level to classify individual cells and the case level to classify individual cases. For the cellular classification the measured cells from 50% of available cases were selected as a training set to construct a model. The cells from the remaining cases were used as a test set to validate the model. Similarly for case classification, the same 50% of cases that were used for cell classification were used as a training set and the remaining cases as a test set. Images of routinely processed gastric smears stained by the Papanicolaou technique were analyzed by a customized image analysis system. RESULTS: Application of discriminant analysis on the test set gave correct classification of 98.4% of benign cells and 67.1% of malignant cells. On case classification, 100% accuracy was achieved for benign and malignant cases, both for the training and test sets. CONCLUSION: The application of discriminant analysis described in this paper could produce significant classification results at the cellular and individual case level.  相似文献   
2.
A prospective study was undertaken to investigate the potential value of morphometry and artificial neural networks (ANN) for the discrimination of benign and malignant gastric lesions. Two thousand five hundred cells from 23 cases of cancer, 19 cases of gastritis and 58 cases of ulcer were selected as a training set, and an additional 8524 cells from an equal number of cases of cancer, gastritis and ulcer were used as a test set. Images of routine processed gastric smears stained by the Papanicolaou technique were processed by a custom image analysis system. The application of the learning vector quantization (LVQ) classifier enabled correct classification of > 97% of benign cells and > 95% of malignant cells, obtaining an overall accuracy of > 97%. This study presents the capabilities of ANN, and also indicates that ANN and image morphometry may offer useful information on the potential of malignancy in gastric cells.  相似文献   
3.
Polypteridae (Cladistia) is a family of archaic fishes, confined to African freshwaters. On account of their primitiveness in anatomical and morphological characters and mosaic relationships among lower Osteichthyans fishes, they constitute an important subject for the study of evolution in vertebrates. Very little is known about the karyological structure of these species. In this article, a cytogenetic analysis on twenty specimens of Polypterus senegalus (Cuvier, 1829) was performed using both classical and molecular techniques. Karyotype (2n = 36; FN = 72), chromosome location of telomeric sequences (TTAGGG) n , (GATA)7 repeats and ribosomal 5S and 18S rRNA genes were examined by using Ag-NOR, classical C-banding, CMA3 staining and FISH. Staining with Ag-NOR showed the presence of two GC rich NORs on the p arm of the chromosome pair no. 1. CMA3 marked all centromerical and some (no. 1 and no. 14) telomeric regions. FISH with 5S rDNA marked the subtelomeric region of the q arm of the chromosome pair no. 14. FISH with 18S rDNA marked the telomeric region of the p arm of the chromosome pair no. 1, previously marked by Ag-NOR. (GATA)7 repeats marked the subtelomeric regions of all chromosome pairs, with the exclusion of the no. 1, 3 and 14. Hybridization with telomeric probes (TTAGGG) n showed bright signals at the end of all chromosomes. After cloning, the 5SrDNA alignment revealed an organization of sequences made up of two different classes of tandem arrays (5S type I and 5S type II) of different lengths.  相似文献   
4.
In an attempt to investigate the significance of lipid peroxidation in the pathogenesis of gastritis associated with or without Helicobacter pylori infection, malonodialdehyde (MDA) levels were measured by the thiobarbiturate assay in the gastric juice of 101 patients undergoing upper GI endoscopy and correlated with histopathological findings. Elevated MDA levels were found in all patients with gastritis compared with controls. MDA levels were significantly correlated with the extent of the mucosal inflammation and with disease activity in patients with reactive gastritis. In patients with H. pylori associated gastritis MDA levels were not correlated with disease activity but rather with the degree of atrophy. In this case, MDA levels were equal or even less than in patients with reactive gastritis. MDA levels were not affected by the history of consumption of PPIs, of H(2)-blockers or of NSAIDs over the last month before the endoscopy. It is concluded that lipid peroxidation is a mechanism involved in the pathogenesis of gastritis associated or not to H. pylori infection.  相似文献   
5.
Summary Serum Gm polymorphism was studied in 69 patients with liver cirrhosis, in 64 with liver cirrhosis plus hepatoma, in 40 with hepatoma without evidence of cirrhosis, and in 256 controls. The distribution of Gm factors in liver patients differed from that in the control group, this difference apparently being due to the distribution in cirrhosis patients negative for HBsAg and anti-HBs. Furthermore, significantly more heterozygous Gm individuals were found in this group of patients than in the control group. Thus it appears that Gm heterozygous individuals are prone to develop cryptogenic cirrhosis under the influence of other, as yet undetermined factors.  相似文献   
6.
Cytogenetic data in cartilaginous fishes are currently very inconsistent, considering that the karyotype morphology of only about seventy living species is actually known. Only in the last few years different molecular approaches, first of all physical mapping on metaphase chromosomes, have been used to investigate the cytotaxonomic relationship existing inside this interesting group of vertebrates. The aim of the work was to characterize new molecular chromosomal markers both to discriminate the different chromosome pairs and to distinguish the probable sex chromosomes in the species Torpedo torpedo, since its karyotype does not seem to exhibit heterochromosomes. Evolution of the SRY gene has received considerable attention, mainly because it has been shown to be the sex-determining locus in mammals. The gene is located in the Y chromosome where it normally occurs as a single copy. Using primers taken from the conserved SRY sequences, we characterized these regions at the molecular level and localized them on metaphase chromosomes. The PCR products revealed similar patterns in specimens of both sexes of T. torpedo, but only one fragment of the male amplification product showed a high percentage of identity with human spermatogenesis related genes, SPATA 16, SPATA 18 and UTY. Fluorescent in situ hybridization with these sequences showed the presence of spots at the subtelomeric level of two chromosome pairs in the male and of one pair in the female. Finally, these sequences are particularly useful as chromosome markers to differentiate between the male and the female karyotypes in this species.  相似文献   
7.
OBJECTIVE: To investigate the potential value of morphometry and neural networks for the discrimination of benign from malignant gastric lesions. STUDY DESIGN: One thousand cells from 19 cases of cancer, 19 cases of gastritis and 56 cases of ulcer were selected as a training set, and an additional 4,000 cells from the same cases of cancer, gastritis and ulcer were used as a test set. Images of routinely processed gastric smears stained by the Papanicolaou technique were analyzed by a custom-made image analysis system. RESULTS: Application of the neural network gave correct classification in 96% of benign cells and 89% of malignant cells. CONCLUSION: The results indicate that the use of neural networks and image morphometry may offer useful information concerning the potential of malignancy in gastric cells.  相似文献   
8.
9.
A systematic search in the available scaffolds of the Strongylocentrotus purpuratus genome has revealed that this sea urchin has 11 members of the ets gene family. A phylogenetic analysis of these genes showed that almost all vertebrate ets subfamilies, with the exception of one, so far found only in mammals, are each represented by one orthologous sea urchin gene. The temporal and spatial expression of the identified ETS factors was also analyzed during embryogenesis. Five ets genes (Sp-Ets1/2, Sp-Tel, Sp-Pea, Sp-Ets4, Sp-Erf) are also maternally expressed. Three genes (Sp-Elk, Sp-Elf, Sp-Erf) are ubiquitously expressed during embryogenesis, while two others (Sp-Gabp, Sp-Pu.1) are not transcribed until late larval stages. Remarkably, five of the nine sea urchin ets genes expressed during embryogenesis are exclusively (Sp-Ets1/2, Sp-Erg, Sp-Ese) or additionally (Sp-Tel, Sp-Pea) expressed in mesenchyme cells and/or their progenitors. Functional analysis of Sp-Ets1/2 has previously demonstrated an essential role of this gene in the specification of the skeletogenic mesenchyme lineage. The dynamic, and in some cases overlapping and/or unique, developmental expression pattern of the latter five genes suggests a complex, non-redundant function for ETS factors in sea urchin mesenchyme formation and differentiation.  相似文献   
10.
Ten patients with transitional cell carcinoma (TCC) of the bladder received 3–6 mCi of HMFG1 monoclonal antibody (MAb) intravesically. The antibody was labeled with Tc-99m using the 2-Iminothiolane method. All patients underwent transurethral resection of the bladder tumor within 12–20 h following intravesical administration of99m-Tc-HMFG1. The presence of the radiolabeled MAb in the circulation was studied by measuring the radioactivity in the serum for a period up to 20 h. Three of 10 patients underwent immunoscintigraphy (SPECT) 2–3 h postadministration and cancerous areas could be easily localized. Biopsies were taken from the tumor sites as well as from normal bladder mucosa. Absolute uptake of the administered MAb expressed as percent administered dose/kg of tissue could be evaluated only in eight patients. Multiple specimen taken from various tumor sites in every patient gave a wide range of uptake values ranging from 0 to 9.29% adm. dose/kg, whereas normal tissue uptake values ranged from 0 to 1.63, respectively.  相似文献   
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