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1.
Zhonghua Wai Ke Za Zhi ; 62(1): 58-65, 2023 Dec 01.
Artículo en Zh | MEDLINE | ID: mdl-38044609

RESUMEN

Objective: To compare the patient-reported outcomes and short-term clinical outcomes between robotic-assisted and laparoscopic-assisted radical gastrectomy for locally advanced gastric cancer. Methods: This single-center prospective randomized controlled trial was conducted in the Department of Gastrointestinal Surgery,Affiliated Hospital of Qingdao University from October 2020 to August 2022. Patients with locally advanced gastric cancer who were to undergo radical gastrectomy were selected and randomly divided into two groups according to 1∶1, and received robotic surgery and laparoscopic surgery, respectively. Patient-reported outcomes and short-term clinical outcomes (including postoperative complications, surgical quality and postoperative short-term recovery) were compared between the two groups by t test, Mann-Whitney U test, repeated ANOVA, generalized estimating equation, χ2 test and Fisher's exact test. Results: A total of 237 patients were enrolled for modified intention-to-treat analysis (120 patients in the robotic group, 117 patients in the laparoscopic group). There were 180 males and 59 females, aged (63.0±10.2) years (range: 30 to 85 years). The incidence of postoperative complications was similar between the robotic group and laparoscopic group (16.7% (20/120) vs. 15.4% (18/117), χ2=0.072, P=0.788). The robotic group had higher patient-reported outcomes scores in general health status, emotional, and social domains compared to the laparoscopic group, differences in time effect, intervention effect, and interaction effect were statistically significant (general health status: χ2 value were 275.68, 3.91, 6.38, P value were <0.01, 0.048, 0.041; emotional: χ2 value were 77.79, 6.04, 6.15, P value were <0.01, 0.014, 0.046; social: χ2 value were 148.00, 7.57, 5.98, P value were <0.01, 0.006, 0.048). However, the financial burden of the robotic group was higher, the differences in time effect, intervention effect and interaction effect were statistically significant (χ2 value were 156.24, 4.08, 36.56, P value were<0.01, 0.043,<0.01). Conclusion: Compared to the laparoscopic group, the robotic group could more effectively relieve postoperative negative emotions and improve recovery of social function in patients.

2.
Zhonghua Nei Ke Za Zhi ; 56(1): 29-33, 2017 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-28056320

RESUMEN

Objective: To investigate the clinical and laboratorial characteristics of patients with myelodysplastic syndrome (MDS) and erythroid hyperplasia. Methods: MDS patients whose bone marrow was hypercellular with erythroid lineage more than 50% and blasts account for less than 20% of non-erythroid cells were enrolled in this study. The ratio of mature erythrocytes to nucleated erythrocytes was no more than 20, namely MDS patients with erythroid hyperplasia(MDS-E). The retrospective analysis comprised 102 patients with MDS-E from the First Affiliated Hospital of Suzhou University. Clinical characteristics, karyotype, and the prognostic significance of erythroid hyperplasia were evaluated. Results: A total of 48 MDS-E patients (47.1%) presented a variety of cytogenetic abnormalities. The most frequently involved chromosomes were chromosome 8 (39.5% of all abnormal karyotypes), chromosome 7 (22.9%), followed by chromosome 5 (18.8%), chromosome 1 (16.7%) and chromosome 20 (16.7%). Hemoglobin (Hb) level affected the prognosis by survival analysis. The overall survival (OS) of MDS-E patients with Hb equal or more than 70 g/L was longer than that of patients less than 70 g/L (P<0.001). Allogeneic hematopoietic stem cell transplantation (HSCT) significantly improved the OS compared with best supportive care (P<0.001) and chemotherapy (P<0.001). The extent of erythroid hyperplasia in bone marrow did not impact on prognosis (P=0.187). Conclusions: Compared with previous reports of MDS patients, MDS-E patients have higher level of erythroid hyperplasia, more common erythroid dyshematopoiesis, more frequent 8 and 1 chromosome abnormalities. The degree of erythroid hyperplasia is not correlated with prognosis. Allogeneic hematopoietic stem cell transplantation improves the prognosis.


Asunto(s)
Aberraciones Cromosómicas , Trasplante de Células Madre Hematopoyéticas , Hiperplasia/patología , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Adulto , Anciano , Médula Ósea/patología , Femenino , Humanos , Cariotipo , Cariotipificación , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/cirugía , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
3.
Genet Mol Res ; 14(4): 18198-209, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26782467

RESUMEN

The complete mitochondrial genome of the Southern catfish (Silurus meridionalis) and the Chinese catfish (S. asotus), was determined using the long and accurate polymerase chain reaction (LA-PCR) method. The mitochondrial DNA nucleotide sequences of S. meridionalis and S. asotus were compared with those of 47 other catfish species in the same order. The total length of mitochondrial DNA for S. meridionalis and S. asotus was 16,526 and 16,525 bp, respectively, and included 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region. This mitochondrial gene arrangement is identical to that observed in other Siluriformes. To determine the relative phylogenetic positions of S. meridionalis and S. asotus, and to discover phylogenetic relationships among 24 families of Siluriformes, analyses were conducted, based on mitochondrial DNA, 12S ribosomal RNA, 16S ribosomal RNA, and 13 protein-coding gene sequence data sets. Phylogenetic analyses were congruent with a basal split of the order into Clupeiformes, Characiformes, Cypriniformes, and Siluriformes, and supported a closer relationship of the Southern catfish (family Siluridae) and the Chinese catfish (family Siluridae) to Pimelodidae than to Bagridae. We concluded that these two species are part of a molecular clade that is different from that proposed in recent studies, in which Amblycipitidae appears as a sister group. Our results showed Amblycipitidae appearing as the most basal extant, and Bagridae appearing as a sister group of Cranoglanididae and Pangasiidae. The Siluriformes showed close phylogenetic relationship to the Characiformes.


Asunto(s)
Bagres/genética , Genoma Mitocondrial , Filogenia , Análisis de Secuencia de ADN , Animales , Anotación de Secuencia Molecular , ARN Ribosómico/genética , ARN Ribosómico 16S/genética
4.
Eur Rev Med Pharmacol Sci ; 27(16): 7523-7532, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37667929

RESUMEN

OBJECTIVE: Peripheral nerve block can provide effective postoperative analgesia to patients undergoing total hip arthroplasty (THA). This study aimed to compare ultrasound-guided pericapsular nerve group (PENG) block against anterior quadratus lumborum (AQL) block for pain management in primary THA. PATIENTS AND METHODS: In this prospective, double-blind, randomized controlled trial, 90 patients undergoing primary THA under general anesthesia were randomly allocated to receive ultrasound-guided PENG block + sham AQL block ("PENG group") or ultrasound-guided AQL block + sham PENG block ("AQL" group). The primary outcome was the highest pain score on a visual analogue scale while the patient was in the recovery room. Secondary outcomes included pain scores after transfer out of the recovery room, morphine consumption, quadricep strength, duration of hospitalization, pain level one year after surgery, and incidence of complications. RESULTS: Patients in the PENG group reported significantly lower maximum pain scores in the recovery room (31.3±9.1 vs. 37.3±7.4, p=0.001), as well as significantly lower pain scores at rest at 3 h after surgery and during motion at 3 and 6 h after surgery. The two groups did not differ significantly in postoperative morphine consumption, length of hospitalization, pain level at one year after surgery, or incidence of complications. Neither block significantly weakened the quadriceps. CONCLUSIONS: PENG block may provide slightly more effective postoperative analgesia than AQL block during the early recovery period after primary THA.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Humanos , Nervio Femoral , Estudios Prospectivos , Morfina/uso terapéutico , Ultrasonografía Intervencional , Dolor
5.
Eur Rev Med Pharmacol Sci ; 26(18): 6536-6549, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36196702

RESUMEN

OBJECTIVE: The aim of our study was to determine whether abnormal hyperplasia of chondrocytes occurs in glucocorticoid-induced osteonecrosis of the femoral head (GC-ONFH) using a well-established rat model. MATERIALS AND METHODS: Rats were injected with lipopolysaccharide and methylprednisolone to induce GC-ONFH, while control animals were injected with saline (12 animals per group). Establishment of the disease model was confirmed using micro-computed tomography and hematoxylin-eosin (HE) staining of femoral head tissue sections. Chondrocyte hyperplasia was detected using HE staining and semi-quantitated using toluidine blue and saffron O staining. Expression of the autophagy marker LC3B was assessed in cartilage tissues of femoral head using immunohistochemistry. RESULTS: GC-ONFH animals showed significantly greater area of abnormal chondrocyte hyperplasia in femoral head tissue sections than control animals. They also showed significantly higher expression of LC3B in articular cartilage of the femoral head. CONCLUSIONS: GC-ONFH may be associated with abnormal chondrocyte hyperplasia in articular surface cartilage, which may be related to glucocorticoid-induced overactivation of autophagy.


Asunto(s)
Necrosis de la Cabeza Femoral , Cabeza Femoral , Animales , Condrocitos , Eosina Amarillenta-(YS)/efectos adversos , Cabeza Femoral/patología , Necrosis de la Cabeza Femoral/inducido químicamente , Necrosis de la Cabeza Femoral/patología , Glucocorticoides , Hematoxilina , Hiperplasia/inducido químicamente , Lipopolisacáridos/efectos adversos , Metilprednisolona/efectos adversos , Ratas , Cloruro de Tolonio/efectos adversos , Microtomografía por Rayos X
6.
Nat Med ; 6(10): 1160-6, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11017149

RESUMEN

The breaking of immune tolerance against autologous angiogenic endothelial cells should be a useful approach for cancer therapy. Here we show that immunotherapy of tumors using fixed xenogeneic whole endothelial cells as a vaccine was effective in affording protection from tumor growth, inducing regression of established tumors and prolonging survival of tumor-bearing mice. Furthermore, autoreactive immunity targeting to microvessels in solid tumors was induced and was probably responsible for the anti-tumor activity. These observations may provide a new vaccine strategy for cancer therapy through the induction of an autoimmune response against the tumor endothelium in a cross-reaction.


Asunto(s)
Vacunas contra el Cáncer/farmacología , Endotelio/citología , Endotelio/inmunología , Inmunoterapia/métodos , Neoplasias Experimentales/terapia , Secuencia de Aminoácidos , Animales , Antígenos CD/inmunología , Autoanticuerpos/inmunología , Linfocitos T CD4-Positivos/inmunología , Bovinos , Células Cultivadas , Reacciones Cruzadas , Endotelio Vascular/citología , Endotelio Vascular/inmunología , Humanos , Integrina alfaV , Ratones , Datos de Secuencia Molecular , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/inmunología , Péptidos/inmunología , Proteínas Tirosina Quinasas Receptoras/inmunología , Receptores de Factores de Crecimiento/inmunología , Receptores de Factores de Crecimiento Endotelial Vascular
8.
Zhonghua Xue Ye Xue Za Zhi ; 37(11): 936-941, 2016 Nov 14.
Artículo en Zh | MEDLINE | ID: mdl-27995876

RESUMEN

Objective: To investigate EVI1 expression and its associated clinical and cytogenetic characteristics in 447 acute myeloid leukemia (AML) patients. Methods: EVI1 expressions were measured in 447 AML cases from Jan. 2007 to Apr. 2015 to couple with clinical, cytogenetic and mutations' characteristics to summarize the features of AMLs with high EVI1 expression. Results: 17.9% of AML were high EVI1 expression (EVI1 +), and the remainder low EVI1 expression (EVI1-). No significant differences between the two groups in terms of age, sex, hemoglobin level, white blood cell count and platelet count were observed. More M0, M5 and M6 subtypes were observed in EVI1+ group (P= 0.027, 0.004 and 0.011, respectively). Cytogenetic abnormalities of 11q15, 11q23/MLL, 3q26, -7/7q- and t (9;11) were observed more frequently in EVI1 + group (P<0.001, <0.001, <0.001, <0.001, =0.014, respectively). Normal karyotype, inv (16), t (8;21) were observed more frequent in EVI1- group (P=0.001, 0.009, 0.002, respectively). EVI1 + was more observed in high risk cytogenetics. Mutation of NPM1 was more observed in EVI1- group (P <0.001). Remission rate in EVI1 + group was significantly lower than EVI1- group (P<0.001). Leukemia-free survival was improved in EVI1 + AML patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Conclusions: High EVI1 expression was more observed in FAB subgroup M5, harbored more cytogenetic abnormalities of 11p15, 11q23/MLL, 3q26 rearrangement, -7/7q- and t (9;11). Remission rate of high EVI1 expression AML was lower, which could be improved by allo-HSCT.


Asunto(s)
Aberraciones Cromosómicas , Proteínas de Unión al ADN , Leucemia Mieloide Aguda/genética , Proteína del Locus del Complejo MDS1 y EV11/metabolismo , Proto-Oncogenes , Adolescente , Adulto , Trastornos de los Cromosomas , Citogenética , Femenino , Humanos , Leucemia Monocítica Aguda , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Mutación , Nucleofosmina , Pronóstico , ARN Mensajero , Factores de Transcripción
9.
Exp Hematol ; 18(4): 355-9, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2182334

RESUMEN

In this study it was found that three kinds of cells, fibroblasts, endothelial cells, and macrophages, exist in fibroblastic colony-forming unit (CFU-F) colonies, consistent with the findings of others. However, when low enough bone marrow stromal cell numbers were cultured per dish, pure fibroblast, endothelial, and macrophage colonies were observed. When the cell number cultured in each dish was increased, all colonies were of mixed cell type. This evidence strongly suggests that the macrophages and endothelial cells contained in CFU-F colonies come from locally stimulated growth resulting in contamination and not from a common progenitor with fibroblasts or each other. In some longer term experiments, adipocytes were seen to appear within the colonies of late-passage pure fibroblast cultures.


Asunto(s)
Separación Celular/métodos , Fibroblastos/citología , Hematopoyesis , Células Madre/citología , Animales , Células de la Médula Ósea , Factores Estimulantes de Colonias/farmacología , Técnicas Citológicas , Endotelio/citología , Técnica del Anticuerpo Fluorescente , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Sustancias de Crecimiento/farmacología , Macrófagos/citología , Ratones , Fagocitosis
10.
Exp Hematol ; 29(1): 12-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11164101

RESUMEN

Bone marrow endothelial cells are the essential component of the bone marrow microenvironment. They produce many kinds of cytokines, including stimulators and inhibitors. Many researchers have suggested that in the presence of endothelial cell layer, CD34+CD38- cells are capable of expansion. The ability of the endothelial cell layer to protect hematopoietic stem cells from extensive differentiation may be related to the inhibitors derived from endothelial cells. The aim of the present study was to determine whether the inhibitors thymosin beta4 and AcSDKP are elaborated by murine bone marrow endothelial cells. Murine bone marrow endothelial cells (mBMECs) were cultured in serum-free conditioned medium. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the differential expression of the thymosin-beta gene, and reverse phase high-performance chromatography (HPLC) and mass spectroscopy were used to determine the concentration of thymosin beta4 (Tbeta4) and AcSDKP in EC lysate and in the medium (mBMEC-CM). Colony-forming unit granulocyte-macrophage (CFU-GM) colony assays were used to examine the effect of components (mw 3-10 kD, <3 kD) of mBMEC-CM, thymosin beta4, and AcSDKP on the proliferation of hematopoietic cells.mBMECs expressed Tbeta4 mRNA. In EC lysate and mBMEC-CM, Tbeta4 and AcSDKP were detected. After adding protease inhibitors, the concentration of Tbeta4 in EC lysate increased significantly, while the concentration of AcSDKP decreased. mBMEC-CM (mw 3-10 kD) had no effect on the formation of CFU-GM. However, mBMEC-CM (mw <3 kD) could inhibit the growth of CFU-GM. Tbeta4 (10(-11) approximately 10(-7)mol/L) and AcSDKP (10(-11) approximately 10(-5)mol/L) had dose-dependent inhibitory effects on the growth of CFU-GM. Angiotensin converting enzyme (ACE), the enzyme degrading AcSDKP, could partially eliminate the inhibitory effect of mBMEC-CM (mw <3 kD) on CFU-GM.BMECs express and secrete Tbeta4 and AcSDKP. Tbeta4 exists in the 3-10 kD component of mBMEC-CM, while AcSDKP exists in the <3 kD component of ECCM. Both components exert inhibitory effects on the proliferation of hematopoietic progenitors.


Asunto(s)
Células de la Médula Ósea/metabolismo , Hematopoyesis/fisiología , Oligopéptidos/metabolismo , Timosina/metabolismo , Animales , Células Cultivadas , Cromatografía Líquida de Alta Presión , Ensayo de Unidades Formadoras de Colonias , Medios de Cultivo Condicionados/farmacología , Medio de Cultivo Libre de Suero , Endotelio/citología , Endotelio/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Peptidil-Dipeptidasa A/farmacología , Inhibidores de Proteasas/farmacología , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Exp Hematol ; 18(4): 341-7, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2323369

RESUMEN

The effects of several growth factors on the proliferation of fibroblastic colony-forming units (CFU-F) were studied. In the present study CFU-F colonies were found to consist of fibroblasts, macrophages, and endothelial cells. Growth factors, including interleukin 3 (IL-3), interleukin 1 alpha (IL-1 alpha), epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), macrophage colony-stimulating factor (M-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and buffalo rat liver cell-conditioned medium (BRL-CM) were tested for stimulation of the proliferation of CFU-F in a standard culture in both 2% and 15% serum. Overall, the colony numbers produced in 15% serum were much higher than in 2% serum with or without growth factors. However, the influence of several growth factors on CFU-F cultured in 2% serum was relatively greater than in 15% serum when compared to controls. The stimulation of CFU-F by FGF only occurred in culture with 15% serum, and the stimulation by PDGF only occurred with 2% serum. Overall, the strongest stimulations were produced by PDGF, IL-3, and BRL-CM. Combining the other growth factors with IL-3, PDGF, or IL-1 alpha enhanced their effects only modestly. The stimulation by growth factors included increases of the cell numbers between and within colonies as well as an increase in the number of colonies. The study produced results that suggest a complex interaction mediated by growth factors between fibroblasts and other stromal cells within the CFU-F colonies and within the bone marrow itself.


Asunto(s)
Células de la Médula Ósea , Sustancias de Crecimiento/farmacología , Hematopoyesis , Células Madre/citología , Animales , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Medios de Cultivo , Fibroblastos/citología , Masculino
12.
Exp Hematol ; 18(4): 348-54, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2323370

RESUMEN

Purified normal murine bone marrow-derived fibroblasts were shown to produce a factor that stimulates the in vitro growth of fibroblastic colony-forming unit (CFU-F) colonies. Conditioned medium from the purified fibroblasts (F-CM) also stimulated pure marrow fibroblasts themselves. Analysis of the F-CM detected the presence of macrophage colony-stimulating factor (M-CSF), and low levels of interleukin 1 (IL-1) and interleukin 6 (IL-6), but no detectable levels of interleukin 3 (IL-3), interleukin 5 (IL-5), granulocyte-macrophage colony-stimulating factor (GM-CSF), or granulocyte colony-stimulating factor (G-CSF). Macrophages and endothelial cells, freed from other bone marrow components, required the F-CM if no other growth factors were added. We conclude that F-CM contains an autocrine factor, which the evidence suggests is IL-1, for bone marrow fibroblasts, and a paracrine factor (CSF-1) for macrophages and/or endothelial cells.


Asunto(s)
Médula Ósea/metabolismo , Factores Estimulantes de Colonias/biosíntesis , Hematopoyesis , Animales , Células de la Médula Ósea , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Medios de Cultivo , Fibroblastos/metabolismo , Ratones , Células Madre/citología
15.
J Cancer Res Clin Oncol ; 128(4): 223-30, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11935314

RESUMEN

PURPOSE: Cantharidin, a natural toxin, is the active substance of mylabris and has antitumor effects in man. Norcantharidin, the demethylated analogue of cantharidin, has been used in the treatment of patients with primary hepatoma and those with leukopenia in China. The present study was designed to investigate whether norcantharidin exerts cytotoxic activity against colorectal cancer cells by inducing apoptosis and to examine the possible mechanism in the phenomenon. METHODS: Inhibition of proliferation of norcantharidin on Colo205, HT-29, and SW480 colorectal cancer cells was determined by the trypan blue dye exclusion test. Apoptosis of norcantharidin-treated cells was determined by morphological analysis, agarose gel DNA electrophoresis, and quantitated by flow cytometry after staining with propidium iodide. Cell cycle and the cell surface expression of the CD95/CD95 ligand were evaluated by flow cytometry. Caspase 8-like protease and protein phosphatase 1 and 2A activities were also analyzed. RESULTS: Treatment with norcantharidin of colorectal cancer cells not only inhibited cell proliferation, but also induced apoptosis. Norcantharidin induced apoptosis mainly in two phases: rapid apoptosis in S-phase cells and delayed apoptosis in G2/M arrested cells. Treatment with norcantharidin resulted in an upregulation of the CD95 receptor and CD95 ligand on the cell surface. Furthermore, stimulation with anti-CD95 monoclonal antibody (mAb) resulted in further induction of apoptosis after treatment with norcantharidin. In addition, the apoptosis-inducing effect of norcantharidin was almost completely inhibited by anti-CD95 ligand mAb. Norcantharidin-treated cells showed the activation of caspase 8. Both zVAD-FMK (a broad range caspase inhibitor) and IETD-FMK (a caspase-8 inhibitor) showed apparent inhibition of the apoptosis-inducing effect. Norcantharidin did not show an inhibitory effect on protein phosphatase. CONCLUSIONS: These results suggest that norcantharidin triggers apoptosis in colorectal cancer cell lines via the activation of the CD95 receptor/ligand system, and that this agent may be useful for developing new therapeutic regimens for the treatment of colorectal carcinoma.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Neoplasias Colorrectales/patología , Glicoproteínas de Membrana/biosíntesis , Anticuerpos Monoclonales , Caspasa 8 , Caspasa 9 , Caspasas/metabolismo , Proteína Ligando Fas , Humanos , Glicoproteínas de Membrana/fisiología , Células Tumorales Cultivadas , Regulación hacia Arriba
16.
IEEE Trans Pattern Anal Mach Intell ; 6(4): 406-17, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21869209

RESUMEN

Based on a recursive process of reducing the entropy, the general decision tree classifier with overlap has been analyzed. Several theorems have been proposed and proved. When the number of pattern classes is very large, the theorems can reveal both the advantages of a tree classifier and the main difficulties in its implementation. Suppose H is Shannon's entropy measure of the given problem. The theoretical results indicate that the tree searching time can be minimized to the order O(H), but the error rate is also in the same order O(H) due to error accumulation. However, the memory requirement is in the order 0(H exp(H)) which poses serious problems in the implementation of a tree classifier for a large number of classes. To solve these problems, several theorems related to the bounds on the search time, error rate, memory requirement and overlap factor in the design of a decision tree have been proposed and some principles have been established to analyze the behaviors of the decision tree. When applied to classify sets of 64, 450, and 3200 Chinese characters, respectively, the experimental results support the theoretical predictions. For 3200 classes, a very high recognition rate of 99.88 percent was achieved at a high speed of 873 samples/s when the experiment was conducted on a Cyber 172 computer using a high-level language.

17.
IEEE Trans Pattern Anal Mach Intell ; 9(1): 91-102, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21869379

RESUMEN

In the tree classifier with top-down search, a global decision is made via a series of local decisions. Although this approach gains in classification efficiency, it also gives rise to error accumulation which can be very harmful when the number of classes is very large. To overcome this difficulty, a new tree classifier with the following characteristics is proposed: 1) fuzzy logic search is used to find all ``possible correct classes,'' and some similarity measures are used to determine the ``most probable class''; 2) global training is applied to generate extended terminals in order to enhance the recognition rate; 3) both the training and search algorithms have been given a lot of flexibility, to provide tradeoffs between error and rejection rates, and between the recognition rate and speed. A computer simulation of the decision trees for the recognition of 3200 Chinese character categories yielded a very high recognition rate of 99.93 percent and a very high speed of 861 samples/s, when the program was written in a high level language and run on a large multiuser time-sharing computer.

18.
Artículo en Inglés | MEDLINE | ID: mdl-21869088

RESUMEN

A multistage classifier with general tree structure has been developed to recognize a large number of Chinese characters. A simple and efficient method of classifying the characters was achieved by choosing the best feature at each stage of the tree. The features used are Walsh coefficients obtained from two profiles of a character projected onto the X-Y orthogonal axes. Some algorithms for aligning the characters were compared and one of them was adopted in this recognition scheme. A high recognition rate of about 99.5 percent was obtained in an experiment with more than 3000 different Chinese characters.

19.
Chin Med J (Engl) ; 105(7): 544-8, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1451558

RESUMEN

The passages 0 and 3 purified human bone marrow fibroblast layers (FLs) were established by long-term liquid cultures. After 12-day coculture of stromal. cell-depleted marrow cell suspensions with passage 0 FLs, 68.33 +/- 4.04% of the hemopoietic colonies adhered to FLs was myeloid in nature and the other 31.67 +/- 4.04% was erythroid. There were still CFU-E (colony forming unit-erythroid), BFU-E (burst forming unit- erythroid), and CFU-GM (colony forming unit-granulocyte/macrophage) among the nonadherent cells. The media conditioned by passage 0 (F0-CM) and passage 3(F3-CM) FLs stimulated the growth of myeloid and erythroid (BFU-E) colonies. From these data, it is concluded that both FLs and the media conditioned by fibroblasts can stimulate myeloid and erythroid hemopoiesis.


Asunto(s)
Células de la Médula Ósea , Hematopoyesis , Células Madre Hematopoyéticas/citología , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Factores Estimulantes de Colonias/metabolismo , Células Precursoras Eritroides/citología , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos
20.
Sheng Li Xue Bao ; 53(4): 316-20, 2001 Aug.
Artículo en Zh | MEDLINE | ID: mdl-11930213

RESUMEN

In the present study, the effects of murine bone marrow endothelial cell conditioned medium (ECM) combined with flt3 ligand (FL) or/and thrombopoietin (TPO) on the proliferation of HPP-CFC and CFU-GM were investigated. Both ECM and the concentrated retentate of ECM (MW>10 kD) promoted the growth of CFU-GM and HPP-CFC, and this promoting effect was further enhanced by addition of FL or TPO. Using reverse transcriptase-polymerase chain reaction (RT-PCR) technique, the expression of FL and TPO mRNA was not found in murine bone marrow endothelial cells.


Asunto(s)
Células de la Médula Ósea/citología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Células Madre Hematopoyéticas/citología , Proteínas de la Membrana/farmacología , Trombopoyetina/farmacología , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Medios de Cultivo Condicionados , Medio de Cultivo Libre de Suero , Células Endoteliales/citología , Hematopoyesis/efectos de los fármacos , Ratones , ARN Mensajero
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