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OBJECTIVE@#To identify target genes of transcription factor CCAAT enhancer-binding protein β (CEBPB) in acute promyelocytic leukemia cells induced by all-trans retinoic acid.@*METHODS@#A new strategy for high-throughput identification of direct target genes was established by combining chromatin immunoprecipitation (ChIP) with in vitro selection. Then, 106 potential CEBPB binding fragments from the genome of the all-trans retinoic acid (ATRA)-treated NB4 cells were identified.@*RESULTS@#Of them, 82 were mapped in proximity to known or previously predicted genes; 7 were randomly picked up for further confirmation by ChIP-PCR and 3 genes (GALM, ITPR2 and ORM2) were found to be specifically up-regulated in the ATRA-treated NB4 cells, indicating that they might be the down-stream target genes of ATRA.@*CONCLUSIONS@#Our results provided new insight into the mechanisms of ATRA-induced granulocytic differentiation.
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Humanos , Sitios de Unión , Proteína beta Potenciadora de Unión a CCAAT , Genética , Metabolismo , Diferenciación Celular , Genética , Línea Celular , Inmunoprecipitación de Cromatina , Ensayo de Cambio de Movilidad Electroforética , Regulación Neoplásica de la Expresión Génica , Leucemia Promielocítica Aguda , Genética , Metabolismo , Neutrófilos , Fisiología , Reacción en Cadena de la Polimerasa , Transducción de Señal , Tretinoina , FarmacologíaRESUMEN
Ureteral fibroepithelial polyp accompanied by intussusception is a rare occurrence. Currently, most ureteral polyps could be removed readily by ureteroscopy. Nevertheless, endoscopic resection can be difficult in patient with a large polyp, especially accompanied by an intussusception. We described our experience and laparoscopic technique for treatment of a symptomatic 63-year-old woman who presented with a pedunculated, 9-cm-long, left lower ureteral, fibroepithelial polyp accompanied by a 2-cm-long intussusception.
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Femenino , Humanos , Persona de Mediana Edad , Intususcepción , Patología , Cirugía General , Laparoscopía , Métodos , Pólipos , Patología , Cirugía General , Uréter , Patología , Cirugía GeneralRESUMEN
<p><b>OBJECTIVE</b>To study the effect of Itk down regulation on Jurkat cell proliferation and inflammatory cytokines production, and provide useful data for Itk as an attractive target for potential drugs.</p><p><b>METHODS</b>Three shRNAs against different region of Itk were constructed and cotransfected with pEGFP-C1-hItk. The shRNA, which can knock down Itk, was selected and packed into lentivirus. After Jurkat cells were transfected with shRNA lentivirus, the change of Itk protein expression, cell proliferation and cytokines production was observed.</p><p><b>RESULTS</b>Itk mRNA was reduced about 55% in Jurkat cells transfected with Itk-shRNA1, compared with that in control cells shRNAnon (P < 0.05). Knocking down Itk expression had a profound inhibitory effect on Jurkat cell proliferation. In addition, there was a substantial decrease in level of cytokines, such as IL-2, IL-5, IL-10 and IFN-gamma, produced by cell transfected with Itk-shRNA1.</p><p><b>CONCLUSION</b>Knocking down Itk expression can inhibit Jurkat cell proliferation and inflammatory cytokines production.</p>
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Animales , Humanos , Ratones , Proliferación Celular , Citocinas , Genética , Alergia e Inmunología , Regulación hacia Abajo , Técnicas de Silenciamiento del Gen , Interleucina-10 , Genética , Alergia e Inmunología , Interleucina-2 , Genética , Alergia e Inmunología , Interleucina-5 , Genética , Alergia e Inmunología , Células Jurkat , Biología Celular , Alergia e Inmunología , Proteínas Tirosina Quinasas , Genética , Alergia e InmunologíaRESUMEN
<p><b>OBJECTIVE</b>To screen the peptides that bind specifically to the hepatoma cells using phage display random peptides library.</p><p><b>METHODS</b>Three rounds of panning were conducted in vitro targeting HepG2 cell lines. In nude mice bearing HepG2 tumor, one round of panning was conducted, and 30 phage clones were randomly selected for sequence analysis to identify the consensus sequence. Immunocytochemistry and immunohistochemistry were performed to determine the specificity of the phages to the hepatoma cells.</p><p><b>RESULTS</b>After three rounds of panning in vitro and one round of panning in vivo, the phages binding to HepG2 cells were enriched. Sequence analysis of the randomly selected clones identified the peptide sequence VRKRSECLGAHD as the most frequent sequence. Immunocytochemistry and immunohistochemistry confirmed the specificity of the phage binding to the hepatoma cells.</p><p><b>CONCLUSIONS</b>Specific peptides against hepatoma cells can be obtained from a phage- display peptide library, which provides an experimental basis for developing therapeutic agents targeting hepatoma cells.</p>
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Animales , Humanos , Ratones , Carcinoma Hepatocelular , Metabolismo , Células Hep G2 , Neoplasias Hepáticas , Metabolismo , Trasplante de Neoplasias , Biblioteca de Péptidos , Péptidos , Metabolismo , Unión ProteicaRESUMEN
<p><b>OBJECTIVE</b>To prepare a stable water-based magnetic fluid.</p><p><b>METHODS</b>A water-based magnetic fluid was prepared by addition of polyvinylpyrrolidone (PVP) as the coating agent for the magnetic particles. After preparation of Fe3O4 by co-precipitation method, PVP was added for its coating, followed by ultrasonic agitation and purification.</p><p><b>RESULTS</b>The magnetic nanoparticles of homogeneously small size and water-based magnetic fluid were obtained, which had good dispersion in water with strong magnetism.</p><p><b>CONCLUSION</b>PVP can be used as a surfactant to stabilize the magnetic fluid.</p>
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Compuestos Ferrosos , Química , Magnetismo , Ensayo de Materiales , Nanopartículas , Química , Povidona , Química , Propiedades de Superficie , Tensoactivos , QuímicaRESUMEN
<p><b>OBJECTIVE</b>To prepare tegafur magnetic long-circulating thermosensitive liposomes and study its pharmacokinetics and targeting properties in rats.</p><p><b>METHODS</b>Tegafur magnetic long-circulating thermosensitive liposomes were prepared by reversed phase-ultrasound method and its concentration in various organs of rats were detected with high-performance liquid chromatography.</p><p><b>RESULTS</b>The average size of tegafur magnetic long-circulating thermosensitive liposomes was about 126 nm, which showed strong ferromagnetism and superparamagnetism. Eight hours after administration in rats, the AUC value of tegafur magnetic long-circulating thermosensitive liposome in the liver was 17.4 times of that of the free drug, and 3.9 times of that of tegafur long-circulating liposome. The concentrations of the thermosensitive liposome in the serum and kidney were lower than those of the free drug, with a liver-targeting ratio reaching 73.9% and obviously prolonged half-life than the free drug.</p><p><b>CONCLUSION</b>Tegafur complex liposome can obviously increase the drug concentration in the liver and decrease the nephrotoxicity of the drug in rats.</p>
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Animales , Femenino , Masculino , Ratas , Sistemas de Liberación de Medicamentos , Liposomas , Farmacocinética , Hígado , Metabolismo , Magnetismo , Nanopartículas , Distribución Aleatoria , Ratas Wistar , Tegafur , Farmacocinética , Distribución TisularRESUMEN
This paper introduces five dental X-ray machines which are manufactured with IGBT to realize high frequency, real-time sampling and PWM to ensure the closed-loop control for tube current and Anodes's high voltage. These five machines also use microcomputer and combined X-ray tube for precise control. The sets don't have high voltage outside. The error of tube voltage is less than 1% and exposure time is less than 3%. The photos of pulp cavity and surrounding tissue can be seen clearly. These sets surely meet the requirements of perspective use in clinical.
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Humanos , Diseño de Equipo , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Métodos , Radiografía DentalRESUMEN
<p><b>BACKGROUND</b>Checkpoint kinase 2 (CHK2) is a DNA damage-activated protein kinase which is involved in cell cycle checkpoint control. CHK2 gene could be a candidate gene for colorectal cancer susceptibility. But there are few systematic reports on mutation of CHK2 in colorectal cancer.</p><p><b>METHODS</b>The mutations of all 14 exons of CHK2 in 56 colorectal cancer cell lines were screened systematically, using denaturing high-performance liquid chromatography (DHPLC) to screen the mismatches of the CHK2 exons amplified products, and then the suspected mutant cell lines were scanned by nucleotide sequence analysis.</p><p><b>RESULTS</b>VACO400 in CHK2 exon 1a was suspected to have mutation by DHPLC and confirmed by sequence, but this was nonsense mutation. C106, CX-1, HT-29, SK01, SW480, SW620 and VACO400 in CHK2 exon 1b were confirmed to have the same nonsense mutation in 11609 A > G. DLD-1 and HCT-15 in CHK2 exon 2 were confirmed to have missense mutation R145W, which was heterozygous C > T missense mutation at nucleotide 433, leading to an Arg > Trp substitution within the FHA domain.</p><p><b>CONCLUSIONS</b>The CHK2 mutation in colorectal cancer is a low frequency event. There are just 10 cell lines to have sequence variations in all the 14 exons in 56 colorectal cancer cell lines and only DLD-1/HCT-15 had heterozygous missense mutation. These findings may give useful information of susceptibility of colorectal cancer as single nucleotide polymorphysim.</p>
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Humanos , Línea Celular Tumoral , Quinasa de Punto de Control 2 , Cromatografía Líquida de Alta Presión , Neoplasias Colorrectales , Genética , Daño del ADN , Mutación , Proteínas Serina-Treonina Quinasas , GenéticaRESUMEN
<p><b>OBJECTIVE</b>To investigate the expression of X-linked inhibitor of apoptosis protein (XIAP) in colorectal cancer tissues and investigate its correlation with the clinicopathological factors of the malignancy.</p><p><b>METHODS</b>Immunohistochemistry and RT-PCR was employed to detect the expression of XIAP in 87 colorectal cancer tissues.</p><p><b>RESULTS</b>XIAP mRNA expression was detected in 64.4% (56/87) of the colorectal cancer tissues, 49.4% (43/87) of the adjacent tissues, and in 11.4% (10/87) of the normal tissues, respectively. The cancer tissues showed significant greater positivity rate and higher expression level of XIAP mRNA than the adjacent and normal tissues. Immunohistochemistry also identified a significantly greater positivity rate for XIAP [70.1% (61/87)] in the colorectal cancer tissues. The pathological grade of the tumors was associated with the expression level of XIAP, whereas this association was not established between XIAP expression and the clinical stages, tumor position or lymph node metastasis.</p><p><b>CONCLUSION</b>XIAP may play an important role in the development of colorectal cancer, which might serve as a potentially useful tumor marker.</p>
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Colorrectales , Metabolismo , Patología , Inmunohistoquímica , Estadificación de Neoplasias , ARN Mensajero , Metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína Inhibidora de la Apoptosis Ligada a X , MetabolismoRESUMEN
OBJECTIVE@#To evaluate the value of oral ferric ammonium citrate solution as a gastrointestinal contrast agent in diagnosing low-level obstructive jaundice.@*METHODS@#Thirty-six patients who were suspected of low-level obstructive jaundice were performed with magnetic resonance cholangiopancreatography (MRCP) and conventional MRI before and after the administration of oral ferric ammonium citrate solution. The diagnostic accuracy for evaluating the site and the cause of obstruction was compared with other diagnostic modalities.@*RESULTS@#The image qualities of single-slice and multi-slice MRCP were improved markedly. The accuracy of MRCP for evaluating the site of obstruction was 97.22%, which was superior to US (P<0.05). There were no significant differences among the MRCP, CT, and ERCP.@*CONCLUSION@#Oral ferric ammonium citrate solution can significantly improve the image quality of MRCP. FAC-MRCP is a simple, safe, and noninvasive technique with excellent accuracy in the diagnosis of low-level obstructive jaundice.
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Administración Oral , Pancreatocolangiografía por Resonancia Magnética , Métodos , Coledocolitiasis , Diagnóstico , Medios de Contraste , Compuestos Férricos , Ictericia Obstructiva , Diagnóstico , Compuestos de Amonio Cuaternario , Sensibilidad y EspecificidadRESUMEN
<p><b>OBJECTIVE</b>To evaluate the efficiency and safety of transhepatic arterial chemoembolization (TACE) with gemcitabine and carboplatin for the treatment of stage III hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>Sixty-one HCC patients were treated by TACE. During TACE, At first, intra-arterial infusion of carboplatin 300 mg/m2, then gemcitabine 1000 mg/m2 with 5-30 ml of ultra-lipoidal iodide oil emulsion was used for arterial embolization. The toxicity and hepatic damage were observed according to WHO anticancer drug toxicity criteria and Child-Pugh classification criteria, respectively. The survival time was also observed during follow-up.</p><p><b>RESULTS</b>The blood toxicity was bone marrow suppression presented as grade I leucopenia in 39.3%, grade II in 29.5%, grade III-IV in 18.0%. Grade II-III nausea and vomiting developed in 96.8% of the patients. Hepatic function damage became aggravated in 16 patients from A to B class, in 2 from A to C class, and in 6 from B to C class according to Child-Pugh classification criteria. The median survival time was 20 months with a range of 5 to 3 5 months.</p><p><b>CONCLUSION</b>Transhepatic arterial chemoembolization using carboplatin and mixture of gemcitabine with ultra-lipoidal iodide oil emulsion is safe and effective in the management of stage III hepatocellular carcinoma. This regimen can also improve their quality of life.</p>
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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Alanina Transaminasa , Sangre , Antimetabolitos Antineoplásicos , Antineoplásicos , Carboplatino , Carcinoma Hepatocelular , Sangre , Patología , Terapéutica , Quimioembolización Terapéutica , Desoxicitidina , Estudios de Seguimiento , Leucopenia , Neoplasias Hepáticas , Sangre , Patología , Terapéutica , Náusea , Estadificación de Neoplasias , Calidad de Vida , Inducción de Remisión , Tasa de SupervivenciaRESUMEN
<p><b>OBJECTIVE</b>To investigate the clinical efficacy of levonorgestrel-releasing intrauterine system (LNG-IUS) in the treatment of adenomyosis.</p><p><b>METHODS</b>Seventy patients with adenomyosis diagnosed according to clinical symptoms, magnetic resonance imaging (MRI) findings, laparoscopy and/or color-Doppler ultrasound imaging were treated with LNG-IUS, and the menstrual blood volume, dysmenorrhea, uterine volume, hepatic function and serum lipids were observed and evaluated.</p><p><b>RESULTS</b>In the first month of treatment, the menstrual blood size was reduced significantly to (35-/+12)% of that before treatment (P<0.01), and further to (7-/+4)% in the twelfth month (P<0.01). The average uterine volume was decreased by 18.6% (P<0.05) after the treatment, and dysmenorrhea was obviously relieved or completely disappeared alleviated. The condition of anemia was also improved rapidly, and no obvious side-effects on hepatic function and serum lipids were observed.</p><p><b>CONCLUSION</b>LNG-IUS is an effective and safe therapy for adenomyosis.</p>
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Adulto , Femenino , Humanos , Anticonceptivos Femeninos , Usos Terapéuticos , Endometriosis , Quimioterapia , Patología , Estudios de Seguimiento , Dispositivos Intrauterinos Medicados , Levonorgestrel , Usos Terapéuticos , Resultado del TratamientoRESUMEN
<p><b>BACKGROUND</b>Liver targeting drug delivery systems can improve the curative effects and relieve the cytotoxicity of the chemotherapy drugs in the treatment of liver diseases. Nanoparticles carrying therapeutic drugs are currently under hot investigation with great clinical significance. This study was aimed to investigate the different tissue distribution of the adriamycin polybutylcyanoacrylate nanoparticle (ADM-PBCA-NP) in the mice body after an injection via lateral tail vein, and to study the liver targeting effects of ADM-PBCA-NP in different diameters on normal mice liver.</p><p><b>METHODS</b>One hundred and eighty Kunming mice were randomly divided into 6 groups with 30 mice in each group (5 treatment groups of ADM-PBCA-NP in the different diameter ranges, non-conjugated free adriamycin injection was employed as the control group). A single dose of either conjugated or free adriamycin equaled 2 mg/kg of body weight was delivered via the tail vein. Five mice in each trail were sacrificed at 5, 15, 30 minutes, 1, 5 and 12 hours postinjection, respectively. The adriamycin concentrations in the respectively collected liver, kidney, spleen, heart, lung and plasma were demonstrated using a high performance liquid chromatography with fluorescence detector.</p><p><b>RESULTS</b>Compared with the control group, adriamycin was hardly detected in the heart muscle of the treatment groups (P < 0.05). The nanoparticle-conjugated adriamycin was cleaned up quickly from the kidney tissue. The adriamycin concentrations of the mice liver and spleen in the experimental groups were significantly higher than that in the control group, except for the group with the nanoparticles diameters of (22.3 +/- 6.2) nm (P < 0.05). The ADM-PBCA-NP in (101.0 +/- 20.3) nm diameter had the highest liver distribution, and the second highest adriamycin distribution in liver was the group of (143.0 +/- 23.5) nm diameter (P < 0.05). Moreover, adriamycin was released slowly in the liver during the detection period in the experimental groups. ADM-PBCA-NP in (22.3 +/- 6.2) nm diameter was not distributed in the tissue of the liver, kidney, heart, spleen, and lung.</p><p><b>CONCLUSIONS</b>ADM-PBCA-NP in 100 - 150 nm diameter range has the best liver targeting with a characteristic of slow medicine release. It also decreases the medicine distribution in the heart, kidney and lung. In the treatment of liver cancer, the polybutylcyanoacrylate nanoparticles system has a good liver targeting ability, which increases the anticancer activity and markedly decreases the toxicity of adriamycin.</p>
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Animales , Ratones , Antineoplásicos , Doxorrubicina , Sistemas de Liberación de Medicamentos , Enbucrilato , Hígado , Metabolismo , Nanoestructuras , Distribución TisularRESUMEN
<p><b>OBJECTIVE</b>To research the diagnosis and effective treatment of penetrating anorectal wounds.</p><p><b>METHODS</b>Retrospective analysis was done in 16 cases of penetrating anorectal wounds from 1985 to 2004. Debridement and suture of anorectal and vesical wounds, effective diversion of fecal and urinary stream and sufficient presacral drainage were performed in all cases.</p><p><b>RESULTS</b>All the 16 cases were cured. Among them, 2 cases with infection in presacral space were cured by sufficient drainage after operation, one case was cured by secondary repair after anal sphincter was repaired unsuccessfully and one case with rectovesical fistula was cured with conservative treatment. None of them suffered from complications such as anal stenosis, dysuria or impotence etc.</p><p><b>CONCLUSIONS</b>For penetrating anorectal wound, to master early recognition of concomitant injures, to select appropriate surgical intervention and to strengthen perioperative treatment are the keys to improve the curative effects.</p>
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Adolescente , Adulto , Humanos , Masculino , Persona de Mediana Edad , Canal Anal , Heridas y Lesiones , Recto , Heridas y Lesiones , Resultado del Tratamiento , Heridas Penetrantes , Diagnóstico , Cirugía GeneralRESUMEN
@#ObjectiveTo establish separate and appraisal methods of murine bone marrow mesenchymal stem cells (MSCs) and optimize the suitable conditions inducting MSCs directional differentiating into adipocytes in vitro.MethodsThe differential adherence to plastic was employed to separate MSCs. CFU-f and successive CFU-f cultures were employed to characterize the potent of proliferation and self-renewal of MSCs. The different adipogenic medium was used as induction for the differentiation of MSCs into adipocytes. The differentiated cells were identified by oil red O immunohistochemistry stain.ResultsThe purified MSCs showed the morphology of fibroblasts. It was found that the number of CFU-f formation depended on the planted number of MSCs. It showed a good relationship. Small type colony of CFU-f had little potent to re-clone, but almost 90% big type colony of CFU-f had the potent to regenerate CFU-f. The MSCs could directionally differentiated into adipocytes induced by different adipogenic medium. But more than 96% MSCs differentiated into mature adipocytes when induced by combined with dexamethasone (DM), 1-methy-3-isobutylxanthine (IBMX), insulin (IS) and indomethacin (ID).ConclusionThe purified MSCs can be harvested by method of differential adherence to plastic, and these MSCs have the potent of proliferation and self-renewal. Moreover, more than 96% MSCs can differentiate into mature adipocytes when induced by combined with DM, IBMX, IS and ID.
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Nanobiological technology is an important research field in nanotechnology and has extensive applications in medicine. Although initiated lately, application of nanobiological technology in medicine is advancing in good pace in China, mainly involves in fields including nano-scale pharmaceutical carrier, nanoscale diagnostic technology, nanobiomaterials, and nano-scale traditional Chinese medicine.
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Humanos , Nanomedicina , NanotecnologíaRESUMEN
<p><b>OBJECTIVE</b>To study the specific cellular immune response induced by a recombinant HBV DNA vaccine and evaluate the potential therapeutic effect of this vaccine against HBV.</p><p><b>METHODS</b>A series of HBV epitopes were screened and the optimal combinations of these gene fragments identified to construct the target gene HS which incorporated appropriate flanking sequences. HS was inserted in pVAX1 to construct the recombinant plasmid PVAX-HS. Generation of specific cytotoxic T lymphocytes (CTLs) induced by PVAX-HS in HLA-A2 mice was observed by 51Cr assay and the activity of the CTLs evaluated using ELISPOT assay.</p><p><b>RESULTS</b>PVAX-HS was constructed successfully, which induced specific CTLs with strong activities after immunization in mice as compared with the control group that yielded negative results.</p><p><b>CONCLUSION</b>PVAX-HS DNA immunization can induced specific cellular immune response in mice, suggesting the potential therapeutic effect of this HBV vaccine.</p>
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Animales , Humanos , Ratones , Vacunas contra Hepatitis B , Genética , Alergia e Inmunología , Virus de la Hepatitis B , Genética , Alergia e Inmunología , Inmunización , Métodos , Interferón gamma , Proteínas Recombinantes de Fusión , Genética , Alergia e Inmunología , Linfocitos T Citotóxicos , Alergia e Inmunología , Metabolismo , Vacunas de ADN , Genética , Alergia e InmunologíaRESUMEN
OBJECTIVE@#To investigate the adenovirus-mediated LacZ gene expression and the destination in different organs of SD rats after the intravenous injection in rats.@*METHODS@#Recombinant adenovirus vector containing LacZ was transferred to SD rats by injecting into the internal jugular vein. To identify the sites and periods of LacZ gene expression, X-gal staining was used to detect beta-gal level and period of LacZ gene expression of different organs in the transfected and non-transfected rats at different time intervals.@*RESULTS@#On the 1st day after the injection, the lung, liver, kidney, and spleen expressed some beta-gal; on the 3rd day after the injection, the lung, liver, kidney, and spleen expressed beta-gal obviously; their peak levels were on the 7th day; the beta-gal level decreased on the 14th day; beta-gal expression disappeared in the most organs except the lungs on the 28th day. In all animals, the brain did not express any beta-gal.@*CONCLUSION@#The adenovirus-mediated exogenous gene transfer in the internal jugular vein may be an effective approach of gene therapy in some diseases in the lung, liver, and kidney.
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Animales , Femenino , Masculino , Ratas , Adenoviridae , Genética , Técnicas de Transferencia de Gen , Terapia Genética , Inyecciones Intravenosas , Venas Yugulares , Operón Lac , Genética , Pulmón , Metabolismo , Distribución Aleatoria , Ratas Sprague-Dawley , Proteínas Recombinantes , Genética , TransfecciónRESUMEN
OBJECTIVE@#To bring forward a new method for automatic measurement of the translation and rotation of the eye movement.@*METHODS@#A centroid method, edge filter, and ellipse fitting were used to get the accurate position of the eye center. The rotation angle of the eye was determined by Fourier-Translation arithmetic operators.@*RESULTS@#The simulation image test and initial clinical experiment obtained a good precision.@*CONCLUSION@#This method can eliminate the influence of eyelid overlapping and illumination, which can measure the 3-dimensional eye movement accurately.