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1.
Zhonghua Yi Xue Za Zhi ; 102(40): 3160-3166, 2022 Nov 01.
Artículo en Zh | MEDLINE | ID: mdl-36319170

RESUMEN

Nucleoside/Nucleotide analogues (NAs) are widely used for the antiviral treatment of chronic hepatitis B (CHB), however, it is difficult to achieve serum hepatitis B surface antigen (HBsAg) loss with NAs therapy. In recent years, several prospective trails have reported that HBsAg loss (functional cure or clinical cure) also occurs in a small number of hepatitis B e antigen (HBeAg) negative CHB patients who discontinued long-term treatment with NAs. Accordingly, the "stop-to-cure" strategy is proposed. Although the mechanism has not been fully elucidated, the known factors related to serum HBsAg loss with NAs withdrawal include HBV genotype, duration of NAs treatment, serum HBsAg and HBV RNA levels at end-of-treatment, and ethnic differences. In the review, we discuss the best time to stop NAs therapy, the potential markers for predicting relapse after cessation of NAs and the possible mechanism of "stop-to-cure" in HBeAg-negative CHB patients, and propose some suggestions on the time of retreatment.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B Crónica , Humanos , Antígenos e de la Hepatitis B , Estudios Prospectivos , Antivirales
2.
Zhonghua Yi Xue Za Zhi ; 102(9): 654-658, 2022 Mar 08.
Artículo en Zh | MEDLINE | ID: mdl-35249309

RESUMEN

Objective: To analyze the changes of patellar tendon elasticity quantitatively of amateur marathon runners by shear wave elastography (SWE) in a half marathon. Methods: A total of 47 amateur marathon runners (31 males and 16 females, aged from 20 to 44 years) were enrolled as the marathon group, and divided into dominant side (47 patellar tendons) and non-dominant side (47 patellar tendons). Grey-scale ultrasound and SWE were performed on the bilateral patellar tendons before and after the half marathon within 2 h and after a period of 1 week. Thirty healthy volunteers (18 males and 12 females, aged from 22 to 39 years) were enrolled as the control group, the SWE-values derived from the patellar tendon were collected and analyzed. Multivariate logistic regression was performed to analyze the relationship between the changes of SWE-values and running age as well as weekly amount of running. Results: None of any runners showed knee pain and sports injury during the test. The dominant side had a higher SWE-values than non-dominant side in marathon group before running [(55.1±15.7) kPa vs (43.8±15.9) kPa, P<0.05]. The marathon group had higher SWE-values than the control group both in dominant side [(55.1±15.7) kPa vs (18.5±3.7) kPa] and non-dominant side [(43.8±15.9) kPa vs (17.4±3.2) kPa], respectively, before running (P<0.05). The SWE-values increased significantly both in dominant side [(80.2±23.2) kPa vs (55.1±15.7) kPa] and non-dominant side [(76.5±26.6) kPa vs (43.8±15.9) kPa] 2 h after running in marathon group. After a week, the SWE-values were not statistically different from those before running (P>0.05). Multivariate logistic regression showed that running age and weekly amount of running were related factors leading to the increase of SWE-values after running. Conclusions: The patellar tendon of amateur marathon runners has higher SWE-values. SWE can dynamically evaluate the changes of patellar tendon during exercise and is helpful for runners in scientific training and avoiding sports injury.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Ligamento Rotuliano , Adulto , Elasticidad , Femenino , Humanos , Masculino , Carrera de Maratón , Ligamento Rotuliano/diagnóstico por imagen , Ultrasonografía , Adulto Joven
3.
Anaesthesia ; 76(9): 1224-1232, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34189735

RESUMEN

Identification of high-risk patients admitted to intensive care with COVID-19 may inform management strategies. The objective of this meta-analysis was to determine factors associated with mortality among adults with COVID-19 admitted to intensive care by searching databases for studies published between 1 January 2020 and 6 December 2020. Observational studies of COVID-19 adults admitted to critical care were included. Studies of mixed cohorts and intensive care cohorts restricted to a specific patient sub-group were excluded. Dichotomous variables were reported with pooled OR and 95%CI, and continuous variables with pooled standardised mean difference (SMD) and 95%CI. Fifty-eight studies (44,305 patients) were included in the review. Increasing age (SMD 0.65, 95%CI 0.53-0.77); smoking (OR 1.40, 95%CI 1.03-1.90); hypertension (OR 1.54, 95%CI 1.29-1.85); diabetes (OR 1.41, 95%CI 1.22-1.63); cardiovascular disease (OR 1.91, 95%CI 1.52-2.38); respiratory disease (OR 1.75, 95%CI 1.33-2.31); renal disease (OR 2.39, 95%CI 1.68-3.40); and malignancy (OR 1.81, 95%CI 1.30-2.52) were associated with mortality. A higher sequential organ failure assessment score (SMD 0.86, 95%CI 0.63-1.10) and acute physiology and chronic health evaluation-2 score (SMD 0.89, 95%CI 0.65-1.13); a lower PaO2 :FI O2 (SMD -0.44, 95%CI -0.62 to -0.26) and the need for mechanical ventilation at admission (OR 2.53, 95%CI 1.90-3.37) were associated with mortality. Higher white cell counts (SMD 0.37, 95%CI 0.22-0.51); neutrophils (SMD 0.42, 95%CI 0.19-0.64); D-dimers (SMD 0.56, 95%CI 0.43-0.69); ferritin (SMD 0.32, 95%CI 0.19-0.45); lower platelet (SMD -0.22, 95%CI -0.35 to -0.10); and lymphocyte counts (SMD -0.37, 95%CI -0.54 to -0.19) were all associated with mortality. In conclusion, increasing age, pre-existing comorbidities, severity of illness based on validated scoring systems, and the host response to the disease were associated with mortality; while male sex and increasing BMI were not. These factors have prognostic relevance for patients admitted to intensive care with COVID-19.


Asunto(s)
COVID-19/mortalidad , Enfermedad Crónica/mortalidad , Mortalidad Hospitalaria , Unidades de Cuidados Intensivos , Factores de Edad , Comorbilidad , Cuidados Críticos , Humanos , Puntuaciones en la Disfunción de Órganos , Factores de Riesgo , SARS-CoV-2
4.
Zhonghua Gan Zang Bing Za Zhi ; 27(11): 910-912, 2019 Nov 20.
Artículo en Zh | MEDLINE | ID: mdl-31941250

RESUMEN

The 2019 European Association for the Study of the Liver (EASL) Clinical Practice Guidelines (hereinafter referred to as the EASL Guidelines) extracted the required evidence from detailed research materials, and rigorously graded and condensed the varying strengths of evidence into 32 recommendations and 14 statements (recommendations and reminders) for drug-induced Liver Injury (DILI). This guideline has important reference values for helping clinicians to further improve their understanding of DILI and the level of clinical diagnosis, treatment and prevention; however, there are still several issues worthy of further discussion.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Guías de Práctica Clínica como Asunto , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/terapia , China , Humanos , Sociedades Médicas
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(12): 1276-1280, 2018 Dec 06.
Artículo en Zh | MEDLINE | ID: mdl-30522230

RESUMEN

Objective: To study the effect of nutrition intervention on the body composition and blood glucose in newly diagnosed patients with type 2 diabetes mellitus complicated with overweight and obesity. Methods: A total of 84 newly diagnosed patients with type 2 diabetes mellitus complicated with overweight and obesity were selected from the department of endocrinology in China-Japan Friendship Hospital from April 2015 to December 2016. Basic information and body composition of these patients were collected and measured. Also the food frequency questionnaire (FFQ) was used to investigate the dietary status in the past month, and calculate the intake of energy, three major nutrients and dietary fiber. All patients received nutrition intervention by nutritionist for three months as requested by Diabetes guidelines. After 3-month intervention, blood glucose, body composition and dietary status were examined again. Relevant indicators of patients were compared before and after the intervention. All patients were divided into three groups according to the degree of body mass index (BMI)'s change: <5%, 5%-10% and >10%. The differences of body weight, muscle, body fat rate, visceral fat index and blood glucose level among three groups were quantified. Results: There were 53 male patients with age (41.5±8.9) years and HbA1c (7.5±0.4)%, and 31 female patients with age (40.1±8.5) years with HbA1c (7.6±0.5)%. The intake of energy, carbohydrate and fat of patients were significantly decreased (P<0.05) and dietary fiber was significantly increased (P<0.05) after nutrition intervention. The body weight, muscle mass, fat mass and visceral fat index were also significantly decreased (P<0.05). The average decrease of fat was about 2.8 kg accounting for 73.7% (2.8 kg/3.8 kg) of the total weight loss. The body fat rate decreased from (31.2±3.1)% to (28.8±3.2)% (P<0.05). The fasting blood glucose and postprandial blood glucose were both decreased significantly after intervention (P<0.05). Among three BMI decreased groups, there was no significant difference in body weight and muscle mass (P>0.05), but a significant difference in body fat rate and visceral fat index (P<0.05). The body fat rate, visceral fat index, fasting blood glucose and postprandial blood glucose had more decreases with the greater amount of weight loss (P<0.05). Conclusion: The three-month nutrition intervention could change the dietary habit and components of patients with type 2 diabetes mellitus by reducing the blood glucose, body fat rate and visceral fat index significantly. The degree of reduced BMI is positively related to the decrease of fasting blood glucose and postprandial blood glucose.


Asunto(s)
Diabetes Mellitus Tipo 2/dietoterapia , Sobrepeso/complicaciones , Adulto , Glucemia , Composición Corporal , China , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Resultado del Tratamiento
6.
Zhonghua Gan Zang Bing Za Zhi ; 25(7): 500-505, 2017 Jul 20.
Artículo en Zh | MEDLINE | ID: mdl-29055987

RESUMEN

The optimal clinical outcomes are the original intention and base to form the short-term, long-term and special goals of antiviral treatment in patients with hepatitis B virus (HBV) infection. The immediate indicators for assessment of antiviral clinical outcomes, which usually need prolonged follow-up, include the liver histopathological changes, the occurrence and severity of liver cirrhosis and hepatocellular carcinoma (HCC), mortality and survival rates, survival time and life quality, prevention rates of Mother-to-Child Transmission and HBV reinfection after liver transplantation, etc.


Asunto(s)
Hepatitis B , Neoplasias Hepáticas , Antivirales , Carcinoma Hepatocelular , Virus de la Hepatitis B , Humanos , Cirrosis Hepática , Trasplante de Hígado , Recurrencia Local de Neoplasia , Resultado del Tratamiento
7.
Zhonghua Gan Zang Bing Za Zhi ; 25(7): 481-484, 2017 Jul 20.
Artículo en Zh | MEDLINE | ID: mdl-29055983

RESUMEN

Chronic hepatitis B is a serious public health issue in China. The clinical management of hepatitis B is effective with the emergence of antiviral agents. The outcome of long-term therapy and nucleos(t)ide analogues stopping rules are currently unresolved issues and unmet needs. Thus, we need to pay more attention to clinical research to build large-sample and long-term follow-up cohorts and begin with the end in mind. We believe that the way to resolve the issues above will be found with the efforts of generations.


Asunto(s)
Hepatitis B , Antivirales , China , Antígenos e de la Hepatitis B , Virus de la Hepatitis B , Resultado del Tratamiento
8.
Zhonghua Yi Xue Za Zhi ; 96(34): 2722-2725, 2016 Sep 13.
Artículo en Zh | MEDLINE | ID: mdl-27667105

RESUMEN

Objective: The aim was to explore the strategy and clinical value of laparoscopic transection of median hepatic fissure (MHF) in difficult laparoscopic liver resections. Methods: First the MHF was located and marked, then the transection plane of the MHF was set. Next, the laparoscopic Multifuctional Operative Dissector (LPMOD) and the technique of curettage and aspiration were utilized to transect the liver beginning from the middle portion of the gallbladder fossa, in a caudal-to-cranial and anterior-to-posterior direction, until the clear exposure of the anterior surface of the intrahepatic inferior vena cava. Transection of the MHF was accurately achieved. Finally, dissection of the second and third porta hepatis were carefully performed and mobilization of the transected liver was achieved. This technique of laparoscopic transection of MHF was successfully performed in 13 patients in difficult laparoscopic liver resections. Results: Between April 2014 and August 2015, 13 patients received the technique of laparoscopic transection of MHF in difficult laparoscopic liver resections, including 10 cases of laparoscopic right hepatectomy, two cases of laparoscopic left hepatectomy and one case of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). The maximum size of the transected tumor was 15 centimeter. Duration of surgery was 240-430 min[Mean, 324.4±50.0]; the time for transection of the MHF was 40-118 min[mean, 66.4±22.7]. Blood loss was 200-2 000 ml[583.3±452.9]. The length of postoperative hospital stay was 6-25 days[mean, 13.2±5.2]. Seven patients received intraoperative transfusions. No postoperative intraabdominal bleeding, liver failure or other severe postoperative complications occurred. No perioperative death occurred. Conclusions: Application of laparoscopic transection of the MHF in difficult laparoscopic liver resections can help to clearly expose the second and third porta hepatis, especially in patients who have huge tumors and poor exposure for hepatic dissection. Moreover, precise location and transection of the MHF remains very important strategies of applying this technique.


Asunto(s)
Hepatectomía , Hepatopatías/cirugía , Legrado , Disección , Humanos , Laparoscopía , Tiempo de Internación , Ligadura , Vena Porta , Complicaciones Posoperatorias , Periodo Posoperatorio , Vena Cava Inferior
9.
Exp Brain Res ; 227(4): 477-86, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23625076

RESUMEN

While the process of hand preshaping during grasping has been studied for over a decade, there is relatively little information regarding the organization of digit contact timing (DCT). This dearth of information may be due to the assumption that DCT while grasping exhibits few regularities or to the difficulty in obtaining information through traditional movement recording techniques. In this study, we employed a novel technique to determine the time of digit contacts with the target object at a high precision rate in normal healthy participants. Our results indicate that, under our task conditions, subjects tend to employ a radial to ulnar pattern of DCT which may be modulated by the shape of the target object. Moreover, a number of parameters, such as the total contact time, the frequency of first contacts by the thumb and index fingers and the number of simultaneous contacts, are affected by the relative complexity of the target object. Our data support the notion that a great deal of information about the object's physical features is obtained during the early moments of the grasp.


Asunto(s)
Dedos/fisiología , Fuerza de la Mano/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Femenino , Humanos , Masculino , Adulto Joven
10.
Neuroscience ; 322: 78-93, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-26892297

RESUMEN

The subplate (SP) plays important roles in developmental and functional events in the neocortex, such as thalamocortical and corticofugal projection, cortical oscillation generation and corticocortical connectivity. Although accumulated evidence indicates that SP interneurons are crucial for SP function, the molecular composition of SP interneurons as well as their developmental profile and distribution remain largely unclear. In this study, we systematically investigated dynamic development of SP thickness and chemical marker expression in SP interneurons in distinct cortical regions during the first postnatal month. We found that, although the relative area of the SP in the cerebral cortex significantly declined with postnatal development, the absolute thickness did not change markedly. We also found that somatostatin (SOM), the ionotropic serotonin receptor 3A (5HT3AR), and parvalbumin (PV) reliably identify three distinct non-overlapping subpopulations of SP interneurons. The SOM group, which represents ~30% of total SP interneurons, expresses neuronal nitric oxide synthase (nNOS) and calbindin (CB) and colocalizes entirely with neuropeptide Y (NPY). The 5HT3AR group, which accounts for ~60% of the total interneuronal population, expresses calretinin (CR) and GABA-A receptor subunit delta (GABAARδ). The PV group accounts for ~10% of total SP interneurons and coexpressed GABAARδ. Moreover, distinct interneuron subtypes show characteristic temporal and spatial distribution in the SP. nNOS(+) interneurons in the SP increase from the anterior motor cortex to posterior visual cortex, while CR(+) and CB(+) interneurons the opposite. Interestedly, the majority of GABAARδ(+) neurons in SP are non-GABAergic neurons in contrast to other cortical layers. These findings clarify and extend our understanding of SP interneurons in the developing cerebral cortex and will underpin further study of SP function.


Asunto(s)
Neuronas GABAérgicas/citología , Neuronas GABAérgicas/fisiología , Interneuronas/citología , Interneuronas/fisiología , Neocórtex/citología , Neocórtex/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Calbindinas/metabolismo , Recuento de Células , Técnicas de Sustitución del Gen , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones Transgénicos , Neocórtex/metabolismo , Neuropéptido Y/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Tamaño de los Órganos , Parvalbúminas/metabolismo , Receptores de GABA-A/metabolismo , Receptores de Serotonina 5-HT3/genética , Receptores de Serotonina 5-HT3/metabolismo , Somatostatina/metabolismo
11.
Methods Enzymol ; 289: 571-87, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9353739

RESUMEN

The peptide-amphiphiles described here provide a simple approach for building stable protein structural motifs using peptide head groups. One of the most intriguing features of this system is the possible formation of stable lipid films on solid substrates, or the use of the novel amphiphiles in bilayer membrane systems, where the lipid tail serves not only as a peptide structure-inducing agent but also as an anchor of the functional head group in the lipid assembly. The peptide-amphiphile system potentially offers great versatility with regard to head and tail group composition and overall geometries and macromolecular structures. For building materials with molecular and cellular recognition capacity, it is essential to have a wide repertoire of tools to produce characteristic supersecondary structures at surfaces and interfaces.


Asunto(s)
Pliegue de Proteína , Proteínas/química , Diseño de Fármacos , Ingeniería de Proteínas
12.
Biotechnol Prog ; 14(2): 332-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9548788

RESUMEN

Zeolite A and calcium phosphate modified Zeolite A have been shown to be a new effective packing material in ion exchange chromatography for the purification of immunoglobulin G (IgG) from binary mixtures and mouse ascites fluid. This study was to determine the effectiveness of purifying IgG using Zeolite X and dealuminated Zeolite X with twice the pore size of Zeolite A. Binary mixtures (IgG-albumin and IgG-transferrin) and a mouse ascites fluid were purified in Zeolite X (in Na+, K+, or NH4+ form) chromatographic columns and with dealuminated Zeolite X under a variety of operational conditions. The biological activity of the purified IgG from the mouse ascites fluid was confirmed by ELISA. The characteristics of zeolites in the present study suggest that functional groups of a protein displace the cations of zeolites near the crystal surfaces and create a different strength of affinity. The study demonstrated that Zeolite X and dealuminated Zeolite X are also promising new packing materials for the purification of IgG from biological materials.


Asunto(s)
Albúminas/aislamiento & purificación , Líquido Ascítico/química , Inmunoglobulina G/aislamiento & purificación , Transferrina/aislamiento & purificación , Zeolitas , Animales , Fraccionamiento Químico , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Ratones , Peso Molecular
13.
World J Gastroenterol ; 3(2): 121-2, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-27041969

RESUMEN

AIM: To investigate the relationship between the loss of heterozygosity (LOH) of microsatellites on the deleted in colorectal carcinoma (DCC) gene and prognosis of colorectal adenocarcinoma. METHODS: A retrospective study of 58 colorectal adenocarcinoma cases with follow-up data and paired control normal mucosal tissues from 1983 to 1985 from files from the West China University of Medical Sciences Department of Pathology was carried out by PCR microsatellite analysis. Sixteen, 35, and seven cases had well-, moderately, and poorly differentiated tumors, respectively; 11, 30, and 17 cases were staged as Dukes' A, B, and C, respectively. RESULTS: LOH of DCC microsatellites was detected in 18 cases (31.0%). The 5-year survival rate between LOH-positive and LOH-negative patients was 44.4% and 77.5%, respectively (P < 0.05). The results suggest that LOH of DCC microsatellites correlate with prognosis but not with differentiation (P > 0.05) and Dukes' stage (P > 0.05) in colorectal adenocarcinoma. CONCLUSION: LOH of DCC microsatellites may be a marker of malignancy. Combined with the traditional prognostic indicators, LOH can predict prognosis of colorectal adenocarcinoma.

14.
ASAIO J ; 47(3): 293-301, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11374776

RESUMEN

A mathematical model describing the pressure-volume relationship of the Novacor left ventricular assist system (LVAS) was developed. The model consists of lumped resistance, capacitance, and inductance elements with one time varying capacitor to estimate the cyclic pressure generation of the pump using pump volume measurement. The ejection and filling portions of the pump cycle were modeled with two separate functions. The corresponding model parameters were estimated by least squares fit to experimental data obtained in the laboratory. Pressure and volume waveforms obtained from the model were compared with data obtained from laboratory tests and from patients. It performed well in simulating pump operation throughout the entire cycle. This model can be used for the evaluation of LVAS performance, for on-line estimation of an LVAS patient's cardiovascular parameters, for pump controller development, and as a tool for engineer training.


Asunto(s)
Corazón Auxiliar , Hemodinámica , Modelos Cardiovasculares , Flujo Pulsátil , Humanos , Diseño de Prótesis
15.
Am J Chin Med ; 25(1): 21-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9166994

RESUMEN

The aim of this study was to investigate the effects of moxibustion at the meridian points BL-15 (Xin-shu) and BL-27 (Xiao-chang-shu) on renal function, systolic blood pressure, plasma levels of renin activity, aldosterone and atrial natriuretic peptide in spontaneously hypertensive rats. The results showed that urine volume increased significantly after moxibustion at the meridian points BL-15, but decreased at BL-27. Urinary excretion of Na+ decreased after moxibustion at the meridian points BL-15 and BL-27. Systolic blood pressure decreased after moxibustion at the meridian point BL-15. No effect was observed at BL-27. Plasma levels of aldosterone and renin activity increased significantly, but the levels of atrial natriuretic peptide decreased significantly after moxibustion at BL-15. Plasma levels of aldosterone and atrial natriuretic peptide increased significantly after moxibustion at the meridian points BL-27. These results suggest that the meridian points BL-15 and BL-27 are related to the regulation of renal function and the secretion of hormone with body fluid metabolism.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/terapia , Riñón/fisiología , Moxibustión , Puntos de Acupuntura , Aldosterona/sangre , Animales , Factor Natriurético Atrial/sangre , Cloruros/sangre , Creatinina/orina , Modelos Animales de Enfermedad , Electrólitos/orina , Hipertensión/fisiopatología , Masculino , Potasio/sangre , Radioinmunoensayo , Ratas , Ratas Endogámicas SHR , Ratas Sprague-Dawley , Renina/sangre , Sodio/sangre
16.
Aust Dent J ; 39(4): 247-51, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7945055

RESUMEN

Endodontic treatment often will require access through existing crowns. This study was undertaken to determine whether endodontic access cavity preparation affected the retention of crowns in anterior teeth and then to determine whether this retention can be regained by amalgam or post-retained amalgam restorations. Twenty extracted human incisors were mounted in acrylic blocks and prepared for crowns. Metal copings were fabricated and cemented with zinc phosphate cement and the forces required to displace the copings after various procedures were measured with a tensile testing machine. Retention values for all stages were compared with the initial retentive value for each coping without an access cavity which was set at 100 per cent. Group one specimens had the following means: copings with access cavity, 85.64 +/- 28.65 per cent of the initial values; amalgam flush with lingual dentine, 95.81 +/- 36.2 per cent; amalgam flush with coping, 114.89 +/- 34.5 per cent. Group two means were: copings with access cavity, 89.95 +/- 21.42 per cent; posts and amalgam, 177.37 +/- 77.5 per cent. Statistical analysis with the two sample t test showed that retention with post-retained amalgam restorations showed significantly higher values when compared with access cavities without restorations (p < 0.05). Retention values for post-retained restorations were significantly different from those just using amalgam. This study demonstrated that endodontic access cavities reduced the retention of the crowns, and subsequent restoration with amalgam or a post can regain the retention.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Coronas , Preparación de la Cavidad Dental , Retención de Prótesis Dentales , Restauración Dental Permanente , Incisivo , Tratamiento del Conducto Radicular , Amalgama Dental , Preparación de la Cavidad Dental/métodos , Diseño de Prótesis Dental , Humanos , Incisivo/cirugía , Ensayo de Materiales , Técnica de Perno Muñón , Tratamiento del Conducto Radicular/métodos , Estrés Mecánico , Resistencia a la Tracción , Cemento de Fosfato de Zinc
17.
Biomed Instrum Technol ; 31(5): 483-7, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9367047

RESUMEN

An axial-flow ventricular assist device (VAD) under development at the authors' facility is intended for use as a long-term implantable device. At high speeds axial-flow VADs can collapse the native ventricle and damage the heart muscle, lung tissue, and blood. A prototype algorithm was developed to maintain physiologic perfusion to the vital organs while preventing ventricular collapse, through analysis of the electrical current waveform of the motor. The premise of the control algorithm is that the hemodynamics of the patient are reflected in the shape of this waveform. This approach is intended to eliminate the need for invasive sensors, thus effectively using the pump itself as a transducer. The control algorithm regulates the speed of the pump by comparing the motor-current waveform with reference waveforms using a matched filter. The matched filter was evaluated by its classification and differentiation performance. Thus far, the authors have been able to classify the waveforms into one of the four physiologic regions (below, within, or above the optimal range, and ventricular suction) with over 90% reliability. Ongoing work is directed toward improving the detection of ventricular suction, as this condition must be strictly avoided.


Asunto(s)
Corazón Auxiliar , Algoritmos , Hemodinámica , Humanos , Diseño de Prótesis , Procesamiento de Señales Asistido por Computador , Transductores
18.
Eur J Pain ; 18(2): 162-73, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23868758

RESUMEN

BACKGROUND: In experimental early painful diabetic neuropathy, persistent hyperglycaemia induces dys-regulated sodium channel (Navs) expression in the dorsal root ganglion (DRG) and activates microglia in the spinal dorsal horn (SDH). However, information on diabetes-induced chronic neuropathic pain is limited. Therefore, we investigated abnormal Navs in the DRG and activated glial cells in the SDH of diabetic rats with chronic neuropathic pain. METHODS: Sixty-six rats were divided into diabetic and control groups: control rats (n = 18; 1 mL of normal saline via the right femoral vein) and diabetic rats [n = 48; 60 mg/kg streptozotocin (STZ) via the right femoral vein]. Hindpaw behavioural tests, Navs expression in the DRG, activation of glial cells in the SDH and the number of neurons in the SDH were measured at 1 and 2 weeks, and 1, 2, 3 and 6 months following saline and STZ administration. RESULTS: All diabetic rats exhibited hyperglycaemia from day 7 to 6 months. The diabetic rats decreased withdrawal threshold to mechanical stimuli but had blunted responses to thermal stimuli. Consistent up-regulation of Nav1.3 and down-regulation of Nav1.8 was observed. Microglial cells were activated early in the SDH and lasted for 6 months. A positive correlation between mechanical allodynia, Nav1.3 and microglial activation was observed. In addition, microglia activation in the SDH of STZ-induced diabetes was mediated, in part, by phosphorylation of p-38 mitogen-activated protein kinase. CONCLUSIONS: Diabetic rats showed hindpaw mechanical allodynia for 6 months. Persistent mechanical allodynia was positively associated with sustained increased activation of Nav1.3 and increased p38 phosphorylation in activated microglia.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Hiperalgesia/metabolismo , Microglía/metabolismo , Canal de Sodio Activado por Voltaje NAV1.3/metabolismo , Neuralgia/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Neuropatías Diabéticas/metabolismo , Modelos Animales de Enfermedad , Activación Enzimática , Masculino , Fosforilación , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba
19.
Transplant Proc ; 43(7): 2678-82, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21911145

RESUMEN

BACKGROUND: The use of dental implants in organ transplant patients remains controversial because of their altered wound healing and risk of serious infections. The aims of this study were to evaluate the long-term survival rate and related clincial parameters of dental implants among liver transplant patients on immunosuppressive medications. METHODS: We placed 45 implants in 13 liver transplant patients. All implants were sucessfully placed in the mandible or maxilla. The success rate, perimplant bone absorption (MBL), probing depth and Periotest values were measured at 3 months, as well as 1 and 3 years. RESULTS: At 3 years' follow-up, no implants were lost. MBL and Periotest values were within acceptable ranges without bleeding on probing or pathological probing depth. CONCLUSION: This series supports the use of dental implants in liver transplant patients who are stable under long-term immunosuppression.


Asunto(s)
Implantes Dentales , Trasplante de Hígado , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Cicatrización de Heridas
20.
Domest Anim Endocrinol ; 41(2): 57-66, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21600726

RESUMEN

The aim of this study was to show a stimulatory role in ovarian follicle development by prolactin (PRL) in chicken hens. In experiment 1, anti-PRL antibodies were generated in hen plasma by intramuscular administrations of recombinant PRL antigen. Egg laying remained at levels lower (P < 0.05) in the PRL-immunized group than in the BSA-immunized group of hens, whereas development of incubation was depressed in the former but not the latter group. Throughout the experiment, plasma PRL concentrations were lower in the PRL-immunized hens than in non-incubating control hens; LH concentrations were similar between the PRL- and BSA-immunized hens until the end of the experiment when LH was lower in the BSA-immunized hens (P < 0.05). In experiment 2, anti-PRL receptor (PRLR) antibodies were raised in hens with the use of immunizations against recombinant PRLR extracellular domain. Immunization against PRLR initially increased the egg-laying rate when measured under the short photoperiod (12 h) but blocked the laying rate increase that occurred in the BSA-immunized control hens when the photoperiod was extended from 12 to 16 h. The development of incubation behavior was not affected by immunization against PRLR nor was plasma PRL or LH concentration. In experiment 3, when the egg-laying rate was depressed in PRL immunization hens, developmental speed of large white follicles was found to be slower than in the BSA-immunized control hens (P < 0.05). These results indicate that immunization against PRL slows down ovarian follicular development and reduces hen egg-laying performance, suggesting that PRL plays a stimulatory role in ovarian follicular development in chicken hens.


Asunto(s)
Pollos/fisiología , Folículo Ovárico/fisiología , Oviposición/fisiología , Prolactina/fisiología , Receptores de Prolactina/fisiología , Animales , Femenino , Hormona Luteinizante/sangre , Hormona Luteinizante/fisiología , Progesterona/sangre , Progesterona/fisiología , Prolactina/sangre
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