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1.
Zhonghua Yi Xue Za Zhi ; 101(20): 1458-1462, 2021 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-34044518

RESUMEN

Since the discovery of Epstein-Barr (EB) virus from the cultured cells in Burkitt lymphoma tissue in African children in 1964, we have gradually taken in its oncogenicity and the link between this virus and multiple mucocutaneous diseases. This review exhibits the process of EB virus infection and summarizes the clinical manifestations and varied prognosis of EB virus-associated skin diseases. The cases of common skin diseases including psoriasis, dermatomyositis, pemphigus, pemphigoid, parapsoriasis, atopic dermatitis, urticaria, systemic lupus erythematosus, scleroderma, panniculitis,erythema multiforme and vasculitis coinciding with EB virus infection were collected for the analysis of their EB virus-associated complications, treatments and outcomes.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Lupus Eritematoso Sistémico , Pénfigo , Enfermedades de la Piel , Niño , Herpesvirus Humano 4 , Humanos
2.
Phys Rev Lett ; 121(25): 256403, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30608778

RESUMEN

Emergent order at mesoscopic length scales in condensed matter can provide fundamental insight into the underlying competing interactions and their relationship with the order parameter. Using spectromicroscopy, we show that mesoscopic stripe order near the metal-insulator transition (MIT) of strained VO_{2} represents periodic modulations in both crystal symmetry and V-V dimerization. Above the MIT, we unexpectedly find the long-range order of V-V dimer strength and crystal symmetry become dissociated beyond ≈200 nm, whereas the conductivity transition proceeds homogeneously in a narrow temperature range.

3.
Phys Rev Lett ; 113(21): 216402, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25479508

RESUMEN

We report the simultaneous measurement of the structural and electronic components of the metal-insulator transition (MIT) of VO2 using electron and photoelectron spectroscopies and microscopies. We show that these evolve over different temperature scales, and are separated by an unusual monocliniclike metallic phase. Our results provide conclusive evidence that the new monocliniclike metallic phase, recently identified in high-pressure and nonequilibrium measurements, is accessible in the thermodynamic transition at ambient pressure, and we discuss the implications of these observations on the nature of the MIT in VO2.

4.
Phys Rev Lett ; 111(4): 047402, 2013 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-23931404

RESUMEN

The evolution of electron correlation in SrxCa1-xVO3 has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy, surface-sensitive photoemission spectroscopy, and ab initio band structure calculations. We show that the effect of electron correlation is enhanced at the surface. Strong incoherent Hubbard subbands are found to lie ∼20% closer in energy to the coherent quasiparticle features in surface-sensitive photoemission spectroscopy measurements compared with those from bulk-sensitive resonant soft x-ray emission spectroscopy, and a ∼10% narrowing of the overall bandwidth at the surface is also observed.

5.
Sci Rep ; 12(1): 14352, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35999350

RESUMEN

In this paper, an initial pressure adjustable explosion vessel was developed, and the effect of negative pressure, positive pressure (0.2-1.8 atm) different initial ambient pressure on the explosive shock wave generated by the explosion of explosives was studied. The relationships between the specific impulse, shock wave velocity, the amount of explosive gas products and the ambient pressure were analyzed for different initial pressure environments. It was found that: the overpressure of the blast shock wave decreases with the initial ambient pressure of the explosion, and there exists a negative pressure environment with a dramatic pressure decrease near 0.6 atm, defined as the super-sensitive negative pressure Pcr. The propagation velocity of an explosive wave increases with a decrease in the ambient pressure, and the propagation velocity at a pressure of 1.8 atm is four times less than the velocity at a pressure of 0.2 atm. The production of explosive gas products did not change. The greater the initial pressure of the environment where the explosive is located, the smaller the ratio of the gas generated by the explosion to the initial force gas in the explosion vessel is, and the greater the impact on the propagation of shock waves is. The maximum attenuation of the first specific impulse i1 is 72.97% and the maximum attenuation of the second specific impulse i2 is 72.39%. The experiments provide reference data for high-altitude military confrontation, high-altitude weapons and ammunition development, and deep-earth protection engineering.

6.
Ultrason Sonochem ; 53: 152-163, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30755391

RESUMEN

Recently, graphene decorated with various inorganic nanoparticles, such as Pt, Au, Ag, TiO2 and Fe3O4, among which Ag nanocomposites are good candidates for electronics, optics, electrochemistry and catalysis. However, preparation techniques for Ag nanoparticles/carbon matrix hybrids require tedious multi-step processes often involving toxic reducing agents/high temperatures which is not viable for scalable production. Here, a facile, one step and eco-friendly chemical co-reduction route was utilized to synthesis of a new nanocomposites by Ag nanoparticle anchored on reduced graphene oxide (rGO) at ambient temperature and combined first principles theoretical analyze their interfacial adsorption behavior, is reported. In this way, graphene oxide (GO) and Ag+ simultaneously reduced by thiourea dioxide (TD) without using any additional reduced reactants. Results indicated that GO was successfully reduced to rGO and well-dispersed Ag nanoparticles with sizes of 6-7 nm, anchored on the surface of rGO sheets. Reduction mechanism was attributed to the synergistic effect of its hydrolysis products in aqueous media. The experiment and theoretical calculation results obtained demonstrate this method to be applicable to the synthesis of other metals on rGO sheets in order to improve wettability and interfacial bonding between rGO and metal and may possibly find various forthcoming medicinal, industrial and technological applications.

7.
Mater Sci Eng C Mater Biol Appl ; 92: 268-279, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30184751

RESUMEN

Ti6Al4V (TC4) alloy has long been used as a bone interfacing implant material in dentistry and orthopedics due to its excellent biocompatibility and mechanical properties. The performance of TC4 can be further tailored by altering its grain structures. In this study, by means of sliding friction treatment (SFT), a nano-grained (NG) surface layer with an average grain size of ≤100 nm on the topmost surface was successfully generated on coarse-grained (CG) TC4 alloy sheet. It was shown that the NG surface possessed notably enhanced corrosion resistance in physiological solution compared to the CG surface, due to the formation of thicker and denser passive film facilitated by surface nanocrystallization. Additionally, the NG surface with stronger hydrophilicity favorably altered the absorption of anchoring proteins such as fibronectin (Fn) and vitronectin (Vn) that can mediate subsequent osteoblast functions. The in vitro results indicated that the NG surface exhibited remarkable enhancement in osteoblast adherence, spreading and proliferation, and obviously accelerated the osteoblast differentiation as compared to CG surface. Moreover, the NG surface also demonstrated good hemocompatibility. These findings suggest that SFT can endure bio-metals with advanced multifunctional properties for biomedical applications.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Nanoestructuras/química , Titanio/química , Titanio/farmacología , Adsorción , Fosfatasa Alcalina/metabolismo , Aleaciones , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Corrosión , Espectroscopía Dieléctrica , Técnicas Electroquímicas , Matriz Extracelular/metabolismo , Fibronectinas/química , Regulación de la Expresión Génica , Hemólisis/efectos de los fármacos , Humanos , Ensayo de Materiales , Minerales/química , Nanoestructuras/ultraestructura , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteogénesis/genética , Osteopontina/metabolismo , Adhesividad Plaquetaria/efectos de los fármacos , Vitronectina/química , Humectabilidad
8.
Poult Sci ; 86(4): 673-83, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17369538

RESUMEN

Developmental hormonal changes in Cobb 500 chick embryos and hatched chicks were determined by measuring plasma insulin, glucagon, insulin-like growth factor (IGF)-I, IGF-II, triiodothyronine, thyroxine, and glucose concentrations at different ages of embryogenesis and posthatch development. Plasma samples were obtained daily from 10 d of embryogenesis (10E) through 13 d posthatch and also at 17 and 21 d posthatch. A significant increase in plasma insulin was observed with increasing age from 10E to hatch. Plasma glucagon levels remained low until 17E, and then significantly increased approximately 3-fold at hatch, which corresponded with increasing plasma glucose levels during late embryo development. The plasma insulin to glucagon molar ratio of incubation from 14E to 17E ranged from 2 to 4, and was significantly higher than at any other time during incubation. These results indicate that insulin may be an important promoter of chick embryonic growth by the anabolic drive to promote protein deposition. Insulin and glucagon increased after hatch, which may be due to increased feed consumption and increased utilization of carbohydrates as the key energy source, compared with nutrients obtained through lipolysis and proteolysis in the embryos. Plasma triiodothyronine increased 4-fold from 18E to 20E, and thyroxine increased 3-fold from 16E to 19E. Insulin-like growth factor-I and IGF-II peaked at 14E. Insulin-like growth factor-I steadily increased above embryonic levels during the 3 wk of the posthatch period, whereas IGF-II levels steadily declined. These results suggest that IGF-II may be a more important functionary for chick embryonic development than IGF-I, and that IGF-I may be more important than IGF-II after hatch. The profile of metabolic hormones in the present study may help support an understanding of significant changes that occur in embryonic development and posthatch growth in chicks.


Asunto(s)
Pollos/sangre , Glucagón/sangre , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Insulina/sangre , Envejecimiento , Animales , Bovinos , Pollos/crecimiento & desarrollo , Femenino , Masculino , Tiroxina/sangre , Triyodotironina/sangre
9.
Blood Cancer J ; 7(8): e593, 2017 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-28841206

RESUMEN

The SOX4 transcription factor is a key regulator of embryonic development, cell-fate decision, cellular differentiation and oncogenesis. Abnormal expression of SOX4 is related to malignant tumor transformation and cancer metastasis. However, no reports are available regarding the clinical significance of SOX4 in acute myeloid leukemia (AML) and the role of SOX4 in leukemogenesis. In the current study, we found that AML patients with low bone marrow (BM) SOX4 expression had higher remission rates and longer overall survival than those with high SOX4 expression, regardless of age, white blood cell count at diagnosis, karyotype profile and NPM1/FLT3-ITD status. To elucidate the role of SOX4 in leukemogenesis, we generated a transgenic zebrafish model that overexpressed human SOX4 in the myeloid lineage Tg(spi1-SOX4-EGFP). These transgenic zebrafish showed, at 5 months of age, increased myelopoiesis with dedifferentiation in kidney marrow. At 9 months of age, their kidney structure was significantly effaced and distorted by increased infiltration of myeloid progenitor cells. These results suggest that SOX4 is not only an independent prognostic factor of AML, but also an important molecular factor in leukemogenesis.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Leucemia Mieloide Aguda/metabolismo , Mielopoyesis , Proteínas de Neoplasias/biosíntesis , Factores de Transcripción SOXC/biosíntesis , Proteínas de Pez Cebra/biosíntesis , Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Proteínas de Neoplasias/genética , Nucleofosmina , Factores de Transcripción SOXC/genética , Pez Cebra/genética , Proteínas de Pez Cebra/genética
10.
Sci Rep ; 7: 40039, 2017 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-28059150

RESUMEN

Multifunctional materials with more than two good properties are widely required in modern industries. However, some properties are often trade-off with each other by single microstructural designation. For example, nanostructured materials have high strength, but low ductility and thermal stability. Here by means of spark plasma sintering (SPS) of nitrided Ti particles, we synthesized bulk core-shell structured Ti alloys with isolated soft coarse-grained Ti cores and hard Ti-N solid solution shells. The core-shell Ti alloys exhibit a high yield strength (~1.4 GPa) comparable to that of nanostructured states and high thermal stability (over 1100 °C, 0.71 of melting temperature), contributed by the hard Ti-N shells, as well as a good plasticity (fracture plasticity of 12%) due to the soft Ti cores. Our results demonstrate that this core-shell structure offers a design pathway towards an advanced material with enhancing strength-plasticity-thermal stability synergy.

11.
Blood Cancer J ; 7(7): e588, 2017 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-28753595

RESUMEN

Suppressor of cytokine signaling 1 (SOCS1) protein, which encodes a member of signal transducers and activators of transcription-induced inhibitors, takes part in a negative regulation of cytokine signaling. The mechanism of SOCS1 in tumor carcinogenesis is complex and there have been no studies concerning the clinic-biologic implication of SOCS1 expression in acute myeloid leukemia (AML). Here, we first identified that higher bone marrow (BM) SOCS1 expression was closely associated with older age, FLT3-ITD, NPM1 and DNMT3A mutations, but negatively correlated with CEBPA mutation in patients with de novo AML. Compared to patients with lower SOCS1 expression, those with higher expression had lower complete remission rates and shorter overall survival. Further, higher expression of SOCS1 in the BM was an independent unfavorable prognostic factor irrespective of age, white blood cell, cytogenetics and gene mutations. Next, we generated zebrafish model overexpressing SOCS1 by spi1 promoter, which showed kidney marrow from adult SOCS1 zebrafish had increased myelopoiesis, myeloid progenitors and the kidney or spleen structure were effaced and distorted, mimicking leukemia phenotype. The SOCS1/FLT3-ITD double transgenic fish could further facilitate the leukemic process. The results indicate SOCS1 plays an important role in AML and its higher expression serves as a new biomarker to risk-stratify AML patients.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidad , Proteínas de Neoplasias/biosíntesis , Proteína 1 Supresora de la Señalización de Citocinas/biosíntesis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Animales Modificados Genéticamente , Biomarcadores de Tumor/genética , Supervivencia sin Enfermedad , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Nucleofosmina , Proteína 1 Supresora de la Señalización de Citocinas/genética , Tasa de Supervivencia , Pez Cebra , Proteínas de Pez Cebra/biosíntesis , Proteínas de Pez Cebra/genética
12.
Yi Chuan Xue Bao ; 17(1): 53-62, 1990.
Artículo en Zh | MEDLINE | ID: mdl-2196914

RESUMEN

E. coli dnaA46 fails to grow and form colonies at 40 degrees C; integrated with plasmid enables it to grow at 40 degrees C or 42 degrees C. In a previous paper we reported that the replication of chromosome initiated by the integrated F' plasmid was recA gene dependent. In this paper we report further the behavior of 5 plasmids and 2 phages as to their dependence of recA gene in the integrated state. It was demonstrated that the dependence or independence of recA gene is not related to the direction of replication of the plasmids or phages in the free state. The hypothesis that the function of recA gene is to convert the unidirectionally replicating machinery in the free state to the bidirectionally replicating one in the integrated state is refuted accordingly.


Asunto(s)
Cromosomas Bacterianos/metabolismo , Replicación del ADN , ADN Bacteriano/genética , Escherichia coli/genética , Genes Bacterianos , Plásmidos/genética , Lisogenia
13.
Yi Chuan Xue Bao ; 16(1): 56-66, 1989.
Artículo en Zh | MEDLINE | ID: mdl-2698232

RESUMEN

Mutant strain dnaA46 of Escherichia coli can be integratively suppressed by the F' plasmid. Upon introducing the recA56 mutation through transduction the suppressive integration strain (Sin) becomes unable to grow at 40 degrees C. By means of experiments of marker transfer, acridine orange sensitivity test, F' curing and mini-chromosome transformation it is concluded that the F' plasmid is always in an integrated state in the Sin strains and that the initiation of the replication of the bacterial chromosome is carried on by the integrated F' plasmid. The biosynthesis of DNA and protein of the Sin recA+ and Sin recA- strains at different temperatures were compared. It is concluded from the experimental results that the recA gene functions at the level of DNA replication. The recA gene is known to be the key gene in DNA recombination and SOS repair of DNA damage. The works reported here throw some light on the understanding of the function of the recA gene.


Asunto(s)
Cromosomas Bacterianos , Replicación del ADN , ADN Bacteriano/genética , Escherichia coli/genética , Genes Bacterianos/fisiología , Plásmidos/genética
14.
Zhonghua Jie He He Hu Xi Za Zhi ; 16(3): 135-7, 186, 1993 Jun.
Artículo en Zh | MEDLINE | ID: mdl-8242807

RESUMEN

The forced inspiratory volume-time curve in 25 health subjects with normal ventilation function and 25 patients with COPD were determined, and MMIF, FIV were calculated from the curves. The PImax was measured in the same 50 subjects by modified Blac method sequentially. A close relationship between MMIF, FIV and PImax was found. This result indicated that MMIF and FIV could be indeed for evaluation of strength of respiratory, muscles. Additional observations of MMIF, FIV and PImax in 50 patients with COPD before and after inotropic drugs, aminophylline and CNB, further proved the validity of MMIF and FIV.


Asunto(s)
Enfermedades Pulmonares Obstructivas/fisiopatología , Anciano , Aminofilina/uso terapéutico , Benzoatos/uso terapéutico , Cafeína/uso terapéutico , Combinación de Medicamentos , Femenino , Humanos , Capacidad Inspiratoria , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Mediciones del Volumen Pulmonar/métodos , Masculino , Persona de Mediana Edad , Ventilación Pulmonar/efectos de los fármacos
15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 24(1): 29-32, 2000 Jan.
Artículo en Zh | MEDLINE | ID: mdl-12583110

RESUMEN

The complex field cure instrument is a new medical instrument. The complex field is composed of several sorts of physical quantum fields. Mice and rats are continuously irradiated by the complex field for 20 days to 90 days. The result shows that WBC, Hb and PLT value of the animals irradiated with the instrument are more than the control group, and their biochemical index is normal. The internal organs of the experimental animals show no toxicity. The visceval coefficient (liver, spleen) of the experimental animals is more than the control group. The marrow micronucleas test is negative. The chromosome test show no distortion. All of the results have proved that the instrument produces no toxicity side effect. Application of the instrument is safe and reliable and it may increase immune function of the body.


Asunto(s)
Neoplasias/terapia , Modalidades de Fisioterapia/instrumentación , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de la radiación , Seguridad de Equipos , Femenino , Masculino , Ratones , Ratones Endogámicos , Modalidades de Fisioterapia/métodos , Ratas , Ratas Sprague-Dawley
16.
Clin Transl Oncol ; 14(4): 287-93, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22484636

RESUMEN

BACKGROUND: The purposes of the current study were to investigate whether overexpression of the PRL-1 is clinically relevant to hepatocellular carcinoma (HCC) and whether expression patterns of PRL-1 in HCC have diagnostic and prognostic value. METHODS: Immunohistochemistry analysis was performed for PRL-1 in 60 HCC samples. The data were correlated with clinicopathological features. The univariate and multivariate survival analyses were also performed to determine their prognostic significance. RESULTS: PRL-1 protein was overexpressed (83%) in HCC as compared with the adjacent normal tissue. PRL-1 expression was not influenced by chronic alcohol exposure or cirrhosis. High expression of PRL-1 was correlated with smoking (p=0.012), cirrhosis (p=0.047) and histological grade (p=0.055). The Kaplan-Meier survival curves showed that high PRL-1 expression related to a poor survival with statistical significance (I vs. III, p=0.010; II vs. III, p=0.001). Univariate analysis showed that PRL-1 expression was associated with tumour size, stage and PRL-1 score. Multivariate analysis revealed that the PRL-1 protein expression level was an independent factor for overall survival (HR, 5.367; 95% CI, 2.270-12.692; p=0.001). This is the first demonstration that the expression level of PRL-1 is correlated with tumour progression and prognosis in HCC. CONCLUSIONS: Along with other results, the PRL-1 protein is a candidate biomarker and a potential target for novel therapies against human HCC progression.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Proteínas de Ciclo Celular/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Proteínas de la Membrana/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Adolescente , Adulto , Anciano , Biomarcadores/metabolismo , Progresión de la Enfermedad , Femenino , Perfilación de la Expresión Génica/métodos , Humanos , Inmunohistoquímica/métodos , Hígado/patología , Masculino , Persona de Mediana Edad , Pronóstico , Resultado del Tratamiento
18.
Indoor Air ; 17(1): 2-18, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17257148

RESUMEN

There have been few recent studies demonstrating a definitive association between the transmission of airborne infections and the ventilation of buildings. The severe acute respiratory syndrome (SARS) epidemic in 2003 and current concerns about the risk of an avian influenza (H5N1) pandemic, have made a review of this area timely. We searched the major literature databases between 1960 and 2005, and then screened titles and abstracts, and finally selected 40 original studies based on a set of criteria. We established a review panel comprising medical and engineering experts in the fields of microbiology, medicine, epidemiology, indoor air quality, building ventilation, etc. Most panel members had experience with research into the 2003 SARS epidemic. The panel systematically assessed 40 original studies through both individual assessment and a 2-day face-to-face consensus meeting. Ten of 40 studies reviewed were considered to be conclusive with regard to the association between building ventilation and the transmission of airborne infection. There is strong and sufficient evidence to demonstrate the association between ventilation, air movements in buildings and the transmission/spread of infectious diseases such as measles, tuberculosis, chickenpox, influenza, smallpox and SARS. There is insufficient data to specify and quantify the minimum ventilation requirements in hospitals, schools, offices, homes and isolation rooms in relation to spread of infectious diseases via the airborne route. PRACTICAL IMPLICATION: The strong and sufficient evidence of the association between ventilation, the control of airflow direction in buildings, and the transmission and spread of infectious diseases supports the use of negatively pressurized isolation rooms for patients with these diseases in hospitals, in addition to the use of other engineering control methods. However, the lack of sufficient data on the specification and quantification of the minimum ventilation requirements in hospitals, schools and offices in relation to the spread of airborne infectious diseases, suggest the existence of a knowledge gap. Our study reveals a strong need for a multidisciplinary study in investigating disease outbreaks, and the impact of indoor air environments on the spread of airborne infectious diseases.


Asunto(s)
Microbiología del Aire/normas , Enfermedades Transmisibles/transmisión , Control de Infecciones/normas , Ventilación/normas , Movimientos del Aire , Infección Hospitalaria , Humanos
19.
Am J Epidemiol ; 148(9): 910-9, 1998 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9801022

RESUMEN

An industry-wide pulmonary morbidity study was undertaken to evaluate the respiratory health of employees manufacturing refractory ceramic fibers at five US sites between 1987 and 1989. Refractory ceramic fibers are man-made vitreous fibers used for high temperature insulation. Of the 753 eligible current employees, 742 provided occupational histories and also completed the American Thoracic Society respiratory symptom questionnaire; 736 also performed pulmonary function tests. Exposure to refractory ceramic fibers was characterized by classifying workers as production or nonproduction employees and calculating the duration of time spent in production employment. The risk of working in the production of refractory ceramic fibers and having one or more respiratory symptoms was estimated by adjusted odds ratios and found to be 2.9 (95 percent confidence interval 1.4-6.2) for men and 2.4 (95 percent confidence interval 1.1-5.3) for women. The effect of exposure to refractory ceramic fibers on forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), the ratio of the two (FEV1/FVC), and forced expiratory flow (liters/second) between 25 percent and 75 percent of the FVC curve (FEF(25-75)) was evaluated by multiple regression analysis using transformed values adjusted for height, by dividing by the square of each individual's height. For men, there was a significant decline in FVC for current and past smokers of 165.4 ml (p < 0.01) and 155.5 ml (p = 0.04), respectively, per 10 years of work in the production of refractory ceramic fibers. For FEV1, the decline was significant (p < 0.01) only for current smokers at 134.9 ml. For women, the decline was greater and significant for FVC among nonsmokers, who showed a decrease of 350.3 ml (p = 0.05) per 10 years of employment in the production of refractory ceramic fibers. These findings indicate that there may be important sex differences in response to occupational and/or environmental exposure.


Asunto(s)
Enfermedades Pulmonares/etiología , Fibras Minerales/efectos adversos , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/fisiopatología , Masculino , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/fisiopatología , Oportunidad Relativa , Prevalencia , Pronóstico , Pruebas de Función Respiratoria , Estudios Retrospectivos , Factores de Riesgo , Caracteres Sexuales , Encuestas y Cuestionarios , Estados Unidos/epidemiología
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