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1.
Zhonghua Yi Xue Za Zhi ; 98(22): 1771-1774, 2018 Jun 12.
Artículo en Chino | MEDLINE | ID: mdl-29925157

RESUMEN

Objective: To investigate the value of stereotactic biopsy in the accurate diagnosis of lesions in the brain stem and deep brain. Methods: A total of 29 consecutive patients who underwent stereotactic biopsy of brainstem and deep brain lesions between May 2012 and January 2018 were retrospectively reviewed. The Cosman-Roberts-Wells (CRW) stereotactic frame was installed under local anesthesia. Thin-layer CT and MRI scanning were performed. Target coordinates were calculated by inputting CT-MRI data into the radionics surgical planning system. The individualized puncture path was designed according to the location of the lesions and the characteristics of the image. Target distributions were as follows: 12 cases of midbrain or pons, 2 cases of internal capsule, 3 cases of thalamus, 12 cases of basal ganglia. The biopsy samples were used for further pathological and/or genetic diagnosis. Results: Twenty-eight of the 29 cases (96.6%) were diagnosed accurately by histopathology and genomic examination following stereotactic biopsy. Pathological results were as follows: 8 cases of lymphoma, 7 cases of glioma, 4 cases of demyelination, 2 cases of germ cell tumor, 2 cases of metastatic tumor, 1 cases of cerebral sparganosis, 1 case of tuberculous granuloma, 1 case of hereditary prion disease, 1 case of glial hyperplasia, 1 case of leukemia. The accurate diagnosis of one case required a combination of histopathology and genomic examination. Undefined diagnosis was still made in 1 cases (3.45%) after biopsy. After biopsy, there were 2 cases (6.9%) with symptomatic slight hemorrhage, 1 case (3.45%) with symptomatic severe hemorrhage, and 1 cass (3.45%) with permanent neurological dysfunction. No one died because of surgery or surgical complications. Conclusions: Stereotactic biopsy is fast, safe and minimally invasive. It is an ideal strategy for accurate diagnosis of lesions in brain stem and deep brain.


Asunto(s)
Encéfalo , Biopsia , Neoplasias Encefálicas , Tronco Encefálico , Humanos , Estudios Retrospectivos , Técnicas Estereotáxicas
2.
Phys Chem Chem Phys ; 11(46): 10934-8, 2009 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-19924328

RESUMEN

The possibilities of vacancy-induced magnetism in perovskite BaTiO(3) are investigated by first-principles calculations. Calculated results show that both titanium and oxygen vacancies could induce magnetism, but the barium vacancy did not induce magnetism. New and interesting magnetic properties of half-metallic magnetism are found in BaTiO(3) induced by the Ti-vacancy. Based on the density of states and the spin charge density distribution of BaTiO(3), we discuss the different origins of magnetism induced by the partial spin-polarized O 2p states around Ti vacancies and the partially filled d-states Ti around the oxygen vacancies. The discrepancy between the magnetic moments in the cubic phase and the tetragonal phase is due to anisotropic spin polarization induced by structure distortions. Our calculations would enable exploring magneto-electric coupling in nonmagnetic ferroelectric oxides.

3.
Waste Manag ; 28(6): 1081-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17512717

RESUMEN

Sewage sludge ash has been widely applied to cementitious materials. In this study, in order to determine effects of nano-SiO(2) additives on properties of sludge/fly ash mortar, different amounts of nano-SiO(2) were added to sludge/fly ash mortar specimens to investigate their physical properties and micro-structures. A water-binding ratio of 0.7 was assigned to the mix. Substitution amounts of 0%, 10%, 20%, and 30% of sludge/fly ash (1:1 ratio) were proposed. Moreover, 0%, 1%, 2%, and 3% of nano-SiO(2) was added to the mix. Tests, including SEM and compressive strength, were carried out on mortar specimens cured at 3, 7, and 28 days. Results showed that sludge/fly ash can make the crystals of cement hydration product finer. Moreover, crystals increased after nano-SiO(2) was added. Hence, nano-SiO(2) can improve the effects of sludge/fly ash on the hydration of mortar. Further, due to the low pozzolanic reaction active index of sludge ash, early compressive strengths of sludge/fly ash mortar were decreased. Yet, nano-SiO(2) could help produce hydration crystals, which implies that the addition of nano-SiO(2) to mortar can improve the influence of sludge/fly ash on the development of the early strength of the mortar.


Asunto(s)
Carbono/química , Materiales de Construcción , Incineración , Material Particulado/química , Aguas del Alcantarillado/química , Dióxido de Silicio/química , Ceniza del Carbón , Conservación de los Recursos Naturales , Microscopía Electrónica , Nanopartículas
4.
Biomed Environ Sci ; 3(1): 113-9, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2331324

RESUMEN

A study on iron-deficiency anemia (IDA) in adolescence was conducted among 478 teen-age students in Shanghai. The study indicated that the intake of nutrients among the students was generally insufficient. The lack of protein, calcium, Vitamin A, Vitamin B1, and Vitamin B2 was more serious. The morbidities of IDA among male and female students were 15.8 and 32.6%, respectively, higher in the female group (P less than 0.01). The iron-deficiency sufferers among male and female students were 46.8 and 61.8%, respectively, also higher in the female group (P less than 0.01). The causes of IDA were analyzed by the method of stepwise regression. In a study of the effect of IDA on intelligence and physical development in adolescents, we found that there was no significant effect of IDA on intelligence quotient (IQ) and school performance. However, the speed and endurance capabilities of students of both sexes were correlated directly with hemoglobin level. In female students, the speed capability was correlated directly with the serum ferritin content. On the basis of these findings, a special 3-month school lunch program was initiated. The results indicate that a comprehensive, rational, and balanced diet is beneficial to hemoglobin, free erythrocyte porphyrin, and serum ferritin contents and improves adolescent development.


Asunto(s)
Anemia Hipocrómica/epidemiología , Dieta , Hierro/sangre , Estado Nutricional , Adolescente , Anemia Hipocrómica/dietoterapia , Anemia Hipocrómica/etiología , China , Escolaridad , Femenino , Servicios de Alimentación , Humanos , Inteligencia , Masculino , Factores Sexuales
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