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3.
J Chem Phys ; 140(18): 184311, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24832274

RESUMO

In the present paper, thermal conductivity coefficient of high-temperature molecular and atomic gases with excited electronic states is studied using both the kinetic theory algorithm developed by authors earlier and the well known simple expression for the thermal conductivity coefficient proposed by Eucken and generalized by Hirschfelder. The influence of large collision diameters of excited states on the thermal conductivity is discussed. The limit of validity of the Eucken correction is evaluated on the basis of the kinetic theory calculations; an improved model suitable for air species under high-temperature conditions is proposed.

4.
Clin Infect Dis ; 40(2): 294-302, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15655750

RESUMO

BACKGROUND: In Israel, <0.06% of the general population is infected with human immunodeficiency virus (HIV), with a much higher prevalence among specific groups. These groups are distinguished demographically by risk behavior category and by virus subtype. We investigated transmission of drug resistance within groups to assess the impact of these factors. METHODS: Plasma samples from >15% of all patients with new diagnoses of HIV infection were randomly collected between June 1999 and June 2003. Sequences from 176 drug-naive patients included 20 of subtype A, 20 of subtype AE, 2 of subtype AC, 29 of subtype B, 100 of subtype C, and 5 of subtype F. RESULTS: Major drug resistance mutations (protease: L90M; reverse transcriptase: M41L, K103N, V106M, M184V, Y181S, G190A, L210W, T215Y/F, and K219R) were detected in 1 subject with A subtype, 3 with subtype B, and 9 with subtype C. In addition, 1 subject with A subtypes, 2 with subtype B, and 10 with subtype C had secondary mutations (protease: M46I; reverse transcriptase: A98G, K101Q, and V108I). Only 1 patient had mutations associated with >1 class of drugs. Among subjects who contracted HIV infection in Israel, 16 of 56 (1 of 7 with subtypes A or AE, 4 of 17 with subtype B, and 11 of 32 with subtype C; P=.7-1.0) carried resistant virus--a significantly higher proportion (P<.001) than in subjects infected in other countries (10 of 120 infected). CONCLUSIONS: Drug-resistant virus was detected in 14.8% of patients with new diagnoses of HIV infection but in 28.6% of patients known to have been infected in Israel. The implications include a need for pretreatment resistance testing and for better programs aimed at prevention of transmission, directed particularly at patients. We did not find significant differences in transmission of resistant virus between those infected with subtypes B and C, despite the different demographic background. A conclusive analysis and interpretation should await a more extensive study.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Adulto , Farmacorresistência Viral , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Protease de HIV/genética , HIV-1/genética , Humanos , Israel/epidemiologia , Masculino , Mutação , Filogenia , Polimorfismo Genético , RNA Viral/genética , DNA Polimerase Dirigida por RNA/genética
5.
AIDS ; 15(12): 1453-60, 2001 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-11504976

RESUMO

OBJECTIVE: To compare drug-resistant variants from untreated (naive) and treated patients infected with clade B or C virus. METHODS: Consecutive samples (165) from patients throughout Israel were analyzed. All those in the treated group were failing highly active antiretroviral therapy. RESULTS: There were 87 clade B (14 naive) and 78 clade C (20 naive) [corrected] with significant differences in the prevalence of known drug-resistance mutations between the clades: in naive patients in the protease region M36I 7% and 95% (P < 0.0001), K20R 0% and 27% (P = 0.063), A71V 18% and 0% (P = 0.063), M46I 0% and 13%, and V77I 18% and 0% (P = 0.063), respectively, and in the reverse transcriptase region A98G/S 0% and 20% (P = 0.12), respectively. Most clade C viruses also showed significant differences from clade B consensus sequence at additional protease sites: R41K 100%, H69K/Q 85%, L89M 95% and I93L 80% (P < 0.0001). There were also significant differences (P < 0.03 to < 0.0001) in treated patients in clades B and C: in the protease region L10I 40% and 12%, M36I 26% and 95%, L63P 67% and 40%, A71I 38% and 7%, G73I and V77I 18% and 0%, I84V 16% and 3%, and L90M 40% and 12%, respectively; in the reverse transcriptase M41L 41% and 17%, D67N 41% and12%, K70R 30% and 7%, T215Y 48% and 29%, K219Q 21% and 7%, and A98G/S 3% and 24%, respectively. CONCLUSION: Significantly differences between clade B and C viruses may be associated with development of differing resistance patterns during therapy and may affect drug utility in patients infected with clade C.


Assuntos
Variação Genética , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/enzimologia , Adolescente , Adulto , Idoso , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Criança , Pré-Escolar , Resistência Microbiana a Medicamentos/genética , Quimioterapia Combinada , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Genético , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico
6.
J Rheumatol ; 23(5): 939-41, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8724313

RESUMO

Common symptoms of the musculoskeletal system may occur as a rare presentation of an underlying malignancy. We describe a case of bronchogenic adenocarcinoma presenting as bilateral knee pain with arthritis due to bilateral metastases to the patellae. We also review the literature of patellar metastases.


Assuntos
Adenocarcinoma/secundário , Neoplasias Ósseas/secundário , Carcinoma Broncogênico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Patela , Adenocarcinoma/diagnóstico , Artrite/etiologia , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Patela/diagnóstico por imagem , Patela/patologia , Tomografia Computadorizada por Raios X
7.
Anat Embryol (Berl) ; 192(6): 557-71, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8751113

RESUMO

The postnatal development of the human primary motor cortex (area 4) was analyzed in 54 individuals ranging in age from birth to 90 years. Three parameters defining major cytoarchitectonic features (areal fraction, numerical density and mean area of cells) were measured in vertical columns extending from the pial surface to the border between cortex and underlying white matter. The data were compiled in profile curves that reveal or more detailed laminar pattern than the classical cytoarchitectonic descriptions. The most pronounced decreases in numerical density and areal fraction of Nissl-stained cells profiles during early postnatal ontogeny are observed in layer II. A clearly delineable layer IV, which is still recognizable in the newborn, disappears gradually during the first postnatal months. Although the width of the cortex as a whole increases during this period, layer V, the main source of pyramidal tract fibers, is the only lamina that also increases in relative thickness. The other layers remain stable or become relatively thinner. These results reveal specific laminar growth processes in area 4, which take place in parallel with the functional maturation of the cortical motor system.


Assuntos
Córtex Motor/citologia , Córtex Motor/crescimento & desenvolvimento , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Tamanho Celular , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade
8.
Zentralbl Allg Pathol ; 136(3): 255-64, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2356672

RESUMO

Alterations that occurred to the hemispheric structure as a result of experimentally induced meningeal fibrosis are reported in this paper. The rinsing function of cerebrospinal fluid was unilaterally stopped in the subarachnoidal space of domestic pigs by means of a viscous medium which contained soluble fatty acid salts. The animals were sacrificed 35 or 95 d after the experiments. Series of frontal sections of both cerebral hemispheres were planimetrically measured to establish differences between hemispheric cross-sections. Left-side deficits between 6 and 29% were recordable from all cases. Microscopic findings included large meningeal fibroses without visible changes to the cortex and others with destruction of cortical regions. Early alterations to cortical cytoarchitecture were investigated by means of automatic image analysis. Increased cell volume densities were recorded from the third and fifth cortical layers in cortex parts with no grossly visible alterations. The authors feel that the above alterations were primarily attributable to gradual occlusion of the lesser meningeal and cortical veins.


Assuntos
Encéfalo/patologia , Meninges/patologia , Animais , Fibrose , Lobo Frontal/patologia , Processamento de Imagem Assistida por Computador , Coelhos , Software , Suínos
9.
J Hirnforsch ; 31(3): 307-14, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2230098

RESUMO

For more than ten years automatic analysis procedures have been applied to explore cortical cytoarchitectonics of the brain. The investigations presented were carried out by a method described as "automatic morphocorticography". Attempts to find out quantitative criteria for early unilateral cortical alterations were carried out on a pig's brain with experimental cortical hemiatrophy caused artificially by wide spread meningeal fibrosis. Lateral differences of the relative volume density (V alpha) of all cells could be analysed for each cortical layer in detail by the automatically plotted morphocorticographs (MCG) of selected cortical parts from both hemispheres. Partial increases in the V alpha-values could be found in the whole cross-section of the cerebral cortex from the experimentally damaged hemisphere and the same value increases of between 10 and 15% were found in the 3rd an 5th cortical layer in particular. In contrast the mean values of the relative numerical cellular density in the whole cortical cross-section remained without significant changes. It can be concluded that the early alterations caused by this type of damage are predominantly due to changes in the neuropil structures.


Assuntos
Córtex Cerebral/citologia , Animais , Atrofia/patologia , Eletrofisiologia , Histocitoquímica , Suínos
10.
J Hirnforsch ; 30(1): 45-50, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2723411

RESUMO

Morphometric analysis of medial prefrontal cortex (layer VI) of rats treated daily with amphetamine in a dose of 2.5 mg/kg during 3 weeks was performed on the electron microscopic level. The efficacy of the amphetamine dosage was tested on behavioral observation. Synapses on dendritic shafts and spines were studied. The density of axo-dendritic synapses increase on 74%, while the density of synapses on spine's neck decreased on 53%. Most synaptic parameters measured in axo-dendritic (1) and axo-spinous (2) synapses increased significantly under the influence of 2.5 mg/kg dose of AMPH: area of presynaptic terminal increased on 35% (1) and 21% (2), length of postsynaptic density increased on 13% (1) and 12% (2), area of spine increase on 25%. But the density of synaptic vesicles near the active zone decrease (1-on 16.5%, 2-on 20%).


Assuntos
Anfetaminas/farmacologia , Lobo Frontal/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Sinapses/fisiologia , Animais , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Endogâmicos , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura
11.
J Hirnforsch ; 30(1): 51-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2723413

RESUMO

Morphometric analysis of Medial prefrontal cortex (layer VI) of rats treated daily with haloperidol in a dose of 0.1 mg/kg during 3 weeks was performed on the electron microscopic level. The efficacy of the haloperidol dosage was tested on the amphetamine psychosis model. Synapses on dendritic shafts and dendritic spines were studied. The density of synapses on dendritic shafts increased on 51%, while on spine's neck it decreased on 19%. There were significant changes of some synaptic parameters only in axo-dendritic synapses: area of presynaptic terminal decreased on 13% (p less than 0.05), length of postsynaptic density decreased on 15% (p less than 0.05), but the density of synaptic vesicles near the active zone increased on 10% (p less than 0.05).


Assuntos
Lobo Frontal/fisiologia , Haloperidol/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Sinapses/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Endogâmicos , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura
13.
Artigo em Russo | MEDLINE | ID: mdl-3188778

RESUMO

In animals three weeks of chronic amphetamine administration at 2.5 mg/kg daily doses elicited either functional or dense-type degenerative changes in nerve cells. The former were prevailing, the latter rarely occurred in the single cells. Morphometric analysis showed sharp density increase in axodendritic synapses and density decrease in axospinal ones at the spine's neck. Apart of this, the postsynaptic dense structures were expanded considerably in axodendritic and axospinal synapses. The authors believe this ultrastructural reorganization to result from the amphetamine-elicited dopaminergic hyperfunction.


Assuntos
Anfetamina/toxicidade , Lobo Frontal/efeitos dos fármacos , Animais , Lobo Frontal/ultraestrutura , Masculino , Neuroglia/efeitos dos fármacos , Neuroglia/ultraestrutura , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Ratos , Ratos Endogâmicos , Receptores Dopaminérgicos/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura , Fatores de Tempo
14.
Artigo em Russo | MEDLINE | ID: mdl-3314284

RESUMO

The authors have demonstrated the stability and reproducibility of the main characteristics (form, position, and relationship between the amplitudes of characteristic extreme values) of the profiles of three fields of the human cerebral cortex (10, 17, and 44) constructed according to the findings of automatic layer-by-layer scanning of a series of sections at an interval of about 15 mm along the layer and measurements of the main morphometric parameters (volumetric ratio, number and the mean area of sections). The study has shown quantitative differences of the cytoarchitectonic structures of fields 10 and 44 which are in agreement with notions about the peculiarities of their morphofunctional organization.


Assuntos
Córtex Cerebral/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Córtex Cerebral/fisiologia , Técnicas Citológicas , Morte Súbita/patologia , Humanos , Pessoa de Meia-Idade , Neurônios/citologia , Neurônios/fisiologia
15.
Biull Eksp Biol Med ; 101(3): 351-3, 1986 Mar.
Artigo em Russo | MEDLINE | ID: mdl-3485455

RESUMO

Cytoplasm organella segregation accompanies virtually all the changes occuring in embryonic and differentiated cells. The general scheme of mapping spatial distribution of cytoplasm texture parameters, realized using computed microscope LEITZ-T.A.S., allowed the imaging of geometrical relationship between yolk granules in the Rana Temporaria fertilized egg. The development of dorsoventral polarity in amphibian embryos was shown to be related to shape and location asymmetry of cytoplasm area containing clusters of yolk granules.


Assuntos
Citoplasma/ultraestrutura , Microscopia/instrumentação , Animais , Fase de Clivagem do Zigoto/ultraestrutura , Computadores , Feminino , Microscopia/métodos , Organoides/ultraestrutura , Rana temporaria , Televisão/instrumentação
16.
Artigo em Russo | MEDLINE | ID: mdl-2412373

RESUMO

The development of methods of an automatic structural analysis which uses modern methods of image processing has put forward requirements to standardize the staining of the preparations studied. However, the examination of autopsy material of the human brain shows that the standard procedure of staining does not always lead to standard results. The author presents a formalized description of changes in the quality of preparation staining at different stages, which is based on the measurement of distributions of the mean gradients of the section image obtained with the help of the textural analysis system TAS produced by Leitz. The procedure of adaptive staining based on this description is proposed, which will help to compensate for differences in tinctural properties of different samples of autopsy material.


Assuntos
Córtex Cerebral/patologia , Técnicas Histológicas , Coloração e Rotulagem/métodos , Humanos , Coloração e Rotulagem/normas
17.
Artigo em Russo | MEDLINE | ID: mdl-6548071

RESUMO

In the context of the development of approaches to a quantitative automated analysis of neural tissue, the use of television image analyzers seems to be fairly promising. A complex of programmes for the television analysis system (TAS) by "Leitz Company" has been developed to implement an automated analysis of cerebral cortex sections. At the first stage of investigation, the operator sets a plan of scanning the object in the interactive regimen and with a small magnification of the microscope. The second stage involves the focusing and discrimination of images, selection of objects for analysis and measurement of the principal stereological parameters of neurons with a large magnification and at an automatic regimen. The curves obtained of changes of the stereological characteristics of the cortex in relation to the distance to the surface are in good agreement with the cytoarchitectonic pattern observed. Thus, the use of the TAS allows for the effective automated processing of neuromorphological preparations.


Assuntos
Córtex Cerebral/citologia , Aumento da Imagem/instrumentação , Televisão/instrumentação , Animais , Desenho de Equipamento , Humanos , Microcomputadores , Microscopia/instrumentação , Neurônios/classificação , Neurônios/citologia , Software
18.
Biull Eksp Biol Med ; 91(5): 628-30, 1981 May.
Artigo em Russo | MEDLINE | ID: mdl-7260398

RESUMO

Application of a "Microvideomat" television image analyzer for quantitative evaluation of the Masson-Gamperl reaction enabled one to disclose slight shifts in the enterochromaffin cell population function of the rat duodenum. These shifts indicate intensification of the synthetic processes and accumulation of the secretory product 3 hours after a single food stimulation.


Assuntos
Sistema Cromafim/metabolismo , Duodeno/citologia , Células Enterocromafins/metabolismo , Histocitoquímica/instrumentação , Serotonina/metabolismo , Televisão , Animais , Computadores , Masculino , Fotometria/instrumentação , Ratos
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