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1.
Am J Cardiol ; 74(11): 1095-8, 1994 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7977065

RESUMEN

Recent studies strongly support the prognostic importance of transient silent ischemia. Because patients with silent ischemia are at higher risk of a cardiac event, they are likely to benefit not only from control of symptoms, but also from treatment directed at prevention of ischemia. The efficacy of controlled-release metoprolol 200 mg once daily and diltiazem 60 mg 4 times daily was assessed in a randomized, double-blind, crossover study in 32 patients with proven coronary artery disease, predominantly asymptomatic myocardial ischemia, positive bicycle exercise test results, and > or = 5 minutes of asymptomatic ST-segment depression on a 24-hour screening ambulatory electrocardiogram (ECG). At the beginning and at the end of both 3-week treatment periods, an exercise test was performed and a 72-hour ambulatory ECG was recorded. Both active treatment periods were preceded by a 2-week placebo phase. Both treatments effectively reduced and postponed exercise-induced ST depression and reduced the total ischemic integral on the ambulatory ECG. Only metoprolol significantly reduced the mean number of ischemic episodes (54%, p = 0.0003, vs 31% for diltiazem, p = NS) and the mean duration of ischemia (51%, p = 0.012, vs 27% for diltiazem, p = NS) compared with baseline values. Metoprolol strongly blunted the morning and afternoon peak in the circadian distribution of ischemia, whereas diltiazem did not change the circadian distribution of ischemia at all.


Asunto(s)
Angina de Pecho/tratamiento farmacológico , Diltiazem/uso terapéutico , Metoprolol/uso terapéutico , Adulto , Anciano , Angina de Pecho/clasificación , Angina de Pecho/fisiopatología , Preparaciones de Acción Retardada , Diltiazem/administración & dosificación , Esquema de Medicación , Electrocardiografía Ambulatoria/efectos de los fármacos , Prueba de Esfuerzo/efectos de los fármacos , Femenino , Humanos , Masculino , Metoprolol/administración & dosificación , Persona de Mediana Edad , Método Simple Ciego , Resultado del Tratamiento
2.
Phytochemistry ; 55(4): 337-48, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11117882

RESUMEN

Data for 34 species of Plantago (Plantaginaceae), including subgen. Littorella (= Littorella uniflora), have been collected with regard to their content of iridoid glucosides and caffeoyl phenylethanoid glycosides (CPGs). In the present work, 21 species were investigated for the first time and many known compounds were found together with three new iridoid glucosides. Of these, arborescoside and arborescosidic acid, both of the uncommon type with an 8,9-double bond, were present in several species, while 6-deoxymelittoside was found only in P. subulata. The known compounds deoxyloganic acid, caryoptoside and rehmannioside D were isolated from the genus for the first time. The earlier reported occurrence of sorbitol in the family was confirmed, and this compound was shown by NMR spectroscopy to be the main sugar in the three species investigated for this. The combined data show that CPGs are present in all species investigated. With regard to the iridoids, the distribution patterns showed a good correlation with the classification of Rahn. Thus, aucubin is typical for the whole genus, while bartsioside and catalpol as well as 5-substituted iridoids are each characteristic for a subgenus in the family. Finally, the close relationship between Plantago and Veronica suggested by chloroplast DNA sequence analysis. could be corroborated by the common occurrence of the rare 8,9-unsaturated iridoids in these two genera.


Asunto(s)
Glucósidos/química , Plantago/química , Plantago/clasificación , Plantas Medicinales , Espectroscopía de Resonancia Magnética , Estructura Molecular , Especificidad de la Especie , Espectrometría de Masa Bombardeada por Átomos Veloces
3.
Rofo ; 128(1): 47-51, 1978 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-146660

RESUMEN

Spiral embolisation of a renal artery by the Gianturco method was carried out in eight patients. Our early experience with this technique is described. In seven patients it was possible to occlude arterial flow to the kidney completely, or almost completely. In one patient, faulty technique lead to an avoidable complication resulting in dislocation of the spiral into the femoral artery. The Gianturco method has advantages compared with other embolisation techniques, being simple, rapid, complete and permanent. In addition to its pre-operative and therapeutic use with renal tumours, the method can be used to abolish function in one or both kidneys.


Asunto(s)
Embolización Terapéutica/métodos , Arteria Renal , Adulto , Anciano , Aortografía/métodos , Estudios de Evaluación como Asunto , Femenino , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/terapia , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios
5.
Phys Rev Lett ; 73(16): 2188-2191, 1994 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-10056995
10.
Opt Lett ; 16(4): 241-3, 1991 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19773895

RESUMEN

We demonstrate the application of a type II Al(x)Ga((1-x))As/AlAs multiple quantum well as a fast saturable absorber in a hybridly mode-locked dye laser. Type II multiple quantum wells are promising for this application because of the fast recovery of the saturated absorption with picosecond or even subpicosecond time constants. We obtain almost transform-limited pulses as short as 0.9 psec for a type II sample with a recovery time of 2.3 psec.

11.
Z Parasitenkd ; 67(3): 261-71, 1982.
Artículo en Alemán | MEDLINE | ID: mdl-7136189

RESUMEN

We studied, under experimental conditions, the life cycle of Hepatozoon erhardovae in the tropical rat flea, Xenopsylla cheopis, light microscopically on coloured semi-thin sections. Fleas killed and prepared on the day of infection show stomachs filled with mice erythrocytes. Some monocytes are parasitized or show empty envelopes of gametocytes. The latter perforate the wall of the stomach, leaving behind empty parasitophorous vacuoles, and they migrate to the fat-body cells of the flea where they differentiate sexually and where they stay during the whole of their further sexual development. On days 2 and 3 post infection (p.i.) microgametes were observed with one flagellum each, as well as macrogametes in one and the same host cell. Fertilization is induced by gametogamy. During the various divisions of the nuclei on the days 8-12 p.i. droplet-like evaginations are formed on the pellicle of the oocyst from the peripherical chromatin condensations. Between days 12 and 14 p.i. the sporoblasts develop while the oocysts diminish in size. Between days 18 and 20 p.i. 16 sporozoites and a large residual body are differentiated in each sporoblast and surrounded by the sporocyst wall. The oocyst wall is preserved and forms sporocyst balls that are set free when the flea abdomen is pressed. The flea thus presents a highly infective vector; the intermediate host is infected after eating the flea.


Asunto(s)
Coccidios/crecimiento & desarrollo , Insectos Vectores/parasitología , Siphonaptera/parasitología , Animales , Diferenciación Celular , División Celular , Coccidios/citología , Cuerpo Adiposo/parasitología , Estómago/parasitología
12.
Opt Lett ; 11(6): 354-6, 1986 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19730629

RESUMEN

The occurrence of higher-order Fourier components in an originally sinusoidal free-carrier index grating produced in CdS by interference of two picosecond light pulses is demonstrated by simultaneously monitoring the decay of the first- and second-order diffraction intensity of a transparent probe pulse. A pronounced contribution with doubled period can be attributed to an exciton phase grating formed by binding of electrons and holes of the free-carrier grating.

13.
Berl Munch Tierarztl Wochenschr ; 109(6-7): 239-44, 1996.
Artículo en Alemán | MEDLINE | ID: mdl-8765541

RESUMEN

The tiny rice-grain like sarcocysts measure 3-5 x 1 mm, they are situated subfascially or in the depth of the muscles. The 50 nm thick irregular primary cyst wall forms towards the inside, small, bubble-like, less osmiophilic invaginations, which partly are concentrated in such a way, that a spongious like structure develops. The so surrounded protrusions are vertically or slightly inclined; they measure 4.25 x 1.7 microns and they are filled with compact fibrils. The cyst wall is underlaid by an average of 7.0 microns thick tape consisting of ground substance, from which an extensive septation runs to the center of the cyst. The so formed chambers are filled with lancet-like merozoites, which measure 15-20 x 1.8-2.5 microns. Their fine structure is identical with merozoites of all other sarcosporidia. A round vacuole, which is placed at the rear end of the merozoite near the nucleus seems to be a characteristic. Metrocytes are found rarely in the periphery and they are usually degenerated. In some cysts cystozoites, ground substance and protrusions show signs of lysis, the septation, however, remains usually unchanged.


Asunto(s)
Enfermedades de las Aves/parasitología , Músculos/parasitología , Sarcocystis/ultraestructura , Sarcocistosis/veterinaria , Animales , Aves , Masculino , Microscopía Electrónica , Sarcocistosis/parasitología
14.
Parasitol Res ; 76(5): 428-34, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2352920

RESUMEN

Investigations by scanning and transmission electron microscopy and freeze-etching revealed that eyes of adult Rhipicephalus evertsi mimeticus consist of a lens and photoreceptor cells, which are separated by an acellular layer and the hypodermis. The lens contains numerous pore channels, which open beneath the epicuticula of the outer portion, converge uninterrupted to the inner closure and end in approximately 420 pore fields. The inner closure of the lens is formed as a deep circular invagination. Beneath the hypodermis and perpendicular to the lens, a group of approximately 20 highly differentiated photoreceptor cells in a rosette-like arrangement is localized within the invagination of the lens. Each photoreceptor cell is characterized terminally by numerous, tightly packed and parallel-running microvilli, which are oriented perpendicularly to the lenticular pore channels.


Asunto(s)
Garrapatas/anatomía & histología , Animales , Ojo/ultraestructura , Femenino , Grabado por Congelación , Masculino , Microscopía Electrónica , Microscopía Electrónica de Rastreo
15.
Tierarztl Prax ; 24(5): 471-5, 1996 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-8999593

RESUMEN

In this epidemiological study of endoparasites 37 donkeys and 23 horses were included, which were examined coproscopically in regular intervals over a 15 month period. The animals derived from ten farms, in which regular prophylactic treatments with anthelmintics had been practiced at least for two years before this investigation. This study revealed the presence of at least twelve parasite species in donkeys, Eimeria leuckarti, Gasterophilus intestinalis, Fasciola hepatica, Anoplocephala perfoliata, Strongyloides westeri, Parascaris equorum, Dictyocaulus arnfieldi, Trichostrongylus axei and small strongyles, whose third stage larvae were characterized by eight, twelve, 16 or 18 intestinal cells. At least four parasite species were established in horses, E. leuckarti, G. intestinalis, P. equorum and small strongyles, whose third stage larvae were provided with eight intestinal cells. Infections with E. leuckarti, S. westeri and P. equorum were encountered in foals only and with D. arnfieldi in 16.2% of the donkeys. Incidences for small strongyles were highest, exhibiting neither age- and farm-dependent nor host species-dependent differences and amounting to 91.9% in donkey and 86.6% in horses. Considering all donkeys and horses, 35.1% and 43.5%, respectively, were infected at least with two, and 29.7% and 4.3%, respectively, with three parasite species. The species composition of the endoparasite fauna was always dominated by small strongyles. This field study indicates that the species composition of the endoparasite fauna in comparison to former investigations has not or only slightly changed in spite of widespread use of broad-spectrum anthelmintics for years. In addition, it has to be considered that donkeys continue to act as reservoir of D. arnfieldi and as source of infection for horses.


Asunto(s)
Equidae , Enfermedades de los Caballos , Enfermedades Intestinales/veterinaria , Enfermedades Parasitarias en Animales , Animales , Femenino , Alemania/epidemiología , Caballos , Enfermedades Intestinales/clasificación , Enfermedades Intestinales/epidemiología , Larva , Masculino , Enfermedades Parasitarias/clasificación , Enfermedades Parasitarias/epidemiología , Especificidad de la Especie
16.
Tierarztl Prax ; 24(1): 48-54, 1996 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-8720956

RESUMEN

In this epidemiological study 37 foals and mares were included, which have been coproscopically examined in regular intervals over a period lasting up to 13 months. The animals derived from nine breeding farms. In three of these farms no anthelmintics were used before this investigation, whereas in six farms at least three years before regular prophylactic treatments with anthelmintics have been carried out. This investigation revealed no differences in the species spectrum of endoparasites as well as in the incidence of infections as regards to the breeding farms with and without anthelmintic prophylaxis, however, significant differences between foals and mares. At least nine species were established in foals, Strongyloides westeri in 54.1% of the animals, Parascaris equorum in 64.9%, small strongyles, whose third stage larvae showed either eight or 12 intestinal cells, in 83.8%, Anoplocephala perfoliata in 16.2%, Eimeria leuckarti in 64.9%, Giardia in 5.4%, Cryptosporidium parvum in 2.7% and Gasterophilus intestinalis in 21.6%. Parasitic infections with two or more species were found in 83.8% of the foals. The species spectrum of endoparasites in mares from breeding farms without anthelmintic prophylaxis consisted of at least three species of small strongyles, whose third stage larvae were characterized by eight, 12 or 16 intestinal cells. In mares from breeding farms practising regular anthelmintic prophylaxis, however, at least seven species were ascertained, the same small strongyles, P. equorum, A. perfoliata, E. leuckarti and G. intestinalis.


Asunto(s)
Antihelmínticos/uso terapéutico , Helmintiasis Animal , Helmintos/aislamiento & purificación , Enfermedades de los Caballos/epidemiología , Envejecimiento , Crianza de Animales Domésticos , Animales , Femenino , Alemania/epidemiología , Helmintiasis/epidemiología , Helmintiasis/prevención & control , Caballos , Incidencia , Masculino , Especificidad de la Especie
17.
Z Parasitenkd ; 71(2): 227-40, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3993185

RESUMEN

Ultrastructure of daughter sporocysts and cercariae of Schistosoma japonicum were studied 2 and 4 months after infection of Oncomelania hupensis hupensis. The body walls of daughter sporocysts are similar at all infectious stages. They consist of an external syncytial tegument on a basement membrane, and an internal cellular subtegument surrounding a body cavity containing developing cercariae. The cercariae embryos develop 2 months after infection from germinal balls in the brood chamber of the daughter sporocyst. They are at first enveloped by a primitive epithelium rising from the daughter sporocyst. Four months after infection, the cercariae were almost fully developed and the primitive epithelium had degenerated. The body wall of the cercaria consists of a thin tegument covered by a surface coat of fibrous material and connected to the subtegumental cells by cytoplasmic processes. The matrix of the tegument contains numerous dense bodies, vacuoles, and spines. Two types of sensory structures - uniciliated and multiciliated - are found at the anterior tip of the cercaria. There are five pairs of penetration gland cells of two distinct types differentiated by the morphology of secretory granules. Flame cells are found in both daughter sporocysts and in cercariae. The cilia of the flame cells are characterized by the typical 9 and 2 cilium pattern.


Asunto(s)
Schistosoma japonicum/ultraestructura , Caracoles/parasitología , Animales , Larva/ultraestructura , Microscopía Electrónica , Schistosoma japonicum/crecimiento & desarrollo
18.
Zentralbl Bakteriol Orig A ; 241(3): 368-83, 1978 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-103340

RESUMEN

Six young pigs were experimentally infected with 100000 sporocysts of Sarcocystis suicanis and killed on the 32nd, 47th, 55th, 64th, 81th and 90th day p.i. The ultrastructure of sarcocysts in the muscle cells was studied. Light microscopical preliminary examination on the 32nd day p.i. showed cysts which lay in muscle fibres and were surrounded by a fine membran. On the 55th day p.i. the cyst wall showed radial light and dark stripes of 2.6 micrometer thickness, which reached a thickness of 3.2 micrometer on the 90th day p.i. The electron microscopic study of the cyst wall on the 32nd day p.i. showed a unit membran the numerous small outward projections of which are underlined by osmiophilic material that is absent in the inwardly directed invaginations. During the growth of the cyst, this primary cyst wall became regularly folded, forming many protrusions on the 55th day p.i. These appeared palisade-like and contained 57--62 filamentous elements in a single layer under the primary wall at a distance of 10 nm. In the centre of the protrusions there were 5--8 groups, comprising 2--5 filaments each. They have their origin in the ground-substance. As these filaments maintain their arrangement also in old cysts, they can be regarded as characteristic of Sarcocystis suicanis. The groundsubstance is homogenous; on the 32nd day p.i. it contained only metrocytes, and developed septa towards the interior of the cyst on the 47th day p.i. The parasites were reproduced by endodyogeny and appeared very similar to the structure of all cyst forming coccidians. Some old cysts degenerated fattily and the host cells were destroyed. The cysts of Sarcocystis suicanis with complete development of the protrusions of the primary wall can thus be differentiated from cysts of Sarcocystis suihominis with certainty.


Asunto(s)
Músculos/parasitología , Sarcocystis/crecimiento & desarrollo , Sarcocistosis/parasitología , Animales , Perros , Sarcocystis/ultraestructura , Especificidad de la Especie , Porcinos
19.
Z Parasitenkd ; 49(2): 97-112, 1976 Apr 30.
Artículo en Alemán | MEDLINE | ID: mdl-1274388

RESUMEN

The fine structure of trophozoites and especially of merozoites of Babesia herpailuri is described before and after treatment with Imidocarb (Wellcome). The mostly piriform to oval merozoites possess an outer membrane and a supporting membrane below. The intratorium consists of a polar ring, rhoptries micronemes and the sperical body which lies beside the big nucleus and next to mitochondria. The endoplasmic reticulum and invaginations are not clearly formed. The cellular changes of Babesia herpailuri, observed one hour after drug treatment in trophozoites and six hours later in merozoites, concern the form and function of the parasite: widening of the subpellicular endoplasmic reticulum and of the perinuclear space; sporadic dilatation of the endoplasmic reticulum of the merozoites (9 fig.). Damaged membranes, dissolution of the cellular membrane, disintegration of the nuclei as are known effects of the Berenil treatment to Babesia herpailuri, are not noted results after the Imidocarb treatment. The original membrane systems of trophozoites as well as of merozoites, remain unaffected by the drug as long as investigations were carried on (24 h). The satisfying prophylactic effect of Imidocarb as well as the insignificant cellular damages on merozoites may be due to the small feeding of hemoglobin.


Asunto(s)
Babesia/efectos de los fármacos , Carbanilidas/farmacología , Imidocarbo/farmacología , Animales , Babesia/ultraestructura , Gatos , Eritrocitos/parasitología , Masculino
20.
Z Naturforsch C Biosci ; 31(11-12): 687-92, 1976.
Artículo en Alemán | MEDLINE | ID: mdl-138287

RESUMEN

Euglena gracilis Klebs (strain Z) was grown heterotrophically in the dark for 6 days. Subsequently, the cells were grown photoautotrophically under white fluorescent light with varying amounts of 3-(3,4-dichlorophenyl)-1,1 dimethyl urea (DCMU) (1.7X10(-9)--1.0X10(-5)mol/l) added to the nutrient medium. Under non-photosynthetic conditions (addition of 10(-6)--10(-5)mol DCMU/l), the cells still produced chloroplast structures and a considerable percentage of compounds typical for chloroplasts, such as galactolipids (40-50%), chlorophylls (40%), and polyunsaturated C16 and C18 fatty acids (16:2, 16:3, 16:4, 18:2, 18:3) (65%). The results indicate that under these conditions the above compounds are synthesized from carbon sources outside the chloroplasts.


Asunto(s)
Diurona/farmacología , Euglena gracilis/metabolismo , Ácidos Grasos/metabolismo , Metabolismo de los Lípidos , Animales , Cloroplastos/efectos de los fármacos , Cloroplastos/metabolismo , Euglena gracilis/efectos de los fármacos , Euglena gracilis/ultraestructura , Glucolípidos/metabolismo , Cinética , Fotosíntesis/efectos de los fármacos
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