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161.
Conclusiones Se efectúa el estudio de 5 observaciones del llamado Micetoma maduromicósico de pulmón en sus aspectos, histopatológico, micológico y clínico.Todas ellas pertenecen a mujeres y configuraron el cuadro de cavidad bronquial empastada, anotando el predominio de su localización en el lóbulo superior izquierdo.Se señala la uniformidad de los caracteres morfológicos que presenta la masa miceliana llamada grano en todos los casos estudiados, en los cuales no fué posible individualizar la existencia de órganos de fructificación que permitiéran una clasificación, cuando más no fuera, genérica del hongo observado.Se critica la aplicación del término Micetoma para éstos casos con igual criterio que el clásico, que supone una enfermedad micótica primitiva, razón por la cual se prefiere hablar de cavidad con contenido micótico o maduromicótico.En el único caso que se logró cultivar al hongo parásito, el estudio micológico del mismo permitió aislar una especie del GéneroAspergillua con caracteres morfológicos sumamente atípicos.
Summary The author presents the study of five observations of the so-called Maduromycosis-mycetoma of the lungs in their clinical, histopathologic and mycologic aspects.The pathologic features in all these cases have been found in bronchial cavities of women, situated in the upper lobe of the lung. A compact mycelial mass, the grain, filled up these cavities.In one of the five cases a fungus was cultivated which was classified as belonging to the GenusAspergillus Michelii, with abnormal and atypical features.Short criticism is presented about the concept Maduromycosis mycetoma of the lung, applied by authors designating this process.
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Reliable banding techniques are a major necessity for genetic research in oysters. In this study, we carried out the cytogenetic characterization of four oyster species (family Ostreidae) using restriction endonuclease treatments. Chromosomes were treated with three different restriction enzymes, stained with Giemsa, and examined for banding patterns. The following species were studied: Crassostrea gigas (2n = 20; total number of bands with ApaI, 74; HaeIII, 61; PstI, 76), Crassostrea angulata (2n = 20; ApaI, 62; HaeIII, 61; PstI, 55) (subfamily Crassostreinae), Ostrea edulis (2n = 20; ApaI, 82; HaeIII, 59; PstI, 66), and Ostrea conchaphila (2n = 20; ApaI, 68; HaeIII, 62; PstI, 69) (subfamily Ostreinae). Treatment of samples with ApaI, HaeIII, and PstI produced specific banding patterns, which demonstrates the potential of these enzymes for chromosome banding in oysters. This is of special interest, since it has been recently shown in mammalian chromosomes that restriction enzyme banding is compatible with fluorescence in situ hybridization. This study therefore provides a fundamental step in genome mapping of oysters, since chromosome banding with restriction enzymes facilitates physical gene mapping in these important aquaculture species. The analysis of the banded karyotypes revealed a greater similarity within the genera of Crassostrea and Ostrea than between them.  相似文献   
165.
Cytological smears from 115 consecutive cases of stereotactic biopsies of intracranial lesions were reviewed. Ninety-five lesions were solid and 20 cystic. Material from 90 solid and 13 cystic lesions was sent both for cytological and histological examination. In 66 of the solid lesions, the cytological diagnosis was confirmed by histology (five were benign lesions and 61 malignant tumours: 56 primary brain tumours, three metastases and two lymphomas). In 24 cases with discrepant cytology and histology, the histology was inconclusive or insufficient in 14 cases, while cytology established the diagnosis of astrocytoma grade II (seven cases), metastases (two cases), gliosis (one case) and benign (four cases). Necrosis of tumour type was observed cytologically in six patients representing glioblastoma (two cases), anaplastic astrocytoma (one case), lymphoma (one case) and normal brain (two cases) histologically. Three cases reported cytologically as benign were primary brain tumour (two cases) and gliosis (one case). One smear of a glioblastoma was insufficient for cytological diagnosis. Cystic lesions were cytologically benign in 17 cases and malignant in three cases. Histology from the cyst wall confirmed the malignant diagnosis in three cases and showed tumour in six more cases, a benign process (two cases), changes induced by radiotherapy for arteriovenous malformation (one case) and insufficient material (one case). In conclusion, cytology from solid brain lesion allows an accurate diagnosis and subtyping of tumours in a majority of cases, and can thus be used to choose type of therapy. In cystic brain tumours, however, examination of the cystic fluid, is often inconclusive and a biopsy from the cyst wall should be performed if there is clinical or radiological suspicion of tumour.  相似文献   
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Abstract: The influence of temperature on life table parameters of Podisus nigrispinus (Dallas) (Het., Pentatomidae) fed with Alabama argillacea (Hübner) (Lep., Noctuidae) larvae was studied. This predator was kept at constant temperatures of 20, 23, 25, 28, 30 and 33±0.2°C, at relative humidity of 60±10% and photoperiod of L : D 14 : 10. Gross (GRR) and net ( R 0) reproductive rates of P. nigrispinus ranged from 1.6 to 366.6 and from 0.02 to 189.5 females/female at temperatures of 33 and 28°C, respectively; generation time ( T  ) ranged from 33.3 (33°C) to 85.5 (20°C) days; doubling time ( D ) from 0.82 (33°C) to 17.8 (20°C) days; intrinsic rate of increase ( r m ) from −0.13 (33°C) to 0.12 (28°C) per day; and the finite rate of increase ( λ ) from 0.88 (33°C) to 1.12 (28°C) females/female added to the population per day. The ideal age to release P. nigrispinus should be when this predator presents higher reproductive values (VR x ); that is, its adults are about 7 days old, independent of prevailing temperature. Population growth of P. nigrispinus was affected by temperature with maximum numerical response between 28 and 30°C. The negative population growth shown at 33°C may not occur in natural conditions due to milder microclimate in the cotton agroecosystem and due to oscillations of temperature in the course of the day.  相似文献   
168.
Populations of two rhizomatous species, Asarum europaeum (asarabacca) and Maianthemum bifolium (May lily), were examined in two, and four forest habitats respectively, in the Roztocze National Park (south-eastern Poland). May lily populations were studied in habitats: the Carpathian beechwood, upland mixed fir forest, subboreal moist mixed coniferous forest and bog-alder forest. Asarabacca was studied in two habitats: beechwood and Scots pine community (an 80-year-old plantation). In both the species studied intra- and inter-populational differences of the size of genets in terms of above- and below-ground parts of individuals as well as the biomass and area occupied were observed. In May lily populations the greatest mean number of shoots per genet was found in the fir forest (11.62±3.29), a value almost twice as great as that in the moist coniferous forest and nearly three times greater than in the bog-alder forest. Total rhizome length was also the greatest in the fir forest (351.9±98.7 cm) followed by moist coniferous forest, beechwood and alder forest habitats. In all populations of May lily a greater part of total dry weight biomass is in below-ground organs. The greatest biomass value of a genet was found in the fir forest (4.275 g), the smallest in the bog-alder forest (0.110 g). All populations differed significantly in terms of leaf area, leaf length (with the exception of fir forest and beechwood habitats where the values were the greatest), and leaf width (excluding moist coniferous and bog-alder forests which had the smallest values). In the case of asarabacca, both the mean number of ramets per genet (3.36±0.45 vs. 2.49±0.20) and total rhizome length (40.3±6.4 cm vs. 21.1±1.8 cm) were greater in the beechwood habitat than in the pine community. In the first population genets had 3–5 times greater the total biomass of those from the pine community. Only genets of the latter had proportionately more dry weight biomass in above-ground parts. It seems to be correlated with greater rhizome dieback and disintegration of genets into smaller units. Both populations were significantly different in terms of all examined parameters of leaves. Genets of both the species studied were found to have their own structure of developmental phases that often differed for shoots and rhizomes.  相似文献   
169.
The marine microalga Phaeodactylum tricornutum was cultivated in semi-continuous culture under mixotrophic conditions with the soluble fractions of potato, rye and wheat flours that had been naturally fermented, at 2% or 4% (w/v). The rye flour produced the highest microalgal cellular density of 90×106 cells.ml-1 when supplemented with NaNO3 and NaH2PO4. The autotrophic control only gave 57×106 cells.ml-1. The value of agricultural surpluses, such as rye flour, can therefore be increased by its use in the production of valuable, microalgal biomass which is rich in protein, pigments and fatty acids.  相似文献   
170.
Glyptal, a polyester obtained from phthalic anhydride and glycerol, was used as a support for protein immobilisation. Hydrazide groups were introduced in the polymer and then converted to azide groups, through which protein was covalently immobilised. Amyloglucosidase was used as a model and an insoluble water derivative was synthesised retaining 24 % of the specific activity of the native enzyme. Some properties of this immobilised enzyme were studied: Km (4.54 g.l–1 using starch as substrate), optimal temperature (55°C) and half life (8 days). Furthermore, ferromagnetic-azide-glyptal derivative showed to be useful for the amyloglucosidase immobilisation.  相似文献   
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