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51.
Nine white-rot fungal strains were screened for biodecolourization of brilliant green, cresol red, crystal violet, congo red and orange II. Dichomitus squalens, Phlebia fascicularia and P. floridensis decolourized all of the dyes on solid agar medium and possessed better decolourization ability than Phanerochaete chrysosporium when tested in nitrogen-limited broth medium. Journal of Industrial Microbiology & Biotechnology (2002) 28, 201–203 DOI: 10.1038/sj/jim/7000222 Received 12 July 2001/ Accepted in revised form 22 October 2001  相似文献   
52.
Membranes in the mitotic apparatus have been investigated ultrastructually in dividing cells of barley (Hordeum vulgare). After osmium tetroxide- potassium ferricyanide or ferrocyanide postfixation (OsFeCN) of material that had been fixed in glutaraldehyde in the presence of Ca(++), the nuclear envolope (NE)-endoplasmic reticulum (ER) complex is selectively stained, permitting observations on the cellular pattern and structural ramifications of this membrane system that have not been previously recognized. Specifically, it is observed that membrane system that have not been previously recognized. Specifically, it is observed that during mitosis the NE-ER forms a continuous membrane system that ensheathes and isolates the mitotic apparatus (MA). Elements of ER progressively accumulate in the region of the spindle pole, becoming most concentrated by early anaphase. Within the MA itself, there are striking spindle- membrane associations; in particular, tubular elements of predominantly smooth NE-ER invade the spindle interior selectively along kinetochore microtubules. The membrane elements at the pole and surrounding the MA consist of tubular reticulum and fenestrated lamellae. Membranes of the MA thus resemble in considerable detail the tubular network and fenestrated elements of the sarcoplasmic reticulum of muscle. It is suggested that the NE-ER of the dividing barley cell may function in one or both of the following ways: (a) to control the concentration of free Ca(++) in the MA and (b) to serve as an anchor to chromosome motion.  相似文献   
53.
Recombinant modified vaccinia virus Ankara (MVA), encoding the measles virus (MV) fusion (F) and hemagglutinin (H) (MVA-FH) glycoproteins, was evaluated in an MV vaccination-challenge model with macaques. Animals were vaccinated twice in the absence or presence of passively transferred MV-neutralizing macaque antibodies and challenged 1 year later intratracheally with wild-type MV. After the second vaccination with MVA-FH, all the animals developed MV-neutralizing antibodies and MV-specific T-cell responses. Although MVA-FH was slightly less effective in inducing MV-neutralizing antibodies in the absence of passively transferred antibodies than the currently used live attenuated vaccine, it proved to be more effective in the presence of such antibodies. All vaccinated animals were effectively protected from the challenge infection. These data suggest that MVA-FH should be further tested as an alternative to the current vaccine for infants with maternally acquired MV-neutralizing antibodies and for adults with waning vaccine-induced immunity.  相似文献   
54.
Breast cancer is one of the top three commonly caused cancers worldwide. Triple Negative Breast Cancer (TNBC), a subtype of breast cancer, lacks expression of the oestrogen receptor, progesterone receptor, and HER2. This makes the prognosis poor and early detection hard. Therefore, AI based neural models such as Binary Logistic Regression, Multi-Layer Perceptron and Radial Basis Functions were used for differential diagnosis of normal samples and TNBC samples collected from signal intensity data of microarray experiment. Genes that were significantly upregulated in TNBC were compared with healthy controls. The MLP model classified TNBC and normal cells with anaccuracy of 93.4%. However, RBF gave 74% accuracy and binary Logistic Regression model showed an accuracy of 90.0% in identifying TNBC cases.  相似文献   
55.
A study of the mode of formation of coremia in three species ofTrichurus Clem. et Shear showed that this process is identical to that in the genusDoratomyces Cda. A discussion of the importance of setae in the classification of imperfect fungi indicates that the separation of the generaTrichurus andDoratomyces may not be a natural one.  相似文献   
56.
An electrophoretic karyotype of Aspergillus niger   总被引:4,自引:0,他引:4  
Summary An electrophoretic karyotype of Aspergillus niger was obtained using contour-clamped homogeneous electric field (CHEF) gel electrophoresis. Chromosomesized DNA was separated into four bands. Seven of the eight linkage groups could be correlated with specific chromosomal bands. For this purpose DNA preparations from seven transformant strains of A. niger each carrying the heterologous amdS gene of Aspergillus nidulans on a different chromosome were analysed. Some of the assignments were confirmed with linkage groupspecific A. niger probes. The estimated sizes of the A. niger chromosome range from 3.5 to 6.6 Mb, based on gel migration relative to the chromosomes of Schizosaccharomyces pombe strains, Saccharomyces cerevisiae and A. nidulans. The total genome size of A. niger significantly exceeds that of A. nidulans and is estimated to be about 35.5–38.5 Mb. Electrophoretic karyotyping was used to allocate non-mutant rRNA genes and to estimate the number of plasmids integrated in a high copy number transformant.  相似文献   
57.
Evidence is presented that a compartmentalised protein exists in its native state only within a particular size of aqueous cavity. This behaviour is shown to exist in AOT reverse micelles using fluorescence quenching and circular dichroism (CD) studies of human serum albumin (HSA). In particular, far ultraviolet CD measurements show that a reduction in quencher accessibility to the fluorophore is consistent with the protein being nearest to its native conformation at a waterpool size of around 80 Å diameter. We also show that the biexponential fluorescence decay of N-acetyl-l-tryptophanamide (NATA) in AOT reverse micelles arises from the probe being located in two distinct sites within the interfacial region. The more viscous of these two sites is located on the waterpool side of the interface and the other is located on the oil side of the interface.  相似文献   
58.
The most recent IPCC report presented further scientific evidence for global climate change in the twenty-first century. Important secondary effects of climate change include those on water resource availability, agricultural yields, urban healthy living, biodiversity, ecosystems, food security, and public health. The aim of this explorative study was to determine the range of expected airborne pathogen concentrations during a single outbreak or release in a future climate compared to a historical climatic period (1981–2010). We used five climate scenarios for the periods 2016–2045 and 2036–2065 defined by the Royal Netherlands Meteorological Institute and two conversion tools to create hourly future meteorological data sets. We modelled season-averaged airborne pathogen concentrations by means of an atmospheric dispersion model and compared these data to historical (1981–2010) modelled concentrations. Our results showed that modelled concentrations were modified several percentage points on average as a result of climate change. On average, concentrations were reduced in four out of five scenarios. Wind speed and global radiation were of critical importance, which determine horizontal and vertical dilution. Modelled concentrations decreased on average, but large positive and negative hourly averaged effects were calculated (from ?67 to +639 %). This explorative study shows that further research should include pathogen inactivation and more detailed probability functions on precipitation, snow, and large-scale circulation.  相似文献   
59.
X-radiography and carbon and oxygen stable isotope analysis have been used to examine the effects of prolonged bleaching on the growth rate and chemical composition of the skeleton of the massive reef coral, Montastrea annularis. The post-bleaching linear growth of one colony that remained bleached for 10 to 12 months following the 1987 Caribbean-wide bleaching event was only 37% of mean annual growth from pre-bleaching years, and was manifest as a loss of the following year's low density band. Two colonies that did not bleach (normal) and two that bleached and regained their coloration (recovered) had linear growth rates over the same period that were 81 to 98% of mean pre-bleaching annual growth. Linear growth by a third recovered coral was 66% of pre-bleaching growth. No sub-annual stress bands were associated with the bleaching. The skeleton of the bleached colony had carbon and oxygen isotopic compositions that were reduced in range and enriched (increased) in both 13C and 18O in the post-bleaching year. The skeletons of two of the nine colonies, one bleached and one recovered, had depleted (reduced) 18O values (-5.3 and -4.8%., respectively) during the bleaching episode that agree with the suggestion that positive temperature anomalies occurred during, and may have caused, the bleaching event. The range and values for all other normal and recovered corals, however, were not different between the post-bleaching year and previous years. Our data suggest that stress bands and isotopic analysis of coral skeletons may not always be reliable tools for examining the occurrence, cause or effects of certain discrete stress events that may interrupt skeletal growth.  相似文献   
60.
The principle of a multiple wavelength illumination method for flow cytometers, based upon a combination of a helium-neon laser and an arc lamp as illumination sources is described. By using a prism, the light from the arc lamp is dispersed and the different colors are imaged at different places on the sample stream. The small angle light scattering from the helium-neon laser light is measured as a relevant parameter and serves as a trigger signal for subsequent measurements of fluorescence or scattering of light from the arc lamp. Two experimental systems are described utilizing this principle: a system where the emission is detected orthogonally with respect to the direction of the illumination beams, and an epi-illumination system. With the orthogonal set-up multiple wave-length right angle scattering measurements are possible. This is illustrated by showing that the orthogonal scattering from erythrocytes is strongly dependent on the illumination wavelength. It is further shown that the apparatus is suitable for the measurement of intracellular pH using the pH dependence of the excitation spectrum of fluorescein. The epi-illumination system allows excitation of two (or more) fluorescent dyes with different excitation spectra. In this case the emission spectra of the fluorescent dyes may overlap substantially. This is shown by simultaneous measurement of DNA and protein of Chinese hamster lung cells using mitramycin and tetramethyl rhodamin isothiocyanate (TRITC).  相似文献   
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