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1.
Comparative genomic hybridization (CGH) was used to detect copy number changes of DNA sequences in the Ewing family of tumours (ET). We analysed 20 samples from 17 patients. Fifteen tumours (75%) showed copy number changes. Gains of DNA sequences were much more frequent than losses, the majority of the gains affecting whole chromosomes or whole chromosome arms. Recurrent findings included copy number increases for chromosomes 8 (seven out of 20 samples; 35%), 1q (five samples; 25%) and 12 (five samples; 25%). The minimal common regions of these gains were the whole chromosomes 8 and 12, and 1q21-22. High-level amplifications affected 8q13-24, 1q and 1q21-22, each once. Southern blot analysis of the specimen with high-level amplification at 1q21-22 showed an amplification of FLG and SPRR3, both mapped to this region. All cases with a gain of chromosome 12 simultaneously showed a gain of chromosome 8. Comparison of CGH findings with cytogenetic analysis of the same tumours and previous cytogenetic reports of ET showed, in general, concordant results. In conclusion, our findings confirm that secondary changes, which may have prognostic significance in ET, are trisomy 8, trisomy 12 and a gain of DNA sequences in 1q.  相似文献   
2.
Although simple geometrical shapes are commonly used to describe tree crowns, computational geometry enables calculation of the individual crown properties directly from airborne lidar point clouds. Our objective was to calculate crown volumes (CVs) using this technique and validate the results by comparing them with field-measured values and modelled ellipsoidal crowns. The CVs of standing trees were obtained by measuring the crown radii at different heights, integrating the obtained crown profiles as solids of revolution, and finally averaging the volumes obtained from the four separate profiles. With the lidar data, the CVs were extracted using 3D alpha shape and 3D convex hull techniques. Crown base heights (CBHs) were also estimated from the lidar data and used to exclude echoes from the understory, which was also done using field-based CBHs to exclude this error source. The results show that the field-measured CVs had a high correlation with lidar-based estimates (best R 2 = 0.83), but the lidar-based estimates were generally smaller than the field values. The best correspondence (root mean square difference (RMSD) = 45.0%, average difference = –24.7%) was obtained using the convex hull of the point data and field-measured CBH. The CBHs were consistently overestimated (RMSD = 37.3%; average difference = –20.0%), especially in spruces with long crowns. Thus using lidar-based CBH also increased the inaccuracy of the CV estimates. While the underestimation of CV is mainly explained by the inadequate number of echoes from the lower regions of the crowns, the CVs obtained from the lidar were better than those obtained with ellipsoids fitted by using general models for crown dimensions. The utility of the estimated CVs in the prediction of stem diameter is also demonstrated.  相似文献   
3.
A significant correlation (r = -0.48) was found between the logarithm of the S-phase fraction of the primary tumour (SPF) and the logarithm of the doubling time of lung metastases (T2). The estimated median cell loss factor was 88% (range 35-99%).  相似文献   
4.
Middle-ear ventilation tubes (of the Sheehy modification) were placed in 401 ears of 209 children under 16 years of age as treatment for recurrent middle-ear infection. The same procedure was later required in 26% of the cases studied because of further recurrence of middle-ear infection. In four per cent of all patients studied, the ventilating tube failed to cure middle ear disease in spite of controlled concomitant antibacterial therapy. In these cases, an early extrusion of the tube was commonly found. Among all patients, the tube was spontaneously extruded in 76 per cent of the ears, whereas the intubation time was longer than half a year in 53 per cent of the cases. No complications from insertion of the ventilation tubes was seen in the present series of patients. The tympanic membrane was found to be normal in 71 per cent of all cases when follow-up examination was obtained three months after completion in intubation. However, a permanent tympanic membrane perforation was found in five ears (1% of patients). The present study has confirmed the usefulness of middle-ear ventilation tubes, particularly in patients with recurrent middle-ear infections.  相似文献   
5.
The adhesion between aqueous-based hydroxypropyl methylcellulose (HPMC) films and tablet surface was evaluated using a Lloyd LRX materials testing machine. Special attention was paid to the effects of compression pressure and the excipients (microcrystalline cellulose, lactose and a commercial combination of lactose and cellulose (CellactoseR)) on the adhesion properties of the film.

The adhesion of HPMC films was the lowest for the tablets containing lactose as a diluent and the highest for the tablets containing microcrystalline cellulose. The adhesion to CellactoseR-based tablets increased with increasing compression pressure. With microcrystalline cellulose (MCC) and lactose, the effect of compression pressure on film adhesion was not so clear. The increase in concentration of a hydrophopic lubricant, magnesium stearate, decreased the adhesion between the films and tablets cores. The greatest decrease was observed with the MCC tablets.

Furthermore the results showed that, the film coating increased clearly the mechanical strength of the tablets, depending on the excipient, the compression pressure and amount of magnesium stearate.  相似文献   
6.
An analytical method has been developed for evaluating the unreliability of complex systems with repair when redundancy is active. Failures of components are assumed to follow the Poisson process and to be independent of each other. The calculation algorithms of the method can be used in practice for approximations of fault tree. A numerical comparison of the method with the Markov process and a complete example of a fault tree evaluation are presented.  相似文献   
7.
Attempts to determine whether the quality of schizophrenic thought disorder varies from one type of schizophrenic to another in earlier studies have been hindered by the contamination of the major individual difference dimensions with each other. In the project described here, partial correlations were run between each of two abstraction deficit measures (Proverbs Test Abstract Level and Autism scores) and four independent variables which represent dimensions commonly used as criteria in individual differences research in schizophrenia--Ullmann-Giovannoni Process-Reactive scores, the MMPI Paranoia Scale, length of illness, and length of hospitalization. In each correlation the three noncriterion individual difference measures, the unused abstraction measure, age, education, and WAIS Vocabulary were partialed out. The correlations were also corrected for attenuation. After partialing, level of abstraction was negatively correlated with processness. Autism was positively related to reactiveness and length of hospitalization. Neither of two paranoid/nonparanoid measures used nor length of illness was related to either dependent variable.  相似文献   
8.
We present a simple and rapid method for screening nisin producers that directly identifies nisinogenic bacteria by induction of bioluminescence within the Lactococcus lactis NZ9800lux biosensor strain (Immonen and Karp, 2007, Biosensors and Bioelectronics 22, 1982-7). An overlay of putative nisinogenic colonies with the biosensor strain gives identification results within 1h. Functionality and specificity of the method were verified by screening nisin producers among 144 raw milk colonies and a panel of 91 lactococcal strains. Studies performed on strains and colonies that did not induce bioluminescence but inhibited growth of the biosensor demonstrated that only nisinogenic bacteria can cause induction. Bacteria known to produce bacteriocins other than nisin failed to induce bioluminescence, further verifying the specificity of the assay. We discovered a non-inducing but inhibitory lactococcal strain harboring a modified nisin Z gene, and demonstrated that the source of the inhibitory action is not a non-inducing variant of nisin, but a bacteriocin of lower molecular weight. The concentration of nisin producers in a raw milk sample was 1.3×10(2)CFU/ml. We identified from raw milk a total of seven nisin Z producing L. lactis subsp. lactis colonies, which were shown by genetic fingerprinting to belong to three different groups. Among the panel of 91 lactococci, four strains were nisin A producers, and one strain harbored the modified nisin Z gene. The method presented here is robust, cost-effective and simple to perform, and avoids the pitfalls of traditional screening methods by directly specifying the identity of the inhibitory substance.  相似文献   
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