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1.
In this study we utilized bioelectrical impedance analysis (BIA) to compare the body composition of 36 stable pulmonary emphysema (PE) patients with 19 healthy controls. We compared the PE patients and healthy controls in terms of fat-free mass (FFM) and body fat (BF) as percentages of ideal body weight (FFM/IBW, BF/IBW). FFM/IBW and BF/IBW were significantly lower in the PE patients than in the controls (75.0 +/- 9.8% vs. 85.2 +/- 7.3%, p < 0.001 and 11.8 +/- 6.4% vs. 16.7 +/- 7.7%, p < 0.05, respectively). We divided the PE patients into two subgroups according to FFM, then investigated the relationships between FFM and skeletal muscle strength, and between FFM and respiratory muscle strength. In patients with reduced FFM (FFM < 43.5 kg) grip strength as an index of skeletal muscle strength was significantly lower than in patients without reduced FFM (FFM > or = 43.5 kg) (25.7 +/- 7.8 kg vs. 36.2 +/- 7.2 kg, p < 0.005). As indexes of respiratory muscle strength, maximal expiratory pressure (PEmax) and maximal inspiratory pressure (PImax) were lower in the patients with reduced of FFM, but not to a statistically significant degree (49.6 +/- 20.8 cm H2O vs. 58.7 +/- 23.9 cm H2O and 40.5 +/- 19.2 cm H2O vs. 50.2 +/- 22.1 cm H2O, respectively). In the PE patients, FFM correlated closely with vital capacity (r = 0.528, p < 0.001), forced vital capacity (FVC) (r = 0.531, p < 0.001), FEV1.0 (r = 0.554, p < 0.001), FEV1.0/FVC (r = 0.467, p < 0.005), RV/TLC (r = -0.395, p < 0.05), DLco (r = 0.770, p < 0.001), and DLco/VA (r = 0.622, p < 0.001). However no correlation was observed between BF and any of the measures of lung function. The findings of our study suggest that FFM correlates with skeletal muscle strength, respiratory muscle strength and some measures of lung function in patients with PE, and that assessments of body composition are valuable to their clinical management.  相似文献   
2.
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
3.
Ikuno  H. 《Electronics letters》1979,15(23):762-763
Corrected propagation of the guided modes in a graded-index fibre with a polynomial-profile core are given in analytic form by using a modified Maslov's formula. The result coincides with one obtained by the evanescent-field theory.  相似文献   
4.
Reflection from a smooth target with inflection points, when investigated by the physical optics method, reveals far-zone contributions arising from real and complex stationary points. The former represent conventional specularly reflected real-ray fields whereas the latter, which are nonspecular in real space, can be interpreted as complex-ray fields reflected specularly from the complex extension of the scatterer surface. To explain the nonspecular contributions, the complex stationary point fields are regarded as specular reflections of complex incident rays from the analytic extension of the boundary into a complex coordinate space. It is verified that this construction using complex geometrical optics is in complete agreement with physical optics asymptotics and that the complex reflection points for far-zone fields lie near the concave-to-convex transitions on the physical contour. Numerical results supporting the validity of this assertion are provided. It is concluded, therefore, that a complete ray theory of reflection from the illuminated portion of a smooth object with inflection points must include specularly reflected real as well as complex rays, with the latter originating from the complex extension of the surface contour  相似文献   
5.
As an approach to the broad-band, multi-port, multilateral media with idealized transmitting ability for various communications, a "Flat Loss Boosted Coaxial Line" (FLB Line) with many ports, such a centipede, has been proposed. It has been built from Negativeresistance BridgedTtypesqrt{f}shape Boosters (FBA) with about 10 dB gain at 300 MHz and Negative-resistance Boosting Junctions (NBJ) with an effective gain of 4.8 dB and no directivity nor phase distortion. In this line, signal powers at all branching ports axe principally equal and are transmitted bilaterally over all frequency range, while maintaining not only sufficient stability margin but also allowable transmission performance. A trial 2 km line composed of 8 FLB sections and 3 NBJ units has demonstrated engineering feasibility that bidirectional transmission of 5 color TV signals. It operated with almost no ghosts and without any adjacent channel interferences over a frequency range from 5 MHz up to about 400 MHz.  相似文献   
6.
7.
A method is introduced to calculate wedge factors for an enhanced dynamic wedge (EDW). An analytic formula has been derived that allows the determination of wedge factors at the center of symmetric and asymmetric photon fields. The formalism is an extension of the "MU fraction approximation," which holds that the dynamic wedge factor is equal to the fraction of MU delivered to the point of calculation. Extensive data are presented, comparing measured enhanced dynamic wedge factors with the current method and the MU fraction model for both symmetric and asymmetric fields. For both 6 and 18 MV photons, the current method demonstrates improved results: Agreement to within 1% is obtained in all symmetric fields and within 2% for all asymmetric fields compared with discrepancies of up to 4% obtained with the MU fraction model.  相似文献   
8.
Cutoff frequencies of the guided modes in a graded-index fibre with a finitely thick cladding are calculated by a refined WKB method. The results are in good agreement with the exact ones for the parabolic core fibre. The effect of the fourth order correction to the parabolic core fibre on the cutoff frequency is evaluated.  相似文献   
9.
The scattering problems for a nonconvex body can be analyzed by the physical-optics approximation. The method of stationary phase is a technique for evaluating the diffraction integral in the short-wavelength region. In case of the nonconvex body there exist several stationary points including the complex ones in the reduced phase integral. The radar cross section of the nonconvex body varies with frequency as a result of the interference of the scattered waves from each stationary point. For a moderately high frequency the solutions by the method of stationary phase agree with those obtained using the mode-matching method.  相似文献   
10.
Acoustic microscope can detect microstructural features with high resolving power compared to other lower frequency acoustic techniques. Many non-destructive evaluations using acoustic microscope, several of them used in industrial fields, were investigated. However, acoustic measurement of curved surface structure was restricted to basic studies as conventional acoustic microscope system was designed for flat specimen. We have developed a modified acoustic microscope for curved surface specimen testing and have measured acoustic image of round bar specimen. In this study, using this system, velocities of round bar specimen during fatigue test are monitored using the V(z) curve method. Measurement errors depending on curved surface measurement were investigated and it was found that the acoustic velocity tends to increase as fatigue damage increases.  相似文献   
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