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51.
The aim of the study was to determine how those texture attributes that elderly people find difficult to eat are related to their preferences for different modifications of carrot textures. This study was conducted with same methods in Finland and in the United Kingdom (UK). Trained sensory panels in both countries described sensory profiles of a range of carrot samples with same glossary of texture terms. The texture of carrot samples was manipulated using different preparation and cooking methods. Based on the Principal Component Analysis (PCA), boiled and puréed samples were perceived as soft, wet, pulpy and smooth, whereas raw samples were dry, brittle, rough, crispy and crunchy. Two age groups were used for the consumer tests: a young adult group aged 23 to 40 years, mean 32 (Finland) and 33 (UK) and an elderly group aged over 60 years, mean 75 (Finland) and 76 (UK). Both the elderly and young adult respondents considered samples as difficult to eat if they needed a long chewing time, were crunchy, hard, brittle, dry, rough or sharp, such as raw slices and coarsely grated samples. On the other hand, slimy, wet, smooth, soft and pulpy samples, such as boiled carrots and purée, were considered as easy-to-eat. The young adults liked more difficult textures such as rough, crispy, crunchy and hard than did the elderly respondents, but the easiest textures were not liked by either age group. Subjects with dental deficiencies liked easier textures more than those fully dentate.  相似文献   
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The motion of a nonquasineutral plasma in a strong magnetic field such that is analyzed. It is shown in simple examples that, when the plasma pressure and dissipation are neglected, the only dynamic process in a magnetized plasma is the evolution of the charge-separation electric field and the related magnetic field flux. The equations derived to describe this evolution are essentially the wave Grad-Shafranov equations. The solution to these equations implies that, in a turbulent Z-pinch, a steady state can exist in which the current at a supercritical level is concentrated near the pinch axis.  相似文献   
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Purpose of the investigation was to compare physiological reactions of primates (Macaca mulatta) to microgravity simulated by immersion and head-down tilt (HDT). In immersion experiments, primates in waterproof suits were put into motion-restraining chairs and immersed into water (t=35.4 degrees C) breast-deep for 9 days. In 9-d HDT experiments, prone primates were motor restrained in dedicated tilt beds at -5 degrees. It was found that the CNS functioning was significantly affected, the plasma volume reduced and the marrow erythropoietic function declined. Atrophy developed in leg muscles on a backdrop of iliopectineal spongy osteopenia. Loss in hydration, inhibition of erythropoietic hemopoiesis and iliopectineal spongy osteopenia were more pronounced following immersion than HDT.  相似文献   
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Abstract. The division rate of Micrasterias torreyi cells grown under continuous illumination first accelerated but soon slowed down, and the cells lost their ability to divide after about 1 month. During the treatment the cells became pale green, the pyrenoids became fewer in number and defects appeared in the chloroplasts. After 1 month, the cells also soon died, even when subjected to intermittent illumination. The most striking structural alterations were found in the chloroplasts: the starch granules lost their typical structure, the lamellae were damaged and numerous electron dense precipitates appeared in the chloroplasts. The precipitates were similar to those formed in cells treated with supraoptimal external calcium concentrations and X-ray microanalysis showed that the precipitates were rich in calcium in both cases. The results suggest that light controls and activates the Ca2+ uptake in the plasma membrane as well as in the chloroplast envelope, that the large sized chloroplasts of Micrasterias are effective in regulation of cytoplasmic Ca2+ concentration, and that the injuries caused by continuous illumination may be largely due to the accumulation of Ca2+ in the chloroplasts.  相似文献   
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84 patients with panic disorders and 36 healthy control subjects with use of clinico-neurologic technique, psychometric, neuropsychological and the neurophysiological method of auditory event-related potentials P300 were examined. Patients with panic disorders were characterized by the raised level of anxiety, depression and cognitive function disturbances in the form of decrease of short-term memory and attention insufficiency in comparison with the healthy control subjects. Patients with atypical panic disorders differed from the patients with typical panic disorders by lower level of anxiety, a greater degree of depression and more expressed cognitive function disturbances. In comparison with the healthy control subjects with atypical panic disorders the decrease of P300 peak amplitude was observed, with typical--its augmentation. It is supposed, that P300 peak change is bound to dysfunction of temporal-limbic-reticular brain structures.  相似文献   
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Settlements near the Semipalatinsk Test Site (SNTS) in northeastern Kazakhstan were exposed to radioactive fallout during 1949-1962. Thyroid disease prevalence among 2994 residents of eight villages was ascertained by ultrasound screening. Malignancy was determined by cytopathology. Individual thyroid doses from external and internal radiation sources were reconstructed from fallout deposition patterns, residential histories and diet, including childhood milk consumption. Point estimates of individual external and internal dose averaged 0.04 Gy (range 0-0.65) and 0.31 Gy (0-9.6), respectively, with a Pearson correlation coefficient of 0.46. Ultrasound-detected thyroid nodule prevalence was 18% and 39% among males and females, respectively. It was significantly and independently associated with both external and internal dose, the main study finding. The estimated relative biological effectiveness of internal compared to external radiation dose was 0.33, with 95% confidence bounds of 0.09-3.11. Prevalence of papillary cancer was 0.9% and was not significantly associated with radiation dose. In terms of excess relative risk per unit dose, our dose-response findings for nodule prevalence are comparable to those from populations exposed to medical X rays and to acute radiation from the Hiroshima and Nagasaki atomic bombings.  相似文献   
60.
A previously developed method for describing vortex structures is used to construct electrostatic vortices in a plasma in an external magnetic field. An equation for the radial electric field that gives rise to azimuthal electron drift in crossed electric (E r ) and magnetic (B z ) fields is derived without allowance for the magnetic field of the electron currents. Two types of the resulting electrostatic vortex structures with a positive and a negative electric potential at the axis are analyzed. The results obtained are compared with experimental data on vortex structures.  相似文献   
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