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1.
Lipofilling (LF) is a largely employed technique in reconstructive and esthetic breast surgery. Over the years, it has demonstrated to be extremely useful for treatment of soft tissue defects after demolitive or conservative breast cancer surgery and different procedures have been developed to improve the survival of transplanted fat graft. The regenerative potential of LF is attributed to the multipotent stem cells found in large quantity in adipose tissue. However, a growing body of pre-clinical evidence shows that adipocytes and adipose-derived stromal cells may have pro-tumorigenic potential. Despite no clear indication from clinical studies has demonstrated an increased risk of cancer recurrence upon LF, these observations challenge the oncologic safety of the procedure. This review aims to provide an updated overview of both the clinical and the pre-clinical indications to the suitability and safety of LF in breast oncological surgery. Cellular and molecular players in the crosstalk between adipose tissue and cancer are described, and heterogeneous contradictory results are discussed, highlighting that important issues still remain to be solved to get a clear understanding of LF safety in breast cancer patients.  相似文献   
2.
International Journal of Control, Automation and Systems - In the framework of the Future Internet, the aim of the Quality of Experience (QoE) Control functionalities is to track the personalized...  相似文献   
3.
The rank of a matrix can be expressed as the least number of sums of direct products into which the matrix can be decomposed. Some applications to nets of linear threshold elements are given.  相似文献   
4.
The paper reports an investigation on a continuous model for dynamics of large-diameter sagged cables, taking bending stiffness and sag extensibility into account. Following the classical guidelines of cable dynamics, and by making some simplifications, a continuous model is found in this work; frequency and mode shape equations have been obtained in non-dimensional form. Comparison with Finite Element (FE) and Finite Difference (FD) models has been made to validate the proposed method. Moreover, it allows us to represent local effects at the end zones of cable correctly, if clamped boundary conditions are assumed. To obtain comparable results, the FE model would require a large subdivision, with consequently, a large number of elements. The proposed eigenfunctions allow us to solve the dynamic problem without a large computational effort compared to FE or FD approaches. Finally, in order to show the usefulness of the developed continuous model, an application on the main cables of the designed Messina Strait Bridge has been made.  相似文献   
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6.
This paper addresses the dynamic analysis of linear systems with uncertain parameters subjected to deterministic excitation. The conventional methods dealing with stochastic structures are based on series expansion of stochastic quantities with respect to uncertain parameters, by means of either Taylor expansion, perturbation technique or Neumann expansion and evaluate the first- and second-order moments of the response by solving deterministic equations. Unfortunately, these methods lead to significant error when the coefficients of variation of uncertainties are relatively large. Herein, an improved first-order perturbation approach is proposed, which considers the stochastic quantities as the sum of their mean and deviation. Comparisons with conventional second-order perturbation approach and Monte Carlo simulations illustrate the efficiency of the proposed method. Applications are discussed in order to investigate the influence of mass, damping and stiffness uncertainty on the dynamic response of the system.  相似文献   
7.
The aim of this paper is to describe and discuss, on the basis of the available literature, the case of an old female patient, admitted to our university hospital because of a severe dysphagia for solid foods, in whom laboratory data showed a marked hypomagnesemia. She reported a long history (20 years) of allergic bronchial asthma treated with theophylline. Esophagography evidenced a disorder of esophagus motility with diffuse multiple spasm, reminiscent of the 'corkscrew esophagus'. A link with the severe hypomagnesemia (Mg 1.1 mEq/l, normal range 1.6-2.1) was suspected, and a therapy with oral pidolate of Mg (1.5 g/twice a day) was started and continued for 4 months. This was associated with a slow progressive normalization of the Mg plasma level and reverted radiographic esophageal findings with disappearance of dysphagia. Mg is an important element for health and disease, and today Mg deficiency in man has become an accepted medical problem which might complicate many diseases. Neuromuscular disorders, as laryngeal spasm, are recognized complications of hypomagnesemia, but until now only 1 case of motor esophageal disorder associated with a low Mg plasma level was briefly reported in the literature, even if dysphagia is generally included in the symptomatological pattern of hypomagnesemia. Our observation of a severe form of esophageal spasm, associated with hypomagnesemia, in an aged female patient underlines the pathophysiological meaning of the plasma Mg level and suggests the need for routine Mg determination in the clinical setting.  相似文献   
8.
Network survivability requires the provisioning of backup resources in order to protect active traffic against any failure scenario. Backup resources, however, can remain unused most of the time while the network is not in failure condition, inducing high power consumption wastage, if fully powered on. In this paper, we highlight the power consumption wastage of the additional resources for survivability in IP/multi-protocol label switching (MPLS) over dense wavelength division multiplexing multi-layer optical networks. We assume MPLS protection switching as the failure recovery mechanism in the network, a solution interesting for current network operators to ensure fast recovery as well as fine-grained recovery treatment per label switched path. Next, we quantitatively show how elastic optical technologies can effectively reduce such a power consumption by dynamically adjusting the data rate of the transponders to the carried amount of traffic.  相似文献   
9.
Recently, spinal cord stimulation (SCS) has been used for the treatment of patients in prolonged coma. However, the results of SCS in unresponsive patients with hypoxic encephalopathy at the chronic stage have not been satisfactory. Considering these circumstances, we began SCS from one month after the onset of hypoxic encephalopathy and evaluated its effect. Twelve patients (5 males and 7 females) with hypoxic encephalopathy, ranging in age from 7 to 72 years, were treated with SCS. The causes of hypoxia were acute cardiac failure in 4, automobile exhaust gas poisoning in 2, and asthma, pneumothorax, anaphylaxis, asphyxia, drowning and hypotension during aortic surgery in one patient each. One month after the onset, an electrode for electrical stimulation was implanted in the epidural space at the C2-C4 level under general anesthesia. The spinal cord was stimulated for 8 hours each day, starting on the day after implantation, and was continued for 3 months. Magnetic resonance imaging (MRI), cerebral blood flow (CBF) measurement using xenon-computed tomography (Xe-CT), and measurement of auditory evoked potential (AEP) and somatosensory evoked potential (SEP) were carried out 3 weeks after the onset for presurgical evaluation. Among the 12 patients, 7 (58%) showed clinical improvement, beginning within two weeks after starting stimulation. They were able to communicate with others and to express their emotion. However, disturbance of writing, picture drawing and calculation were not improved by stimulation. From presurgical evaluation, cases in which SCS therapy was effective had the following features: 1) No hemorrhagic infarction in the basal ganglia was demonstrable by MRI. 2) Mean hemispheric CBF measured by the Xe-CT method exceeded 25 ml/100 g per min. 3) The mean increase in hemispheric CBF 20 min after acetazolamide administration exceeded 5 ml/100 g per min. 4) An N20 peak was evident on the median nerve SEP, SCS appears to be an effective supplementary for unresponsive patients with hypoxic encephalopathy at the subacute stage, in addition to rehabilitation and drug therapy.  相似文献   
10.
In this paper we will consider an overview of the precious alloys that could be of interest due to the inherent properties of the thermoelastic martensitic transformation that they exhibit. For sure one of the main representatives of these materials can be considered the AuAlCu system (and the related well known SpangoldTM). Actually in the literature, since the late '70s, other systems have been indicated of interest but they knew a very limited success. We refer here to some pioneering work from G.B. Brook In more recent time the increasing experience in the science and technology of conventional shape memory alloys like NiTi (which in the meantime successfully reached the application field) brought a new interest for a clear understanding of the potential of these gold alloys. Here we report on results obtained in the three areas: spangold-like alloys, AuCuZn alloys, and a ternary modification of NiTi, i.e. NiTiAu. The samples used for the investigation have been prepared starting from pure metals and thoroughly investigated by means on differential scanning calorimetry, X-ray diffraction at different temperatures and optical microscopy. When possible the samples were submitted to simple recovery test to verify the amount of shape memory and/or pseudoelastic properties.  相似文献   
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