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991.
Cytological investigations of the bronchial secretion and sputum in particular have acquired in recent years a great practical significance in pulmonary pathology. It is recommended to use cytodiagnosis along with prophylactic X-ray examinations of the population to detect pulmonary pathology, in particular among individuals with a higher risk of developing cancer. A substantiated opinion is put forward that cytodiagnosis should precede examinations of patients with clinico-roentgenologically confirmed changes in the lungs. 相似文献
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993.
Two cases of duodenal hematoma secondary to abdominal trauma in children are reported. The latent periods between trauma and the onset of symptoms were two and fifteen days. X-ray studies were conclusive for diagnosis. Pancreatic signs were mild in one case. Both cases were treated surgically, draining the fluid collection extramucosally. The authors advise surgical treatment whenever associated lesions need to be ruled out and when obstruction persists after the first days. 相似文献
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996.
André Maués Brabo Pereira Marcos Chataignier de Arruda Ant?nio Carlos de O. Miranda William Wagner M. Lira Luiz Fernando Martha 《Engineering with Computers》2012,28(3):225-239
An algorithm for Boolean operations on non-manifold models is proposed to allow the treatment of solids with multiple regions (internal interfaces) and degenerate portions (shells and wires), in the context of mesh generation. In a solid modeler, one of the most powerful tools to create three-dimensional objects with any level of geometric complexity is the Boolean set operators. They are intuitive and popular ways to combine solids, based on the operations applied to point sets. To assure that the resulting objects have the same dimension as the original objects, without loose or dangling parts, a regularization process is usually applied after a Boolean operation. In practice, the regularization is performed classifying the topological elements and removing internal or lower-dimensional structures. However, in many engineering applications, the adopted geometric model may contain idealized internal parts, as in the case of multi-region models, or lower-dimensional parts, as in the case of solids that contain dangling slabs that are represented as zero-thickness surfaces or wireframes in the model. Therefore, the aim of this work is the development of a generic algorithm that allows the application of the Boolean set operations in a geometric modeling environment applied to finite and boundary element mesh generation. This environment adopts a non-manifold boundary representation that considers an undefined number of topological entities (group concept), and works with objects of different dimensions and with objects not necessarily plane or polyhedral (parametric curved surfaces). Numerical examples are presented to illustrate the proposed methodology. 相似文献
997.
Reservoir Management Using Coupled Atmospheric and Hydrological Models: The Brazilian Semi-Arid Case
José Maria Brabo Alves José Nilson B. Campos Jacques Servain 《Water Resources Management》2012,26(5):1365-1385
This study investigated the sensitivity of a dynamic downscaling atmospheric model system coupled with a rainfall-runoff model
to hindcast an example of reservoir water management in the semi-arid region of Northeast Brazil (NEB). A regional atmospheric
spectral model (RSM) is driven by the outputs of an atmospheric general circulation model (AGCM), itself forced by the observed
sea surface temperature over the World Ocean. Daily precipitation simulated by the RSM was then used as the input to a hydrological
rainfall-runoff model for the Upper Jaguaribe River Basin to estimate inflows at the Orós Reservoir in the state of Ceará.
A hindcast analysis of precipitation was performed during the rainy season over NEB (January to June) from 1971 to 2000. The
RSM captured the precipitation variability relatively well when a probability density function (PDF) was used to correct the
numerical bias. Three hindcast series of inflow using (i) the observed rainfall, (ii) the simulated rainfall before the PDF
correction, and (iii) the simulated rainfall after the PDF correction were performed during the study period and then compared
to the series of observed inflow. The atmospheric-rainfall-runoff “cascade” model efficiency was evaluated by comparing the
Orós Reservoir release decisions from different scenarios based on observed, simulated (RSM, RSM-PDF), and mean historical
reservoir inflows. The cascade model has the potential, relatively well balanced during dry, normal or wet years, to be a
useful tool to correctly forecast the decision managements of reservoirs in the semi-arid region of NEB. Additional progress
in the numerical simulation is however necessary to improve the performance. 相似文献
998.
L Zamai M Ahmad IM Bennett L Azzoni ES Alnemri B Perussia 《Canadian Metallurgical Quarterly》1998,188(12):2375-2380
Mature natural killer (NK) cells use Ca2+-dependent granule exocytosis and release of cytotoxic proteins, Fas ligand (FasL), and membrane-bound or secreted cytokines (tumor necrosis factor [TNF]-alpha) to induce target cell death. Fas belongs to the TNF receptor family of molecules, containing a conserved intracytoplasmic "death domain" that indirectly activates the caspase enzymatic cascade and ultimately apoptotic mechanisms in numerous cell types. Two additional members of this family, DR4 and DR5, transduce apoptotic signals upon binding soluble TNF-related apoptosis-inducing ligand (TRAIL) that, like FasL, belongs to the growing TNF family of molecules. Here, we report that TRAIL produced or expressed by different populations of primary human NK cells is functional, and represents a marker of differentiation or activation of these, and possibly other, cytotoxic leukocytes. During differentiation NK cells, sequentially and differentially, use distinct members of the TNF family or granule exocytosis to mediate target cell death. Phenotypically immature CD161(+)/CD56(-) NK cells mediate TRAIL-dependent but not FasL- or granule release-dependent cytotoxicity, whereas mature CD56(+) NK cells mediate the latter two. 相似文献
999.
OBJECTIVES: To evaluate the incidence and severity of vesical neck strictures and urinary incontinence after radical retropubic prostatectomy (RRP) for prostate cancer. METHODS: Between August 1983 and December 1991, 481 consecutive patients underwent RRP by 1 of 2 senior surgeons. Strictures were treated by passing a urethral sound. Incontinence was measured by asking patients for a daily "pad count" of pads required to control urinary leakage. Results were compared to patient age, tumor volume, number of neurovascular bundles spared, preoperative urinary complaints, and previous transurethral resection of the prostate. RESULTS: Of 456 patients with adequate follow-up to determine stricture formation, 82.5% had no strictures, 6.8% required a single dilation, 3.7% required 2 dilations, 3.1% required 3 dilations, and 3.9% required more than 3 dilations. Risk of stricture formation was unrelated to every variable studied. Of 458 patients with adequate follow-up to determine recovery of continence, 80.1% required no pads, 8.1% required 1 to 2 pads a day, 6.6% required 3 to 5 pads a day, and 5.2% were totally incontinent 1 year or more after surgery. Incontinence was closely associated with postoperative urinary urgency. CONCLUSIONS: Strictures are a common but easily managed complication of RRP for prostate cancer. Despite substantial surgical experience, we report a somewhat higher rate of postoperative incontinence than other recently reported series. Our experience is more closely matched by published surveys of patient-reported complications after RRP. 相似文献
1000.
For almost twenty years certificate-of-need (CON) regulations have protected existing hospitals from unrestricted competition in services. Although the explicit purpose of CON regulation was to prevent hospitals from duplicating services and investing in costly excess capacity, it has been unsuccessful in accomplishing this goal. On the other hand, CON policies have, we suggest, been pursued with the implicit aim of "cross subsidization," that is, regulators have used their power to issue licenses and restrict competition in order to create an incentive to hospitals to provide high levels of care to the indigent population. Posner (1971) has noted that to achieve cross subsidization, entry into lucrative services must be restricted. We present evidence that CON licenses have been used to promote the internal subsidization of indigent care in probit analysis, based on data from Florida spanning the period 1983-89. While this method of financing indigent care may be preferred by legislators who do not want to face the political consequences of raising taxes to pay for the service, it has troubling implications for the hospital provision of indigent care, especially in an era of CON deregulation. 相似文献