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121.
We review 97 cases of SMCP, 79 of which were operated. The comparative results are presented. For those requiring surgery (i.e. those having hypernasality), it has been our experience that the use of a pharyngeal flap, alone or combined with a palatoplasty, is productive of better speech results than is a palatoplasty alone.  相似文献   
122.
1. A new open-circuit respiratory method was developed to estimate mixed venous PCO2 more rapidly and accurately than is possible with rebreathing techniques. 2. The subject breathes a mixture of CO2 in air from an open circuit. Carbon dioxide is added to the air flowing through the circuit at a rate such that the PCO2 in the inspired and expired gases (recorded continuously with a CO2 analyser) are almost identical. 3. Results from respiratory and cardiac patients showed that equilibrium occurred in less than 10 s. There was good agreement between the tensions of CO2 in the respiratory plateaux and in mixed venous and arterial blood withdrawn during equilibrium. 4. During exercise, the tensions of CO2 of the plateaux and arterial blood at equilibrium also showed good agreement. 5. It is suggested that the new method represents an improvement over rebreathing methods as equilibrium is achieved rapidly before the mixed venous tension rises from recirculation.  相似文献   
123.
We report a large right occipital falcine meningioma, the main presenting feature of which was ipsilateral hemifacial spasm. The patient was relieved of the hemifacial spasm after the supratentorial tumour was resected. The pathogenesis of hemifacial spasm is reviewed in light of this unusual case and the treatment of hemifacial spasm secondary to a tumour is discussed.  相似文献   
124.
Tyrosine kinases are involved in various intracellular signalling cascades of different cells: Genistein has been shown to inhibit tyrosine kinase in INS-1 cells, an insulin-secreting cell line (Verspohl et al., 1995). It is, however, not established how specific and selective the tyrosine kinase inhibitors and their controls are. The tyrosine kinase inhibitors genistein and tyrphostin 25 increased insulin release, but not their negative controls with isoflavonoid structure (daidzein and genistin). In addition to this short-term effect a long-term effect was investigated. Genistein (100 microM) time-dependently increased insulin mRNA levels in INS-1 cells. On the other hand the tyrosine kinase inhibitors tyrphostin 25 and lavendustin A (both at 100 microM), which are structurally different from genistein, failed to increase the insulin mRNA whereas daidzein and genistin, normally used as negative controls, increased insulin mRNA as potently as genistein did. However, an examination of the incubation medium revealed that genistin was degraded to genistein by about 50% probably by nonspecific glucosidases first seen after 2 hours of incubation; genistin, therefore, does not appear to be a proper control though often used in this way. In conclusion, the suitability of the compounds used in recent studies is doubtful since other effects than the inhibition of tyrosine kinases are possible. Whereas the involvement of tyrosine kinase in a short-term effect (insulin release) is obvious and clearly substantiated by using the established pharmacological tools (negative controls), the involvement of tyrosine kinases in long-term effects is not that clear; only compounds with isoflavonoid structure are effective independent whether they normally are thought to be inhibitors or negative controls. One has to be cautious in using the above-mentioned compounds in an uncritical way.  相似文献   
125.
We identified the cell cycle status of CD34(+) cells of steady-state bone marrow (BM) and peripheral blood (PB) obtained from healthy volunteers, and those of apherasis PB samples collected from healthy donors who had been administered granulocyte colony-stimulating factor (G-CSF). More than 10% of CD34(+) cells in BM were in S+G2/M phase. In contrast, regardless of whether G-CSF treatment was performed, less than 2% of CD34(+) cells in PB were cycling. BM CD34(+) cells showed greater VLA-4 expression and adherence to stromal cells than PB CD34(+) cells. In addition, when cycling and dormant BM CD34(+) cells were analyzed separately, the cells in S+G2/M phase expressed more VLA-4 and adhered to the stromal cell monolayer more efficiently than the cells in G0/G1 phase. Furthermore, this adhesion of CD34(+) cells to the stromal cell layer was almost completely inhibited by anti-VLA-4 antibody. Taken together, these results suggest that CD34(+) progenitors in G0/G1 phase of the cell cycle differ from those in S+G2/M phase in adhesiveness mediated by VLA-4 in the hematopoietic microenvironment.  相似文献   
126.
BACKGROUND: Traumatic aortic rupture is a relatively uncommon lesion that presents the cardiothoracic surgeon with unique challenges in diagnosis and management. To address controversial aspects of this disease, we reviewed our experience. METHODS: The study was performed by retrospective chart review. RESULTS: Forty-two patients with traumatic thoracic aortic ruptures were managed between January 1988 and June 1997. Nine arrived without vital signs and died in the emergency department. Admission chest radiographs were normal in 3 patients (12%) and caused significant delays in diagnosis. Four of 30 patients admitted with vital signs had rupture before thoracotomy and died. Twenty-six underwent aortic repair. In 1 patient repair was performed with simple aortic cross-clamping, whereas a second was managed with a Gott shunt. The remaining 24 patients had repair with partial left heart bypass. In 1 patient hypothermic circulatory arrest was required. Two patients (7.7%) died. There were no cases of new postoperative paraplegia in the bypass group. There was no morbidity directly attributable to the administration of heparin for cardiopulmonary bypass. CONCLUSIONS: In a discrete group of patients with traumatic rupture of the aorta, the rupture will become complete during the first few hours of hospital admission; aggressive medical treatment with beta-blockade and vasodilators in the interval before the operation is an essential aspect of management. Active distal circulatory support with partial left-heart bypass provides the optimal means of preventing spinal cord ischemia during repair of acute traumatic aortic rupture.  相似文献   
127.
128.
The decay of evanescent field intensity beyond a dielectric interface depends upon beam incident angle, enabling the 3-d distribution of fluorophores to be deduced from total internal reflection fluorescence microscopy (TIRFM) images obtained at multiple incident angles. Instrumentation was constructed for computer-automated multiple angle-TIRFM (MA-TIRFM) using a right angle F2 glass prism (n(r) 1.632) to create the dielectric interface. A laser beam (488 nm) was attenuated by an acoustooptic modulator and directed onto a specified spot on the prism surface. Beam incident angle was set using three microstepper motors controlling two rotatable mirrors and a rotatable optical flat. TIRFM images were acquired by a cooled CCD camera in approximately 0.5 degree steps for >15 incident angles starting from the critical angle. For cell studies, cells were grown directly on the glass prisms (without refractive index-matching fluid) and positioned in the optical path. Images of the samples were acquired at multiple angles, and corrected for angle-dependent evanescent field intensity using "reference" images acquired with a fluorophore solution replacing the sample. A theory was developed to compute fluorophore z-distribution by inverse Laplace transform of angle-resolved intensity functions. The theory included analysis of multiple layers of different refractive index for cell studies, and the anisotropic emission from fluorophores near a dielectric interface. Instrument performance was validated by mapping the thickness of a film of dihexyloxacarbocyanine in DMSO/water (n(r) 1.463) between the F2 glass prism and a plano-convex silica lens (458 mm radius, n(r) 1.463); the MA-TIRFM map accurately reproduced the lens spherical surface. MA-TIRFM was used to compare with nanometer z-resolution the geometry of cell-substrate contact for BCECF-labeled 3T3 fibroblasts versus MDCK epithelial cells. These studies establish MA-TIRFM for measurement of submicroscopic distances between fluorescent probes and cell membranes.  相似文献   
129.
A model is a mathematical representation of a system that can be used to explore the system in a number of ways: to determine the system's internal connections, to calculate properties of the system such as flow rates and pool sizes, and to make predictions about the system's behavior under different conditions. The use of modeling to explore whole-body metabolism is demonstrated using a compartmental model of zinc kinetics as an example. Because models are useful tools for exploring systems, a facility called a "model library" is being established on the Internet to provide access to working versions of published models.  相似文献   
130.
Previous studies have shown that the intestinal peristaltic reflex initiated by mucosal stimulation is mediated by release of 5-hydroxytryptamine (HT) from enterochromaffin cells; 5-HT acts via 5-HT4 receptors in rat and human, and via both 5-HT4 and 5-HT3 receptors in guinea pig to activate intramural sensory neurons that release calcitonin gene-related peptide. In this study, selective agonists and antagonists were used to examine the involvement of 5-HT4 and 5-HT3 receptors in colonic propulsion. The velocity of propulsion was measured with artificial fecal pellets introduced into the orad end of an isolated guinea pig colonic segment. Control velocity ranged from 0.5 to 3.3 mm/s; mean +/- S.E.M., 1.3 +/- 0.1 mm/s. The 5-HT4 antagonist, GR 113808A, and the 5-HT3 antagonist, LY 278584, decreased the velocity of pellet propulsion in a concentration-dependent fashion (39 +/- 2% and 47 +/- 1% decrease at 10 microM, respectively). A combination of both antagonists (10 microM each) was additive, decreasing the velocity by 82 +/- 3% to 84 +/- 4%. The selective 5-HT4 agonists, HTF 919 and R093877, as well as 5-HT in the presence of the 5-HT2a antagonist, ketanserin, increased the velocity of propulsion in a concentration-dependent fashion with EC50s of 6.9 +/- 0.1 nM, 37.4 +/- 1.0 nM, and 3.9 +/- 0. 1 nM, respectively. Compared with HTF 919, R093877 was less potent and appeared to be a partial agonist. All three agonists were effective at submicromolar concentrations; at concentrations above 1 microM, there was no increase in the velocity of propulsion. We conclude that the presence of fecal pellets triggers the release of 5-HT, which acts via both 5-HT3 and 5-HT4 receptors to regulate propulsive activity in guinea pig colon.  相似文献   
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