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1.
During a 22-year period, 13 patients with hematologic diseases developed bacteremia caused by the Bacteroides fragilis group, with a frequency which remained almost unchanged. Nine patients (69%) had polymicrobial infections. Acute leukemia was the most common underlying disease. The lower intestinal tract (necrotizing enterocolitis and anorectal abscesses) was the most common source of infection. Prior antibiotic therapy was the most frequent host condition before bacteremia, followed by cancer chemotherapy, neutropenia, thrombocytopenia and hypoproteinemia. Septic shock occurred only in seven patients with polymicrobial infections. Six patients, including five with shock, died within a week of onset, while the other seven survived for at least three weeks. Despite its clinical similarity to aerobic gram-negative infection, bacteremia due to the B. fragilis group may well, therefore, be suspected particularly when neutropenic patients who present with lower intestinal symptomatology develop a persistent fever unresponsive to the initial empiric antibiotic therapy.  相似文献   
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A p-MOSFET structure with solid-phase diffused drain (SPDD) is proposed for future 0.1-μm and sub-0.1-μm devices. Highly doped ultrashallow p+ source and drain junctions have been obtained by solid-phase diffusion from a highly doped borosilicate glass (BSG) sidewall. The resulting shallow, high-concentration drain profile significantly improves short channel effects without increasing parasitic resistance. At the same time, an in situ highly-boron-doped LPCVD polysilicon gate is introduced to prevent the transconductance degradation which arises in ultrasmall p-MOSFETs with lower process temperature as a result of depletion formation in the p+-polysilicon gate. Excellent electrical characteristics and good hot-carrier reliability are achieved  相似文献   
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This paper deals with an advanced static Var compensator (ASVC) using quad-series voltage-source PAM inverters. The ASVC consists of four three-phase voltage-source inverters with a common dc capacitor and four three-phase transformers, each primary winding of which is connected in series with each other. Each inverter outputs a square-wave voltage, while the synthesized output voltage of the ASVC has a 24-step wave shape. This results not only in a great reduction of harmonic currents and dc voltage ripples but also in fewer switching and snubbing losses. In this paper, transient analysis is performed with the focus on the response of reactive power and the resonance between the dc capacitor and ac reactors. Experimental results obtained from a small-rated laboratory model of 10 kVA are also shown to verify analytical results based on the p-q transformation. The analytical results help in the design of system parameters such as the capacity of the dc capacitor and feedback gains.  相似文献   
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Changes in the brain lactate concentration in cerebral extracellular fluid (ECF) during intravenous infusion of glucose and local administration of glucose were investigated in adult, conscious, unrestrained rats, with a microdialysis probe in the posterior hippocampus. The rats were infused intravenously with either 25% sucrose solution or 25% glucose solution at a rate of 16.6 microliters.min-1.100 g-1 for three hours. The blood glucose concentration reached 17.0 +/- 2.6 mM at the end of the glucose infusion, and brain ECF glucose showed a parallel change with the blood glucose concentration and increased to 2.37 +/- 0.30 mM. However, blood and brain ECF glucose concentrations did not change in animals infused with the sucrose solution. On the other hand, the blood lactate concentration in the glucose-infused group also increased from 0.93 +/- 0.18 mM to 2.85 +/- 0.39 mM at the end of the glucose infusion, which was significantly higher than that measured in the sucrose-infused group. The blood lactate level in the glucose-infused group returned to the basal level by the end of the experiment. Brain ECF lactate concentrations increased from 1.21 +/- 0.06 mM to 1.69 +/- 0.11 mM in glucose-infused animals, but did not change in the sucrose-infused animals. The brain ECF lactate concentration showed a positive correlation with the brain ECF glucose concentration in glucose-infused animals. Another group of rats was administered glucose locally for 90 min after substitution of artificial cerebrospinal fluid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Using extracted human deciduous teeth undergoing physiologic root resorption, this author studied the ultrastructural and cytochemical features of odontoclasts. The scanning electron microscopic observation of trypsin-treated dentin and cementum surfaces of resorption lacunae showed the exposure of collagen fibrils and prominent loss of the peritubular matrices around the dentinal tubules. In the resorption lacunae formed in enamel, there was dissolution of either the rod or the interrod regions. The odontoclasts developed extensive ruffled borders apposed to these resorbing matrices and had round phagosomes containing tannic acid-stainable fine amorphous inclusions, which were identical to those in the extracellular canals of the ruffled borders. The odontoclasts did not phagocytose the collagen fibrils. The odontoclasts showed the enzymatic activities of the acid trimetaphosphatase and acid p-nitrophenyl phosphatase (p-NPPase) in the Golgi-lysosome system, the ruffled border region, and along the resorbing dentin surfaces. The p-NPPase activity was inhibited by sodium tartrate. Also, the odontoclasts showed H(+)-K(+)-ATPase activity in the cytoplasm along the plasma membranes including those of ruffled border and the limiting membranes of the lysosomes. These results suggest that: 1) the odontoclasts are associated with resorption of non-collagenous organic matrices and/or extracellularly-degraded collagenous fragments rather than the incorporation of intact collagen fibrils; 2) the odontoclasts release the hydrolytic enzymes onto the lacunal surfaces and/or the lysosomes for the extra/intracellular degradation of the organic matrices; and 3) they also have H(+)-K(+)-ATPase for extracellular demineralization of the inorganic crystals.  相似文献   
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Sub-50-nm CMOS devices are investigated using steep halo and shallow source/drain extensions. By using a high-ramp-rate spike annealing (HRR-SA) process and high-dose halo, 45-nm CMOS devices are fabricated with drive currents of 650 and 300 μA/μm for an off current of less than 10 nA/μm at 1.2 V with Toxinv =2.5 nm. For an off current less than 300 nA/μm, 33-nm pMOSFETs have a high drive current of 400 uA/μm. Short-channel effect and reverse short-channel effect are suppressed simultaneously by using the HRR-SA process to activate a source/drain extension (SDE) after forming a deep source/drain (S/D). This process sequence is defined as a reverse-order S/D (R-S/D) formation. By using this formation, 24-nm nMOSFETs are achieved with a high drive current of 800 μA/μm for an off current of less than 300 μA/μm at 1.2 V. This high drive current might be a result of a steep halo structure reducing the spreading resistance of source/drain extensions  相似文献   
10.
A new deep submicron double-poly self-aligned Si bipolar technology has been developed using a 0.3-μm design rule, a collector polysilicon trench electrode, and oxide-filled trench isolation. This technology is called “High-Performance Super Self-Aligned Process Technology” or HSST. 0.3-μm minimum patterning is achieved by electron-beam direct writing technology. The HSST bipolar transistor is 2.5 times smaller than the previous 1-μm SST-1B. Owing to its horizontal reduction and an fT of 22.3 GHz at Vce=1 V, the ECL gate attains 25.4 ps/G at 1.58 mA, which is a 30% improvement on the SST-1B. By including parasitic capacitances of the base polyelectrode and polyresistors, the ECL delay time is accurately simulated for low-power operation. It is shown that the HSST is a very promising technology for the development of future high-speed communication systems  相似文献   
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