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31.
Renal function recovery (RFR), defined as the discontinuation of dialysis after 3 months of replacement therapy, is reported in about 1% of chronic dialysis patients. The role of personalized, intensive dialysis schedules and of resuming low‐protein diets has not been studied to date. This report describes three patients with RFR who were recently treated at a new dialysis unit set up to offer intensive hemodialysis. All three patients were females, aged 73, 75, and 78 years. Kidney disease included vascular‐cholesterol emboli, diabetic nephropathy and vascular and dysmetabolic disease. At time of RFR, the patients had been dialysis‐dependent from 3 months to 1 year. Dialysis was started with different schedules and was progressively discontinued with a “decremental” policy, progressively decreasing number and duration of the sessions. A moderately restricted low‐protein diet (proteins 0.6 g/kg/day) was started immediately after dialysis discontinuation. The most recent update showed that two patients are well off dialysis for 5 and 6 months; the diabetic patient died (sudden death) 3 months after dialysis discontinuation. Within the limits of small numbers, our case series may suggest a role for personalized dialysis treatments and for including low‐protein diets in the therapy, in enhancing long‐term RFR in elderly dialysis patients.  相似文献   
32.
Tungsten coil atomic emission spectrometry is an ideal technique for field applications because of its simplicity, low cost, low power requirement, and independence from cooling systems. A new, portable, compact design is reported here. The tungsten coil is extracted from an inexpensive 24 V, 250 W commercial light bulb. The coil is housed in a small, aluminum cell. The emission signal exits from a small aperture in the cell, while the bulk of the blackbody emission from the tungsten coil is blocked. The resulting spectra exhibit extremely low background signals. The atomization cell, a single lens, and a hand-held charge coupled device (CCD) spectrometer are fixed on a 1 × 6 × 30 cm ceramic base. The resulting system is robust and easily transported. A programmable, miniature 400 W solid-state constant current power supply controls the temperature of the coil. Fifteen elements are determined with the system (Ba, Cs, Li, Rb, Cr, Sr, Eu, Yb, Mn, Fe, Cu, Mg, V, Al, and Ga). The precision ranges from 4.3% to 8.4% relative standard deviation for repetitive measurements of the same solution. Detection limits are in the 0.04 to 1500 μg/L range. Accuracy is tested using standard reference materials for polluted water, peach leaves, and tomato leaves. For those elements present above the detection limit, recoveries range from 72% to 147%.  相似文献   
33.
Working memory (WM) deficits are common in HIV-seropositive (HIV+) individuals and can be amplified by manipulating a variety of task parameters, such as increasing memory load or information complexity. The authors investigated the role of timing in HIV-associated WM defects by varying the amount of time required to maintain information online while holding memory load and information complexity constant. The authors studied 50 HIV+ and 35 HIV-seronegative (HIV-) polydrug abusers abstinent at testing and well-matched on demographic variables. The HIV- group outperformed the HIV+ group across all stimulus-response time delays. HIV-associated WM defects are not critically dependent on the amount of time stimulus representations must be maintained and might be attributed to impaired encoding or retrieval of stimulus representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Information on natural concentrations or variability of secondary metabolites in marine organisms may be important both to ecological/evolutionary and applied approaches. A gas chromatographic procedure with an electron capture detector (GC-ECD) was developed to quantify the sesquiterpenoid elatol at the surface and within-thalli of 70 specimens of the red seaweed Laurencia obtusa. The concentration of elatol was highest within-thalli [9.89 mg g−1 of L. obtusa, dry weight (d.w.)], compared to lower values found at the surface [0.006 mg g−1 of L.obtusa (d.w.), or 0.5–10.0 ng cm−2]. This method provides a rapid and inexpensive quantification of small quantities of elatol, and probably may also be used to quantify other halogenated compounds usually found in red seaweeds.  相似文献   
36.
In the present work, the process of biodiesel production in a pilot plant has been studied using beef tallow as raw materials with methanol and potassium hydroxide as catalyst. The biodiesel quality is regulated by Brazilian specifications (Resolution 42) by the National Agency of Petroleum (ANP). The alkaline transesterification of animal fat with methanol produces a biodiesel with high quality and also with a good conversion rate. The process is possible but the economical viability must be improved by recovering methanol and glycerin. The obtained results have been used for industrial scale up of the process.  相似文献   
37.
This paper presents an experimental analysis of the confinement effects in steel–concrete composite columns regarding two parameters: concrete compressive strength and column slenderness. Sixteen concrete-filled steel tubular columns with circular cross section were tested under axial loading. The tested columns were filled by concrete with compressive strengths of 30, 60, 80, and 100 MPa, and had length/diameter ratios of 3, 5, 7, and 10. The experimental values of the columns’ ultimate load were compared to the predictions of 4 code provisions: the Brazilian Code NBR 8800:2008, Eurocode 4 (EN 1994-1-1:2004), AINSI/AISC 360:2005, and CAN/CSA S16-01:2001. According to the results, the load capacity of the composite columns increased with increasing concrete strength and decreased with increasing length/diameter ratio. In general, the code provisions were highly accurate in the prediction of column capacity. Among them, the Brazilian Code was the most conservative, while Eurocode 4 presented the values closest to the experimental results.  相似文献   
38.
The physical qualities of butter are affected by the physical properties of the cream used to make it. The objective of this study was to evaluate the effect of high-intensity ultrasound (HIU) on the physical properties of cream and butter. High-intensity ultrasound (frequency: 20 kHz, amplitude: 108 µm), often called sonication, was applied for 0, 10, 30, 60, and 90 s using a 1.27-cm-diameter tip to heavy cream (40% fat; 300 g) that was aged at 7.5°C with low agitation (40 rpm) for 90 min. Sonicated cream was churned at 7.5°C until butter grains were formed. The solid fat content (SFC), melting behavior, and average fat droplet size of cream were measured after HIU treatment. Butter was characterized by SFC and melting behavior immediately after production and was tested for SFC, melting behavior, and hardness after storage for 24 h at 5°C. High-intensity ultrasound did not affect the average fat droplet size of cream. Sonicating cream for 30, 60, and 90 s slightly decreased SFC due to the temperature increase (2–6°C) that occurred during HIU application. Two melting peaks were observed at approximately 17 and 33°C in all the cream samples. A significantly lower peak temperature was observed in cream sonicated for 10 s compared with creams sonicated for 30 and 60 s. A relatively shorter churning time of sonicated cream compared with nonsonicated cream was observed, possibly because HIU weakens the fat globule membrane. Two melting peaks were observed in all butter samples at approximately 16 and 33°C. Treatment with HIU for 10 to 60 s significantly increased the hardness of butter. When HIU was applied to cream for 10 s, the hardest butter was obtained, with the lowest onset temperatures and highest enthalpy values for both melting peaks. Treatment with HIU for 10 s promoted crystallization of low-melting-point triacylglycerols (TAG) during churning, which resulted in a harder material. Significantly lower enthalpy values for the high-melting-fraction TAG were observed in butters treated with HIU for 60 and 90 s compared with non-HIU-treated butter, which suggests that a longer duration of HIU promotes melting of high-melting-point TAG. The hardness of butter was correlated with the enthalpy values of the low-melting fraction and with total enthalpy values of fresh butter. However, further crystallization occurred in the butter during 24 h of storage at 5°C, and all differences in enthalpy values disappeared. In conclusion, exposure of cream to HIU can be used to modify the physical properties of butter, and the effects of HIU depend on the length of HIU treatment.  相似文献   
39.
Even though immunotherapy has radically changed the search for anticancer therapies, there are still many different pathways that are open to intervention with traditional small molecules. To expand our investigation in the anticancer field, we report here a new series of compounds in which our previous pyrazole and imidazopyrazole scaffolds are linked to a differently decorated phenyl ring through an acylhydrazone linker. Preliminary tests on the library were performed at the National Cancer Institute (USA) against the full NCI 60 cell panel. The best compounds among the imidazopyrazole series were then tested by immunofluorescence staining for their inhibition of cell proliferation, apoptosis induction, and their effect on the cell cycle and on microtubules. Two compounds, in particular 4-benzyloxy-3-methoxybenzyliden imidazopyrazole-7-carbohydrazide showed good growth inhibition, with IC50 values in the low-micromolar range, and induced apoptosis. Both compounds altered the cell-cycle phases with the appearance of polyploid cells. Immunofluorescence analysis evidenced microtubules alterations; tubulin polymerization assays and docking studies suggested the tubulin system to be the possible, although not exclusive, target of the new acylhydrazone series reported here.  相似文献   
40.
Plant specialized metabolites (SMs) play an important role in the interaction with the environment and are part of the plant defense response. These natural products are volatile, semi-volatile and non-volatile compounds produced from common building blocks deriving from primary metabolic pathways and rapidly evolved to allow a better adaptation of plants to environmental cues. Specialized metabolites include terpenes, flavonoids, alkaloids, glucosinolates, tannins, resins, etc. that can be used as phytochemicals, food additives, flavoring agents and pharmaceutical compounds. This review will be focused on Mediterranean crop plants as a source of SMs, with a special attention on the strategies that can be used to modulate their production, including abiotic stresses, interaction with beneficial soil microorganisms and novel genetic approaches.  相似文献   
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