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991.
BACKGROUND: To assess the relationship between placental inflammation, umbilical artery Doppler waveforms and fetal biophysical profile score, umbilical artery Doppler studies and fetal biophysical evaluations were performed in 24 preterm pregnants with premature rupture of membranes (PPROM). SUBJECTS: After delivery, the placentas were microscopically examined and two subgroups were formed including noninflamed or inflamed placentas. RESULTS: In the first group, which includes 14 cases with no histological signs of placental inflammation, we found increased systolic/diastolic ratio only in one patient, whereas in the second group including ten cases with microscopically proven inflammation, nine were found to have increased systolic/diastolic ratios (p < 0.05). Mean systolic/diastolic ratio in the first and the second groups were 2.74 +/- 0.18 and 4.64 +/- 0.93 respectively (p < 0.001). Mean biophysical profile score was 9 +/- 1.04 in the first group and 7 +/- 1.05 in the second group (p < 0.001). CONCLUSION: Abnormal biophysical profile scores along with increased arterial systolic/diastolic ratios have been shown to be the markers of impending clinical infection. 相似文献
992.
K Hayashida J Ooi K Omagari K Makiyama S Kohno 《Canadian Metallurgical Quarterly》1997,94(11):730-738
One of the shortcomings of percutaneous ethanol injection therapy (PEIT) for hepatocellular carcinoma (HCC) is that many sessions are necessary to accomplish the treatment. This may be caused by which the ultrasonography (US) image does not reflect correctly to the kinetics of injected ethanol into HCC nodule. It is considered that number of treatment sessions are able to be reduced if we just enough injected labelled ethanol under US into HCC nodule. Therefore, we tried PEIT by ethanol mixed with CO2 microbubble (CO2 ethanol). The injected CO2 ethanol was aquired as hyperechoic image without strong acoustic shadow to the end of injection. Consequently we could reduce the number of treatment sessions to almost 1 for lesions < or = 3 cm in diameter and markedly reduce total dose of injected ethanol. The detectable rate of CO2 ethanol leaked out HCC nodule was high. No serious complication occurred. There have been only 1 lesion of local recurrence and no case of intrahepatic and peritoneal dissemination for 11.5 months on average of observation after PEIT by CO2 ethanol (CO2PEIT). These findings suggest that CO2PEIT is useful method for reducing the number of treatment sessions and total dose of injected ethanol, moreover preventing complication by ethanol leakage. 相似文献
993.
S Higashiyama M Horikawa K Yamada N Ichino N Nakano T Nakagawa J Miyagawa N Matsushita T Nagatsu N Taniguchi H Ishiguro 《Canadian Metallurgical Quarterly》1997,122(3):675-680
The availability of an analgesic compound devoid of the side effects associated with the commonly used opioid and nonsteroidal antiinflammatory drugs would be useful during the perioperative period. Although adenosine has analgesic and anesthetic-sparing properties, it also produces dose-dependent cardiovascular depression. Inhibitors of adenosine kinase may be able to provide analgesia without producing acute cardiovascular or respiratory depression. This preliminary study investigated the effects of a novel adenosine kinase-inhibiting drug, GP683, on the minimum alveolar anesthetic concentration (MAC) of desflurane in dogs. Seven mongrel dogs were administered one of three different GP683 dose regimens (or the solvent) by intravenous infusion on separate occasions according to a cross-over study design. After determining the baseline desflurane MAC value, GP683 was infused at 75, 150, or 300 microg x kg(-1) x min(-1) for 5 min as a loading dose, followed by 15, 30, or 60 microg x kg(-1) x min(-1) for an additional 85 min to maintain a stable plasma drug level. The desflurane MAC was redetermined 30-90 min after starting the study drug or vehicle infusion, and 30-90 min and 120-180 min after termination of the infusion. Cardiovascular variables and plasma concentrations of GP683 were determined at specific intervals before, during, and after the MAC determinations. The three GP683 dose regimens produced 22%, 31%, and 50% decreases in the desflurane MAC, respectively. In addition, there was good correlation between the decrease in desflurane MAC and the plasma GP683 concentration (r = -0.78). Although the mean arterial pressure (MAP) was decreased up to 25% by the highest infusion rate of GP683, adjustments in the desflurane concentration to an equi-MAC value resulted in normalization of the MAP values. Furthermore, GP683 produced no changes in heart rate. In conclusion, the adenosine kinase-inhibiting drug, GP683, produced dose-dependent decreases in the desflurane MAC of dogs without producing untoward hemodynamic changes. IMPLICATIONS: An investigational drug (GP683) that can increase the levels of an important endogenous substance in the body (adenosine) has been found to decrease the anesthetic requirement in dogs without producing adverse effects on the cardiovascular system. 相似文献
994.
995.
The free fraction of pertechnetate in 99Tcm radiopharmaceuticals has to be tested for quality control reasons in line with the European Pharmacopoeia. Such quality control is often performed by miniaturized chromatographic methods. There are several recommended methods in the literature for quality control of the same radiopharmaceuticals, though it is unlikely that all methods are equivalent. Some of these methods were compared, taking into account different parameters (spot size, time required, analytical artifacts, true separation and shape of the chromatographic peaks, ease of handling), to verify the best method for the control of each radiopharmaceutical. It would appear that instant thin layer chromatography silica gel is the best support for these miniaturized methods, using MEK as solvent to check DTPA, DMSA, gluconate, pyrophosphate, medronate and phytate; NaCl 20% solution is the best solvent for IDA derivatives, human albumin and albumin particles (microspheres, macroaggregates). 相似文献
996.
Kang W.P. Wisitsora-at A. Davidson J.L. Kerns D.V. 《Electron Device Letters, IEEE》1998,19(10):379-381
A boron-doped diamond field emitter diode with ultralow turn-on voltage and high emission current is reported. The diamond field emitter diode structure with a built-in cap was fabricated using molds and electrostatic bonding techniques. The emission current versus anode voltage of the capped diamond emitter diode with boron doping, sp2 content, and vacuum thermal electric (VTE) treatment shows a very low turn-on voltage of 2 V. A high emission current of 1 μA at an anode voltage of less than 10 V can be obtained from a single diamond tip. The turn-on voltage is significantly lower than comparable silicon field emitters 相似文献
997.
往复式压缩机管道的防振设计 总被引:1,自引:0,他引:1
分析了往复式压缩机管道产生振动的原因及影响因素,提出解决管道振动的方法及对策。 相似文献
998.
V Darsonval V Berthet P Hubault C Crouzet L Fernandez 《Canadian Metallurgical Quarterly》1997,42(6):594-602
Enucleation frequently and progressively causes an enophtalmus and atrophia of the inferior eyelid, thereby leading to a height deficiency. Buccal mucous grafts give rise to phenomena such as secondary retraction. This may have complex and painful post-operative outcomes. However, when a septal chondromucous graft is performed, the height in the inferior palpebral part becomes more aesthetic, more retentive and quickly allows the wearing of a more voluminous prosthesis. Thus, the notinable enophtalmus can be corrected and the aesthetic quality of the looking is substantially restored. The authors report this surgical procedure and the results obtained with 21 patients which appear to be particularly promising. 相似文献
999.
The past decade has witnessed an enormous increase in our knowledge of the variety and complexity of neuropathological and neurochemical changes in Alzheimer's disease. Although the disease is characterized by multiple deficits of neurotransmitters in the brain, this overview emphasizes the structural and neurochemical localization of the elements of the acetylcholine system (choline acetyltransferase, acetylcholinesterase, and muscarinic and nicotinic acetylcholine receptors) in the non-demented brain and in Alzheimer's disease brain samples. The results demonstrate a great variation in the distribution of acetylcholinesterase, choline acetyltransferase, and the nicotinic and muscarinic acetylcholine receptors in the different brain areas, nuclei and subnuclei. When stratification is present in certain brain regions (olfactory bulb, cortex, hippocampus, etc.), differences can be detected as regards the laminar distribution of the elements of the acetylcholine system. Alzheimer's disease involves a substantial loss of the elements of the cholinergic system. There is evidence that the most affected areas include the cortex, the entorhinal area, the hippocampus, the ventral striatum and the basal part of the forebrain. Other brain areas are less affected. The fact that the acetylcholine system, which plays a significant role in the memory function, is seriously impaired in Alzheimer's disease has accelerated work on the development of new drugs for treatment of the disease of the 20th century. 相似文献
1000.