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991.
992.
BACKGROUND: Propofol and fentanyl infusion rates should be varied according to the patient's responsiveness to stimulation to maintain satisfactory anesthetic and operative conditions. However, somatic and autonomic responses to various noxious stimuli have not been investigated systematically for intravenous propofol and fentanyl anesthesia. METHODS: Propofol and fentanyl were administered via computer-assisted continuous infusion to provide stable concentrations and to allow equilibration between plasma-blood and effect-site concentrations. The propofol concentrations needed to suppress eye opening to verbal command and motor responses after 50-Hz electric tetanic stimulation, laryngoscopy, tracheal intubation, and skin incision in 50% or 95% of patients (Cp50 and Cp95) were determined at fentanyl concentrations of 0.0, 1.0, 2.0, 3.0, and 4.0 ng/ml in 133 patients undergoing lower abdominal surgery. The ability of propofol with fentanyl to suppress hemodynamic reactions in response to various noxious stimuli also was evaluated by measuring arterial blood pressure and heart rate before and after stimulation. RESULTS: The various Cp50 values for propofol alone (no fentanyl) for the various stimuli increased in the following order: Cp50loss of consciousness, 4.4 microg/ml (range, 3.8-5.0); Cp50tetanus, 9.3 microg/ml (range, 8.3-10.4); Cp50laryngoscopy, 9.8 microg/ml (range, 8.9-10.8); Cp50skin incision, 10.0 microg/ml (range, 8.1-12.2); and Cp50intubation, 17.4 microg/ml (range, 15.1-20.1; 95% confidence interval). The reduction of Cp50loss of consciousness, with fentanyl was minimal; 11% at 1 ng/ml of fentanyl and 17% at 3 ng/ml of fentanyl. A plasma fentanyl concentration of 1 ng/ml (3 ng/ml) resulted in a 31-34% (50-55%) reduction of the propofol Cp50s for tetanus, laryngoscopy, intubation, and skin incision. Propofol alone depresses prestimulation blood pressure but had no influence on the magnitude blood pressure or heart rate increase to stimulation. Propofol used with fentanyl attenuated the systolic blood pressure increases to various noxious stimuli in a dose-dependent fashion. CONCLUSIONS: The authors successfully defined the propofol concentration required for various stimuli. Tracheal intubation was the strongest stimulus. The absence of somatic reactions for propofol does not guarantee hemodynamic stability without fentanyl. Propofol with fentanyl was able to suppress motor and hemodynamic reactions to various noxious stimuli. 相似文献
993.
BACKGROUND AND METHODS: To elucidate the effect of hyperglycemia on disaccharidase activities, the specific and total activities of the disaccharidases were measured in the intestinal mucosa and kidney cortex of diabetic and hyperglycemic rats. The diabetes was induced with an intraperitoneal injection of streptozotocin (60 mg/kg). The rats were made hyperglycemic with an intravenous instillation of a solution containing 40% dextrose monohydrate at a rate of 1.5 ml/h for 24 h. RESULTS: The blood glucose level was 387+/-45 mg/dl and 382+/-35 mg/dl (mean +/- standard deviation) in diabetic and hyperglycemic rats, respectively. In diabetic rats the intestinal maltase, sucrase, and lactase activities were significantly higher than those in control rats. Similarly, disaccharidase activities in hyperglycemic rats were significantly higher than those in control rats. The renal maltase activity in diabetic rats was significantly lower than that in control rats. The maltase activity in hyperglycemic rats, however, was not significantly different from that in control rats. CONCLUSIONS: These results suggest that 1) hyperglycemia directly increases the activities of intestinal maltase, sucrase, and lactase; 2) hyperglycemia does not influence renal maltase activity; and 3) hyperglycemia is partly responsible for increased activities of intestinal disaccharidases in diabetes mellitus. 相似文献
994.
995.
Synthesis of Cs–aluminosilicate zeolites and thermal phase transformation from BIK to CAS frameworks
The hydrothermal synthesis of zeolite from a gel containing Cs to some alkali cations is thoroughly investigated, and a new route for the synthesis of CAS-type zeolite is found by the thermal treatment of BIK-type zeolite, which was prepared by the conventional synthesis method from aluminosilicate gel containing cesium and additional alkali metal ions. The effect of the alkali cations on the phase transformation of BIK into CAS at 900 °C is also investigated. It is found that lithium cations play an important role in the transformation and that the time required for the transformation into CAS decreases with the lithium content in the starting mixture. The required time for the transformation in potassium-containing BIK is more than that in lithium-containing BIK. The mechanism of structural transformation is considered. 相似文献
996.
Effects of oleic acid or triolein on lymphatic recovery of docosahexaenoic acid (DHA) given as an ethyl ester were examined
in rats with cannulated thoracic ducts. Lymphatic recovery of ethyl DHA given with oleic acid or triolein was significantly
higher than in rats given ethyl DHA alone. DHA distrbuted almost exclusively at the 1-and 3-position of triglyceride in lymph
collected at 0–3 h after the administration, when it was given with oleic acid or triolein. A small part of DHA distributed
at the 2-position when ethyl DHA was the sole fatty acid given. Oleic acid given as free acid or triolein with ethyl DHA was
a major fatty acid at the 2-position. Intramolecular distribution of DHA and oleic acid in lymph triglyceride was similar
when ethyl DHA was given with oleic acid or triolein. 相似文献
997.
H A Andrianisa A Ito A Sasaki M Ikeda J Aizawa T Umita 《Water science and technology》2006,54(8):121-128
The behaviour of As(III), As(V), MMA(v) and DMA(v) in batch activated sludge process were investigated. Experiments were carried out by using aerobic and anoxic reactors with an initial As concentration of 100 microjg I(-1). Under aerobic condition, As(III) was oxidized to As(V) within 9 hours, some part of MMA(v) was methylated to DMA(v) and some other part was demethylated to As(III), which in turn was immediately oxidized to As(V). Under anoxic condition, As(V) was reduced to As(III) within the same time-course. No significant transformation occurred during experiments conducted with DMA(v). It was found that all reactions were biologically mediated. The overall As removal was low (< 20%) during the experiments. Although a relationship seems to exist between the sludge concentration and As removal, it is concluded, under the conditions of our study, that the activated sludge process cannot remove arsenicals efficiently. However, it can control their transformations well. Thus, if associated with an appropriate technology, the activated sludge can be used for As pre-oxidation to treat As contaminated wastewaters. Finally, care must be taken on possible presence of MMA(v) in the influent of any wastewater treatment plant as it can be easily oxidized by the activated sludge. 相似文献
998.
In order to clarity the multiple-step progression from solar keratosis to squamous cell carcinoma, aberrations of the p53 gene (exons 2-11) and ras genes (exons 1 and 2) in solar keratosis and squamous cell carcinoma were investigated by polymerase chain reaction and single-strand conformation polymorphism analysis. In a series of Japanese patients, eight of 27 (30%) samples of solar keratosis and three of six (50%) samples of squamous cell carcinoma showed structural abnormalities in the p53 gene. Only one solar keratosis (4%) showed a point mutation in the Ha-ras gene but not in the p53 gene. Among these cases, no mutation of ras genes could be detected in squamous cell carcinoma. Simultaneous mutation of ras genes and the p53 gene was not detected in any cases of either solar keratosis or squamous cell carcinoma. It is concluded that aberrations of the p53 gene and ras genes are induced through independent processes of ultraviolet irradiation in the course of carcinogenic change from solar keratosis to squamous cell carcinoma. 相似文献
999.
Eto S. Matsumiya M. Takita M. Ishii Y. Nakamura T. Kawabata K. Kano H. Kitamoto A. Ikeda T. Koga T. Higashiho M. Serizawa Y. Irabashi K. Tsuboi O. Yokoyama Y. Taguchi M. 《Solid-State Circuits, IEEE Journal of》1998,33(11):1697-1702
This paper describes the key technologies used in a 1-Gb synchronous DRAM. This DRAM was developed according to a new cell-operating concept in which a ground-level (Vss) precharged bit line with a negative word-line reset scheme enables a nonboosted 2.1-V word-line architecture. Total power consumption is less than that of the conventional half-Vcc precharged bit-line scheme. We also propose a vernier-type, high-accuracy delay-locked-loop circuit realizing ±20-ps quantization errors for clock recovery and skew elimination 相似文献
1000.
Y Shigematsu M Hamada T Ohtsuka H Hashida S Ikeda T Kuwahara Y Hara K Kodama K Hiwada 《Canadian Metallurgical Quarterly》1998,11(10):1171-1177
Left ventricular hypertrophy (LVH) is an independent cardiovascular risk factor. It has not been established, however, whether left ventricular geometry is an independent predictor of extracardiac target organ damage in essential hypertension. Study groups were classified according to relative wall thickness: 27 patients with concentric LVH and 50 patients with eccentric LVH. Age and left ventricular mass indexes of two groups were matched. As indexes of extracardiac target organ damage, retinal funduscopic grade, and serum creatinine level were measured. The severity of hypertensive retinopathy and the renal involvement were more severe in patients with concentric LVH than in patients with eccentric LVH. Extracardiac target organ damage was consistently higher in patients with concentric LVH than in those with eccentric LVH. Systemic hemodynamics paralleled ventricular geometric patterns, with higher peripheral resistance and lower aortic compliance in patients with concentric LVH, whereas end-diastolic volumes and stroke volumes were higher in patients with eccentric LVH than in patients with concentric LVH. In addition, total peripheral resistance was related to retinal fundoscopic grade (r = 0.41, P < .01), and serum creatinine level (r = 0.28, P < .05). Even in the presence of an identical degree of LVH, echocardiographically determined left ventricular geometry may provide a further independent stratification of extracardiac target organ damage in essential hypertension. 相似文献