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21.
During the time period of the last 12 years the incidence of the endometrium carcinoma in the whole CSSR rised to 155,5% in the consideration of the incidence in the years 1961 to 1963. In the same time period the incidence of the ovarial carcinoma has grown up to 117,8% only, what seems to be still in the limits of average incidence shift of all female malignancies in the CSSR (117,1%). The rising incidence of endometrium carcinoma affects primarily the elderly women, but testiefies also that this malignancy is among them today much more frequent. Therefore the rising incidence cannot be explained only as a manifestation of elderly of the female population. In agreement with this reality the endometrium carcinoma is today diagnosed significantly more frequently also among the younger women (at least since 40 years of age). The totals of all endometrium carcinomas rised even more than incidence. The gynaecologists meet today 162% of such malignancies in comparison with the numbers in the years 1961-1963. It means that in the whole CSSR yearly 500 endometrium carcinomas more are diagnosed than before 12 years. The incidence of cervix carcinoma dropped during the same period significantly and the endometrium carcinoma became therefore nearly as frequent as cervical malignancy (1:1,2). Possible reasons of these frequency changes are discussed. 相似文献
22.
One approach to solving the equivalence problem for certain families of context free languages is through the use of ‘transformation trees’. We explore this approach in general. The methods developed provide a clear and complete proof of the decidability of the equivalence problem for ‘simple’ languages. It is shown how to decide the equivalence problem for two deterministic context free languages, one of which is simple. 相似文献
23.
V Bláha Z Zadák M Bláha E Havel D Solichová M Brátová J Maly L Kmonícek 《Canadian Metallurgical Quarterly》1998,137(14):424-429
LDL (low density lipoprotein) - apheresis has been established as an alternative management of severe hypercholesterolaemia after failure of conventional diet and drug therapy. General indication criteria for LDL-apheresis have yet been established. Indication guidelines in USA, Europe and japan are based on whether coronary heart disease is present and on the degree of lDL cholesterol elevation after treatment with diet and maximal drug therapy. It is reasonable to consider LDL apheresis therapy for: 1. patient with coronary heart disease and LDL cholesterol 4.9 mmol/l (190 mg/dl); 2. patients without coronary heart disease, but at high risk for disease (due to an LDL cholesterol above 6.4 mmol/l (250 mg/dl), a first-degree relative with premature coronary heart disease, and the presence of one or more additional risk factor. The therapeutical goal with present coronary heart disease is lDL cholesterol less than 3.4 mmol/l (130 mg/dl), with asymptomatic coronary heart less than 5.2 mmol/l (200 mg/dl). In addition, LDL apheresis is recommended for the management of all patients with homozygous familial hypercholesterolaemia due to the very high risk of coronary heart disease and the poor response to usual lipid-lowering treatments. In the end present two typical cases, treated by LDL-apheresis. 相似文献
24.
Timothy F. Havel 《Journal of Symbolic Computation》1991,11(5-6)
Distance geometry provides us with an implicit characterization of the Euclidean metric in terms of a system of polynomial equations and inequalities. With the aid of computer algebra programs, these equations and inequalities in turn provide us with a coordinate-free approach to proving theorems in Euclidean geometry analytically. This paper contains a brief summary of the mathematical results on which this approach is based, together with some examples showing how it is applied. In particular, we show how it can be used to derive the topological structure of a simple linkage mechanism. 相似文献
25.
This article examines the place of analytical models in realtime performance management applications. The main objectives are to define, specify and implement a system based on a composite model that provides the optimal software environment for performance analysis and tuning of heterogeneous networks. 相似文献
26.
M. Tvrdý S. Havel L. Hyspecká K. Mazanec 《International Journal of Pressure Vessels and Piping》1981,9(5):355-365
The variation of with time to fracture and the threshold values of in an hydrogen environment were measured for four CrMo and CrMoV pressure vessel steels in various conditions of heat treatment. The CrMoV grades displayed higher thresholds, suggesting that they are less susceptible to hydrogen embrittlement than CrMo grades of comparable strength. The findings were analysed with regard to the concurrent presence of various alloying elements and their effects on the microsegregation of detrimental impurity elements at the austenitic grain boundaries, where these harmful elements can, in conjunction with hydrogen, cause intercrystalline embrittlement. Studies were also made of the kinetics of stable crack growth in these materials. 相似文献
27.
M Ehrlich E Knolle R Ciovica P B?ck E Turkof M Grabenw?ger F Cartes-Zumelzu A Kocher H Pockberger WC Fang E Wolner M Havel 《Canadian Metallurgical Quarterly》1999,117(2):285-291
BACKGROUND: This study was conducted to investigate the effect of memantine, a noncompetitive N-methyl-d-aspartate receptor antagonist, on the neurologic outcome of spinal cord ischemia after aortic occlusion. MATERIALS AND METHODS: New Zealand White rabbits were anesthetized and spinal cord ischemia was induced for 40 minutes by infrarenal aortic occlusion. Animals were randomly allocated to 3 groups. Group 1 (n = 8, control) received no pharmacologic intervention, group 2 (n = 8) received intra-aortic memantine infusion (20 mg/kg) after aortic crossclamping, and group 3 (n = 8) was treated with systemic memantine infusion (20 mg/kg) 45 minutes before aortic occlusion. Neurologic status was scored by the Tarlov system (in which 4 is normal and 0 is paraplegia) at 12, 24, 36, and 48 hours after the operation. Lumbar spinal root stimulation potentials and motor evoked potentials from lower limb muscles were monitored before, during, and after the operation. After the animals were killed, the spinal cords were studied histopathologically. RESULTS: All potentials disappeared shortly after aortic crossclamping. They returned earlier in both memantine-treated groups than in the placebo group. Histologic examination of spinal cords revealed a few abnormal motor neurons in memantine-treated rabbits but found extensive injury in the control group. At 12 hours the median Tarlov scores were 0 in the control group (group 1), 2 in the intra-aortic memantine group (group 2, P =.001 versus control), and 3 in the systemic group (group 3, P =.0002 versus control). At 24 hours median Tarlov scores were 0, 2.5 (P =.0002), and 4 (P =. 0002), respectively. Finally, at both 36 and 48 hours median Tarlov scores were 0, 3 (P =.0006), and 4 (P =.0002), respectively. CONCLUSION: Memantine significantly reduced neurologic injury related to spinal cord ischemia and reperfusion after aortic occlusion. 相似文献
28.
WM Mueller FM Gregoire KL Stanhope CV Mobbs TM Mizuno CH Warden JS Stern PJ Havel 《Canadian Metallurgical Quarterly》1998,139(2):551-558
Circulating leptin secreted from adipocytes is correlated with fat mass and plasma insulin concentrations in humans and rodents. Plasma leptin, insulin, and glucose decrease during fasting and increase after refeeding; however, the underlying mechanisms regulating the changes of leptin secretion are not known. To investigate the role of insulin-stimulated glucose metabolism in the regulation of leptin secretion, we examined the effects of insulin and inhibitors of glucose transport and metabolism on leptin secretion from rat adipocytes in primary culture. Insulin (0.16-16 nM) increased leptin secretion over 96 h; however, the increase in leptin was more closely related to the amount of glucose taken up by the adipocytes (r = 0.64; P < 0.0001) than to the insulin concentration per se (r = 0.20; P < 0.28), suggesting a role for glucose transport and/or metabolism in regulating leptin secretion. 2-Deoxy-D-glucose (2-DG), a competitive inhibitor of glucose transport and phosphorylation, caused a concentration-dependent (2-50 mg/dl) inhibition of leptin release in the presence of 1.6 nM insulin. The inhibitory effect of 2-DG was reversed by high concentrations of glucose. Two other inhibitors of glucose transport, phloretin (0.05-0.25 mM) and cytochalasin-B (0.5-50 microM), also inhibited leptin secretion. Inhibition of leptin secretion by these agents was proportional to the inhibition of glucose uptake (r = 0.60 to 0.86; all P < 0.01). Two inhibitors of glycolysis, iodoacetate (0.005-1.0 mM) and sodium fluoride (0.1-5 mM), produced concentration-dependent inhibition of leptin secretion in the presence of 1.6 nM insulin. In addition, both 2-DG and sodium fluoride markedly decreased the leptin (ob) messenger RNA content of cultured adipocytes, but did not affect 18S ribosomal RNA content. We conclude that glucose transport and metabolism are important factors in the regulation of leptin expression and secretion and that the effect of insulin to increase adipocyte glucose utilization is likely to contribute to insulin-stimulated leptin secretion. Thus, in vivo, decreased adipose glucose metabolism may be one mechanism by which fasting decreases circulating leptin, whereas increased adipose glucose metabolism would increase leptin after refeeding. 相似文献
29.
The traditional approach in detecting sets of concurrent and/or parallel lines is to first detect lines in the image and then find such groups of them which meet the concurrence condition. The Hough Transform can be used for detecting the lines and variants of HT such as the Cascaded Hough Transform can be used to detect the vanishing points. However, these approaches disregard much of the information actually accumulated to the Hough space. This article proposes using the Hough space as a 2D signal instead of just detecting the local maxima and processing them. On the example of QRcode detection, it is shown that this approach is computationally cheap, robust, and accurate. The proposed algorithm can be used for efficient and accurate detection and localization of matrix codes (QRcode, Aztec, DataMatrix, etc.) and chessboard-like calibration patterns. 相似文献
30.
Jan Vitecek Jiri Petrek David Potesil Ladislav Havel Libuse Trnkova 《Electrochimica acta》2006,51(24):5087-5094
Nitrosation of sulfhydryl group of glutathione, which is highly reactive and is often found conjugated to other molecules via its sulfhydryl moiety, is one of many biological effects of the nitric oxide (NO). This process may serve as a signal event and/or as a deposition of NO to S-nitrosoglutathione (GSNO). Moreover, GSNO may release NO under specific conditions. That is why NO, which has a little lifetime itself, could be distribute for longer distances within the organism. Here, we studied and compared the basic electrochemical characteristics of biological active thiol compounds (GSH, oxidized glutathione and GSNO). In addition, observation of the decomposition process of GSNO using different electrochemical techniques followed. Primarily we studied the influence of scan rate and reducing agent (Tris(2-carboxyethyl)phosphine). The CV calibration equations were linear, R.S.D. about 5%. The detection limits of GSH, GSSG and GSNO expressed as 3 S/N were 9 nM, 4 nM and 20 nM, respectively. In addition, the use of NO selective carbon fibre electrode and cyclic voltammetry for the study of GSNO decomposition catalysed by copper(II) and iron(II) followed. 相似文献