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91.
When artists portray human faces, they generally endow their portraits with properties that render the faces esthetically more pleasing. To obtain insight into the changes introduced by artists, we compared Fourier power spectra in photographs of faces and in portraits by artists. Our analysis was restricted to a large set of monochrome or lightly colored portraits from various Western cultures and revealed a paradoxical result. Although face photographs are not scale-invariant, artists draw human faces with statistical properties that deviate from the face photographs and approximate the scale-invariant, fractal-like properties of complex natural scenes. This result cannot be explained by systematic differences in the complexity of patterns surrounding the faces or by reproduction artifacts. In particular, a moderate change in gamma gradation has little influence on the results. Moreover, the scale-invariant rendering of faces in artists' portraits was found to be independent of cultural variables, such as century of origin or artistic techniques. We suggest that artists have implicit knowledge of image statistics and prefer natural scene statistics (or some other rules associated with them) in their creations. Fractal-like statistics have been demonstrated previously in other forms of visual art and may be a general attribute of esthetic visual stimuli. 相似文献
92.
Giesen J Mueller K Schuberth E Wang L Zolliker P 《IEEE transactions on visualization and computer graphics》2007,13(6):1664-1671
Visualization algorithms can have a large number of parameters, making the space of possible rendering results rather high-dimensional. Only a systematic analysis of the perceived quality can truly reveal the optimal setting for each such parameter. However, an exhaustive search in which all possible parameter permutations are presented to each user within a study group would be infeasible to conduct. Additional complications may result from possible parameter co-dependencies. Here, we will introduce an efficient user study design and analysis strategy that is geared to cope with this problem. The user feedback is fast and easy to obtain and does not require exhaustive parameter testing. To enable such a framework we have modified a preference measuring methodology, conjoint analysis, that originated in psychology and is now also widely used in market research. We demonstrate our framework by a study that measures the perceived quality in volume rendering within the context of large parameter spaces. 相似文献
93.
The focus of this article is to review recent techniques in proteomic analysis of ocular fluids. These fluids include tears, aqueous humor, and vitreous, they will also be compared to serum analysis. Furthermore, we attempt to summarize some disease correlated biomarkers in ocular fluids that were discovered through different proteomic techniques in eye diseases like dry eye, glaucoma, age-related macular degeneration, uveitis, or diabetic retinopathy. This review is trying to point out the importance of these biomarkers for clinical applications. 相似文献
94.
Fentz AK Spörl M Spangenberg J List HJ Zornig C Dörner A Layer P Juhl H David KA 《Proteomics. Clinical applications》2007,1(6):536-544
Colorectal cancer is the second leading cause of cancer death, and it develops from benign colorectal adenomas in over 95% of patients. Early detection of these cancer precursors by screening tests and their removal can potentially eradicate more than 95% of colorectal cancers before they develop. To discover sensitive and specific biomarkers for improvement of pre‐clinical diagnosis of colorectal adenoma and cancer, we analysed in two independent studies (n = 87 and n = 83 patients) serum samples from colorectal cancer (stage III), colorectal adenoma and control patients using SELDI‐TOF‐MS. Extensive statistical analysis was performed to establish homogeneous patient groups based on their clinical data. Two biomarkers that were each able to distinguish control patients from either colorectal adenoma or colorectal cancer patients (p<0.001) were identified as transthyretin (pre‐albumin) and C3a‐desArg by MS/MS and were further validated by antibody‐based assays (radial immunodiffusion, ELISA). A combination of both proteins clearly indicated the presence of colorectal adenoma or carcinoma. Using a cut‐off of <0.225 g/L for transthyretin and >1974 ng/mL for C3a‐desArg, we found a sensitivity and specificity for colorectal adenoma of 96% and 70%, respectively. 相似文献
95.
Kaindl AM Zabel C Stefovska V Lehnert R Sifringer M Klose J Ikonomidou C 《Proteomics. Clinical applications》2007,1(7):640-649
Traumatic brain injury (TBI) is a major cause of morbidity and mortality among children and adolescents. To gain insight into developmental events influenced by TBI, we analyzed subacute mouse brain proteome changes in a percussion head trauma model at P7 ipsi- and contralateral to the site of injury. The comparison of brain proteomes of trauma mice and controls revealed reproducible changes in the intensity of 28 proteins (30 protein spots) in response to trauma. The changes detected suggest that TBI leads to apoptosis, inflammation, and oxidative stress. These changes were consistent with our results of histological and biochemical evaluation of the brains which revealed widespread apoptotic neurodegeneration, microglia activation, and increased levels of protein carbonyls. Furthermore, we detected changes in proteins involved in neuronal migration as well as axonal and dendritic growth and guidance, suggesting interference of trauma with these developmental events. 相似文献
96.
97.
98.
Werner Henning und Karl Herrmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1980,171(2):111-118
Zusammenfassung Blätter wie Früchte von 6 SortenPrunus domestica-Pflaumen enthalten hauptsächlich 3-Rutinoside, in geringerer Konzentration 3-Glucoside und 3-Galaktoside von Kämpferol und Quercetin Bowie Quercetin-3-rhamnosid. Dagegen weisen Pflaumen vonPrunus salicina (2 untersuchte Sorten) Kämpferol-3,7-bisrhamnosid und Kämpferol-3-arabinosyl-7-rhamnosid als Hauptflavonole auf. Hierdurch ist eine Unterscheidung beider Arten leicht and sicher mög-lich. Weiterhin konnten inSalicina-Pflaumen Kämpfe-rol-3-rutinosid sowie Quercetin-3-rhamnosid, -xylosid,-glucosid, -galaktosid, --l-arabinofuranosid and -rutinosid, auch Quercetin-7-rhamnosid and Kämpferol-7-glucosid nachgewiesen werden.Die Gesamtgehalte an Flavonolglykosiden lagen bei den untersuchten Pflaumensorten vonPrunus domestica (P. salicina) bei 2500–3340 (7170, 10350) ppm in Blättern and 20–52 (8, 24) in Früchten, jeweils bezogen auf Frischgewicht.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
Flavonol glycosides of plums of the species Prunus domestica L. and Prunus salicina lindley12. Phenolics of fruits
Summary Leaves and fruits from 6 cultivars ofPrunus domestica plums contain mainly 3-rutinosides; in smaller concentrations the 3-glycosides and 3-galactosides of kaempferol and quercetin as well as quercetin-3-rhamnoside are present. On the other hand, in plums ofPrunus salicina (2 examined cultivars) main flavonols are kaempferol-3,7-bisrhamnoside and kaempferol-3arabinosyl-7-rhamnoside. Due to the difference in composition, differentiation of these species will be easy and reliable. Additionally kaempferol-3-rutinoside and quercetin-3-rhamnoside, -xyloside,-glucoside, -galactoside, --l-arabinofuranoside and-rutinoside, and also quercetin-7-rhamnoside and kaempferol-7-glucoside could be detected inP. salicina plums. The total content of flavonol glycosides in the investigated plums ofPrunus domestica (P. salicina) were based on fresh weight about 2500–3340 (7170, 10350) ppm in the leaves and 20–52 (8, 24) ppm in the fruits.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
99.
Evidence for immunologic processes taking part in the pathogenesis of what until now has been called the "essential" form of EPH gestosis is cited. The name of immunogestosis (IG) is introduced. The data of this preliminary study suggest that regular "inoculation" of the female genital tract with allogeneic spermatozoal histocompatibility antigens reduces the incidence of IG. Information about preconceptional sexual habits and contraceptive measures was obtained from 83 selected primigravid patients. Twenty-eight women had mild to moderate IG (Group B);55 did not (Group A). Women in Group B had had less contact with spermatozoa of partners than did women in Group A. Oral contraceptive consumption was less in Group B than in Group A. Women in Group B were younger than women in Group A. All these differences were statistically significant. A new immunoetiologic hypothesis referring to IG, as well as the theoretic and clinical implications arising from it, are discussed. This hypothesis is based on the assumption that spermatozoal histocompatibility antigens can either induce immunologic tolerance or be responsible for the phenomenon of immunologic enhancement in the maternal immunosystem. As the fetus inherits paternal histocompatibility antigens, it is concluded that pre-existing tolerance (or enhancement) exerts an IG-preventive function in a subsequent pregnancy. 相似文献
100.
Levi Valgaerts Andrés Bruhn Markus Mainberger Joachim Weickert 《International Journal of Computer Vision》2012,96(2):212-234
There are two main strategies for solving correspondence problems in computer vision: sparse local feature based approaches
and dense global energy based methods. While sparse feature based methods are often used for estimating the fundamental matrix
by matching a small set of sophistically optimised interest points, dense energy based methods mark the state of the art in
optical flow computation. The goal of our paper is to show that this separation into different application domains is unnecessary
and can be bridged in a natural way. As a first contribution we present a new application of dense optical flow for estimating
the fundamental matrix. Comparing our results with those obtained by feature based techniques we identify cases in which dense
methods have advantages over sparse approaches. Motivated by these promising results we propose, as a second contribution,
a new variational model that recovers the fundamental matrix and the optical flow simultaneously as the minimisers of a single
energy functional. In experiments we show that our coupled approach is able to further improve the estimates of both the fundamental
matrix and the optical flow. Our results prove that dense variational methods can be a serious alternative even in classical
application domains of sparse feature based approaches. 相似文献