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91.
There seems to be a resistance of patients and physicians towards aggressive diagnostic evaluation of the symptoms of lung cancer in young people. We here review nine series of young patients with primary lung cancer. Patients below 40 years of age represent between 1.2 and 5% of the total lung cancer population. The distribution of sex and histopathologic findings is different, there being more women, fewer cases of squamous cell and more cases of small anaplastic and adenocarcinoma in the young group. Between 87 and 96% are smokers. There is a delay from the debut of symptoms to the first contact with a general physician of 2.4 to 10.8 months. There is a wide variation concerning tendency to operate with a frequency of curative resection of between 15 and 57%. Based on the survival of young patients who are treated by curative surgical resection, the outcome of surgical treatment for young patients does not differ from the general experience concerning resection in patients of all ages. Young patients who are found inoperable have worse survival than the older patients. Seventy to 90%, more than in the group of patients of all ages, have stadium II or III at the time of diagnosis. In conclusion, physicians should be aggressive with respect to the diagnostic evaluation even of young patients with symptoms suggestive of lung cancer. 相似文献
92.
93.
Stubenrauch C.F. Newell A.C. Repjar A.G. MacReynolds K. Tamura D.T. Larsen F.H. Lemanczyk J. Behe R. Portier G. Zehren J.C. Hollmann H. Hunter J.D. Gentle D.G. de Vreede J.P.M. 《Antennas and Propagation, IEEE Transactions on》1996,44(10):1367-1374
An international intercomparison of horn gain and polarization measurements at X-band has previously been completed. There were seven participating laboratories with the National Institute of Standards and Technology serving as the pilot laboratory. Two X-band pyramidal standard gain horns with a nominal gain of 22 dB served as the traveling standards. Quantities measured included on-axis fixed frequency gain at 8, 10, and 12 GHz, swept frequency gain between 8-12 GHz and polarization characteristics at the three fixed frequencies. All laboratories performed the fixed frequency-gain measurements. The swept-frequency and polarization measurements were optional, with four laboratories performing swept-frequency measurements and three laboratories measuring polarization. The results of the gain measurements generally agreed within the reported uncertainties which were of the order of 0.1 dB or less 相似文献
94.
DA Gilbert FE Silverstein RL Protell MB Dennis C Gulacsik DC Auth 《Canadian Metallurgical Quarterly》1980,1(2):177-182
During the past five years we have evaluated argon laser photocoagulation in various canine models of upper gastrointestinal hemorrhage. In gastric erosions, the eight-watt argon laser was uniformly effective in stopping bleeding. In our standard acute ulcer model the seven-watt argon laser was effective in stopping bleeding from most ulcers and only occasionally produced deep injury. With the addition of a jet of CO2 exiting the laser catheter coaxial to the laser beam, the argon laser was 100% effective and no deep injury resulted. The application of the argon laser in a more physiologic canine bleeding model using a single bleeding vessel in an ulcer base is currently under study. The development of improved animal models of gastrointestinal bleeding should contribute to the identification of effective and safe endoscopic hemostatic methods. 相似文献
95.
An attitude questionnaire, for use with the personnel of a Great Lakes shipping concern, was constructed using rational judgments to assign items to areas of the questionnaire. The areas were nominally those suggested as invariant by Wherry. The degree of agreement between the rational sort and the areas named from the invariant factor characteristics was determined. Attitude characteristics of the surveyed group as well as mechanical and response artifacts are suggested as providing partial explanations of the differences found. Items identified as critical through use of several item indices are compared to evaluate index utility. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
97.
As previously reported, pancreatic acinar cell necrosis and inflammation develop in mice a few hours after one intraperitoneal injection of foreign serum. However, sublethally injured acinar cells exhibited notable increases in both zymogen granule numbers and amylase activity, observed within 3 hours and increasing with time. These two changes were coupled with a progressive decrease in the secretory response to pilocarpine and were preceded by significant disturbances in pancreatic tissue concentrations of sodium and potassium. We conclude that (1) the granule increase results from an induced disturbance of the granule exocytosis mechanism while granule formation continues and, therefore, (2) the granule secretory process is more sensitive to the serum injury mechanism than is the zymogen synthesis process. Although the granule increases developed in acinar cells throughout most of the nonnecrotic gland and persisted for at least 24 hours, acinar cell necrosis was maximal in extent--approximately 25% of the gland in severest form--by 12 to 15 hours. We conclude, therefore, that the increase in granules is neither the primary determinant nor initiator of acinar cell death. The latter is likely caused by disturbed plasma membrane functions, sufficient in some cells to result in lethal changes in ion and fluid composition. The injury mechanism, which permits granule formation to go on in the face of impaired granule exocytosis, is yet to be worked out. The possibilities are discussed in relationship to the reactivity of foreign sera for target cell plasma membranes. 相似文献
98.
CVD growth conditions, particularly growth temperature and partial pressures of the reactant gases, strongly affect the growth
characteristics and properties of GaAs0.6P0.4 epitaxial layers grown on GaAs substrates. For LED’s the most important properties of the material are B/J (brightness per
unit current density) and surface morphology. This paper presents the results of a systematic study of the effect of temperature
and reactant gas partial pressure (at a fixed III/V ratio) on B/J, surface morphology, growth rate, impurity doping and layer
composition. Growth conditions which yield the optimum properties for LED’s are determined. The results are interpreted on
the basis of kinetic and thermodynamic mechanisms controlling the growth process under various growth conditions. At constant
temperature and constant III/V ratio, increasing the partial pressures causes the growth process to change from mass transport
limited, where the growth rate increases with increasing partial pressures, to kinetically limited, where the growth rate
is independent of partial pressures. Good morphology layers are obtained over a range of partial pressures around the transition
from mass transport limited to kinetically limited growth. The B/J peaks at a value of partial pressure in the kinetically
limited regime at which good morphology layers are obtained. Although B/J increases with increasing growth rate in the mass
transport regime, the maximum B/J occurs in the region where growth rate is independent of partial pressures so that growth
rate alone is not sufficient to determine B/J. In contrast to the “parabolic≓ dependence of growth rate on growth temperature,
caused by the transition from the mass transport regime to the kinetic regime, the relative incorporation of As, P, and Te
varies with temperature in the manner predicted from thermodynamics in both regimes. This behavior is consistent with the
growth rate in the kinetic regime being limited by the desorption of chlorine atoms from the growth surface, with the reaction
of As, P, and Te with the Ga proceeding thermodynamically at all temperatures. 相似文献
99.
Edward W. Larsen 《Progress in Nuclear Energy》1981,8(2-3):203-214
A substantial amount of recent work has been done in applying singular eigenfunctions to transport problems whose cross sections vary continuously with position. In this article we survey the methodology and results so far obtained, and we briefly discuss some of the many open questions. 相似文献
100.
FE Dougherty 《Canadian Metallurgical Quarterly》1976,44(6):889-897
Exp I (a) established outcome criteria using evaluation ratings from 24 patient-therapist dyads; (b) produced 11 quantifiable personality predictors through factor analysis of 18 therapists' and 65 patients' scores on a test battery (including the MMPI and the Omnibus Personality Inventory); (c) identified 3 typological categories of both patients and therapists homogeneous with respect to these variables and 2 groups of therapists each homogeneous with respect to therapeutic approach; and (d) derived 5 regression equations predicting outcome for each patient and therapist group. Exp II, with 24 therapists and 56 patients who were university students or their spouses, utilized these findings to form 2 experimental dyad groups for which (a) optimal or (b) minimal therapist outcome ratings were predicted, and 2 control groups each for both optimal and deterioration matches that controlled for patient type and therapist type, respectively. Results indicate significant differences between mean outcome in the comparison of the deterioration-matched group both with its control and the optimally matched group. Findings demonstrate the usefulness of carefully planned matching techniques. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献