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951.
G.L. Wise 《Journal of The Franklin Institute》1977,303(2):201-207
Mean square continuity of a random process is of considerable theoretical and practical importance. Mean square continuous random processes passed through zero memory non-linearities are considered. Several conditions are given relating to mean square continuity of the output. Bounded zero memory non-linearities are considered with arbitrary random processes as inputs, and conditions on both the zero memory non-linearity and on the random process are examined. Also, general zero memory non-linearities are considered with Gaussian random processes as inputs. 相似文献
952.
Design of detectors for strong mixing signals in strong mixing noise is considered, where a large degree of dependency may occur between the signal and noise. Under the criterion of asymptotic relative efficiency, it is shown that this design reduces to determining the solution of an integral equation, where only knowledge of the second order statistics of the randon processes involved is required. In particular, if the signal is independent of the noise and has nonzero mean, the optimal detector is the same as in the known constant signal case. It is also shown that it is possible to delete several regularity conditions which may be difficult to check in practice in the slightly more restrictive case where the maximal correlation coefficients of the signal and noise tend to zero. 相似文献
953.
T. Malati G. Rajani Kumari I. Dinakar 《Indian journal of clinical biochemistry : IJCB》1995,10(2):72-76
Humoral immune response against PPD derived A60 antigen was evaluated by quantification of serum A60 antibodies in thrity healthy adults not exposed to tuberculosis (Group 1), in twenty seven healthy adults exposed to tuberculosis patients i.e. staff working in wards of tuberculosis hospital for one to thirty years (group 2), in twenty five pulmonary tuberculosis patients admitted to the Institute for Chest Diseases, Hyderabad (Group 3) and in sixty neurotuberculosis patients admitted to Neurosurgery department of our institute (Group 4). Highly significant elevation of A60 antibodies was observed in pulmonary tuberculosis patients (p<0.01) compared to healthy adult groups. A significant elevation in serum was also observed in case of neurotuberculosis group compared to both healthy groups (p<0.01). A test on A60 antibodies in serum gavv a sensitivity of 100%, specificity of 96.6%, positive predictive value of 81% and negative predictive value of 100% for pulmonary tuberculosis, whereas a sensitivity of 58%, positive predictive value of 79% and negative predictive value of 75% were noted for neurotuberculosis patients. Results of A60 antibodies in ten cerebrospinal fluids (CSF) obtained from non tuberculosis patients and thirty two CSF from patients of neurotuberculosis did not show significant elevation of antibodies. However the ninetyfive percentile value of CSF A60 antibodies was higher in neurotuberculosis (7.4 U/ml) group compared to nontuberculous group (3.8 U/ml) and the test showed a good positive predictive value (83%), very low negative predictive value (25%) and low sensitivity (63%). Serum A60 antibody assay appears to be a good serological marker available today for pulmonary tuberculosis and a supportive marker for neurotuberculosis. 相似文献
954.
955.
S.G. Tzafestas 《Journal of The Franklin Institute》1976,302(1):19-36
The buffer design problem is studied for the cases where there exist single- and multiple-input lines with Poisson or Poisson bursts arrivals, periodic block or batch type removals, and binomial feedback.Using traffic intensity σ, block size c, and the feedback probability Pa as parameters, the analytical expressions concerning the average fractional information loss, the channel utilization and the average buffering delay in relation to the buffer length are derived. These relationships are computed for a set of parameter values and are plotted to be used as a basis for the buffer design. The present study should be valuable in designing engineering systems such as time sharing computer systems, information compression systems, computer networks, road traffic simulators, telephone exchanges etc. An illustrative example of a single-input buffer system of the type considered is fully discussed. 相似文献
956.
R. Alli B. Bhunia G. P. Chhotray M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2003,18(1):61-64
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC),
9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial
antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with
DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them
turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively
for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies. 相似文献
957.
M.G. Marieta 《Journal of The Franklin Institute》1976,301(4):317-333
The equations of motion for perfectly mechanical systems which are restricted to satisfy given constraints are derived through the Lagrangian formulation for continuous media. Hamilton's equations for this situation are derived, and the equations for the balance of energy and angular momentum are generated from fundamental principles. These equations are all specialized to the example of a conductor which is vibrating under Aeolian excitation. Various models for the Hamiltonian density and the constraint energy density due to the wind energy input are also discussed. 相似文献
958.
The capacity of newborn infants to smooth-pursuit eye movements in single-target tracking and in optokinetic nystagmus to a moving striped field was examined utilizing DC electrooculography. Smooth-pursuit movements were observed in all infants who were alert during testing, but they occupied less than 15% of viewing time during single-target tracking. The velocity of smooth-pursuit segments in single-target tracking increased linearly to a target velocity of 19 degrees/sec and deteriorated rapidly at faster speeds. No smooth pursuit occurred above 32 degrees/sec in single-target tracking. By contrast, optokinetic nystagmus was observed at all field velocities to 40 degrees/sec, but the speed of the mean slow component increased linearly to 25 degrees/sec and diminished above that field velocity. Infant optokinetic nystagmus differed strikingly from that of adults in that tonic ocular deviation was in the direction of field movement rather than away from it. This feature of neonatal optokinetic nystagmus is consistent with deficient foveal function and suggests that the relatively poor smooth-pursuit performance of newborns may be related to foveal immaturity. 相似文献
959.
Two aspects concerning the production of shapes in handwriting are distinguished in the present paper. The first aspect is indicated by thespatial variability of letters measured across replications. Spatial variability is assumed to reflect the basic spatial noise observed in everyday writing. The second aspect deals with the geometric characteristics of letter shapes, measured by the ratio of the vertical over the horizontal letter size (Y/X-ratio). The main question is whether the geometric characteristics and basic spatial noise originate from a common source. More specifically, we are interested in whether Y/X-ratio as well as spatial variability will alter across changed circumstances, or whether Y/X-ratio will alter without a change in spatial variability. Subjects wrote the simple letter sequencelelele in conditions with and without vision under three scaling conditions requirements (small, normal and large letter sizes). The main results were that geometric aspects of letters altered (Y/X-ratio) under no vision and under the scaling requirement to write in a small format. In contrast, shapes were produced with unchanged spatial variability in all conditions of vision and scaling requirements. The results suggest that alterations of geometric aspects of letters across changed circumstances do not necessarily involve an increase in spatial variability. 相似文献
960.