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1.
The aim of this study was to assess the association between the length of maternity leave and the quality of mother-infant interactions; 198 employed mothers of 4-month-old infants were interviewed and videotaped in their homes during a feeding time. Hierarchical multiple regression analyses indicated a direct association between shorter length of leave and more negative affect and behavior in maternal interactions with their infants. Infant and mother stressor/protective variables added significantly in predicting the quality of the mother-infant relationship. There were also significant interaction effects between the length of leave and these variables. Mothers who either reported more depressive symptoms or who perceived their infant as having a more difficult temperament and who had shorter leaves, compared with mothers who had longer leaves, were observed to express less positive affect, sensitivity, and responsiveness in interactions with their infants. The public policy implications of the relation between length of maternity leave, maternal and infant individual differences, and the quality of mother-infant interactions are discussed. 相似文献
2.
S Ziebe B Bech K Petersen AL Mikkelsen A Gabrielsen AN Andersen 《Canadian Metallurgical Quarterly》1998,13(1):178-181
A new oxidative pathway for the degradation of caffeine(1,3,7-Trimethylxanthine, I) by a mixed culture consisting of strains belonging to the genera Klebsiella and Rhodococcus is presented. The mixed culture does not initiate degradation by N-demethylation either complete or partial, but instead carries out oxidation at the C-8 position resulting in the formation of 1,3,7-trimethyluric acid (TMU, II) which further gets degraded to 3,6,8-trimethylallantoin (TMA, III). Both TMU and TMA are hitherto not shown to be formed in the microbial system. Further degradation of TMA (III) by caffeine grown cells yields dimethylurea (VII) as one of the metabolites. Oxygen uptake studies indicated that caffeine(I) grown cells oxidized TMU(II), TMA (III), glyoxalic acid (VI), dimethylurea(VII), and monomethylurea(V), but not monomethyl and dimethyluric acids. The mixed culture does not accept theophylline(1,3-dimethylxanthine), theobromine(3,7-dimethylxanthine), and paraxanthine(1,7-dimethylxanthine) as the carbon source. 相似文献
3.
MH Hennington AM D'Armini JJ Lemasters TM Egan 《Canadian Metallurgical Quarterly》1996,61(7):1009-1014
In an effort to increase the donor pool for lung transplantation (LTX), we have demonstrated the feasibility of LTX from circulation-arrested cadavers in a canine LTX model. We hypothesized that ventilation of the cadaver lung with alveolar gas (20% O2, 5% CO2, balance N2) (AG) would be superior to ventilation with 100% oxygen (O2) after circulatory arrest of the donor. Twelve mongrel dogs were intubated, heparinized and euthanized by pentothal injection and ventilated with AG (n=6) or O2 (n=6). Four hours later, donor animals underwent sternotomy, and the lungs were flushed with cold modified Euro-Collins solution, harvested, and stored inflated in ice slush. Left lung allotransplantation was performed, and recipients were made dependent o n the transplanted lung by occlusion of the contralateral bronchus and pulmonary artery. Recipient animals were ventilated with an FiO2 of 0.4 and followed for 8 hr. Total ischemic time was 7.9 hr for both groups. Pulmonary edema developed in all recipients of AG lungs; one recipient survived the 8-hr observation period with poor oxygenation. In contrast, three of six recipients of O2-ventilated lungs survived for 8-hr with excellent gas exchange. Specimens of donor lungs before and after transplant were evaluated histologically utilizing trypan blue exclusion as an indicator of cell viability. At the time of organ retrieval 4 hr after death, 6% of cells were nonviable in the O2-ventilated cadaver lungs. Circulation-arrested cadaver lungs ventilated with 100% O2 prior to organ retrieval have superior pulmonary function after transplant compared with lungs ventilated with AG. Ventilation of cadaver lungs with AG induces pulmonary injury in this model. retrieval of donor lungs from circulation-arrested cadavers has potential for increasing the pulmonary donor pool. 相似文献
4.
The Department of Veterans Affairs, Social Work Service has designed, developed and implemented the Social Work Information Management System (SWIMS) which provides for the collection and reporting of both administrative and clinical information. This paper describes the implementation of one component of SWIMS, the automated Social Work Data Base/Assessment. The discussion details the implementation process and discusses issues encountered in the implementation of a computerized documentation system. 相似文献
5.
OBJECTIVE: The aim of this study was to demonstrate the MR characteristics of non-Hodgkin lymphoma of the skull base to help in the differential diagnosis of this neoplasm from other conditions. MATERIALS AND METHODS: MR of five patients, 7-64 years old, with pathologically proved lymphomas of the skull base were reviewed. Three cases had primary skull base lesions involving the sphenoid bone and the cavernous sinus. One case with a nasal cavity lesion involving the skull base and one with a relapsing skull base lesion of previously treated tonsillar lymphoma were included. RESULTS: The lesions had signal intensities that were similar to that of gray matter of brain on both T1- and T2-weighted imaging. Bilateral cavernous sinuses were involved with encasement of internal carotid arteries in every case. Postcontrast MR showed homogeneous enhancement of the tumor with dural infiltration along the planum sphenoidale, clivus, or tentorium. The clivus was destroyed or replaced by tumors in adult cases but in two children the clivus was preserved with intact sphenooccipital synchondrosis. In one case the tumor extended to the extracranial portion through the jugular foramen. CONCLUSION: The MR findings of a permeative lesion of the skull base, invasion of the cavernous sinus without arterial narrowing, infiltration along the dural surface, and an iso- or hypointensity with brain on T2-weighted imaging should suggest lymphoma. 相似文献
6.
Petroleum asphaltenes have been precipitated in solvent mixtures of n-heptane and toluene at various temperatures, likewise n-heptane asphaltenes have been dissolved in under similar conditions. This give added evidence to apparent hysteresis phenomenon between the two processes. The Asphaltenes have been characterized showing that although data is scattered convergence to certain structural parameters as incipient flocculation is approached. The asphaltenes are seen to consist of an associating and a non-associating part. The solubility of asphaltenes has been correlated/modelled using the Flory-Huggins equation using two different terms for the Flory parameter. A process for evaluation of best choice of solubility parameter and molar volume for the asphaltenes is proposed. Dissolution processes are seen to be best fitted by the equations. Based on these findings the asphaltenes are proposed to be formed by a colloidal and a true solution part. 相似文献
7.
8.
Cells in the dorsal division of the medial superior temporal area (MSTd) have large receptive fields and respond to expansion/contraction, rotation, and translation motions. These same motions are generated as we move through the environment, leading investigators to suggest that area MSTd analyzes the optical flow. One influential idea suggests that navigation is achieved by decomposing the optical flow into the separate and discrete channels mentioned above, that is, expansion/contraction, rotation, and translation. We directly tested whether MSTd neurons perform such a decomposition by examining whether there are cells that are preferentially tuned to intermediate spiral motions, which combine both expansion/contraction and rotation components. The finding that many cells in MSTd are preferentially selective for spiral motions indicates that this simple three-channel decomposition hypothesis for MSTd does not appear to be correct. Instead, there is a continuum of patterns to which MSTd cells are selective. In addition, we find that MSTd cells maintain their selectivity when stimuli are moved to different locations in their large receptive fields. This position invariance indicates that MSTd cells selective for expansion cannot give precise information about the retinal location of the focus of expansion. Thus, individual MSTd neurons cannot code, in a precise fashion, the direction of heading by using the location of the focus of expansion. The only way this navigational information could be accurately derived from MSTd is through the use of a coarse, population encoding. Positional invariance and selectivity for a wide array of stimuli suggest that MSTd neurons encode patterns of motion per se, regardless of whether these motions are generated by moving objects or by motion induced by observer locomotion. 相似文献
9.
Determined the specific type of sexual functioning deficits and the relationship between global sexual satisfaction and adjustment in 2 related life areas (marital relationship and body image) for 2 groups of cancer patients at high risk for sexual difficulties. The 2 groups included 16 27–67 yr old females with Stage 2 breast cancer and 16 31–65 yr old females with gynecologic cancer. These Ss were compared to 16 healthy female outpatients (controls). Measures included the Sexual Activities scale from the Derogatis Sexual Functioning Inventory, a modified version of the Dyadic Assessment Scale (marital adjustment), a global sexual evaluation, and a body-image scale. Analyses revealed that the aspects of sexual functioning for breast-cancer and gynecologic-cancer Ss that differed from those of controls were the frequency of sexual behaviors and the level of sexual arousal. Whereas Ss' evaluations of their current sexual life had no relationship to their marital-adjustment ratings, analyses suggested that body-image disruption may be a prevalent problem for gynecologic cancer patients. Data suggest that cancer diagnosis and treatment are instrumental in producing reductions in sexual activity and arousability. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
MD Goldberg JR Canvin P Freestone C Andersen D Laoudj PH Williams IB Holland V Norris 《Canadian Metallurgical Quarterly》1997,79(6):315-322
In the bacterium Escherichia coli, H-NS-(H1, H1a) is a heat-stable protein with a molecular mass of 15.5 kDa involved in nucleoid organisation and gene regulation linked to certain signal transduction pathways. We have shown that, following addition of preparations of everted inner membrane vesicles, heat-stable cleavage products of approximately 10 kDa of H-NS are formed in vitro from newly synthesised, radio-labelled H-NS and from purified H-NS. The 15.5 kDa protein and its cleavage products were also recovered from a minicell system. These results raised the possibility that cleavage of H-NS is physiologically significant. However, the cleavage of H-NS observed appears to occur during cell breakage and to depend on the method of protein extraction and the presence of the outer membrane protease, OmpT. Nevertheless, the results indicate that H-NS may contain at least two separate domains with cleavage occurring between these domains at a preferred OmpT site. Failure to take account of H-NS cleavage in sample preparation and analysis can lead to serious underestimation of H-NS levels. 相似文献