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951.
This paper explores two dimensions of internalized object relations in borderline and schizophrenic patients using Rorschach scales. A thematic and a structural Rorschach measure of object relations is applied to the Rorschachs of two borderline groups (an infantile personality group and an obsessive-paranoid group) and a schizophrenic group. The findings suggest the value of both a multidimensional definition of internalized object relations and the use of such an approach to clarifying the diagnostic concept of borderline personality disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
952.
953.
UA Zifko PJ Slomka RH Reid GB Young H Remtulla CF Bolton 《Canadian Metallurgical Quarterly》1996,139(2):197-202
Parasitic third-stage larvae of the sheep abomasal nematode Haemonchus contortus develop and molt in vitro to the fourth stage (L4) in 48-72 hr, at which time they begin feeding. Coincident with the third molt, larvae begin to secrete significant amounts of protein into culture fluids, including a zinc metalloproteinase. This culture-derived zinc metalloproteinase differs from a previously described metalloproteinase from infective third-stage larvae (L3[2M]), which mediates the ecdysis process. These differences include time of expression, molecular mass, and substrate specificity. The purified proteinase, from cultures of L4, has a molecular weight of approximately 46 kDa, functions as an endopeptidase, and digests several native proteins of host origin including fibrinogen and fibronectin. 相似文献
954.
The major inhibitory components obtained after fractionation of an aqueous extract of field-grown sorghum (Sorghumbicolorcv. Bird-a-boo) herbage were quantified in terms of biological potency by indexing three aspects of cumulative cress (Lepidium sativum cv. Curlycress) seed germination. The inhibitory potential expressed in the crude aqueous extract reflected a complex interaction of numerous individual components of diverse chemical compositions and potencies. Some of these inhibitory components included chemical classes not previously associated with herbage phytotoxicity. 相似文献
955.
956.
ND DeWitt CF dos Santos KE Allen CW Slayman 《Canadian Metallurgical Quarterly》1998,273(34):21744-21751
Mutations at the phosphorylation site (Asp-378) of the yeast plasma-membrane H+-ATPase have been shown previously to cause misfolding of the ATPase, preventing normal movement along the secretory pathway; Asp-378 mutations also block the biogenesis of co-expressed wild-type ATPase and lead to a dominant lethal phenotype. To ask whether these defects are specific for Asp-378 or whether the phosphorylation region as a whole is involved, alanine-scanning mutagenesis has been carried out to examine the role of 11 conserved residues flanking Asp-378. In the sec6-4 expression system (Nakamoto, R. K., Rao, R., and Slayman, C. W. (1991) J. Biol. Chem. 266, 7940-7949), the mutant ATPases displayed varying abilities to reach the secretory vesicles that deliver plasma-membrane proteins to the cell surface. Indirect immunofluorescence of intact cells also gave evidence for a spectrum of behavior, ranging from mutant ATPases completely arrested (D378A, K379A, T380A, and T384A) or partially arrested in the endoplasmic reticulum to those that reached the plasma membrane in normal amounts (C376A, S377A, and G381A). Although the extent of ER retention varied among the mutants, the endoplasmic reticulum appeared to be the only secretory compartment in which the mutant ATPases accumulated. All of the mutant proteins that localized either partially or fully to the ER were also malfolded based on their abnormal sensitivity to trypsin. Among them, the severely affected mutants had a dominant lethal phenotype, and even the intermediate mutants caused a visible slowing of growth when co-expressed with wild-type ATPase. The effects on growth could be traced to the trapping of the wild-type enzyme with the mutant enzyme in the ER, as visualized by double label immunofluorescence. Taken together, the results indicate that the residues surrounding Asp-378 are critically important for ATPase maturation and transport to the cell surface. 相似文献
957.
DL Clemans CF Marrs M Patel M Duncan JR Gilsdorf 《Canadian Metallurgical Quarterly》1998,66(2):656-663
Adherence of Haemophilus influenzae to epithelial cells plays a central role in colonization and is the first step in infection with this organism. Pili, which are large polymorphic surface proteins, have been shown to mediate the binding of H. influenzae to cells of the human respiratory tract. Earlier experiments have demonstrated that the major epitopes of H. influenzae pili are highly conformational and immunologically heterogenous; their subunit pilins are, however, immunologically homogenous. To define the extent of structural variation in pilins, which polymerize to form pili, the pilin genes (hifA) of 26 type a to f and 16 nontypeable strains of H. influenzae were amplified by PCR and subjected to restriction fragment length polymorphism (RFLP) analysis with AluI and RsaI. Six different RFLP patterns were identified. Four further RFLP patterns were identified from published hifA sequences from five nontypeable H. influenzae strains. Two patterns contained only nontypeable isolates; one of these contained H. influenzae biotype aegyptius strains F3031 and F3037. Another pattern contained predominantly H. influenzae type f strains. All other patterns were displayed by a variety of capsular and noncapsular types. Sequence analysis of selected hifA genes confirmed the 10 RFLP patterns and showed strong identity among representatives displaying the same RFLP patterns. In addition, the immunologic reactivity of pili with antipilus antisera correlated with the groupings of strains based on hifA RFLP patterns. Those strains that show greater reactivity with antiserum directed against H. influenzae type b strain M43 pili tend to fall into one RFLP pattern (pattern 3); while those strains that show equal or greater reactivity with antiserum directed against H. influenzae type b strain Eagan pili tend to fall in a different RFLP pattern (pattern 1). Sequence analysis of representative HifA pilins from typeable and nontypeable H. influenzae identified several highly conserved regions that play a role in bacterial pilus assembly and other regions with considerable amino acid heterogeneity. These regions of HifA amino acid sequence heterogeneity may explain the immunologic diversity seen in intact pili. 相似文献
958.
959.
We develop two applications of middle-out reasoning in inductive proofs: logic program synthesis and the selection of induction
schemes. Middle-out reasoning as part of proof planning was first suggested by Bundy et al. Middle-out reasoning uses variables
to represent unknown terms and formulae. Unification instantiates the variables in the subsequent planning, while proof planning
provides the necessary search control.
Middle-out reasoning is used for synthesis by planning the verification of an unknown logic program: The program body is represented
with a meta-variable. The planning results both in an instantiation of the program body and a plan for the verification of
that program. If the plan executes successfully, the synthesized program is partially correct and complete.
Middle-out reasoning is also used to select induction schemes. Finding an appropriate induction scheme during synthesis is
difficult because the recursion of the program, which is unknown at the outset, determines the induction in the proof. In
middle-out induction, we set up a schematic step case by representing the constructors that are applied to induction variables
with meta-variables. Once the step case is complete, the instantiated variables correspond to an induction appropriate to
the recursion of the program.
We have implemented these techniques as an extension of the proof planning system CL
A
M, called Periwinkle, and synthesized a variaety of programs fully automatically.
Supported by the Swiss National Science Foundation and ARC Project BC/DAAD Grant 438. The work described in this paper was
carried out while the first author was at the Department of Artificial Intelligence of the University of Edinburgh.
Supported by the German Ministry for Research and Technology (BMFT) under grant ITS 9102 and ARC Project BC/DAAD Grant 438.
Responsibility for the contents of this publication lies with the authors.
Supported by SERC grant GR/J/80702, ESPRIT BRP grant 6810, ESPRIT BRP grant EC-US 019-76094, and ARC Project BC/DAAD Grant
438. 相似文献
960.
An efficient monoclonal aldolase antibody that proceeds by an enamine mechanism was generated by reactive immunization. Here, this catalyst has been used in the total synthesis of epothilones A (1) and C (3). The starting materials for the synthesis of these molecules have been obtained by using antibody-catalyzed aldol and retro-aldol reactions. These precursors were then converted to epothilones A (1) and C (3) to complete the total synthesis. 相似文献