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991.
BACKGROUND: Bacterial peritonitis is a frequent complication during treatment of end-stage renal failure by continuous ambulatory peritoneal dialysis. Local host defence mechanisms including the secretion of proinflammatory cytokines by peritoneal macrophages are of particular importance in the pathogenesis of infectious complications. LPS-binding protein (LBP) and soluble CD14 (sCD14) are serum factors known to regulate the endotoxin-induced cellular immune response. However, it is still unknown whether LBP and sCD14 are also present in the peritoneal effluent of CAPD patients. METHODS: Using specific immunoassays, we examined the concentration of LBP, sCD14 and the proinflammatory cytokines TNF-alpha, IL-1beta and IL-6 in the dialysis effluents of 31 patients with CAPD-associated peritonitis. Twenty patients without peritonitis served as controls. Intraperitoneal LPS concentrations were determined using the limulus amebocyte lysate assay. RESULTS: Bacterial lipopolysaccharide could be detected in 42% of the infected dialysis effluents. In comparison to controls (0.2 +/- 0.05 microg/ml), LBP was significantly elevated in both gram-negative/LPS-positive (1.03 +/- 0.3 microg/ml) and gram-positive infections (0.5 +/- 0.14 microg/ml) (P<0.05). No significant differences were detected concerning the intraperitoneal sCD14 levels in the three patient groups. Levels of TNF-alpha, IL-1beta and IL-6 were significantly increased in the effluents of patients with bacterial peritonitis compared to noninfected controls. Moreover the respective cytokine concentrations were significantly higher in the gram-negative/LPS-positive compared to the gram-positive bacterial infections (P<0.01). CONCLUSION: Our data demonstrate that LBP is significantly elevated in the dialysis effluents of patients with CAPD-associated peritonitis caused by both gram-negative and gram-positive bacteria and might be used as a marker of intraperitoneal infection. Moreover, our findings support the concept that LBP enhances the effects of LPS on cytokine production by peritoneal macrophages. The function of LBP in gram-positive infection remains to be further elucidated.  相似文献   
992.
PURPOSE: Apoptosis is the final common death pathway of photoreceptors in light-induced retinal degeneration and in several animal models for retinal dystrophy. To date, little is known about gene regulation of apoptosis in the retina. The expression of the immediate early gene c-fos is upregulated concomitant with apoptosis in light-induced photoreceptor degeneration and in the rd mouse, an animal model for inherited retinal degeneration. In a recent study it was shown that c-Fos is essential for light-induced apoptosis of photoreceptors in vivo. To determine whether c-Fos is also involved in the apoptotic pathway of inherited retinal degeneration, rd/rd, c-fos -/- double-mutant mice have been generated. METHODS: Double-mutant mice (rd/rd, c-fos -/-) were crossbred from c-fos+/- mice and rd/rd mice. Their genotype was determined by polymerase chain reaction analysis of genomic DNA. Wild-type control mice and homozygous rd mice were killed at 2-day intervals from postnatal day (P)9 through P21. Double-mutant mice were killed at postnatal days P9, P11, P13, P15, and P21. To determine levels of apoptosis in the retina, eyes were enucleated and processed for light microscopy and in situ nick-end labeling. Total retinal DNA was extracted from isolated retinas for DNA fragmentation analysis. RESULTS: Morphologic, histochemical, and biochemical analyses showed that the time course of apoptosis and the outcome of photoreceptor degeneration in rd/rd, c-fos-/- double-mutant mice was indistinguishable from that in rd mice carrying functional c-fos. CONCLUSIONS: These data suggest that in contrast to its role in light-induced photoreceptor degeneration, c-Fos is not essential for apoptosis in the rd mouse.  相似文献   
993.
The goal of this study was to examine whether data from 3 different measures of communication (i.e., self-report, quasi-observational, and observational) can predict relationship adjustment and stability 1 year later when used conjointly in a sample of 62 young couples. The 3 measures of communication were the Communication Skills Test-Revised (CST-R), the Communication Box (CB), and the Demand/Withdraw Pattern Questionnaire (DWPQ). Through hierarchical multiple regression analyses, results revealed that the CST-R and the DWPQ predict both genders' relationship adjustment 1 year later when used conjointly. Logistic regression analyses revealed that none of the measures of communication significantly predicted relationship stability. In conclusion, the combination of the CST-R and the DWPQ appears to be useful for longitudinally predicting relationship adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
The authors report 3 experiments in which participants were invited to judge the probability of statements of the form if p then q given frequency information about the cases pq, p?q, ?pq, and ?p?q (where ? = not). Three hypotheses were compared: (a) that people equate the probability with that of the material conditional, 1 - P(p?q); (b) that people assign the conditional probability, P(q/p); and (c) that people assign the conjunctive probability P(pq). The experimental evidence allowed rejection of the 1st hypothesis but provided some support for the 2nd and 3rd hypotheses. Individual difference analyses showed that half of the participants used conditional probability and that most of the remaining participants used conjunctive probability as the basis of their judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
Within research on psychoanalysis, the common model of analytic change conceptualizes it as structural reorganization and development of self-analytic function. The present article takes as its point of departure analytic patients who, in follow-up interviews, do not present their experience of change according to this common model. Instead of categorizing analysands as being either successful or unsuccessful cases, the article aims to develop concepts of change that pertain to the experiential domain. Themes in the self experience of three former patients are explored. The data is gathered through follow-up interviews. The interviews were conducted with an analytic approach, which provides data on transference themes. Data from the interviews is not intended to provide empirical support for outcomes, but provides material from which concepts of change can be explored and discussed. The three cases illustrate three distinct psychic dimensions: safety, meaningfulness and sameness. All the cases have in common that they show, as described by Modell (1990), a containing transference in the follow-up interviews. Based on the postulated dimensions of self-experience, and with the view that containing transference is a common theme, it is further argued that, despite showing object-dependency, these informants have undergone an experiential change that is of existential significance. This is a kind of change that, it may be argued, is beyond a structural one; one that may be conceptualized as a precondition for the kind of change assumed by the main analytic model. To develop a self-analytic function, the patient may first need to develop a containing one. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
996.
Balanced scales, that is, scales based on items whose content is either negatively or positively polarized, are often used in the hope of measuring a bipolar construct. Research has shown that usually balanced scales do not yield 1-dimensional measurements. This threatens their construct validity. The authors show how to test bipolarity while accounting for method effects. This is demonstrated on a data set of state and trait anxiety measured with the State-Trait Anxiety Inventory (STAI; C. D. Spielberger, R. L. Gorsuch, R. Lushene, P. R. Vagg, & G. A. Jacobs, 1983) scales. Taking a test–retest perspective, assuming temporally stable method effects, the authors tested the bipolarity of the temporal change through suitable constraints specified in a structural equation model adapted from S. Vautier, R. Steyer, and A. Boomsma (2008). The model fit the data closely, χ2(13, N = 888) = 20.75, p = .07. Thus, the state and trait scales seem to measure bipolar constructs plus temporally stable method effects. Parameter estimates suggest reliable change scores for the state anxiety scale (ρ? = .90) and specific method effects for the state and trait scales of the STAI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
An interleukin-6 (IL-6) response was detected in 81 patients with febrile urinary tract infections (UTIs). Bacteremic patients (n=24) had higher serum IL-6 at inclusion and throughout the first 24 h (P<. 01) and higher urine IL-6 from 6 h after start of therapy (P<.01) than did nonbacteremic patients (n=57). The serum and urine IL-6 responses remained elevated longer in the bacteremic group. Patients with clinical signs of pyelonephritis had higher serum and urine IL-6 concentrations than did other patients in the study population (P=.058, P<.01, respectively). IL-6 high responders had higher temperatures (P<.05) and C-reactive protein levels (P<.05, P<.01) than did low responders. The results demonstrate that IL-6 responses accompany febrile UTIs regardless of bacteremia and that the response reflects disease severity. The results suggest that IL-6 produced in the urinary tract can trigger the systemic host response in the absence of bacteremia.  相似文献   
998.
This study investigated the role of the syllable in visual recognition of French words. The syllable congruency procedure was combined with masked priming in the lexical-decision task (Experiments 1 and 3) and the naming task (Experiment 2). Target words were preceded by a nonword prime sharing the first three letters that either corresponded to the syllable (congruent condition), or not (incongruent condition). When primes were displayed for 67 ms, similar results were found in both the lexical decision and the naming tasks. Consonant-vowel targets such as BA.LANCE were recognised more rapidly in the congruent condition than in the incongruent and control conditions, while consonant-vowel-consonant targets such as BAL.CON were recognised more rapidly in the congruent and incongruent conditions than in the control condition. When a 43-ms SOA was used in the lexical-decision task, no significant priming effect was obtained. The results are discussed in an interactive-activation model incorporating syllable units. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
The effect of finish rolling temperature on the austenite-(γ) to-bainite (α) phase transformation is quantitatively investigated in high-strength C-Mn steels using an alternative crystallographic γ reconstruction procedure, which can be directly applied to experimental electron backscatter diffraction mappings. In particular, the current study aims to clarify the respective contributions of the γ conditioning during the hot rolling and the variant selection during the phase transformation to the inherited texture. The results confirm that the sample finish rolled at the lowest temperature [1102 K (829 °C)] exhibits the sharpest transformation texture. It is shown that this sharp texture is exclusively due to a strong variant selection from parent brass {110} \( \left\langle {1\bar{1}2} \right\rangle \) , S {213} \( \left\langle {\bar{3}\bar{6}4} \right\rangle \) and Goss {110}〈001〉 grains, whereas the variant selection from the copper {112} \( \left\langle {\bar{1}\bar{1}1} \right\rangle \) grains is insensitive to the finish rolling temperature. In addition, a statistical variant selection analysis proves that the habit planes of the selected variants do not systematically correspond to the predicted active γ slip planes using the Taylor model. In contrast, a correlation between the Bain group to which the selected variants belong and the finish rolling temperature is clearly revealed, regardless of the parent orientation. These results are discussed in terms of polygranular accommodation mechanisms, especially in view of the observed development in the hot-rolled samples of high-angle grain boundaries with misorientation axes between 〈111〉γ and 〈110〉γ.  相似文献   
1000.
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