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941.
KC Marcus HE Grier RC Shamberger MC Gebhardt A Perez-Atayde B Silver NJ Tarbell 《Canadian Metallurgical Quarterly》1997,131(4):603-607
PURPOSE: To evaluate the disease-free and overall survival of pediatric patients with nonrhabdomyosarcoma soft-tissue sarcomas. METHODS: We retrospectively analyzed the records of 67 pediatric patients with a diagnosis of nonrhabdomyosarcoma soft tissue sarcoma treated with curative intent between 1970 and 1992. Median follow-up time for the 52 survivors was 120 months (range, 7 to 277 months). Fifty-nine patients received external beam radiotherapy, in a median dose of 5400 cGy (range, 1800 to 6660 cGy.) All patients underwent an initial surgical procedure. Eighteen patients had gross residual disease, and 15 had gross total excision with microscopic residual disease or positive margins. Adjuvant chemotherapy was administered to 44 patients (65%). RESULTS: The actuarial 10-year freedom from progression or recurrence and overall survival rates were 76% and 75%, and the 20-year rates were the same. Of 18 patients with gross residual disease, 9 (50%) had local progression and 6 died of local-only disease. By contrast, only one patient with microscopic residual disease who received postoperative radiotherapy had a local recurrence. The disease-free survival rate also correlated with histologic grade. CONCLUSIONS: As with adult soft tissue sarcomas, gross residual disease predicts local failure. Our results suggest that pediatric patients with soft tissue sarcomas treated with surgery and postoperative radiotherapy generally have a favorable overall survival rate. 相似文献
942.
Examined retention of 2nd-language skills of 128 9th graders after a 9-mo absence of instruction in French as a 2nd language. Students were tested 3 times: at the beginning of the term, at the end of the semester, and 9 mo later. Ss perceived significant losses in speaking, reading, writing, and understanding French 9 mo after training ended. Written production skills also declined significantly, though recognition skills did not. Ss' attitudes toward the 2nd-language community and the learning situation also declined significantly, while their anxiety about using French increased. Few of the correlations of aptitude, attitude, motivation, or language anxiety with proficiency change scores were significant, although the correlations were substantial and stable from pretest to posttest. A casual model linking these measures to objective indices of French achievement explained the correlation among the variables. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
943.
NJ Dovichi 《Canadian Metallurgical Quarterly》1997,18(12-13):2393-2399
Capillary electrophoresis has been under development for DNA sequencing since 1990. This development has traveled down two parallel tracks. The first track studied the details of DNA separation by gel electrophoresis. Early work stressed rapid separations at high electric fields, which reached the extreme of a 3.5 min sequencing run at 1200 V/cm. While fast separations are useful in clinical resequencing applications for mutation detection, long read-length is important in genomic sequencing. Unfortunately, sequence read-length degrades as electric field and sequencing speed increases; this tradeoff between read-length and sequencing speed appears to be a fundamental result of the physics of DNA separations in a polymer. The longest sequence sequencing read-lengths have been obtained at modest electric fields, high temperature, and with low concentration noncrosslinked polymers. In parallel with our understanding of DNA separations, the second track of DNA sequencing development considered the design of large-scale capillary instruments, wherein hundreds of DNA samples can be sequenced in parallel. Real-world application of these very high throughput capillary electrophoresis systems will require significant investment in sample preparation technology. 相似文献
944.
Research has been carried out with the aim of better understanding the relevant properties of materials to be used in a new self‐healing cementitious composite material system. In a previous study, the buildup of stress in a heat‐activated restrained predrawn poly(ethylene terephthalate) (PET) specimen was investigated. In the current study, the long‐term stress relaxation behavior of such a restrained specimen has been explored so that its potential for use in the new material system can be better understood. The work includes an experimental study in which the stress in a number of PET specimens, restrained against longitudinal shrinkage, was measured during the initial heat activation and cooling phases, and then monitored for a further 6 months. These data were used to quantify the stress relaxation of the specimen and to inform the development of a new one‐dimensional numerical model to simulate the thermomechanical behavior of this material. This model is shown to be able to reproduce the observed short‐ and long‐term experimental behavior with good accuracy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41208. 相似文献
945.
OBJECTIVES: Alterations of mechanosensitive thresholds occur in a subset of patients with functional dyspepsia and irritable bowel syndrome (IBS). However, symptoms associated with these two conditions frequently overlap. It is not known how often subjects with and without symptom overlap have abnormal intestinal sensory thresholds. Our objective was to assess the pattern of symptoms and small intestinal sensory thresholds in patients with functional disorders. METHODS: We studied 157 consecutive patients who had undergone extensive diagnostic work-up to exclude organic disease. Abdominal symptoms were assessed with a validated instrument, and patients were categorized as having functional dyspepsia, IBS, or both. With a barostat device, we tested small intestinal mechanosensitive function in 22 randomly selected patients from this population (with functional dyspepsia, IBS, or both) and 22 healthy controls. RESULTS: Sixty-seven patients (43%) reported simultaneous symptoms of functional dyspepsia and IBS, whereas symptoms of functional dyspepsia or of IBS alone occurred in 68 (43%) and 22 (14%) patients, respectively. Thresholds for first perception and maximum tolerated pressure (mm Hg +/-SD) were significantly lower in patients (21.0 +/- 2.0 and 31.0 +/- 1.0) than in controls (32.0 +/- 1.8 and 39.0 +/- 0.9, p < 0.001). However, thresholds for first perception and maximum tolerated pressure did not differ (p > 0.6) in patients with functional dyspepsia alone (20.1 +/- 3.2 and 28.9 +/- 2.5, n = 9), functional dyspepsia and concomitant IBS (19.9 +/- 2.7 and 30.7 +/- 2.2, n = 8), or IBS alone (23.5 +/- 2.3 and 33.3 +/- 3.0, n = 5). CONCLUSIONS: Small intestinal mechanosensitive pathways are disturbed in patients with functional dyspepsia and IBS. Differences in the pattern and localization of symptoms probably do not reflect differences in small intestinal sensory thresholds. Functional dyspepsia and IBS cannot be distinguished on the basis of altered small intestinal sensory thresholds. 相似文献
946.
947.
The visual motion aftereffect (MAE) typically occurs when stationary contours are presented to a retinal region that has previously been exposed to motion. It can also be generated following observation of a stationary grating when two gratings (above and below it) move laterally: the surrounding gratings induce motion in the opposite direction in the central one. Following adaptation, the centre appears to move in the direction opposite to the previously induced motion, but little or no MAE is visible in the surround gratings [Swanston & Wade (1992) Perception, 21, 569-582]. The stimulus conditions that generate the MAE from induced motion were examined in five experiments. It was found that: the central MAE occurs when tested with stationary centre and surround gratings following adaptation to surround motion alone (Expt 1); no MAEs in either the centre or surround can be measured when the test stimulus is the centre alone or the surround alone (Expt 2); the maximum MAE in the central grating occurs when the same surround region is adapted and tested (Expt 3); the duration of the MAE is dependent upon the spatial frequency of the surround but not the centre (Expt 4); MAEs can be observed in the surround gratings when they are themselves surrounded by stationary gratings during test (Expt 5). It is concluded that the linear MAE occurs as a consequence of adapting restricted retinal regions to motion but it can only be expressed when nonadapted regions are also tested. 相似文献
948.
949.
The abundance and organization of polypeptides associated with antigens of the Rh blood group system
B Gardner DJ Anstee WJ Mawby MJ Tanner AE von dem Borne 《Canadian Metallurgical Quarterly》1991,1(2):77-85
Twelve murine monoclonal antibodies, which react with human red cells of common Rh phenotype but give weak or negative reactions with Rh null erythrocytes, were used in quantitative binding assays and competitive binding assays to investigate the abundance and organization of polypeptides involved in the expression of antigens of the Rh blood group system. Antibodies of the R6A-type (R6A, BRIC-69, BRIC-207) and the 2D10-type (MB-2D10, LA18.18, LA23.40) recognize related structures and 100,000-200,000 molecules of each antibody bind maximally to erythrocytes of common Rh phenotype. Antibodies of the BRIC-125 type (BRICs 32, 122, 125, 126, 168, 211) recognize structures that are unrelated to those recognized by R6A-type and 2D10-type antibodies and between 10,000 and 50,000 antibody molecules bind maximally to erythrocytes of the common Rh phenotype. The binding of antibodies of the R6A-type and the 2D10-type, but not of antibodies of the BRIC-125-type could be partially inhibited by human anti-D antibodies (polyclonal and monoclonal) and a murine anti-e-like antibody. These results are consistent with evidence (Moore & Green 1987; Avent et al., 1988b) that the Rh blood group antigens are associated with a complex that comprises two groups of related polypeptides of M(r) 30,000 and M(r) 35,000-100,000, respectively, and suggest that there are 1-2 x 10(5) copies of this complex per erythrocyte. The polypeptide recognized by antibodies of the BRIC-125 type is likely to be associated with this complex. 相似文献
950.
E Dragunsky R Taffs Y Chernokhvostova T Nomura K Hioki D Gardner L Norwood I Levenbook 《Canadian Metallurgical Quarterly》1996,24(2):77-86
Two poliovirus-susceptible transgenic mouse (Tg PVR) strains, Tg1 and Tg21, were compared with the monkey test for their sensitivity to neurovirulence of live oral poliovirus vaccine (OPV). Intracerebral (i.c.) and intraspinal (i.s.) routes of inoculation were investigated to determine the most suitable combination of mouse strain and route. Evaluation of the mouse tests was performed using several indicators; clinical score and failure time were selected as the most efficient. Tg1 and Tg21 mice inoculated i.s. with type 2, and Tg21 mice inoculated i.s. with type 3 OPV were determined to be the most appropriate systems, whereas they are shown not to be suitable for type 1 OPV. The sensitivity of each of the two mouse models was at least equal to that of the monkey test, suggesting that these mouse systems might be considered as a potential replacement for the monkey test of OPV. However, more data are needed to establish regulatory criteria of acceptability for vaccine lots tested in Tg PVR mice. This is the first study conducted with Tg PVR mice with all three types of poliovirus vaccine preparations. 相似文献