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21.
New software standards supporting integration of manufacturing and engineering systems are emerging at a rapid pace. Two groups, the Object Management Group (OMG) and the community producing the Standard for the Exchange of Product Model Data (STEP, formally known as ISO 10303), dominate in the production of standards for manufacturing and engineering industries. Their standards are based on common methods, which can be exploited in developing tests for systems supporting the standards. This paper describes the methods employed and a system that builds on those methods to support the automatic and rapid development of conformance tests for the emerging standards. 相似文献
22.
Kalai Selvan Ramalingam Karmegam Karuppiah Shiamala Devi Ramaiya Vivien How Enoch Kumar Perimal Hassan Sadeghi Naeini Sivasankar Sambasivam Kulanthayan KC Mani 《人机工程学与制造业中的人性因素》2019,29(5):426-434
Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage. 相似文献
23.
Drugs that decrease drug-maintained responding at doses that do not decrease other behaviors in animals may be suitable candidates for development as medications to treat drug abuse in humans. The present study examined whether this effect could be obtained with phentermine, a drug that has been reported to decrease cocaine intake in humans. Rhesus monkeys were trained under multiple fixed-ratio 30-response schedules of food and i.v. cocaine delivery. Phentermine was always given as a slow, i.v. infusion. Acute treatment with phentermine (0.3-10 mg/kg) decreased cocaine-maintained responding at doses that did not decrease, or decreased less, food-maintained responding for each of three unit doses of cocaine (10-100 microg/kg/injection). Subacute treatment with phentermine (3 or 5.6 mg/kg, daily) also decreased cocaine-maintained responding more than food-maintained responding. After subacute treatment was terminated, rates of cocaine-maintained responding generally recovered to levels comparable to those seen during untreated control sessions. Phentermine (0.3-3 mg/kg) did not generally increase responding associated with a very low (1 microg/kg/injection) unit dose of cocaine, suggesting that the decrease in cocaine-maintained responding at higher unit doses was not the result of a leftward shift in the cocaine unit dose-effect function. Phentermine (0.1-3 mg/kg) decreased responding maintained by 1-[2-[bis(4-fluorophenyl) methoxy]ethyl]-4-[3-phenylpropyl] piperazine (GBR 12909) (30 microg/kg/injection) at doses similar to those that decreased food-maintained responding. These results show that phentermine is effective in decreasing cocaine self-administration and suggest that it may be an effective medication for cocaine abuse. 相似文献
24.
Use of poly(tetrafluoroethylene)s as a sample support for the MALDI-TOF analysis of DNA and proteins
A proline rich antigen (PRA), which protects mice against Coccidioides immitis, has been analyzed for differential expression and variation among isolates. Northern blots of RNA from different stages of growth were probed with previously cloned cDNA and showed that mRNA for PRA increased as spherules transformed and matured from mycelia. This pattern corresponds to the relative potency of whole cell vaccines from similar preparations. The PRA gene was then cloned from a genomic library of the Silveira strain of C. immitis and its sequence analyzed. Eight other coccidioidal isolates, selected for diversity in geographic origin and resulting clinical disease, demonstrated heterogeneity in Southern blots and in sequences of polymerase chain reaction products. Silveira differed from other California isolates at 33 of 555 bases, whereas it differed from non-California isolates by <=2 bases. Only one of these substitutions affected protein sequence. Thus, tests or vaccines based on this gene are likely to cover most isolates. 相似文献
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OBJECTIVE: To characterize Seprafilm bioresorbable membrane and assess its efficacy and safety in reducing adhesions. DESIGN: In vitro and animal studies designed to provide precise control of tissue trauma and closely approximate clinically relevant conditions in abdominal surgery. SETTING: Experimental laboratories, USA. SUBJECTS: Experimental animals, principally rats and rabbits. INTERVENTIONS: The rat cecal abrasion or sidewall injury model evaluated the efficacy of seprafilm in the presence of blood and irrigation solutions, in multiple layers, under ischemic conditions, and in adhesion reformation. A rabbit anastomosis model tested the effect of the membrane on wound healing, and a series of challenge tests determined its toxicology, immunogenicity, and biocompatibility. MAIN OUTCOME MEASURES: Incidence and severity of adhesions; mutagenicity; pyrogenicity; irritation effects; systemic toxicity. RESULTS: Seprafilm significantly reduced the number of cecal adhesions (p < 0.001) and the number of animals with severe adhesions (p < 0.001) when compared with nontreated controls, even in the presence of bleeding. The membrane also significantly decreased the number of animals with any adhesions (p < 0.001). Seprafilm maintains efficacy when used with excess irrigation solutions, when layered, and under ischemic conditions. Among rats tested for adhesion reformation, the treated group had a significantly larger proportion of adhesion-free animals than the untreated group, 72% versus 28%, (p = 0.007). Seprafilm did not impair wound healing in anastomosis and is nontoxic, nonmutagenic, nonimmunogenic, nonpyrogenic, nonirritating, and biocompatible. CONCLUSION: Preclinical studies have shown that Seprafilm is safe and effective in reducing postsurgical adhesions. Seprafilm meets the requirements of an ideal barrier and can be a useful adjuvant in abdominal and pelvic surgery. 相似文献
29.
An actin-depolymerizing marine natural product, mycalolide B, and a related compound, kabiramide D, were labeled with biocytin, a biotin derivative, and used to specify target molecules in cultured rat 3Y1 fibroblasts. Mycalolide B exhibited the ability to bind to various intracellular proteins, probably through the Michael addition of a sulfhydryl group to C5 of mycalolide B. However, no intracellular proteins other than actin apparently reacted with biocytinylated kabiramide D, demonstrating that the binding of kabiramide D to actin was highly specific. Cells treated with biocytinylated kabiramide D followed by staining with fluorescein isothiocyanate-conjugated avidin showed that biocytinylated kabiramide D bound to stress fibers composed of F-actin, although the staining intensity was weaker than the fluorescent phalloidin staining. The assay for the binding of kabiramide D to actin, which had previously been treated with other actin-depolymerizing agents, showed that the actin-binding site for kabiramide D was the same as that for bistheonellide A, but not those for latrunculin A and cytochalasin D. 相似文献
30.
HI Pass DJ Mew KC Kranda BK Temeck JS Donington SA Rosenberg 《Canadian Metallurgical Quarterly》1996,61(6):1609-1617
BACKGROUND: A phase I trial was initiated to define the feasibility and safety of single-lung isolation perfusion with tumor necrosis factor-alpha, interferon-gamma, and moderate hyperthermia for patients with unresectable pulmonary metastases. METHODS: Twenty patients with lung metastases (Ewing's, 2; sarcoma, 8; melanoma, 6; other, 4) were considered for single-lung isolation perfusion with 0.3 to 6.0 mg of tumor necrosis factor-alpha and 0.2 mg interferon-gamma delivered through an oxygenated pump circuit. Sixteen perfusions were performed in 15 patients (bilateral in 1). Metastases were completely resected (no single-lung isolation perfusion) in 3 patients, 1 patient had extrapulmonary disease, and one single-lung isolation perfusion was aborted for mechanical reasons. RESULTS: There were no significant changes in systemic arterial blood pressure or cardiac output during perfusion. Systolic pulmonary artery pressure increased with isolation, but returned to pre-single-lung isolation perfusion levels after clamp release. The maximum systemic tumor necrosis factor-alpha level was 8 ng/mL, whereas pump-circuit levels ranged from 200 to 10,976 ng/mL. There were no deaths, and the mean hospitalization period was 9 days (range, 5 to 34 days). A short-term (6 to 9 month) unilateral decrease in perfused nodules was noted in 3 patients (melanoma in 1, adenoid cystic carcinoma in 1, renal cell carcinoma in 1). CONCLUSIONS: Future studies using a combination of biologic modifiers, chemotherapy, and hyperthermia should be pursued to define active cytotoxic agents that will preserve underlying pulmonary function. 相似文献