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排序方式: 共有6148条查询结果,搜索用时 15 毫秒
941.
MJ Mellies AR DeVault K Kassler-Taub ME McGovern HY Pan 《Canadian Metallurgical Quarterly》1993,101(1):97-110
Epidemiologic evidence linking elevated cholesterol concentrations and coronary heart disease (CHD) through the eighth decade of life provides a rationale for lowering cholesterol concentrations to reduce morbidity and mortality from CHD. Pravastatin, a well tolerated HMG CoA reductase inhibitor with a convenient once-daily dosing regimen, has been shown to effectively lower total and low density lipoprotein (LDL) cholesterol. Individual data from more than 1800 hypercholesterolemic patients enrolled in six double-blind, randomized, multicenter studies were pooled and then analyzed to compare the safety and efficacy of pravastatin in the elderly (i.e., patients at least 65 years old) and the non-elderly. In short-term studies (8-16 weeks), response was dose-related and similar in elderly and non-elderly subjects. Pravastatin 20 or 40 mg daily lowered total cholesterol 19-25%, LDL-cholesterol 25-33%, and triglycerides 14-23%; high density lipoprotein (HDL) cholesterol increased 5-10%. During long-term studies, improvements were sustained for more than 24 months in both the non-elderly and elderly. The incidences of adverse drug events and laboratory abnormalities were similar in the elderly and non-elderly patients in all groups (active treatment control with resin, pravastatin alone, or combination therapy). In short-term studies, treatment was discontinued because of adverse events in < 1% of all patients treated with pravastatin (all doses) or placebo. The frequency and profile of adverse events were similar among patients treated with pravastatin or placebo. In long-term studies, treatment was discontinued in 0.4% of patients in the pravastatin group and in 0.3% of the patients in the bile-acid-binding resin group. If drug therapy is warranted, pravastatin appears to be safe and effective for long-term use in elderly patients with hypercholesterolemia. 相似文献
942.
Small-angle X-ray scattering has been employed to study the stability of GP zones in two Al-Zn alloys during fatigue, in order to provide statistically sound information on this process. In a 5.3 at. pct Zn alloy containing l025 zones per m3 with an average diameter of 18 Å, the normally sluggish coarsening was accelerated by fatigue at room temperature by factors of l06 to l07. No coarsening occurred for larger zones, except near a fatigue crack. Reverted samples aged rapidly during fatigue at room temperature, but in a reverted sample of Al-3.5 at. pct Zn cycled at 77 K no appreciable zone growth occurred. Upon warming this sample to room temperature (without any load) rapid clustering took place. These results imply that a vacancy fraction of 10-5 to l0-6 was produced by the fatigue, and this excess vacancy concentration appears to cause the growth during cycling at room temperature. 相似文献
943.
G Richard AR Wright S Harris SZ Doyle B Korge C Mazzanti T Tanaka W Harth OW McBride JG Compton 《Canadian Metallurgical Quarterly》1994,103(5):665-668
Darier's disease (DD) is an autosomal dominant genodermatosis characterized by epidermal acantholysis and dyskeratosis. We have performed genetic linkage studies in 10 families with DD (34 affected) by analyzing 14 polymorphic microsatellite markers. Our results confirm recent reports mapping the DD gene to chromosome 12q23-q24.1. Haplotype analysis of recombinant chromosomes in our families, along with previously reported data, narrow the location of the DD gene to a 5 cM interval flanked by the loci D12S354 and D12S84/D12S105. This localization allowed exclusion of two known genes, PLA2A and PAH, as candidate loci for DD. Three other gene loci (PPP1C, PMCH, PMCA1), mapping in 12q21-q24, remain potential candidates. 相似文献
944.
Empathy was measured by an interview assessing emotions and cognitions in response to videotaped vignettes of persons in affective events and by empathy self-report questionnaires. As hypothesized, empathy was lower among conduct-disordered (CD) than comparison youth and was related inversely to antisocial and aggressive attitudes for all youth tested. Affectively, CD youth (n?=?30) reported fewer concordant emotional responses to vignette persons than did a comparison peer group (n?=?32). Cognitively, CD youth reported fewer correct identifications of vignette persons' emotions, lower mean levels of cognitive attributions for their own responsive emotions, and lower scores on empathy-related cognitive scales. Significant gender differences occurred, with girls scoring higher than boys on empathy questionnaires. Findings are discussed in terms of previous empathy and aggression research, and directions for future study are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
945.
946.
Quality of community drinking water and the occurrence of late adverse pregnancy outcomes 总被引:2,自引:0,他引:2
1. The aim of the study was to investigate whether there were differential effects of three different anti-hypertensive medications (cilazapril, atenolol, nifedipine) on cognitive function. 2. A sub-group of patients participating in a large clinical trial of these three drugs, randomly allocated between the three drug conditions, received cognitive assessment at two points before the commencement of treatment and then after 12 and 24 weeks of treatment. Seventy-six patients began treatment, and 55 completed the full course. 3. Tests of learning and memory were designed specially for the study, with a different but comparable version administered on each assessment occasion, in a fixed order. 4. No significant differences between drug groups were found in any index of learning or memory, at any testing occasion. The results were the same whether or not treatment non-completers were included in the analysis. 相似文献
947.
JK Boeijinga E van Meegen R van den Ende CE Schook AF Cohen 《Canadian Metallurgical Quarterly》1998,38(10):966-970
The objective of this study was to investigate whether the central analgesic tramadol influences the effects of the coumarin anticoagulant phenprocoumon during multiple-dose administration. Nineteen patients receiving long-term anticoagulant therapy who had been in a stable hypothrombinemic state for at least 3 months completed a double-blind, placebo-controlled, crossover study. Tramadol was administered in the usual therapeutic dose of 50 mg three times daily. The average daily phenprocoumon dose was identical for individual patients in both treatment periods. The equivalence ratio (tramadol/placebo) of the international normalized ratio (INR) values was 0.99 (90% confidence interval 0.89-1.10), thus fulfilling predetermined bioequivalence criteria (0.70-1.43). Therefore, tramadol does not affect INR in patients being treated with phenprocoumon. These data suggest a lack of interaction between tramadol and coumarin anticoagulants. 相似文献
948.
RG Kline AJ D'Angelo MH Chen VJ Halpern JR Cohen 《Canadian Metallurgical Quarterly》1998,27(1):81-7; discussion 88
PURPOSE: Laparoscopic surgery decreases postoperative pain, shortens hospital stay, and returns patients to full functional status more quickly than open surgery for a variety of surgical procedures. This study was undertaken to evaluate laparoscopic techniques for application to abdominal aortic aneurysm (AAA) repair. METHODS: Twenty patients who had AAAs that required a tube graft underwent laparoscopically assisted AAA repair. The procedure consisted of transperitoneal laparoscopic dissection of the aneurysm neck and iliac vessels. A standard endoaneurysmorrhaphy was then performed through a minilaparotomy using the port sites for the aortic and iliac clamps. Data included operative times, duration of nasogastric suction, intensive care unit days, and postoperative hospital days. Pulmonary artery catheters and transesophageal echocardiography were used in seven patients. For these patients data included heart rate, pulmonary artery systolic and diastolic pressures, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, and end diastolic area. Data were obtained before induction, during and after insufflation, during aortic cross-clamp, and at the end of the procedure. RESULTS: Laparoscopically assisted AAA repair was completed in 18 of 20 patients. Laparoscopic and total operative times were 1.44 +/- 0.44 and 4.1 +/- 0.92 hours, respectively. Duration of nasogastric suction was 1.3 +/- 0.7 days. Intensive care unit stay was 2.2 +/- 0.9 days. The mean length of hospital stay was 5.8 days excluding three patients who underwent other procedures. There were two minor complications, one major complication (colectomy after colon ischemia), and no deaths. For the eight patients who had intraoperative transesophageal echocardiographic monitoring, no changes were noted in heart rate, pulmonary artery systolic pressure, pulmonary capillary wedge pressure, and cardiac index. Pulmonary artery diastolic pressure and central venous pressure were greatest during insufflation without changes in end-diastolic area. Volume status, as reflected by end-diastolic area and pulmonary capillary wedge pressure, did not change. CONCLUSIONS: Laparoscopically assisted AAA repair is technically challenging but feasible. Potential advantages may be early removal of nasogastric suction, shorter intensive care unit and hospital stays, and prompt return to full functional status. The hemodynamic data obtained from the pulmonary artery catheter and transesophageal echocardiogram during pneumoperitoneum suggest that transesophageal echocardiography may be sufficient for evaluation of volume status along with the added benefit of detection of regional wall motion abnormalities and aortic insufficiency. Further refinement in technique and instrumentation will make total laparoscopic AAA repair a reality. 相似文献
949.
950.