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91.
92.
JE Meissner 《Canadian Metallurgical Quarterly》1996,26(1):52-53
An audit of the clinical use of EEG in mentally handicapped patients was performed over a three-year period. EEG requests seemed inappropriate in more than one-quarter of cases. Changes in clinical practice during the 10 months following presentation of these audit results were examined. There was a marked reduction in EEG requests, which were subsequently used in a more cost-effective and clinically appropriate way. There was also a reduction in the time taken to process requests. 相似文献
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JB Laursen A Mülsch S Boesgaard P Mordvintcev S Trautner N Gruhn JE Nielsen-Kudsk R Busse J Aldershvile 《Canadian Metallurgical Quarterly》1996,94(9):2241-2247
BACKGROUND: In vitro data suggest that reduced bioconversion of nitroglycerin (NTG) to nitric oxide (NO) contributes to the development of vascular and hemodynamic tolerance to NTG. We examined the in vivo validity of this hypothesis by measuring NTG-derived NO formation by in vivo spin-trapping of NO in vascular tissues from nitrate-tolerant and -nontolerant rats. METHODS AND RESULTS: Five groups (n = 6 to 8 each) of conscious chronically catheterized rats received NTG (0.2 or 1 mg/h IV) for 72 hours (nitrate-tolerant groups). Four other groups received either NTG vehicle (placebo, for 72 hours) or were left untreated (control). Nitrate tolerance was substantiated by a reduced (55% to 85%) hypotensive response to NTG in vivo and a reduced relaxation to NTG in isolated aortic rings. NTG-derived NO formation in aorta, vena cava, heart, and liver was measured as NOFe(DETC)2 and NO-heme complexes formed in vivo during 35 minutes combined with ex vivo cryogenic electron spin resonance spectroscopy. NO formation was significantly (P < .05) increased in all tissues in nitrate-tolerant rats in an NTG dose-dependent manner. Furthermore, the amount of NO formed from a bolus dose of NTG (6.5 mg/kg over 20 minutes) was similar in nitrate-tolerant and -nontolerant rats. CONCLUSIONS: The results suggest that vascular and hemodynamic NTG tolerance occurs despite high and similar rates of NO formation by NTG in tolerant and nontolerant target tissues. This finding is compatible with the assumption that reduced biological activity of NO, rather than reduced bioconversion of NTG to NO, contributes to in vivo development of nitrate tolerance. 相似文献
95.
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JM Lablanche EP McFadden N Meneveau JR Lusson B Bertrand JP Metzger V Legrand G Grollier C Macaya B de Bruyne A Vahanian A Grentzinger C Masquet JE Wolf G Tobelem S Fontecave A Vacheron P d'Azemar ME Bertrand 《Canadian Metallurgical Quarterly》1997,96(10):3396-3402
BACKGROUND: Experimental studies suggest that the antiproliferative effect of heparin after arterial injury is maximized by pretreatment. No previous studies of restenosis have used a pretreatment strategy. We designed this study to determine whether treatment with nadroparin, a low-molecular-weight heparin, started 3 days before the procedure and continued for 3 months, affected angiographic restenosis or clinical outcome after coronary angioplasty. METHODS AND RESULTS: In a prospective multicenter, double-blind, randomized trial, elective coronary angioplasty was performed on 354 patients who were treated with daily subcutaneous nadroparin (0.6 mL of 10,250 anti-Xa IU/mL) or placebo injections started 3 days before angioplasty and continued for 3 months. Angiography was performed just before and immediately after angioplasty and at follow-up. The primary study end point was angiographic restenosis, assessed by quantitative coronary angiography 3 months after balloon angioplasty. Clinical follow-up was continued up to 6 months. Clinical and procedural variables and the occurrence of periprocedural complications did not differ between groups. At angiographic follow-up, the mean minimal lumen diameter and the mean residual stenosis in the nadroparin group (1.37+/-0.66 mm, 51.9+/-21.0%) did not differ from the corresponding values in the control group (1.48+/-0.59 mm, 48.8+/-18.9%). Combined major cardiac-related clinical events (death, myocardial infarction, target lesion revascularization) did not differ between groups (30.3% versus 29.6%). CONCLUSIONS: Pretreatment with the low-molecular-weight heparin nadroparin continued for 3 months after balloon angioplasty had no beneficial effect on angiographic restenosis or on adverse clinical outcomes. 相似文献
97.
WE Farrell DJ Simpson JE Bicknell AJ Talbot AS Bates RN Clayton 《Canadian Metallurgical Quarterly》1997,57(13):2703-2709
We have screened 57 cases of primary, nonfunctional, pituitary adenomas for loss of heterozygosity of markers on chromosome 9p. Using a panel of 11 microsatellite markers, we found hemizygous deletion with at least one of the markers in 18 tumors (31.5%). The frequency of loss was similar in both noninvasive (8 of 26; 31%) and invasive tumors (10 of 31; 32%), suggesting that loss on this chromosome might be an early event in pituitary tumorigenesis. Two discrete areas of loss were punctuated by a region of retention of heterozygosity between the markers D9S171 and IFNA, indicative of homozygous deletion. However, multiplex PCR analysis (MTS1 and MTS2) and the presence of a 3' untranslated region polymorphism in MTS1 suggested that neither of these tumor suppressor genes was homozygously deleted. In 6 of the 18 tumors showing LOH, sufficient DNA was also available for Southern blot analysis and, in all cases, showed retention of MTS1. Cell mixing experiments of tumor cell DNA homozygously deleted for MTS1 with DNA in which neither copy of the gene was deleted only gave rise to a signal at contamination levels greater than 30% and could discriminate homozygous and hemizygous loss. These studies support the recent findings that mechanisms other than hemi- and homozygous deletion are most likely responsible for the loss of MTS1 gene product in pituitary tumors (M. Woloschak et al., Cancer Res., 56: 2493-2486, 1996.). These data show that losses on either side of 9p21-22, both or either of which may be deleted, are involved in pituitary tumorigenesis and provide evidence for distinct suppressor gene loci, in addition to MTS1, on chromosome 9p. 相似文献
98.
SH Thomas JE Horner K Chew J Connolly B Dorani L Bevan S Bhattacharyya MG Bramble KH Han A Rodgers B Sen B Tesfayohannes H Wynne DN Bateman 《Canadian Metallurgical Quarterly》1997,16(9):495-500
1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately. 相似文献
99.
100.
JG Liese CK Meschievitz E Harzer J Froeschle P Hosbach JE Hoppe F Porter S Stojanov K Niinivaara AM Walker BH Belohradsky 《Canadian Metallurgical Quarterly》1997,16(11):1038-1044
OBJECTIVE: This case-control study investigated the protective efficacy against pertussis of three doses of a two-component acellular pertussis vaccine (manufactured by Biken in Japan) combined with diphtheria and tetanus toxoids (manufactured by Connaught Laboratories in the US) in infants. METHODS: A case-control study was performed in 63 pediatric practices in Germany. Prospective recruitment of 16,780 infants ages 6 to 17 weeks took place between February, 1993, and July, 1994. According to parental choice infants received either Biken acellular pertussis vaccine combined with diphtheria and tetanus toxoids (DTacP) (74.6%) at approximately 2, 4 and 6 months of age, or a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine (10.9%), diphtheria-tetanus toxoids vaccine (12.5%) or no vaccine (2.0%). Prospective surveillance of pertussis cases between February, 1993, and May, 1995, was accomplished by culturing all infants < or =2 years of age presenting with cough > or = 7 days. A pertussis case was defined as any cough of 21 days or longer plus a positive Bordetella pertussis culture or household contact exposure. RESULTS: We identified 241 pertussis cases prospectively by 11,017 B. pertussis cultures and 949 controls matched for age were selected from the same pediatric practices. Medical history and demographic and vaccine status data were collected from each case and for four controls. Data were analyzed through conditional logistic regression taking into account individual matching and adjusting for potential confounding variables. DTacP combined with diphtheria and tetanus toxoids vaccine was 82% protective (95% confidence interval, 68 to 90), diphtheria-tetanus toxoids-whole cell pertussis vaccine was 96% protective (95% confidence interval, 78 to 99). Protection against typical B. pertussis infection characterized by paroxysmal cough lasting > or =21 days was 96% (95% confidence interval, 87 to 99) for DTacP and was 97% (95% confidence interval, 79 to 100) for diphtheria-tetanus toxoids-whole cell pertussis vaccine. Adjustment for potentially confounding variables did not change the results significantly. CONCLUSIONS: Three doses of the two-component acellular pertussis vaccine protected infants against pertussis disease during the period before the recommended booster vaccination. For typical pertussis disease as defined by the WHO efficacy was high and similar to that of a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine. 相似文献