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991.
KG McGuigan TM Joyce RM Conroy JB Gillespie M Elmore-Meegan 《Canadian Metallurgical Quarterly》1998,84(6):1138-1148
A series of experiments is reported to identify and characterize the inactivation process in operation when drinking water, heavily contaminated with a Kenyan isolate of Escherichia coli, is stored in transparent plastic bottles that are then exposed to sunlight. The roles of optical and thermal inactivation mechanisms are studied in detail by simulating conditions of optical irradiance, water turbidity and temperature, which were recorded during a series of solar disinfection measurements carried out in the Kenyan Rift Valley. Optical inactivation effects are observed even in highly turbid water (200 ntu) and at low irradiances of only 10 mW cm-2. Thermal inactivation is found to be important only at water temperatures above 45 degrees C, at which point strong synergy between optical and thermal inactivation processes is observed. The results confirm that, where strong sunshine is available, solar disinfection of drinking water is an effective, low cost method for improving water quality and may be of particular use to refugee camps in disaster areas. Strategies for improving bacterial inactivation are discussed. 相似文献
992.
XM Mueller HT Tevaearai W Bosshard P Vogt A Delabays JB Favre P Ravussin LK von Segesser F Stumpe 《Canadian Metallurgical Quarterly》1998,128(48):1906-1909
To avoid the inflammatory syndrome generated by cardiopulmonary bypass, a new surgical technique, minimal invasive direct coronary artery bypass (MIDCAB), has been developed. An anastomosis is performed between the left internal mammary artery (LIMA) and the left anterior descending artery (LAD) on a beating heart, through a limited anterior thoracotomy. We describe our experience with this technique. Ten consecutive patients underwent a MIDCAB procedure. (9 males, age 65.9 +/- 9 years). There were 8 bypasses of the LIMA on the LAD, one bilateral mammary bypass on the LAD and the right coronary artery, and one conversion to a standard sternotomy with CPB for a saphenous vein bypass on the LAD because of injury to the LIMA (2nd case). There was one redo for haemostasis of the mammary artery bed (3rd case). The first 3 patients required postoperative blood transfusion. From the 4th operation onwards, with the introduction of new instrumentation which was better adapted to the narrowness of the surgical field, there were no further surgical complications. During the follow-up (mean 5 months; range 2-9), no patient suffered anginal recurrence. With the improvement of instrumentation, the MIDCAB technique offers satisfactory short- and mid-term results, while avoiding CPB with its adverse effects. Lastly, the cosmetic result is far better than with the conventional procedure. 相似文献
993.
J Ferrières D Taraszkiewicz JB Ruidavets V Graille J Fauvel B Perret H Chap D Carrié M Elbaz J Puel 《Canadian Metallurgical Quarterly》1998,47(8):543-548
In order to achieve an overview of neuroradiology in Europe a questionnaire was sent to all ESNR National Delegates. The answers received were submitted to a data-based analysis, leading to the conclusion that neuroradiology is an expanding discipline among neurological sciences. 相似文献
994.
995.
Membrane penicillinase (penicillin amido-beta-lactamhydrolase, EC 3.5.2.6) from Bacillus licheniformis bears a striking resemblance to the major outer membrane lipoprotein of Escherichia coli. It can be specifically labeled in vivo with [3H]glycerol, [35S]cysteine, or [3H]palmitate but not by [32P]orthophosphate. The labeled residues are located at or near the NH2 terminus of the membrane penicillinase because they can be completely removed by trypsin which cleaves a hydrophobic peptide(s) from the NH2 terminus, thereby rendering the enzyme hydrophilic. The membrane penicillinase produced by the 749/C gene carried in E. coli on phage lambda is similar to the enzyme formed in strain 749/C itself. The peptide antibiotic globomycin, which prevents processing of the E. coli prolipoprotein, severely inhibited the attachment of [3H]palmitate or [3H]glycerol to the 749/C enzyme (either in B. licheniformis 749/C or in E. coli), blocked the accumulation of penicillinase in the plasma membrane, and enhanced the formation of exoenzyme. Under the same conditions, globomycin does not prevent the attachment of palmitate or glycerol to the E. coli prolipoprotein but inhibits processing of the modified precursor to the mature lipoprotein. These results are in contrast with the lack of effect of globomycin on the RTEM-beta-lactamase of E. coli which has no detectable hydrophobic membrane form and was not labeled with palmitate or glycerol. 相似文献
996.
IJ Alosachie JW Terryberry D Mevorach Y Chapman M Lorber D Torre P Youinou JB Peter Y Shoenfeld 《Canadian Metallurgical Quarterly》1998,16(3):275-284
Dysplasia in inflammatory bowel disease (IBD) is categorized as either flat or associated with a raised lesion or mass (dysplasia-associated lesion or mass [DALM]). One specific subtype of a dysplasia-associated lesion or mass consists of isolated discrete nodules or polyps that are difficult to distinguish from sporadic adenomas. Because the clinical management of these two lesions is different, we performed this study to (1) evaluate the clinical presentation, pathologic features, and natural history of polypoid dysplastic lesions and sporadic adenomas in patients with IBD and (2) determine whether there are clinical, endoscopic, or pathologic findings useful in differentiating between these two lesions. The morphologic features of 89 benign polypoid epithelial neoplasms from 59 patients with IBD (51 with ulcerative colitis, 8 with Crohn's colitis) were evaluated and correlated with the clinical, endoscopic, and follow-up data. In a separate analysis, patients were categorized arbitrarily as having (1) a probable sporadic adenoma if the polypoid epithelial neoplasm was not located within areas of histologically proven colitis, (2) a probable IBD-associated polypoid dysplasia if the lesion developed within an area of colitis, and associated flat dysplasia or an adenocarcinoma was detected during follow-up evaluation or (3) an indeterminate polyp, which was seen in the remainder of the cases. The clinical, endoscopic, and histologic data were compared among these three patient and polyp subgroups. There were 35 males and 24 females (median age, 57 years; range, 27-85 years). Median duration of disease was 10 years. Forty-nine percent of the patients had pancolitis; 66% had histologically active disease at the time of presentation. Nearly 70% of patients had only one polyp; the majority occurred in either the left colon or the rectum (66%). Most polyps were described as a sessile nodule, whereas only 7 (7.8%) were pedunculated. Polyps ranged from 2 mm to 50 mm (median, 5 mm); most had a tubular architecture (84.3%) and contained low-grade dysplasia (64%). In addition, most polyps had mildly increased lamina propria and intraepithelial neutrophilic and mononuclear inflammation. At follow-up evaluation (40 patients; median follow-up time, 13 months; range, 1-78 months), a further neoplastic lesion developed in 20%; low-grade flat dysplasia was seen in 5 (12.5%), and adenocarcinoma developed in 3 (7.5%). However, dysplasia or adenocarcinoma did not develop in the patients who had polyps located outside of areas of histologically proven colitis. In addition, at least one more benign polypoid epithelial neoplasm developed in 15 of 40 patients (37.5%). Patients with probable IBD-associated polypoid dysplasia had a statistically significant (p < 0.05), longer disease duration than patients with probable sporadic adenoma. A statistically significant, higher proportion of polyps with tubullovillous or villous architecture, an admixture of normal and dysplastic epithelium at the surface of the polyps, and increased lamina propria mononuclear inflammation was noted in probable IBD-associated polypoid dysplastic lesions compared with those considered to be sporadic adenomas. Several clinical and pathologic features may be useful to help categorize a polypoid dysplastic lesion as a sporadic adenoma or an IBD-related neoplasm in a patient with IBD. This distinction is important because the natural history of these two lesions (as shown by the results of this study) and their subsequent management are quite different. 相似文献
997.
The validity of the Tritrac-R3D activity monitor for the assessment of physical activity: II. Temporal relationships among objective assessments 总被引:1,自引:0,他引:1
Today the organ donor operation in brain dead donors is mostly projected as multiple organ procurement (MOP). Not only the kidneys, but heart and liver or additionally lungs and pancreas are removed in MOP. A good synchronization between the collaborating transplantation groups (thoracic and abdominal surgeon, urologist) is essential to prevent loss of an organ because of technical problems. In Germany urologists perform more than 40% of kidney transplantations. These urologic institutions perform the cadaver kidney retrievals and participate on MOP. If possible, an urologist experienced in renal transplantation should contribute to the care for quality of the kidneys. Since 1987 the transplant center of Bremen obtained 390 donor registrations. 202 organ donor operations have been performed (106 MOP and 96 exclusive kidney retrievals). 398 donor kidneys have been collected and 382 could be transplanted. 相似文献
998.
JB Whitney A Leder J Lewis RA Popp C Paszty EM Rubin WR Shehee TM Townes O Smithies 《Canadian Metallurgical Quarterly》1998,36(1-2):65-77
Because of its high sensitivity, bioluminescence (BL) is an excellent alternative to radioactive quantitation of cytokine RT-PCR-derived products. BL also allows detection of amplicons at cycle numbers not normally detectable using radioactivity. No direct comparisons between these two methods have been made. In this study, the sensitivities of BL using recombinant aequorin, a flash-type luminescent tag capable of detecting signal to attomolar (10(-18) M) levels and radio imaging (RI) were directly compared. In addition, the application of BL for detecting cytokine message from biologic samples was examined. BL was 30- to 60-fold more sensitive than RI in detecting human IL-2 and CD3delta amplicons. This difference was particularly found during low cycle PCR, but was less at higher cycle numbers. The ability of BL to detect differences in cytokine message in stimulated and unstimulated human peripheral blood mononuclear cells was also evaluated. Using linear regression analysis, we observed up to 5,000-fold increases in RT-PCR amplified-mRNA in stimulated cells for IL-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10 and GM-CSF compared to unstimulated cells. Changes in CD3delta, TNF alpha or IL-12 were not observed or quantitated. We present a novel aequorin-based application of bioluminescent technology to directly quantitate RT-PCR amplicons and to investigate the induction of human cytokine expression. Significant advantages of this sensitive bioluminescent method compared with radioactive methods are its abilities to quantitate amplicons in a PCR cycle range where linear detection is most robust and to analyze products in an automated, open-architecture microtiter plate format. 相似文献
999.
1000.