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OBJECTIVE: To compare the impact upon maternity unit resources and finances of two protocols for induction of labour using prostaglandins. DESIGN: A prospective randomised trial comparing a single dose of prostaglandin E2 (2 mg) in the evening with two doses of prostaglandin E2 (2 mg), the second being given after six hours if labour had not started or the cervix was still unripe, followed if necessary by formal induction of labour by amniotomy and oxytocin infusion 14 to 20 hours after the initial prostaglandin E2 dose. Outcome for nulliparae and multiparae were analysed separately, by treatment intention. SETTING: A maternity unit in a district general hospital delivering > 6000 women annually. PARTICIPANTS: Nine hundred and fifty-five women with viable singleton pregnancies and cephalic presentation at term without previous history of caesarean section who were advised to have labour induced with prostaglandins. MAIN OUTCOME MEASURES: Costs incurred in managing all aspects of labour, including time spent on the antenatal ward and, in the delivery unit; costs associated with formal induction, augmentation of labour and epidural analgesia; costs of intrapartum maternal morbidity, mode of delivery and immediate neonatal care. Costs of postpartum hospital stay were estimated from unit statistics. RESULTS: The overall mean cost of induction of labour was Pounds 5.00 and Pounds 7.22 less per woman for nulliparae and multiparae, respectively, if the two dose regimen was used. The main reason for the differences was due to delivery suite costs from the slightly greater rate of assisted deliveries in the single treatment groups. In contrast, costs for neonatal care were marginally lower if only one prostaglandin dose was used. CONCLUSIONS: The increased drug costs providing two prostaglandin E2 doses when required were off-set by reductions in the costs of other intrapartum interventions for both nulliparae and multiparae. The advantages of less time spent on the antenatal ward for multiparae when two prostaglandin E2 doses were used may be eliminated if amniotomy and oxytocin infusion was commenced six hours after the initial prostaglandin dose had been given if labour had not started. 相似文献
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Serological testing for immunoglobulin G (IgG) antibodies to Helicobacter pylori has proven useful in supporting the diagnosis of infection with this organism, but the clinical value of IgA antibodies in H. pylori-related gastritis remains controversial. The purpose of our study was to determine the frequency of IgA-positive IgG-negative patients with symptoms of gastrointestinal (GI) disorders, thus assessing the clinical utility of IgA testing for H. pylori-related gastritis. It was found previously that the frequency of infected individuals in this category (IgA positive and IgG negative) is about 2%, but a large number of IgG-negative patients with GI disorders suggestive of H. pylori infection have not been investigated until now. 相似文献
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PW Callas KO Leslie AR Mattia DL Weaver D Cook B Travis DE Stanley LA Rogers SL Mount TD Trainer MA Zarka RM Belding 《Canadian Metallurgical Quarterly》1997,21(7):812-819
Accuracy of diagnoses rendered using a live video telepathology network was assessed for permanent sections of surgical pathology specimens. To determine accuracy, telepathology diagnoses were compared with those obtained by directly viewing the glass slide using a standard microscope. A total of 294 cases were read via both telepathology and glass slide by attending pathologists at a tertiary care medical center. Overall accuracy was defined as exact concordance between diagnoses. Clinically insignificant differences in diagnoses were excluded to determine clinically significant accuracy. For the 285 cases with complete data, the overall accuracy for telepathology was 0.912 (95% confidence interval [CI], 0.872-0.941), whereas the overall accuracy for glass slide readings was 0.968 (95% CI, 0.939-0.985). This difference is statistically significant (p = 0.009). When focusing on clinically significant discrepancies, where the difference in diagnosis might affect therapeutic decisions, the video accuracy was only slightly less than the glass slide accuracy (0.965 [95% CI, 0.934-0.982] vs. 0.982 [95% CI, 0.957-0.994], respectively), but this difference is not statistically significant (p = 0.302). Most of the cases with clinically significant differences involved lesions with inherently high interobserver variation. Certainty of diagnosis did not differ between video and glass slide readings (p = 0.911), but there was an association between certainty of diagnosis and diagnostic accuracy for video (p = 0.003 for clinically significant accuracies). Based on these findings, we recommend when using this telepathology system that only preliminary diagnoses should be given in the following situations: for diagnostic areas with known high interobserver variability; when the consultant has any degree of uncertainty about the presence or absence of the lesion in question; and when there is insufficient experience using telepathology as a diagnostic medium. 相似文献
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Red mud, a toxic waste product from bauxite processing, was used as a catalyst for the synthesis of multi-walled carbon nanotubes (MWCNTs) by fluidised bed chemical vapour deposition. The products were analysed using thermogravimetric analysis, Raman spectroscopy, and transmission electron microscopy. Using ethylene at 650 °C a MWCNT yield of 375% (with respect to Fe loading) was obtained. Carbon products were approximately 75% MWCNTs with an IG/ID ratio from Raman spectroscopy of 1.43. The production technique and reaction conditions used are conducive to large-scale CNT production, offering a potential value-added commercial use for red mud. 相似文献