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991.
RM Horton PI Karachunski SA Kellermann BM Conti-Fine 《Canadian Metallurgical Quarterly》1995,19(4):594-597
We describe two approaches for using obsolescent computers, either an IBM PC XT or an Apple Macintosh Plus, to accurately quantify spontaneous rodent activity, as revealed by continuous monitoring of the spontaneous usage of running activity wheels. Because such computers can commonly be obtained at little or no expense, and other commonly available materials and inexpensive parts can be used, these meters can be built quite economically. Construction of these meters requires no specialized electronics expertise, and their software requirements are simple. The computer interfaces are potentially of general interest, as they could also be used for monitoring a variety of events in a research setting. 相似文献
992.
993.
ME Boczar MA Howard EP Rivers GB Martin HM Horst C Lewandowski MC Tomlanovich RM Nowak 《Canadian Metallurgical Quarterly》1995,23(3):498-503
OBJECTIVE: To compare the hemodynamics of closed-chest cardiac massage vs. open-chest cardiac massage in patients resuscitated from cardiac arrest that occurred outside of the hospital. DESIGN: Prospective, non-outcome, case series. SETTING: Large urban emergency department. PATIENTS: Ten adult, normothermic, nontraumatic, out-of-hospital, cardiac arrest patients who failed advanced cardiac life support (ACLS) therapy. INTERVENTIONS: Patients presenting to the hospital in cardiac arrest were managed according to the ACLS protocol at the clinician's discretion. Proximal aortic and central venous pressure catheters were placed to measure arteriovenous compression- and relaxation-phase pressure gradients. After 5 mins of baseline measurements during closed-chest cardiac massage, patients underwent a left lateral thoracotomy, and open-chest cardiac massage was performed for 5 mins. MEASUREMENTS AND MAIN RESULTS: The mean coronary perfusion pressure and compression-phase pressure gradients were 7.3 +/- 5.7 and 6.2 +/- 5.4 mm Hg, respectively, during closed-chest cardiac massage, while increasing to 32.6 +/- 17.8 and 32.6 +/- 29.9 mm Hg, respectively, during open-chest cardiac massage. The differences between both measurements were statistically significant (p < .05). CONCLUSIONS: Open-chest cardiac massage is superior to closed-chest cardiac massage in providing relaxation-phase and compression-phase pressure gradients during cardiac arrest in patients failing current ACLS protocols. During open-chest cardiac massage, all patients exceeded the minimum coronary perfusion pressure of 15 mm Hg, which is recommended to obtain a return of spontaneous circulation. Further outcome studies are needed to determine the timeliness and appropriate indications for open-chest cardiac massage. 相似文献
994.
A study was conducted to estimate the prevalence of Salmonella among broilers retailed at wet-markets and processing plants. Litter and feed samples obtained from both broiler and breeder farms were also examined for Salmonella. A total of 158 out of 445 (35.5%) and 52 out of 104 (50.0%) broiler carcasses obtained from wet-markets and processing plants were contaminated with Salmonella, respectively. Salmonella was isolated from 14 out of 98 (14.3%) samples of intestinal content. Litter samples from broiler and breeder farms were positive for Salmonella, 8/40 (20%) and 2/10 (20%), respectively. Salmonella isolates (230) belonging to 15 different serovars were isolated. Predominant serovars were S. enteritidis, S. muenchen, S. kentucky and S. blockley. 相似文献
995.
JA Kerry MA Priddy TY Jervey CP Kohler TL Staley CD Vanson TR Jones AC Iskenderian DG Anders RM Stenberg 《Canadian Metallurgical Quarterly》1996,70(1):373-382
The human cytomegalovirus (HCMV) DNA polymerase gene (UL54; also called pol) is a prototypical early gene in that expression is mandatory for viral DNA replication. Recently, we have identified the major regulatory element in the UL54 promoter responsive to the major immediate early (MIE) proteins (UL122 and UL123) (J.A. Kerry, M.A. Priddy, and R. M. Stenberg, J. Virol. 68:4167-4176, 1994). Mutation of this element, inverted repeat sequence 1 (IR1), abrogates binding of cellular proteins to the UL54 promoter and reduces promoter activity in response to viral proteins in transient-transfection assays. To extend our studies on the UL54 promoter, we aimed to examine the role of IR1 in UL54 regulation throughout the course of infection. These studies show that viral proteins in addition to the MIE proteins can activate the UL54 promoter. Proteins from UL112-113 and IRS1/TRS1, recently identified as essential loci for transient complementation of HCMV oriLyt-dependent DNA replication, were found to function as transactivators of the UL54 promoter in association with MIE proteins. UL112-113 enhanced UL54 promoter activation by MIE proteins three- to fourfold. Constitutive expression of UL112-113 demonstrated that the MIE protein dependence of UL112-113 transactivational activity was not related to activation of cognate promoter sequences, suggesting that UL112-113 proteins function in cooperation with the MIE proteins. Mutation of IR1 was found to abrogate stimulation of the UL54 promoter by UL112-113, suggesting that this element is also involved in UL112-113 stimulatory activity. These results demonstrate that additional viral proteins influence UL54 promoter expression in transient-transfection assays via the IR1 element. To confirm the biological relevance of IR1 in regulating UL54 promoter activity during viral infection, a recombinant virus construct containing the UL54 promoter with a mutated IR1 element regulating expression of the chloramphenicol acetyltransferase (CAT) reporter gene (RVIRmCAT) was generated. Analysis of RVIRmCAT revealed that mutation of IR1 dramatically reduces UL54 promoter activity at early times after infection. However, at late times after infection CAT expression by RVIRmCAT, as assessed by RNA and protein levels, was approximately equivalent to expression by wild-type RVpolCAT. These data demonstrate IR1-independent regulation of the UL54 promoter at late times after infection. Together these results show that multiple regulatory events affect UL54 promoter expression during the course of infection. 相似文献
996.
I Iacobiciu V Stef?noiu Z Laz?r R Olariu L Negru?iu A Ni?u M B?rsan S R?du? L Dan 《Canadian Metallurgical Quarterly》1996,55(3):263-274
An epidemiological study was performed on a lot of 505 adult subjects (over 20 years old) diagnosed with E.granulosus hydatidosis and operated in surgery units in hospitals from such towns as Timi?oara, Arad and Re?ita (1985-1992). The incidence of hydatid infection was almost uniformly distributed by sexes, being a little higher in rural areas (52.0%); the highest number of cases was reported in Timi? County (63.6%), followed by Cara?-Severin County (21.2%). Hydatidosis was most frequently found in liver (67.5%) and lungs (23.7%) and more rarely in kidneys (0.4%), brain (0.2%), pancreas (0.2%), ovary (0.2%). Secondary hydatidosis was reported on 12.7% of cases and multiple cyst forms in 12.7% of cases. The distribution of cases by age group was relatively balanced, a slightly increased incidence being found in the 20-29 years age group (23.2%), about 1/3 of pulmonary localizations being reported in the age group. Post-surgery complications were reported in 13.5% of the total hepatic localizations and in 30% of the pulmonary localizations. The average number of days in hospital was 29.5 days/case. The average morbidity in the adult population in Banat over an eight years time interval was 5.36%ooo, being higher in Timi? county-7.8%ooo where a peak (11%ooo) was reported in 1987. 相似文献
997.
998.
999.
1000.
Glycosaminoglycans (GAGs), and in particular hyaluronan, are known to play a role in tumour cell migration, invasion and metastasis. Conditioned medium from two human metastatic melanoma cell lines (Hs294T and C8161) shows potent fibroblast GAG-synthesis-stimulating activities which are active in fibroblast cultures derived from different anatomical sites. This ability is not specific to melanoma cells and is observed in several carcinoma cell lines. Initial characterisation studies have demonstrated that the GAG-stimulating activities in the medium conditioned with melanoma cells show a degree of heat and trypsin resistance. Fractionation of the conditioned medium with Amicon ultrafiltration membranes of various molecular weight cut-offs, ranging from 1 to 30 kD, resulted in a total loss of activity. Activity could be regained by recombination of the concentrated fraction with the filtrate, suggesting more than one factor to be involved in GAG stimulation, with a degree of interdependence between the individual fractions. The fraction greater than 30 kD and that less than 1 kD appear to contain the majority of the GAG-stimulating activity. 相似文献