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101.
Five aromatic constituents of essential oils (cineole, citral, geraniol, linalool and menthol) were tested for antimicrobial activity against eighteen bacteria (including Gram-positive cocci and rods, and Gram-negative rods) and twelve fungi (three yeast-like and nine filamentous). In terms of antibacterial activity linalool was the most effective and inhibited seventeen bacteria, followed by cineole, geraniol (each of which inhibited sixteen bacteria), menthol and citral aromatic compounds, which inhibited fifteen and fourteen bacteria, respectively. Against fungi the citral and geraniol oils were the most effective (inhibiting all twelve fungi), followed by linalool (inhibiting ten fungi), cineole and menthol (each of which inhibited seven fungi) compounds. 相似文献
102.
103.
S Komatsu J Panés JM Russell DC Anderson VR Muzykantov M Miyasaka DN Granger 《Canadian Metallurgical Quarterly》1997,29(2):683-689
Recent reports indicate that bacterial endotoxin (lipopolysaccharide) and cytokines elicit a more profound increase in the surface expression of intercellular adhesion molecule-1 (ICAM-1) in cultured endothelial cells derived from spontaneously hypertensive (SHR) versus normotensive Wistar-Kyoto rats (WKY). Our objective in this study was to characterize and compare in vivo ICAM-1 expression in SHR and WKY under basal conditions and after 5 hours of endothelial cell activation with either lipopolysaccharide (5 mg/kg i.p.) or tumor necrosis factor-alpha (TNF-alpha; 1, 5, and 10 micrograms/kg i.p.). ICAM-1 expression was quantified in different tissues by the double-radiolabeled monoclonal antibody technique. When constitutive (baseline) ICAM-1 expression was corrected for endothelial cell surface area, significantly higher values were noted in SHR than WKY but only in splanchnic organs. Lipopolysaccharide and TNF-alpha elicited significant increases in ICAM-1 expression in all tissues of both WKY and SHR. However, the magnitude of the lipopolysaccharide-induced ICAM-1 upregulation in heart, stomach, skeletal muscle, and brain was significantly lower in SHR than WKY. A similar blunted ICAM-1 upregulation was noted in the stomach of SHR after administration of 5 micrograms/kg TNF-alpha. The differences in induced ICAM-1 expression between SHR and WKY do not appear to be due to differences in endothelial cell surface area or plasma glucocorticoid levels. These results suggest that chronic arterial hypertension results in altered ICAM-1 expression on the endothelium, which may contribute to the abnormal inflammatory responses associated with this disease. 相似文献
104.
MOC-31 expression has recently been advocated as an immunohistochemical marker for distinguishing mesothelioma from adenocarcinoma in tissue sections. We studied formalin-fixed, paraffin-embedded tissue from 23 pleural mesotheliomas and 23 primary pulmonary adenocarcinomas for immunoreactivity with anti-MOC-31, a human epithelial-related antigen. All of the 23 adenocarcinomas strongly expressed the marker, whereas only one of the mesotheliomas showed weak reactivity. These results demonstrate the usefulness of anti-MOC-31 in differentiating pulmonary adenocarcinoma from mesothelioma. 相似文献
105.
EG Novoselova VR Makar NV Semiletova SG Kolaeva VB Sadovnikov 《Canadian Metallurgical Quarterly》1998,38(5):690-695
BACKGROUND: The current classification dividing patients with functional gastrointestinal symptoms into subgroups remains controversial. AIMS: To determine whether distinct symptom groupings exist in the community. METHODS: A random sample of Sydney residents in Penrith, Australia was mailed a validated self report questionnaire. Gastrointestinal symptoms including the Rome criteria for irritable bowel syndrome (IBS) and dyspepsia were measured. RESULTS: Among 730 respondents, the 12 month age and gender adjusted prevalence (adjusted to the Australian population) of IBS, dyspepsia, and gastro-oesophageal reflux were 11.8% (95% confidence interval (CI) 9.3 to 14.3%), 11.5% (95% CI 9.6 to 14.6%), and 17.5% (95% CI 14.2 to 19.9%), respectively. In total, 60% of the population reported four or more gastrointestinal symptoms. There was considerable overlap of IBS with dyspepsia and among the dyspepsia subgroups by application of the Rome criteria. Independently, 10 symptom groupings were identified by factor analysis. The underlying constructs measured by these factors were generally the major abdominal syndromes recognised by the Rome classification: dyspepsia, IBS, reflux, painless constipation, painless diarrhoea, and bloating, in addition to a number of more specific symptom groupings. CONCLUSION: Gastrointestinal symptoms are common and overlap in the community, but distinct upper and lower abdominal symptom groupings can be identified. 相似文献
106.
Translocational pausing is a mechanism used by certain specialized secretory proteins whereby discrete domains of a nascent chain destined for the endoplasmic reticulum lumen are transiently exposed to the cytosol. Proteoliposomes reconstituted from total endoplasmic reticulum proteins properly assemble translocationally paused intermediates. The capacity of the translocon to correctly pause the nascent chain is dependent on a glycoprotein fraction whose active component is TRAM. In the absence of TRAM, the normally sealed ribosome-membrane junction still opens in response to a pause transfer sequence. However, nascent chain domains that are not exposed to the cytosol in the presence of TRAM are so exposed in its absence. Thus, TRAM regulates which domains of the nascent chain are visible to the cytosol during a translocational pause. 相似文献
107.
CA Seixas G Hessel CC Ribeiro VR Arruda JM Annichino-Bizzacchi 《Canadian Metallurgical Quarterly》1997,77(2):258-261
Portal vein thrombosis (PVT) is a rare condition affecting both children and adults, and occurs in association with a wide variety of clinical situations. On the other hand, the development of PVT in patients under these situations indicates that other contributing factors could be involved. Recently a missense mutation in the factor V gene (1691G-->A), known as factor V Leiden, has been identified and results in abnormal factor V product, resistant to proteolytic inactivation by activated protein C and thus predisposes to thrombosis. This study was carried out to verify if children with PVT have an increase in frequency of factor V Leiden. Allele-specific restriction analysis and single strand conformational polymorphism (SSCP) were used to test for factor V Leiden in 20 children with PVT and 64 normal children. None of the PVT children were heterozygous or homozygous for the factor V Leiden, and one control child was heterozygous. This study demonstrates that factor V Leiden is not common in children with PVT, and is not a prerequisite for this thrombotic event. 相似文献
108.
To test whether the binding of insulin to an endogenous serum protein can be used to extend the time action of insulin, human insulin was acylated at the epsilon-amino group of Lys(B29) with palmitic acid to promote binding to serum albumin. Size-exclusion chromatography was used to demonstrate specific binding of the resulting analog, [N(epsilon)-palmitoyl Lys(B29)] human insulin, to serum albumin in vitro, and the time action and activity of the analog were determined in vivo using overnight-fasted, insulin-withdrawn diabetic dogs. In the diabetic animal model, the duration of action of [N(epsilon)-palmitoyl Lys(B29)] human insulin administered intravenously was nearly twice that of unmodified human insulin, and the plasma half-life was nearly sevenfold that of the unmodified protein. Administered subcutaneously, [N(epsilon)-palmitoyl Lys(B29)] human insulin had a longer duration of action; a flatter more basal plasma insulin profile; and a lower intersubject variability of response than the intermediate-acting insulin suspension Humulin L (Lilly, Indianapolis, IN). These studies support the concept that modification of insulin to promote binding to an existing serum protein can be used to extend the time action of human insulin. In addition, the time action, pattern, and decreased variability of response to [N(epsilon)-palmitoyl Lys(B29)] human insulin support the development and further testing of this soluble insulin analog as a basal insulin to increase the safety of intensive insulin therapy. 相似文献
109.
In adult horses, three myosin heavy chain (MyHC) isoforms can be identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunohistochemistry using specific anti-MyHC monoclonal antibodies. This report studies the suitability of a consistent SDS-PAGE technique for quantifying MyHC profiles in homogenized cryostate sections of equine gluteus medius muscle biopsies (n = 18). The method used (previously described by R. J. Talmadge and R. R. Roy; J. Appl. Physiol. 1993, 75, 2337-2340) resolved MyHCs in three bands: I, IIB or IIX, and IIA from the fastest to the slowest migration band. The success rate of the protocol for yielding three well-differentiated MyHC bands was 100% and a subsequent quantification by densitometry for each MyHC isoform was obtained in all 18 muscle biopsies. The results obtained with this electrophoretic method were compared with routine myofibrillar adenosine triphosphatase histochemistry and immunohistochemistry using specific anti-MyHC monoclonal antibodies. The percent composition of the three electrophoretically separated MyHC isoforms (I, IIA and IIB or IIX) showed strong positive correlation with percentages of the area occupied in the biopsies by the three major fiber types (I, IIA, and IIB) identified histochemically (r = 0.96, P < 0.001) and immunohistochemically (r = 0.94, P < 0.01). It can be concluded that the electrophoretic method used here for measuring MyHC content is a valid alternative for muscle fiber typing in horses. As it is less costly and time-consuming than both qualitative histochemistry and immunohistochemistry, the method offers new prospects for application in equine experimental studies and veterinary medicine. 相似文献
110.
RR Stotts AR Twardock WM Haschek BW Choi KL Rinehart VR Beasley 《Canadian Metallurgical Quarterly》1997,35(6):937-953
The distribution of tritiated dihydromicrocystin [3H]2H-MCLR was studied in anesthetized specific-pathogen-free pigs. Two doses were administered i.m. and one dose was given via an isolated ileal loop. At 4 hr after i.v. administration of the toxin at 25 micrograms/kg, 64.6% of the total dose (%TD) was located in the liver, with smaller amounts distributed to the kidneys (1.2% TD), lungs (1.75% TD), heart (0.22% TD), ileum (0.13% TD) and spleen (0.04% TD). A similar distribution was found at 4 hr postdosing in pigs given 75 micrograms/kg, although the liver contained a lower fraction of the total dose, at 46.99% TD, and the kidneys had somewhat more, at 2.19% TD, than the low dose. At the high dose, the fractions of the amount given accounted for by the lungs (0.55% TD), heart (0.23% TD), ileum (0.20% TD) and spleen (0.07% TD) were similar to those at the low dose. The livers of the pigs given 75 micrograms/kg via the ileal loop, at 5 hr postdosing, contained 49.5% TD and the ileum had 33.94% TD. Smaller amounts were distributed to kidneys (1.04% TD), lungs (0.65% TD), heart (0.81% TD) and spleen (0.16% TD). The livers of both groups dosed at 75 micrograms/kg contained higher concentrations of toxin, but lower percentages of the total dose, than the livers of pigs dosed at 25 micrograms/kg. Larger increases in serum arginase in the two 75 micrograms/kg groups were associated with histological evidence of more severe liver damage than at the 25 micrograms/kg dose. Analysis of radiolabeled compounds from hepatic tissue using fast atom bombardment mass spectrometry determined that the primary constituent was [3H]2H-MCLR, but two minor radioactive components were also isolated. These findings indicate that [3H]2H-MCLR is rapidly concentrated in the liver of swine, whether given i.v. or via an isolated ileal loop, that at extremely toxic doses uptake is slowed, and that it is as toxicologically active as the parent compound. 相似文献