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51.
Chronic myelogenous leukemia (CML) is a myelo-proliferative disorder which, after a chronic phase which lasts an average of 3 years, evolves into an acute disease which is resistant to chemotherapy. Nevertheless, a few studies have reported cases in which partial or complete hematologic, cytogenetic and/or molecular remission of the disease were observed either spontaneously or after non intensive chemotherapy, with or without medullar aplasia. Some of these patients later relapsed into a blast crisis. We report a case of CML with clinical and hematologic remission for 19 years after two cycles of busulphan not causing medullar aplasia, negative for the BCR/ABL gene by Southern blot but with the gene's mRNA detectable by hot start nested RT-PCR. 相似文献
52.
HK Parmentier G De Vries Reilingh MG Nieuwland 《Canadian Metallurgical Quarterly》1998,66(3-4):367-376
Mitogen-induced cutaneous hypersensitivity was evaluated in chickens selected for high and low antibody responses to SRBC, and in a random bred control line. Wing web swelling responses were found after subcutaneous administration of phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM), and Escherichia coli lipopolysaccharide (LPS), respectively, in all three lines. All mitogens induced significant acute 4 h wing web swelling responses, followed by a significant (classical) late 24 h wing web swelling response. The 4 h responses were significantly lower in the L line, whereas a tendency for lower responses at 24 h in the L line was found as well. Immunohistochemical evaluation of the early and late wing web swelling responses revealed extravascular localisation of leukocytes at 24 h after sensitization with mitogens, which consisted of CD4+ cells, CD8+ cells, TCR-1+ cells, and heterophils, but no B cells, whereas the 4 h swelling response was primarily characterized by oedema. Cutaneous hypersensitivity either initiated by T-cell mitogens as well as B-cell mitogens may depend for an important part on the rapid induction of local homing of lymphocytes towards the sensitizing agent, which may be mediated by an acute local expression of molecules with chemo-attractive capacities. Interpretation of cellular immunity responses in vivo such as delayed-type hypersensitivity should therefore incorporate oedema-initiating characteristics of sensitizing agents. The relationship between the magnitude of cutaneous hypersensitivity to mitogens and selection for antibody responsiveness is discussed. 相似文献
53.
During their first year of life sheep acquire parasites through grazing, and simultaneously build up an immunity to infection. At the beginning of each year non-immune lambs are introduced onto contaminated pasture. We represent this process by differential equations describing the within-year dynamics, and defining a difference equation that describes the between-year dynamics. An example with two system parameters is analysed in detail. It is shown that regions exist in parameter space where periodic (between-year) or aperiodic solutions occur. Parasite control schemes could change the system dynamics from a stable equilibrium to complicated long-term fluctuations. 相似文献
54.
MG Arvystas 《Canadian Metallurgical Quarterly》1996,8(6):279-283
The paper investigated the chromatographic conditions for TLC analysis of metamphetamine on silica gel and the lipophilic stationary phase RP V 18 in order to qualitatively analyze the drug in urine samples. Attention was also paid to chemical detection. Five detection reagents were tested, out of which Fast Black K salt, yielding orange-red spots with a detection limit of 1 microgram, proved to be the best. In the analysis of metamphetamine in the samples of model urine, the best results were achieved on Kieselgel. Using the developing system ethyl acetate-ethanol-concentrated solution of ammonia (36:2:2), a complete separation of the metamphetamine spot from the spots of ballast from the biological matrix was achieved. 相似文献
55.
M Montagna O Serova BS Sylla MG Mattei GM Lenoir 《Canadian Metallurgical Quarterly》1996,98(6):738-740
The h-PRL-1 gene codes for a new phosphotyrosine phosphatase that may play an important role in the control of basic cellular processes such as cell growth and proliferation. Using the cDNA of the h-PRL-1 gene as a probe, we examined a somatic mouse and hamster x human hybrid panel and found that chromosomes 1, 17 and 11 harbor sequences homologous to h-PRL-1. By in situ hybridization of metaphase spreads, subchromosomal localizations were determined at bands 1p35-p34, 17q12-q21 and 11q24-q25; in addition, a faint signal was detected at 12q24. The chromosomal assignment of the genes homologous to h-PRL-1 will help the investigation of its possible involvement in human diseases involving genetic alteration at these chromosomal regions. 相似文献
56.
57.
MG Netea PN Demacker N de Bont OC Boerman AF Stalenhoef JW van der Meer BJ Kullberg 《Canadian Metallurgical Quarterly》1997,65(7):2663-2667
Recent studies have suggested the use of lipoproteins as an adjuvant treatment of lethal gram-negative infections. However, other important microorganisms for the etiology of sepsis, such as Candida species, grow better in lipid-rich environments. We investigated the effect of hyperlipoproteinemia on systemic candidiasis in low-density-lipoprotein-receptor-deficient (LDLR-/-) mice, in which the loss of the receptor results in a seven- to ninefold-higher plasma LDL level than that in their wild-type littermates (C57BL/6J). LDLR-/- mice died earlier, and the outgrowth of Candida albicans in the kidneys and livers of LDLR-/- mice was significantly higher compared with that of controls. After infection, circulating cytokine concentrations were significantly higher in LDLR-/- mice. In vitro, C. albicans grew better in plasma samples of LDLR-/- mice than in control plasma samples and peritoneal macrophages of LDLR-/- mice challenged with heat-killed C. albicans produced more cytokines than did those of controls. This latter phenomenon was probably due to increased binding of yeast cells to macrophages of LDLR-/- mice. These data suggest that hyperlipoproteinemia is deleterious in systemic candidiasis. 相似文献
58.
MG Olde Rikkert P Deurenberg RW Jansen MA van't Hof WH Hoefnagels 《Canadian Metallurgical Quarterly》1997,52(3):M137-M141
BACKGROUND: Multifrequency Bioelectrical Impedance Analysis (MFBIA) is a novel method to assess body composition in elderly subjects. However, it is unclear whether MFBIA can detect changes in body water compartments in elders. We aimed to determine the within-subject variability of MFBIA and the responsiveness to a diuretic intervention in aged subjects with a stable fluid balance. METHODS: We selected 12 healthy active elderly subjects (5 male, 7 female) with a mean age of 75 years. Total body water and extracellular fluid (ECF) were measured by deuterium oxide- and potassium bromide-dilution techniques. Within-subject variability in total body MFBIA was assessed by performing four measurements at 1, 5, 50, and 100 kHz within a 2-month period. Subsequently, responsiveness of MFBIA to the ECF loss caused by oral administration of 40 mg of furosemide was determined. RESULTS: Within-subject variability in MFBIA at 1, 5, 50, and 100 kHz expressed as standard deviations was 21, 19, 14, and 14 Ohm (omega), respectively. Furosemide caused a mean weight loss of 1.8 +/- 0.6 kg, which resulted in significant increases in impedance of 57 +/- 24 omega at 1 kHz and 37 +/- 12 omega at 100 kHz (p < .001). The responsiveness of MFBIA for the diuretic intervention was best at 5 kHz (responsiveness index = 1.98). CONCLUSIONS: Within-subject variability of MFBIA was small in healthy elderly subjects with stable fluid balance. Responsiveness of MFBIA to 9% furosemide-induced ECF loss was excellent. These data support the necessity for further clinical assessment of the value of MFBIA in monitoring fluid balance in geriatric patients. 相似文献
59.
Despite the availability of several instruments to evaluate quality of life (QL) over time in patients with lung cancer, barriers in measurement remain. This methodological study used LCSS data (Lung Cancer Symptom Scale, a disease- and site-specific QL measure) to examine analysis methods to quantify QL where data needed for serial evaluation may be missing. Data from two large randomized trials, conducted at 30 centers, of a new combination chemotherapy regimen incorporating a new agent for patients (n = 673) with Stage III and IV non-small cell lung cancer were obtained for this study. QL had been prospectively measured at baseline, day 29, and every six weeks thereafter using the LCSS. For the slope analysis (SA) and area under the curve (AUC) analyses, an adjustment score of zero was used to indicate QL on the day of death (mortality adjustment) and each subsequent day until the end of the assessment period. Significant differences in QL, symptom scores and known prognostic factors at baseline were found in the attrition group. SA and AUC analysis allowed inclusion of 581 patients, giving an adequacy rate of 86%. By using a mortality adjustment, an additional 45 patients were included, increasing the inclusion rate to 93%. With the use of the mortality adjustment, QL was shown to decline over the interval, as opposed to rise if the adjustment had not been performed. The conclusions of the study were: (1) analysis for serial data using SA and AUC provides useful, but differing information; (2) when attrition (caused by death) is a factor, a mortality adjustment presented a more accurate assessment of QL as an endpoint; (3) more frequent evaluations of QL will capture rapid changes in patient status and reduce the attrition bias; (4) all patients should be followed until they die; and (5) QL should be given full consideration as a primary endpoint separate from survival. 相似文献
60.
PR Romano F Zhang SL Tan MT Garcia-Barrio MG Katze TE Dever AG Hinnebusch 《Canadian Metallurgical Quarterly》1998,18(12):7304-7316
The human double-stranded RNA (dsRNA)-dependent protein kinase PKR inhibits protein synthesis by phosphorylating translation initiation factor 2alpha (eIF2alpha). Vaccinia virus E3L encodes a dsRNA binding protein that inhibits PKR in virus-infected cells, presumably by sequestering dsRNA activators. Expression of PKR in Saccharomyces cerevisiae inhibits protein synthesis by phosphorylation of eIF2alpha, dependent on its two dsRNA binding motifs (DRBMs). We found that expression of E3 in yeast overcomes the lethal effect of PKR in a manner requiring key residues (Lys-167 and Arg-168) needed for dsRNA binding by E3 in vitro. Unexpectedly, the N-terminal half of E3, and residue Trp-66 in particular, also is required for anti-PKR function. Because the E3 N-terminal region does not contribute to dsRNA binding in vitro, it appears that sequestering dsRNA is not the sole function of E3 needed for inhibition of PKR. This conclusion was supported by the fact that E3 activity was antagonized, not augmented, by overexpressing the catalytically defective PKR-K296R protein containing functional DRBMs. Coimmunoprecipitation experiments showed that a majority of PKR in yeast extracts was in a complex with E3, whose formation was completely dependent on the dsRNA binding activity of E3 and enhanced by the N-terminal half of E3. In yeast two-hybrid assays and in vitro protein binding experiments, segments of E3 and PKR containing their respective DRBMs interacted in a manner requiring E3 residues Lys-167 and Arg-168. We also detected interactions between PKR and the N-terminal half of E3 in the yeast two-hybrid and lambda repressor dimerization assays. In the latter case, the N-terminal half of E3 interacted with the kinase domain of PKR, dependent on E3 residue Trp-66. We propose that effective inhibition of PKR in yeast requires formation of an E3-PKR-dsRNA complex, in which the N-terminal half of E3 physically interacts with the protein kinase domain of PKR. 相似文献