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101.
SE Kenny JM Vanderwinden RJ Rintala MG Connell DA Lloyd JJ Vanderhaegen MH De Laet 《Canadian Metallurgical Quarterly》1998,33(1):94-98
BACKGROUND: Previous studies have suggested altered responses to repeat skin tests in the sites of IgE-mediated late-phase reactions (LPRs) induced within the previous 48 hours. To explore the possible modulation of LPRs in such rechallenge sites, we compared inflammatory responses in skin chambers induced over previous LPR and control sites. METHODS: Skin blisters were induced and unroofed in 12 human subjects over two sites of previous LPRs induced by intradermal injection of pollen antigens 24 hours or 48 hours earlier and two sites previously injected with buffer diluent (B). Skin chambers containing the same antigens were appended to one intradermal antigen site (called Ag/Ag) and one intradermal B site (B/Ag), and B-containing chambers were placed over antigen (Ag/B) and B (B/B) intradermal sites. Fluids were collected after the first and the second through fifth hours of challenge. RESULTS: In skin chamber challenges 24 hours after the intradermal injection, there was no significant difference after the first hours between the Ag/Ag or B/Ag sites in either histamine or tryptase levels; both were significantly higher than at Ag/B or B/B sites (p < 0.01). The same pattern of events was seen in fluids obtained from the second through fifth hours. The same pattern of findings was seen in examination of levels of the total leukocyte accumulation, total eosinophil accumulation, and frequency of activated (EG2+) eosinophils. Levels of lactoferrin, released from activated neutrophils, and eosinophil cationic protein, released from activated eosinophils, were also similar at Ag/Ag and B/Ag sites; both were significantly higher than at B/B sites, whereas levels at Ag/B sites were intermediate between those found at B/Ag and B/B sites. The pattern of events in skin chamber challenges 48 hours after intradermal injection was similar to that seen at 24 hours, except that levels of inflammatory mediators/cells in Ag/B sites were more intermediate between the B/Ag and B/B sites. CONCLUSION: There is no significant alteration of mediator or inflammatory cell responses after antigen rechallenge of previous LPR sites when compared with those found in antigen challenge of non-LPR sites. 相似文献
102.
I Orlow A Iavarone SJ Crider-Miller F Bonilla E Latres MH Lee WL Gerald J Massagué BE Weissman C Cordón-Cardó 《Canadian Metallurgical Quarterly》1996,56(6):1219-1221
Mammalian cyclin-dependent kinase inhibitors fall into two families, the INK4 and the CIP/KIP. The CIP/KIP family comprises three structurally related members, including p21CiP1/WAF1, p27KIP1, and p57KIP2. These proteins are all capable of inhibiting the progression of the cell cycle by binding and inhibiting G(1) cyclin/cyclin-dependent kinase complexes. In humans, p57KIP2 is expressed specifically in skeletal muscle, heart, brain, kidney, and lung. Human KIP2 resides in 11p15.5, a chromosomal region that is a common site for loss of heterozygosity in certain sarcomas, Wilms' tumors, and tumors associated with the Beckwith-Wiedemann syndrome. Because of the function, selective expression, and chromosomal location of p57KIP2, we undertook the present study to search for potential mutations of KIP2 in a cohort of 126 tumors composed of 75 soft tissue sarcomas and 51 Wilms' tumors. The KIP2 gene was characterized by Southern blot, comparative multiplex PCR, PCR -single-strand conformational polymorphism, and DNA sequencing assays in these neoplasms. Deletions of the KIP2 gene or point mutations at the region encoding the cyclin-dependent kinase inhibitory domain were not found in the tumors analyzed. The absence of KIP2 mutations might indicate that these tumors arise due to defects at a closely linked but separate locus. Alternatively, similarly to the mouse homologue, inactivation of KIP2 could occur via genomic imprinting. 相似文献
103.
Six healthy male subjects aged 21-35 years participated in the present study. The subjects were exposed to dim light (150 lux) or bright light (3000 lux) at eye level, from 19.00 to 21.30 h for 5 days. Rectal temperature and wrist activity were monitored throughout the study period. Rectal temperature nadir was delayed significantly after the bright light exposure. Ease in sleep initiation and overall sleep quality, measured by questionnaire, were aggravated significantly by the evening bright light exposure. These results suggest that strong illumination at night may disturb nocturnal sleep. 相似文献
104.
We systematically examined relations among 6 measures of child language derived from 3 sources, including observations of the child's speech with mother, experimenter assessments, and maternal reports. A total of 184 20-month-olds and their mothers contributed complete information about child language comprehension and expression. Correlations of child language measures with socioeconomic status and maternal education were accounted for, as were correlations of child language measures with mothers' verbal intelligence, maternal report measures with mothers' tendency to respond in a socially desirable fashion, and experimenter assessments with child social competence. Structural equation modeling supported (1) strong relations among child language measures derived from observations of the child's speech with mother, experimenter assessments, and maternal reports; (2) the loading of multiple measures of child language from different sources on a single latent construct of vocabulary competence; and (3) the predictive validity of the vocabulary competence latent variable at 20 months, as well as receptive vocabulary specifically, for both verbal and performance IQ (verbal better than performance) at 48 months. Neither an index of child monologing (a nonvocabulary language measure) nor symbolic play (a nonlinguistic representational measure) covaried with vocabulary competence. Girls consistently outperformed boys on individual language measures, but no differences emerged in any model in the fit for boys and girls. 相似文献
105.
J Schwaller J Frantsve J Aster IR Williams MH Tomasson TS Ross P Peeters L Van Rompaey RA Van Etten R Ilaria P Marynen DG Gilliland 《Canadian Metallurgical Quarterly》1998,17(18):5321-5333
Recent reports have demonstrated fusion of the TEL gene on 12p13 to the JAK2 gene on 9p24 in human leukemias. Three variants have been identified that fuse the TEL pointed (PNT) domain to (i) the JAK2 JH1-kinase domain, (ii) part of and (iii) all of the JH2 pseudokinase domain. We report that all of the human TEL/JAK2 variants, and a human/mouse chimeric hTEL/mJAK2(JH1) fusion gene, transform the interleukin-3 (IL-3)-dependent murine hematopoietic cell line Ba/F3 to IL-3-independent growth. Transformation requires both the TEL PNT domain and JAK2 kinase activity. Furthermore, all TEL/JAK2 variants strongly activated STAT 5 by phosphotyrosine Western blots and by electrophoretic mobility shift assays (EMSA). Mice (n = 40) transplanted with bone marrow infected with the MSCV retrovirus containing either the hTEL/mJAK2(JH1) fusion or its human counterpart developed a fatal mixed myeloproliferative and T-cell lymphoproliferative disorder with a latency of 2-10 weeks. In contrast, mice transplanted with a TEL/JAK2 mutant lacking the TEL PNT domain (n = 10) or a kinase-inactive TEL/JAK2(JH1) mutant (n = 10) did not develop the disease. We conclude that all human TEL/JAK2 fusion variants are oncoproteins in vitro that strongly activate STAT 5, and cause lethal myelo- and lymphoproliferative syndromes in murine bone marrow transplant models of leukemia. 相似文献
106.
MH Merson 《Canadian Metallurgical Quarterly》1998,338(12):836; author reply 840-836; author reply 841
107.
MH Nantz L Li J Zhu KL Aho-Sharon D Lim KL Erickson 《Canadian Metallurgical Quarterly》1998,1394(2-3):219-223
We have prepared a panel of lipidic ammonium tetrafluoroborate salts that contain trifluoromethyl, trichloromethyl, and methyl groups attached to the headgroup. 19F-NMR analyses of the cationic lipid panel revealed that the differences in electron-withdrawal from the ammonium ion headgroup accounted for differences in ion-pairing. Exchange of the tetrafluoroborate counterion by complexation to DNA-phosphate of a reporter gene enabled us to probe the influence of inductive electron-withdrawal in cationic lipid-mediated DNA transfection. We tested the lipid panel for transfection activity in two cell lines. The results indicate that the inductive effects of electron-withdrawing functionality diminish transfection activity in modest (2-4-fold) increments. The present study suggests that the mechanism whereby poly(alcohol)- or poly(ether)-substituted headgroups improve DNA transfection is not based on electronic activation of the ammonium ion. 相似文献
108.
A new enzyme, geranylpyrophosphate:olivetolate geranyltransferase (GOT), the first enzyme in the biosynthesis of cannabinoids could be detected in extracts of young leaves of Cannabis sativa. The enzyme accepts geranylpyrophosphate (GPP) and to a lesser degree also nerylpyrophosphate (NPP) as a cosubstrate. It is, however, specific for olivetolic acid; its decarboxylation product olivetol is inactive as a prenyl acceptor. 相似文献
109.
110.
In 13 patients with systemic lupus erythematosus, globulin fractions of sera from serial bleedings were assayed for the induction of serotonin release from normal platelets. Releasing activity appeared at some time in the sera of seven patients, five of whom had episodes of thrombocytopenia. Conversely, only one patient manifested thrombocytopenia without the occurrence of serotonin releasing activity at any time. In three patients with episodes of thrombocytopenia, increases in serotonin releasing activity temporally coincided with drops in platelet count. These data show that levels of circulating platelet serotonin releasing factor(s) vary in the course of systemic lupus erythematosus and these variations may be inversely related to the platelet count in particular patients. 相似文献