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991.
992.
JJ Kim SD Kim KH Meng YO Ahn YT Yum HC Oh DB Lee SI Lee BY Chun JS Choi 《Canadian Metallurgical Quarterly》1998,13(3):247-262
This study aimed to find out the morbid status of Korean physicians living in Korea, as one part of a feasibility study on the Korean physician cohort. It was performed by mail survey using a self-administered questionnaire from Jan. 1, 1995 through Dec. 31, 1995. Study subjects were 21,552 including 17,877 (81.1%) males and 3,384 (15.5%) females. Person based prevalence rate of disease was 17.7% (18.3% for males and 13.8% for females) with the rate increasing with age. The disease group showing the highest prevalence rate was circulatory diseases (5.16%) for males, and respiratory disease (3.13%) for females. The individual disease showing the highest prevalence rates was hypertension (3.77%) for males and allergic rhinitis (2.25%) for females. The person based disease experience rate was 36.2% (36.9% for males, 32.7% for females) with the rate increasing with age. The disease group showing the highest disease experience rate was digestive disease for both sexes (10.05% for males, 7.42% for females). Individual disease showing the highest disease experience rate was hypertension (5.00%) for males and allergic rhinitis (4.08%) for females. There were different ranks of both prevalence and disease experience rate depending on age in both sexes. 相似文献
993.
A Anumanthan A Bensussan L Boumsell AD Christ RS Blumberg SD Voss AT Patel MJ Robertson LM Nadler GJ Freeman 《Canadian Metallurgical Quarterly》1998,161(6):2780-2790
Expression of the BY55 protein has been shown to be tightly associated with NK and CD8+ T lymphocytes with cytolytic effector activity. To determine the function of this protein, we molecularly cloned BY55 cDNA. The cDNA sequence predicts a cysteine-rich, glycosylphosphatidylinositol-anchored protein of 181 amino acids with a single Ig-like domain weakly homologous to killer inhibitory receptors. Reduction and carboxyamidomethylation of immunoprecipitated BY55 gave a band of 27 kDa, whereas reduction alone led to an 80-kDa species, suggesting that BY55 is a tightly disulfide-linked multimer. RNA blot analysis revealed BY55 mRNAs of 1.5 and 1.6 kb whose expression was highly restricted to NK and T cells. BY55 was expressed on the CD56dim, CD16+ subset of NK cells, which have high cytolytic activity, but was not expressed and was not induced on the CD56bright, CD16-subset of NK cells, a subset with high proliferative, but low cytolytic, capacity. In human tissues, BY55 mRNA was expressed only in spleen, PBL, and small intestine (in gut lymphocytes). BY55 was expressed on all intestinal intraepithelial lymphocytes, which were predominantly CD3+TCRalpha/beta+CD4-CD8+CD11b+CD28-CD45RO+C D56-CD101+CD103+ (alphaEbeta7 integrin). In addition, BY55 was expressed on most CD8+CD28- peripheral blood T cells. These phenotypic relationships suggest that CD8+CD28+ precursor CTL may terminally differentiate into CD8+CD28-BY55+ effector CTL and that some of the peripheral blood CD8+CD28- subset may represent recirculation from mucosal epithelial immune sites. 相似文献
994.
SD Skaper M Floreani A Negro L Facci P Giusti 《Canadian Metallurgical Quarterly》1998,70(5):1859-1868
Cerebellar granule neurons maintained in medium containing serum and 25 mM K+ reliably undergo an apoptotic death when switched to serum-free medium with 5 mM K+. New mRNA and protein synthesis and formation of reactive oxygen intermediates are required steps in K+ deprivation-induced apoptosis of these neurons. Here we show that neurotrophins, members of the nerve growth factor gene family, protect from K+/serum deprivation-induced apoptotic death of cerebellar granule neurons in a temporally distinct manner. Switching granule neurons, on day in vitro (DIV) 4, 10, 20, 30, or 40, from high-K+ to low-K+/serum-free medium decreased viability by >50% when measured after 30 h. Treatment of low-K+ granule neurons at DIV 4 with nerve growth factor, brain-derived neurotrophic factor (BDNF), neurotrophin-3, or neurotrophin-4/5 (NT-4/5) demonstrated concentration-dependent (1-100 ng/ml) protective effects only for BDNF and NT-4/5. Between DIV 10 and 20, K+-deprived granule neurons showed decreasing sensitivity to BDNF and no response to NT-4/5. Cerebellar granule neuron death induced by K+ withdrawal at DIV 30 and 40 was blocked only by neurotrophin-3. BDNF and NT-4/5 also circumvented glutamate-induced oxidative death in DIV 1-2 granule neurons. Granule neuron death caused by K+ withdrawal or glutamate-triggered oxidative stress was, moreover, limited by free radical scavengers like melatonin. Neurotrophin-protective effects, but not those of antioxidants, were blocked by selective inhibitors of phosphatidylinositol 3-kinase or the mitogen-activated protein kinase pathway, depending on the nature of the oxidant stress. These observations indicate that the survival-promoting effects of neurotrophins for central neurons, whose cellular antioxidant defenses are challenged, require activation of distinct signal transduction pathways. 相似文献
995.
JE Max DA Robin SD Lindgren WL Smith Y Sato PJ Mattheis JA Stierwalt CS Castillo 《Canadian Metallurgical Quarterly》1997,36(9):1278-1285
OBJECTIVE: To extend findings regarding predictive factors of psychiatric outcome from the first to the second year after traumatic brain injury (TBI) in children and adolescents. METHOD: Subjects were children aged 6 to 14 years at the time they were hospitalized after TBI. The study used a prospective follow-up design. Assessments of preinjury psychiatric, behavioral, adaptive functioning, family functioning and family psychiatric history status were conducted. Severity of injury was assessed by standard clinical scales and neuroimaging was analyzed. The outcome measure was the presence of a psychiatric disorder, not present before the injury ("novel"), during the second year after TBI. RESULTS: Fifty subjects enrolled, and the analyses focused on 42 subjects followed at 24 months. Severity of injury, preinjury family function, and preinjury lifetime psychiatric history predicted the development of a "novel" psychiatric disorder present in the second year. CONCLUSION: These data suggest that there are children, identifiable through clinical assessment, at increased risk for "novel" psychiatric disorders in the second year after TBI. 相似文献
996.
WR Stevens PA Glazer SD Kelley TM Lietman DS Bradford 《Canadian Metallurgical Quarterly》1997,22(12):1319-1324
STUDY DESIGN: A retrospective review of 3450 spinal surgeries was performed. OBJECTIVES: To review ophthalmic complications and their etiologies, as well as treatments and outcomes, in patients who have undergone spinal surgery. SUMMARY OF BACKGROUND DATA: Ophthalmic complications after major spinal reconstructive surgery are rare and have not been adequately addressed in the orthopedic literature. METHODS: In a series of 3450 spinal surgeries at three institutions, the authors identified seven patients (incidence = 0.20%) whose postoperative course was complicated by loss of visual acuity. These perioperative ophthalmic complications included posterior optic nerve ischemia, occipital lobe infarcts, and central retinal vein thrombosis. Operative time, estimated blood loss, and medical history of peripheral vascular, cardiovascular, or ophthalmic disease were obtained from the charts, as were follow-up data. RESULTS: Three patients recovered completely, and one had partial return of visual function. In the remaining three patients, significant visual loss persisted. CONCLUSIONS: The risk of ophthalmic complications with spinal surgery has not been fully appreciated. Because ophthalmic complications in spinal surgery may be reversed with prompt recognition and intervention, it is important for clinicians to be aware of their possible occurrence. 相似文献
997.
HC Lin MC Yang YT Huang PC Yu MC Hou CY Hong SD Lee 《Canadian Metallurgical Quarterly》1997,54(1):16-23
Proteins that are actively secreted by Mycobacterium tuberculosis generate immune responses in the infected host. This has prompted the characterization of protein components of mycobacterial culture filtrates to develop subunit vaccines and immunodiagnostic reagents. Fractionation of filtrates of M. tuberculosis cultures has yielded an abundant protein called MPT63, which has an apparent molecular mass of 18 kDa. We report the molecular cloning and nucleotide sequence of the mpt63 gene, purification of recombinant MPT63 antigen from Escherichia coli cells, and serological characterization of MPT63. Nucleotide sequence analysis of mpt63 identified an open reading frame encoding a protein of 159 amino acids (aa) consisting of a 29-aa secretion signal peptide and a 130-aa mature MPT63 protein. Recombinant MPT63 protein, purified from E. coli cells, and native MPT63, purified from M. tuberculosis culture filtrates, were indistinguishable in serological assays. Thus, the recombinant protein constitutes a valuable reagent for immunological studies. MPT63 evoked humoral immune responses in guinea pigs infected with virulent M. tuberculosis by the aerosol route. The mpt63 gene is found only in species of the M. tuberculosis complex, as shown by DNA hybridization experiments. Moreover, polyclonal antibody against MPT63 does not cross-react with proteins of a common environmental mycobacterial species, Mycobacterium avium. The absence of cross-reactive epitopes makes MPT63 an attractive candidate as an M. tuberculosis complex-specific diagnostic reagent. In particular, evaluation of MPT63 as an M. tuberculosis complex-specific reagent for diagnostic skin testing is under way. 相似文献
998.
999.
Active physician involvement and leadership in their accreditation process can produce a cubic win for patients, payors, and providers. For health care quality to improve and everyone win, physicians need to understand the accountability system, the what and why of data collection, and be involved in short- and long-term performance assessments. 相似文献
1000.
The Fetal ALZ-50 Reactive Clone 1 (FAC1) gene is expressed at high levels during brain development and is re-expressed in some neurodegenerative diseases. It is hypothesized that FAC1 functions during neuronal differentiation and may play an active role in neuritic re-organization following brain injury. We have previously employed the entorhinal cortex lesion model to examine reactive synaptogenesis and plasticity in the hippocampal dentate molecular layer following denervating lesion. We now report re-expression of FAC1 in the molecular layer (ML) of the dentate gyrus following entorhinal cortex (ERC) lesion. Denervated hippocampi (2,6,15, and 30 days post ERC lesion) were stained with anti-FAC1 antibody and processed for both light and electron microscopy. FAC1 was rapidly re-expressed (by 2 days) following ERC lesion, paralleling our previous observations with embryonic neural cell adhesion molecule (eN-CAM). Like eN-CAM, FAC1 expression was restricted to the denervated outer ML (OML) at 2 days post lesion. Analysis of later time points revealed an elimination of FAC1 immunostaining at the inner ML (IML)/(OML) interface as IML sprouts into the denervated zone. Image analysis confirmed the diminution of FAC1 staining in the OML as the IML sprouted into the denervated zone and revealed that FAC1 expression paralleled the temporal and spatial expression of eN-CAM following ERC lesion. Ultrastructural analysis of FAC1 staining at 6 and 30 days post lesion revealed immunoreactive profiles with the morphological characteristics of dendrites and cytoplasmic staining of granule cell perikarya. Dendritic staining was localized to the denervated OML and was not associated with any other neuropil profiles within this zone; IML staining was rare and restricted to large apical dendrites proximal to granule cell perikarya. These findings suggest that re-expression of FAC1 in the denervated OML is a rapid response to brain injury and may be important in synaptic plasticity and sprouting. 相似文献