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151.
Characterization of recombinant human fibroblast growth factor (FGF)-10 reveals functional similarities with keratinocyte growth factor (FGF-7) 总被引:1,自引:0,他引:1
A newly identified member of the fibroblast growth factor (FGF) family, designated FGF-10, is expressed during development and preferentially in adult lung. The predicted FGF-10 protein is most related to keratinocyte growth factor (KGF, or FGF-7). The latter is unique among FGFs in that it binds and signals only through the FGF receptor (FGFR2b) isoform KGF receptor (KGFR) expressed specifically by epithelial cells. In order to examine the biological and biochemical properties of human FGF-10, we isolated the cDNA and expressed its encoded protein in bacteria. The recombinant protein (rFGF-10) was a potent mitogen for Balb/MK mouse epidermal keratinocytes with activity detectable at 0.1 nM and maximal at around 5 nM. Within this concentration range, FGF-10 did not stimulate DNA synthesis in NIH/3T3 mouse fibroblasts. rFGF-10 bound the KGFR with high affinity comparable to that of KGF, and did not bind detectably to either the FGFR1c (Flg) or FGFR2c (Bek) receptor isoforms. The mitogenic activity of FGF-10 could be distinguished from that of KGF by its different sensitivity to heparin and lack of neutralization by a KGF monoclonal antibody. These results indicate that FGF-10 and KGF have similar receptor binding properties and target cell specificities, but are differentially regulated by components of the extracellular matrix. 相似文献
152.
We have seen a case of hyperventilation which appeared to have been caused by contact with an insecticide. Pathophysiology, epidemiology and treatment are discussed. Familiarity with the clinical symptoms greatly facilitate diagnosis, especially in emergency situations. 相似文献
153.
After in vivo inoculation with abl/myc- and raf/myc-containing retroviruses, BALB/c mice predominantly develop late stage B cell tumors (plasmacytomas) and less frequently develop earlier B-lineage tumors while DBA/2 mice do not develop B-lineage tumors. We have investigated the in vitro tumorigenic potential of these viruses using cultured normal pre-B cell lymphocytes from both BALB/c and DBA/2 mice. Interestingly, both viruses infect cultured pre-B lymphocytes from both mouse strains. Following infection, IL-7 dependent pre-B cells become independent of normal in vitro growth requirements within 24 h and can rapidly form in vivo pre-B lymphomas in both mouse strains. Mechanisms mediating loss of IL-7 dependence are different depending on whether the raf or abl gene is present in myc-containing viruses. IL-7 JAK-STAT signaling is constitutively active in abl/myc induced pre-B cell tumors. In contrast, IL-7 JAK-STAT signaling is not constitutive in raf/myc induced pre-B cell tumors, demonstrating that subversion of this component of IL-7 signal transduction is not obligatory for pre-B cell transformation or loss of IL-7 dependence. 相似文献
154.
RJ O'Hara J Greenman AW MacDonald KM Gaskell KP Topping GS Duthie MJ Kerin PW Lee JR Monson 《Canadian Metallurgical Quarterly》1998,4(8):1943-1948
Interleukin 12 (IL-12) is a heterodimeric cytokine that has been demonstrated to have a major role in stimulating a cell-mediated antitumor response. IL-10, a product of T helper 2 lymphocytes, is its most potent inhibitor. The aim of this study was to investigate whether patients with colorectal cancer had an imbalance in production of IL-12 and IL-10 preoperatively, and whether this was associated with advanced disease at surgery. Blood was obtained before surgery from 60 patients with colorectal cancer and from 30 controls. Peripheral blood mononuclear cells were incubated with Staphylococcus aureus Cowan's strain 1 in vitro for 24 h to assess IL-12 expression after stimulation, and serum was used for IL-10 measurement. IL-12 and IL-10 levels were assessed by ELISA. A single pathologist staged the tumors according to the tumor-node-metastasis (TNM) and Dukes' classifications. Patients with colorectal cancer had significantly lower levels of IL-12 (P <0.001) and higher levels of IL-10(P = 0.004) compared to controls. In addition, lower levels of IL-12 were detected in those patients who were node positive (P<0.05), had Dukes' C lesions (P < or = 0.001), and T3 or T4 lesions (P<0.033) when compared to controls. Patients with Dukes' B and C lesions (P<0.01) and T3 and T4 lesions (P<0.05) also had higher levels of IL-10 compared to controls. This study is the first to demonstrate that patients with colorectal cancer have decreased IL-12 production and increased serum IL-10. This suggests an impaired T helper 1 cell-mediated antitumor response and provides some justification for exogenous IL-12 therapy or anti-IL-10 therapy in these patients. 相似文献
155.
PW Pisters 《Canadian Metallurgical Quarterly》1998,5(5):464-472
Various aspects of epilepsy, including its evolution, were studied in 78 children with mental retardation in a prospective 5-year (1989-1994) follow-up study. Level of mental retardation was moderate or even more severe (IQ < 50) in 83% of children, and 56% suffered from significant cerebral palsy. Epilepsy remained uncontrolled in 28% of cases, 2-year remission was achieved by 26%, and mortality was 12% during the study period. Associated cerebral palsy was the most important single risk factor for severe epilepsy, and several handicaps seemed to have a strong multiplicative effect. Complexity of epilepsy in children with mental retardation was reflected by the evolutionary features described. 相似文献
156.
M Sluijter H Faden R de Groot N Lemmens WH Goessens A van Belkum PW Hermans 《Canadian Metallurgical Quarterly》1998,36(8):2248-2253
Pneumococcal colonization was studied in 19 children monitored from birth through the age of 2 years. For this purpose, pneumococcal isolates were characterized by capsular typing, restriction fragment end labeling (RFEL), and penicillin-binding protein (PBP) genotyping. Fifty-eight isolates were collected and were found to belong to 10 capsular types, 31 RFEL types, and 7 PBP genotypes. Thirty-nine percent of the isolates had reduced susceptibility to penicillin. All seven highly resistant strains (MICs, > 1 microgram/ml) were identical to the pandemic clone 23F. Children were culture positive between one and eight times at 13 scheduled visits. Although the infants were frequently recolonized with different strains, colonization with one particular strain often persisted for several months. Isolation of a previously detected capsular type was common, and the chromosomal homogeneity tended to be high when it occurred. Horizontal transfer of capsular genes between strains of different RFEL types was demonstrated in one child. The ecological advantage of transfer of capsular genes is unclear unless survival of the organism on a mucosal surface may be linked to immunoprotective pressure against particular capsular types. 相似文献
157.
158.
OBJECTIVE: To apply clinical effectiveness estimates of interactive, neural network-assisted (INNA) screening to economic cervical cancer screening models to assess the economic impact of using this technology. STUDY DESIGN: Estimates of the sensitivity of INNA screening were drawn from a recently completed comprehensive synthesis of the INNA literature and applied to the Computer Model for Designing CANcer ConTROL Programs-based Cervical Cancer Screen economic model. The economic analysis was conducted from a modified payer perspective using costs borne by payers combined with patient deductibles and copayments. Costs of treating cervical cancer were updated to 1997 values using the medical care component of the Consumer Price Index. The model was run for a cohort of women starting at age 20 and screened on a triennial schedule through age 75. RESULTS: In the primary analysis (sensitivity of unassisted manual examination assumed to be 85%), the ratios found in this investigation varied from approximately $35,000 to $80,000 per life year saved, with the preponderance of ratios < $50,000 per life year saved. These results were sensitive to estimates of sensitivity of unassisted manual screening but not to estimates of treatment costs. CONCLUSION: This investigation applied accuracy data on INNA rescreening to a model of the cost-effectiveness of cervical cancer screening. The results support the use of INNA rescreening as an appropriate expenditure of resources to identify missed cases of cervical epithelial abnormalities and potential cervical cancer. 相似文献
159.
160.