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891.
892.
893.
MS Foster A Rodabough TM Dayton EM Melko SS Szegedi EC Niederhoffer 《Canadian Metallurgical Quarterly》1993,15(6):996-8, 1000, 1002
The strictly anaerobic, extremely thermophilic methanogens, Methanobacterium thermoautotrophicum Marburg and M. thermoautotrophicum delta H, have been cultivated in liquid culture and on solid medium in screw-top bottles, which permit continuous monitoring of the growth of the microorganisms. We have been able to routinely grow methanogens in medium containing bicarbonate, TRIS or 4-morpholinepropanesulfonic acid (MOPS) buffers and three different sulfur sources (sulfide, sulfite and thiosulfate) at temperatures up to 70 degrees C and at pressures up to 35 psi while monitoring cell density or colony formation. 相似文献
894.
The Bio 14.6 Cardiomyopathic Syrian Hamster (CMH) has an autosomal recessive disease characterized by intracellular calcium overload, cardiac and skeletal myopathies and premature death from congestive heart failure. Early treatment of these animals with the calcium antagonist, verapamil (V), prevents the development of the disease. We have previously provided evidence supporting a specific defect in the ryanodine-sensitive SR calcium release channel (SRCRC) in CMH. We now provide physiologic and biochemical evidence that V modulates SRCRC. Papillary muscles prepared from F1B control hamsters (F1B) revealed an enhanced inotropic responsiveness to V and ryanodine (R) with age, not seen with CMH. CMH papillary muscles demonstrated paradoxical positive inotropic effects of V and R not shared with F1B. The positive inotropic effects of V and R were not additive. V enhanced the affinity (decreased KD) of [3H]ryanodine binding to cardiac membranes. Thus, V may prevent the overt manifestations of genetic disease in CMH by modulating a defective ryanodine-sensitive SR release channel. 相似文献
895.
MS Henner PE Shapiro JH Ritter DJ Leffell MR Wick 《Canadian Metallurgical Quarterly》1995,17(5):465-470
Interleukin-1 receptor antagonist (IL-1ra) competes with IL-1 for binding of the IL-1 receptor, but does not elicit a cellular immune response. This study was designed to evaluate the effectiveness of IL-1ra in the immune and inflammatory responses to rat heart allografts. Experimental design was as follows: Group I HTx was syngeneic, BN to BN. The remaining groups were DA (RT 1a) to BN (RT 1n) allogeneic HTx. Group II was transplanted without immunosuppression. Group III received a low-dose IL-1ra regimen via osmotic pump into the peritoneum. Group IV recipients were similarly treated with a higher dose IL-1ra regimen. Group V rats received subtherapeutic cyclosporine (CsA) therapy while Group VI was treated with both CsA and low-dose IL-1ra. Group I rats survived indefinitely. Group II rats rejected their grafts at 5.33 +/- 1.37 days. Group III grafts survived for 7.16 +/- 0.48 days, and Group IV grafts for 8.16 +/- 0.75 days, both significantly longer than in Group II (P < 0.01). Group V animals treated with low-dose CsA had graft survival of 7.7 +/- 1.6 days, but combined therapy with CsA and IL-1ra in Group VI yielded significantly prolonged graft survival of 17.2 +/- 1.3 days (P < 0.0001). Histologic examination in treated recipients revealed delayed appearance of mononuclear cell infiltration. IL-1ra-treated recipients all demonstrated significantly reduced numbers of graft-infiltrating leukocytes; all phenotype subsets were equally affected. This study demonstrates the effectiveness of IL-1ra, in combination with low-dose CsA, in reducing the inflammatory response and rejection in the transplant setting. 相似文献
896.
Potentially, antiviruses that interfere with HIV propagation could be used as AIDS therapy. If problems associated with HIV recombination and the dynamics of the interactions between HIV and antivirus can be resolved by an appropriate design, an antivirus might defer or prevent the development of AIDS, and might benefit AIDS patients. 相似文献
897.
898.
PK Koskinen MS Nieminen SP Mattila PJ H?yry IT Lautenschlager 《Canadian Metallurgical Quarterly》1993,55(3):547-551
Previous studies have demonstrated that CMV-specific antigens detected from peripheral blood leukocytes correlate with active CMV infection in transplant patients. However, the clinical diagnosis of CMV infection is difficult, and the significance of a positive blood finding is unclear, while CMV antigenemia and viremia may also occur in asymptomatic patients. To investigate the clinical significance of CMV antigenemia after heart transplantation, 68 heart allograft recipients were monitored weekly. Altogether 501 blood specimens were analyzed. CMV was demonstrated in blood leukocytes by a monoclonal antibody and immunoperoxidase staining, and the antigenemia level was expressed as CMV positive cells/50,000 leukocytes. CMV antigenemia occurred in 28/68 patients, and 12 of them developed a symptomatic infection. Of all blood specimens 88/501 were CMV positive, and 30 of them related to the clinical manifestation of CMV. When antigenemia level exceeded > 100/50,000, a significant correlation between antigenemia and CMV-related clinical manifestation was reached (P < 0.001). Of the 28 antigenemia positive patients 16 never developed any clinical signs of CMV infection. Their maximal antigenemia level was low (median 23, range 30-90) compared with those with clinical manifestation (median 500, range 30-1000) (P < 0.002). In conclusion, high antigenemia levels (> 100/50,000) correlate with clinical manifestations of CMV infection. Patients with lower levels (< 100/50,000) do not necessarily ever develop a symptomatic infection. Quantitative monitoring of CMV antigenemia may, thus, be helpful in the clinical diagnosis of CMV infection in heart transplant patients. 相似文献
899.
MS Treuth GR Hunter T Kekes-Szabo RL Weinsier MI Goran L Berland 《Canadian Metallurgical Quarterly》1995,78(4):1425-1431
The purpose of this study was to examine the effects of a total body strength-training program on changes in total and regional body composition, in particular intra-abdominal adipose tissue (IAAT), in older women. Fourteen healthy older women (mean age 67 +/- 1 yr) exercised 3 times/wk for 16 wk. Strength was assessed by one-repetition maximum tests, with training intensity gradually increased to approximately 67% of one repetition maximum. Body composition was measured by hydrodensitometry and regional body composition was measured by computed tomography. Strength was significantly increased in the upper (51%) and lower body (65%). There was no significant change in body weight (64.4 +/- 2.7 vs. 64.2 +/- 2.7 kg), total body fat (38.7 +/- 1.4 vs. 38.0 +/- 1.6%) or fat-free mass (39.7 +/- 1.0 vs. 40.0 +/- 0.9 kg). However, after ST, there were significant reductions in IAAT (143.9 +/- 13.3 vs. 130.0 +/- 12.4 cm2), the IAAT-to-subcutaneous adipose tissue ratio (0.48 +/- 0.04 vs. 0.44 +/- 0.04), and midthigh subcutaneous adipose tissue (141.7 +/- 11.5 vs. 133.6 +/- 10.8 cm2) and an increase in midthigh muscle (52.9 +/- 2.6 vs. 58.0 +/- 2.0 cm2) (all P < 0.05). In conclusion, significant reductions in IAAT and an increase in strength and muscle area were observed after a strength-training program in healthy older women. These changes may be important in preventing the negative health outcomes associated with the age-related increase in intra-abdominal obesity. 相似文献
900.
The subcutaneous absorption and consequent tissue distribution of interferon g was studied in an anaesthetized rat model. Interferon g showed a biphasic disappearance profile from a solution in a subcutaneous absorption cell. Both the initial rapid distribution phase and slower removal phase followed first order kinetics. The steady-state clearance of interferon g from the cell was 1.41 +/- 0.38 x 10(-3) mL min-1, and the absorption half-life (t1/2) was 3.8 +/- 1.1 h (n = 4). Noradrenaline did not significantly alter either the clearance or absorption of interferon g (1.18 +/- 0.44 x 10(-3) mL min-1, P > 0.05, absorption t1/2 4.96 +/- 1.9 h, P > 0.05). Given that the clearance of smaller solutes, such as tritiated water, is significantly reduced when noradrenaline is coadministered, it is suggested that interferon g is removed via the lymphatic system rather than by the local blood supply. The amount of interferon g recovered in the plasma, urine and muscle is minimal relative to other solutes where the recovery is almost complete. 相似文献