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91.
92.
This paper describes a study of the physico-chemical and radioimmunological properties of three antialdosterone antisera which permitted practical conclusions to be drawn. By its high degree of specificity, anti-aldo-3-oxime-BSA constitutes the most useful antiserum for the clinical assay of aldosterone. The principal advantage of this antiserum is that it allows both urinary and blood aldosterone radioimmunoassay without the necessity of including a chromatographic step. No problems arise with the blanks. This work also includes the study of two anti-deoxycorticosterone antisera. The aldosterone and deoxycorticosterone values, obtained from normal subjects under various physiological conditions, are in agreement with the values given in the literature. 相似文献
93.
94.
Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes. 相似文献
95.
The outdating of units of blood can be reduced by decreasing the amount of time they spend in an assigned or crossmatched status. This reduction can be achieved in a hospital by establishing a maximum surgical blood order schedule (MSBOS) which reduces the excessive number of units of blood crossmatched preoperatively for patients undergoing elective surgery. The various steps which occurred in the development of a MSBOS in a large general hospital are detailed and the projected reduction in the number of crossmatched units which can be achieved with the MSBOS is illustrated. illustrated. The projected number of units of blood transfused to patients during their hospitalization for 50 common primary surgical procedures in the United States during 1974 is presented as a basis for defining maximum blood orders for each procedure. 相似文献
96.
应用一种新的近净成型技术——凝胶注模成型技术,成功制备大尺寸、复杂形状医用多孔钛人造骨替代材料,并研究了凝胶注模成型工艺参数对浆料流动特性、坯体强度及烧结体孔隙、力学性能的影响。研究结果表明:预混液中有机单体的浓度、单体/交联剂比例以及固相含量是决定钛粉浆料表观粘度、Gelcasting坯体强度的重要参数;对于医用多孔钛植入材料的凝胶注模成型工艺,适合的顸混液单体浓度为30%(质量分数),单体,交联剂比例为120:1,浆料固相含量为34%(体积分数);1100℃保温1.5h是凝胶注模成型多孔钛较为适合的烧结工艺路线;所制得孔隙度46.5%、开孔隙度40.7%多孔钛的抗压强度158.6MPa、弹性模量8.5GPa,与自然骨基本匹配,适合作为人造骨替代材料。 相似文献
97.
VM Reddy DB McElhinney HA Rajasinghe JR Liddicoat K Hendricks-Munoz JR Fineman FL Hanley 《Canadian Metallurgical Quarterly》1999,117(2):343-351
BACKGROUND: Fetal cardiac bypass causes placental dysfunction, characterized by increased placental vascular resistance, decreased placental blood flow, hypoxia, and acidosis. Vasoactive factors produced by the vascular endothelium, such as nitric oxide and endothelin 1, are important regulators of placental vascular tone and may contribute to this placental dysfunction. METHODS: To investigate the role of the vascular endothelium in placental dysfunction related to fetal cardiac bypass, we studied 3 groups of fetal sheep. In the first group (n = 7) we determined placental hemodynamic responses before and after bypass to an endothelium-dependent vasodilator (acetylcholine), an endothelium-independent vasodilator (nitroprusside), and endothelin 1. In the second group (n = 8) a nonspecific endothelin receptor blocker (PD 145065) was administered and placental hemodynamic values were measured before and after bypass. In the third group (n = 5) endothelin 1 levels were measured before and after bypass. RESULTS: Before fetal cardiac bypass exogenous endothelin 1 decreased placental blood flow by 9% and increased placental resistance by 9%. After bypass endothelin 1 decreased placental flow by 47% and increased resistance by 106%. There was also a significant attenuation of the placental vascular relaxation response to acetylcholine after bypass, whereas the response to nitroprusside was not significantly altered. In fetuses that received the PD 145065, placental vascular resistance increased significantly less than in control fetuses (28% versus 62%). Similarly, placental blood flow decreased significantly more (from 6. 3 +/- 3.1 to 28.3 +/- 10.4 pg/mL; P =.01) in control fetuses than in fetuses receiving PD 145065 (33% versus 20%). Umbilical venous endothelin 1 levels increased significantly in fetuses exposed to fetal bypass but did not change in control fetuses. CONCLUSIONS: The basal endothelial regulatory mechanisms of placental vascular tone were deranged after fetal cardiac bypass. Endothelin receptor blockade, which substantially reduced postbypass placental dysfunction, and other interventions aimed at preserving endothelial function may be effective means of optimizing fetal outcome after cardiac bypass. 相似文献
98.
Coryneform bacteria and yeasts of 21 brick cheeses from six German dairies, produced by using undefined ripening cultures, were identified. Arthrobacter nicotianae, Brevibacterium linens, Corynebacterium ammoniagenes, Corynebacterium variabilis and Rhodococcus fascians were found in significant numbers. Out of 148 coryneform isolates 36 could not be identified at the species level. With the exception of a large rennet cheese, the coryneform microflora of rennet and acid cured cheeses were similar, but the cheeses had clearly different yeast populations. Debaryomyces hansenii and Galactomyces geotrichum prevailed in rennet cheeses while Kluyveromyces marxianus and Pichia membranaefaciens were the main species found in acid cured cheese. The dominance of Yarrowia lipolytica probably indicates an improper yeast population, resulting in poor cheese quality. Some of the species identified are potential candidates for designing a defined ripening culture for rennet red smear cheese. 相似文献
99.
D Mack J Riedewald H Rohde T Magnus HH Feucht HA Elsner R Laufs ME Rupp 《Canadian Metallurgical Quarterly》1999,67(2):1004-1008
Hemagglutination of erythrocytes is a common property of Staphylococcus epidermidis strains, which is related to adherence and biofilm formation and may be essential for the pathogenesis of biomaterial-associated infections caused by S. epidermidis. In three independent biofilm-producing, hemagglutination-positive S. epidermidis isolates, interruption of the icaADBC operon essential for polysaccharide intercellular adhesin (PIA) synthesis by Tn917 insertions led to a hemagglutination-negative phenotype. An immunoglobulin G fraction of antiserum to PIA greatly reduced hemagglutination. Purified PIA led to a 64-fold decrease of hemagglutination titers of these strains; however, it did not mediate hemagglutination by itself. These observations define PIA as the hemagglutinin of S. epidermidis or at least as its major functional component. 相似文献
100.