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991.
MR Rozas García 《Canadian Metallurgical Quarterly》1998,21(241):65-68
Maternal breastfeeding is a physiological process which almost all women are capable of performing. Some special circumstances, such as the adoption of a baby, the problems a baby has sucking, or the temporary interruption of milk secretion, can cause difficulties and this is when the use of the so-called breastfeeding supplements is warranted. We describe the SNS supplementary nutritional system so that health professionals may understand its characteristics, use, and applications and therefore be able to offer women the necessary advise and assistance during breastfeeding. 相似文献
992.
JS Gerritsma C van Kooten AF Gerritsen AM Mommaas LA van Es MR Daha 《Canadian Metallurgical Quarterly》1998,6(3):208-216
PURPOSE: The clinical importance of the edge lift of rigid contact lenses is often neglected, possibly due to previous difficulties in its measurement. A new method of measuring axial edge lift (AEL) and radial edge lift (REL) using standard contact lens verification equipment, such as an optical spherometer, a thickness gauge, and contact lens V gauge, is described. METHODS: The technique was validated for trueness (accuracy) and precision (repeatability) by measuring the edge lift of a number of monocurve lenses, manufactured both with and without a normal edge finish. RESULTS: Edge lift was measured to an accuracy of 0.01 mm. CONCLUSIONS: As long as a mean of eight independent measurements of back optic zone radius (BOZR), sagitta, and one measurement of center thickness are taken, the pillar and collar technique is capable of producing accurate and repeatable measurements of the edge lift of a rigid contact lens. 相似文献
993.
G van Zandbergen C van Kooten NK Mohamad TJ Reterink JW de Fijter JG van de Winkel MR Daha 《Canadian Metallurgical Quarterly》1998,13(12):3058-3064
BACKGROUND: Primary IgA nephropathy (IgAN) is associated with elevated levels of circulating IgA and is characterized by deposition of primarily IgA1 in the renal mesangium. It has not yet been clarified which mechanisms govern the deposition of IgA1 in the mesangium. One of the factors which may play a role in trapping of IgA in the mesangial area is the interaction of IgA with specific IgA receptors (Fc alphaR, CD89) on the mesangial cells. METHODS: In the present study IgA derived from patients with IgAN and controls was investigated for its interaction with human CD89, expressed on the surface of the murine B cell line IIA1.6. RESULTS: IgA binding to CD89 expressing cells was specific, concentration dependent and binding of dIgA and pIgA occurred in a more efficient fashion than that of mIgA. IgA binding to CD89 directly from serum of patients compared to controls showed no significant difference. However these experiments are affected by differences in IgA concentration and combinations of different sizes of IgA. Using purified fractions of mIgA, dIgA, and pIgA isolated from serum, a significantly reduced binding of mIgA to CD89 from patients compared to controls was observed. Finally, the binding of aIgA2 to CD89 was less inhibited using mIgA from patients with IgAN compared to controls. CONCLUSIONS: The reduced binding of mIgA to CD89 seems to contradict a direct role for CD89 in deposition of IgA. However reduced binding of mIgA to CD89 may affect IgA clearance, leading to higher serum IgA. Furthermore, since it has been demonstrated that mIgA can interfere with binding of di- and pIgA, CD89 could still contribute to pIgA deposition in the mesangial area. 相似文献
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We recently encountered a patient with severe flatulence who previously had been subjected to innumerable diagnostic tests and ineffective therapies based on the belief that his rectal gas was produced in the colon. Analysis of three flatus samples demonstrated that nitrogen (N2) was the predominant flatus gas whereas the three gases produced in the gut (CO2, H2 [hydrogen], and CH4 [methane]) comprised <16% of rectal gas. This result plus a series of other diagnostic tests clearly indicated that the patient's flatus was derived almost entirely from swallowed air. Based on this case, the present report summarizes available data on excessive flatulence and suggests a rational approach to the patient complaining of this problem. Particular emphasis is placed upon a sequential strategy consisting of: 1) a count of flatus passages to determine if the subject truly is abnormal (normal: <20 passages/day); 2) an analysis of flatus to determine if the flatus originates from swallowed air (predominantly nitrogen) or intraluminal production (predominantly CO2, H2, and CH4); and 3) treatment based upon the origin of the rectal gas. 相似文献
1000.
DS Keeney C Skinner JB Travers JH Capdevila LB Nanney LE King MR Waterman 《Canadian Metallurgical Quarterly》1998,273(48):32071-32079
The novel cytochrome P450, CYP2B19, is a specific cellular marker of late differentiation in skin keratinocytes. CYP2B19 was discovered in fetal mouse skin where its onset of expression coincides spatially (upper cell layer) and temporally (day 15.5) with the appearance of loricrin-expressing keratinocytes during the stratification stage of fetal epidermis. CYP2B19 is also present postnatally in the differentiated keratinocytes of the epidermis, sebaceous glands, and hair follicles. CYP2B19 mRNA is tightly coupled to the differentiated (granular cell) keratinocyte phenotype in vivo and in vitro. In primary mouse epidermal keratinocytes, it is specifically up-regulated and correlated temporally with calcium-induced differentiation and expression of the late differentiation genes loricrin and profilaggrin. Recombinant CYP2B19 metabolizes arachidonic acid and generates 14,15- and 11, 12-epoxyeicosatrienoic (EET) acids, and 11-, 12-, and 15-hydroxyeicosatetraenoic (HETE) acids (20, 35, 18, 7, and 7% of total metabolites, respectively). Arachidonic acid metabolism was stereoselective for 11S,12R- and 14S,15R-EET, and 11S-, 12R-, and 15R-HETE. The CYP2B19 metabolites 11,12- and 14,15-EET are endogenous constituents of murine epidermis and are present in similar proportions to that generated by the enzyme in vitro, suggesting that CYP2B19 might be the primary enzymatic source of these EETs in murine epidermis. 相似文献