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871.
A cytogenetic survey was carried out on 200 patients with mental retardation and multiple congenital anomalies, and on 200 normal adult controls. Patients with a known syndrome were excluded from the survey. Chromosome analyses were carried out on 'blind-coded' slides using the ASG banding technique as the routine stain. After the initial analyses (at least 15 cells per person) the slides were decoded, destained and reused for C and Q band polymorphism studies. Five major chromosome abnormalities were detected in the patient group during the survey. They included three patients with de novo, apparently balanced, reciprocal translocations, karyotypes 46,XY,rcp(3;16)(q21;p12); 46,XX,rcp(5;8)(p15;q22); and 46,XX,rcp(5;12)(p11;q24); one with karyotype 47,XX,+mar and one with karyotype 46,XX,der(13),t(13;?)(q34;?). One additional patient whose karyotype in lymphocytes was 46,XX,inv(9)(p11;q13) was found to have a mosaic karyotype 46,XX,inv(9)(p11;q13)/46,XX,inv(9) (p11;q13), der(12),t(12;?)p13;?) in cultured skin fibroblasts. None of the 200 controls had a major chromosome abnormality. From the combined results of this and previous surveys it is now apparent that about 6.2% of the unclassifiable mentally retarded patients with three or more congenital anomalies and about 0.7% of the controls reveal major chromosome abnormalities. 相似文献
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RC Hickson WW Heusner WD Huss DE Jackson DA Anderson DA Jones AT Psaledas 《Canadian Metallurgical Quarterly》1976,8(3):191-195
The practice of sequential incubation in radio-immunoassay of TSH improves the sensitivity and precision without affecting the specificity compared with the method using simultaneous incubation of the constituents of the radio-immunological reaction. The determination of basic levels of TSH is more sensitive and more precise. 相似文献
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It is generally assumed that folding intermediates contain partially formed native-like secondary structures. However, if we consider the fact that the conformational stability of the intermediate state is simpler than that of the native state, it would be expected that the secondary structures in a folding intermediate would not necessarily be similar to those of the native state. beta-Lactoglobulin is a predominantly beta-sheet protein, although it has a markedly high intrinsic preference for alpha-helical structure. We have studied the refolding kinetics of bovine beta-lactoglobulin using stopped-flow circular dichroism and find that a partly alpha-helical intermediate accumulates transiently before formation of the native beta-sheets. The present results suggest that the folding reaction of beta-lactoglobulin follows a non-hierarchical mechanism, in which non-native alpha-helical structures play important roles. 相似文献
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The protective effect of breastfeeding against infantile diarrhoea may be less pronounced in areas with modern water supply and sanitation facilities. This finding raises the question whether protection by breastfeeding against infantile diarrhoea in developing countries will decline with improvement in water supply and sanitation. To address this question a historical cohort study of the associations between feeding modes and diarrhoea incidence and severity in children aged 0-14 months at baseline was done in Al Ain city, United Arab Emirates. In this city in a newly developed country, modern water supply and sanitation facilities have become available to everyone during the last two decades. During three months of follow-up of 249 children, the nonbreastfed had more diarrhoea than did the partly breastfed, who in turn had more diarrhoea than did the fully breastfed. After multivariate adjustment, this dose-response effect was consistent for three measures of diarrhoeal morbidity in each child: occurrence or non-occurrence of incidence episodes, number of episodes, and total severity score. However, significant differences were seen only between the nonbreastfed and fully breastfed subgroups. These results indicate that in Al Ain, despite the universal access to modern water supply and sanitation facilities, breastfeeding plays an important role in reducing the incidence and severity of infantile diarrhoea. This observation is particularly important given the growing concern that, as an unwanted effect of 'modernisation', breastfeeding is on the decline in Al Ain and comparable populations elsewhere. 相似文献