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51.
The alleged association between induced abortion and breast cancer is one of the most controversial and important questions in women's health today. To help clinicians provide appropriate counseling, we reviewed both the primary data and review articles on this topic. We identified the studies and reviews by using Medline and the reference lists of articles and texts. We then used the U.S. Preventive Services Task Force rating system to evaluate the evidence. Many case-control studies have addressed this question, but their results have been inconsistent. Persistent problems in the case-control studies include selection of an appropriate control group, recall bias (under-reporting of induced abortion by controls), and confounding by other risk factors. Two recent, large cohort studies, which are less susceptible to bias, showed either protection or no effect on breast cancer risk from an induced abortion. At present, level II-2 evidence (cohort and case-control studies) supports a class B recommendation (fair evidence) that induced abortion does not increase a woman's risk of breast cancer later in life.  相似文献   
52.
Surface plasmon resonance (SPR) biosensors were constructed on miniature integrated sensors. Recognition elements were attached to the sensor surface using a gold-binding repeating polypeptide. Biosensors with fluorescyl groups attached to their surfaces were functional for at least 1 month of daily use with little decrease in response to the binding of an anti-fluorescyl monoclonal antibody. The coupling of protein A to the gold-binding polypeptide on the sensor surface enabled the biosensor to detect the binding of antibodies to the protein A and provided a sensor with convertible specificity. The system described herein provides a simple and rapid approach for the fabrication of highly specific, durable, portable and low cost SPR-based biosensors.  相似文献   
53.
The effects of method of hydrolysis and source of sorghum sprout (sorghum cultivar) on the nitrogen and mineral contents of acid digests from three commercial malting varieties of sorghum were assessed. The mineral and nitrogen contents and constituents of the digests varied significantly (p < 0.05) with respect to the method of digestion, sprout source and the pair-wise interaction of the two factors. Higher digest nitrogen, in both ICSV 400 and SK 5912, was supported by acid digestion in the autoclave while reflux digestion produced higher nitrogen in KSV 8. Of all the digests, those from ICSV 400 (both reflux and autoclave) displayed the best balance of yeast-essential acids as well as superior growth-promoting activity. In their growth-producing activity, the digests also compared very favourably with seven commercial nitrogenous bases used industrially for yeast cultivation. Results suggest that sorghum sprout acid digests are good alternative sources for nitrogen and mineral nutrients in media for microbial cultivation.  相似文献   
54.
Gender differences in patterns of relationship violence were investigated in a sample of 356 men and 351 women. Respondents reported on their receipt and perpetration of violent acts in the year prior to the survey. Men and women, respectively, reported similar 1-yr prevalence rates of husband-to-wife violence and wife-to-husband violence. However, differential gender patterns of reporting were identified. On average, men reported that they and their female partners were equally likely to engage in violent acts and to initiate violent conflicts. In contrast, women reported lower levels of victimization than perpetration of violence, and they reported less male-only and male-initiated violence than did men. The majority of respondents in violent relationships reported a pattern of violence that was bidirectional, minor, infrequent, and not physically injurious. The discussion focuses upon the meaning of gender differences in reports of relationship violence, and the existence of distinct patterns of violence within intimate relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
Practical models of competition among power generators who possess market power have generally had to use simplified models of transmission costs and constraints in order to be tractable. In particular, the linearized dc load flow model has been popular in complementarity and other types of oligopoly models. In this paper, we show how such models can be generalized to include quadratic losses, controllable DC lines, and phase shifting transformers. These generalizations preserve convexity of the feasible region, a property that facilitates computation and proof of solution uniqueness and existence. Piecewise and successive linearization formulations are also provided that allow consideration of nonlinear losses in models that require linear constraints. A simple six-bus example illustrates the application of these generalizations. In that example, the impact of losses on prices is much greater under strategic behavior than under competition. Large-scale applications of these approaches to markets in western North America and the European Union illustrate how inclusion of nonlinear losses and controllable DC lines can affect estimates of prices, flows, and economic efficiency indices resulting from oligopoly models.   相似文献   
56.
Viewpoint     
Journal of the American Oil Chemists' Society -  相似文献   
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Coronary heart disease (CHD) is a multifactorial disease and CHD risk should be estimated by assessing all cardiovascular risk factors simultaneously. Simply adding up the number of factors with 'at risk' values fails to identify high-risk subjects with multiple risk factors at moderately elevated values. A more efficient approach is to use a quantitative multivariate risk score. A number of overseas studies have produced CHD risk scoring systems for men. There are few risk scores developed for women and no CHD risk scores have been developed from Australian data. This study used data on CHD risk factors and morbidity/mortality follow-up for the 1978 Busselton Health Survey participants to provide age-specific estimates of absolute risk of CHD hospitalisation or death, and to develop multivariate CHD risk scoring systems for men and women. The scores are based on age, blood pressure, anti-hypertensive medication, total and HDL cholesterol, smoking, diabetes, left ventricular hypertrophy and previous history of CHD. The generalisability and applicability of these risk estimation systems to Australian populations in the late 1990s is discussed.  相似文献   
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An equilibrium between free C1s and C1s bound in macromolecular C1 exists in human serum. This equilibrium can be utilized to incorporate radioiodinated C1s into serum C1. Human sera were incubated for 40 hr at 4 degrees C with 125I-C1s to allow the exchange between free and bound C1s to reach equilibrium. The C1 complex labeled in this manner was separated from the majority of serum proteins by centrifugation in linear 10 to 30% sucrose density gradients. The resulting fractions containing 125I-C1 can be used directly and conveniently in C1 activation assays that detect the cleavage of proenzyme C1s. Electrophoretic analysis on polyacrylamide gels showed the presence of only proenzyme 125I-C1s in serum C1, whether or not the applied labeled material contained 125I-C1s or other labeled proteins. The inability of C1 to incorporate C1s was shown to be the result of decreased stability of C1 upon activation.  相似文献   
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