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141.
Elevated activities of serum aminotransferases are a common sign of liver disease and are observed more frequently among diabetics than in the general population. Whether this association is due to confounding factors is unknown. The authors investigated whether diabetes was significantly associated with elevated serum activity of alanine aminotransferase (ALT) after adjustment for factors common to both diabetes and raised ALT. Data from 2,999 men and women aged 20-74 years representative of the Mexican American population of the southwestern United States were obtained from the Hispanic Health and Nutrition Examination Survey (1982-1984). Approximately 6% of men and 2% of women had elevated serum ALT activity (>43 IU/liter). The odds ratio for diabetes as a predictor of elevated ALT was 4.1 (95% confidence interval 2.3-7.6) adjusted for age and sex, which decreased to 3.0 (95% confidence interval 0.92-9.74) after adjustment for age, sex, body mass index, alcohol consumption, and other factors. In addition to diabetes, body mass index was also significantly (p < 0.05) associated with elevated ALT activity. Heavier alcohol consumption and male sex increased the likelihood of elevated ALT, whereas coffee consumption reduced it. Diabetes and liver injury appear to be associated, even with control for factors in common.  相似文献   
142.
Conducted 5 experiments on the stimulus characteristics mediating 1 rat's attraction for another. 120 Sprague-Dawley and 12 Wistar male albino rats were tested for attraction (physical approach) to (a) a variety of stimulus objects (familiar and unfamiliar objects; stuffed, anesthetized, tethered, and free-moving stimulus rats), (b) rats varying in static stimulus qualities (normal, dyed, shaven, or perfumed), and (c) rats under varying degrees of sensory impairment (normal, blinded, shaven, whiskerless, or anosmic). Variations in sensory capacity or static stimulus characteristics had little effect on social attraction; variations in the dynamic quality of the other rat had large effects. Ss were more attracted to rats which could move and respond to them than to stuffed or anesthetized rats. Results suggest that the quality of behavior and the possibility of interaction between animals mediates gregariousness in rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
143.
The effect of isometric exercise on serum creatinine phosphokinase (CPK) activity in 14 psychotic patients in remission and ten normal controls was studied. The increases in serum CPK activity at 18 and 42 hours after exercise were no significantly different in patients and controls. The postexercise serum CPK activities in the patients were significantly less than the peak serum CPK levels when they were psychotic. There were no significant correlations between postexercise serum CPK activity and preexercise or peak serum CPK activity in the patient group. It is unlikely that increased isometric muscle tension is a major causative factor in the increased serum CPK levels frequently found in psychotic patients.  相似文献   
144.
Rectangular pulse-modulated microwave radiation has been shown to produce auditory responses in mammals. It is therefore reasonable to explore the possibility of using microwave pulses to achieve an estimate of sensori-neural involvement in the objective evaluation of human hearing and to assess the presence of tumors or brainstem lesions in patients with neurological disorders. In this paper we shall show that microwave-evoked auditory response of cats closely resembles that evoked by acoustic pulse. We shall also give preliminary results obtained from electrodes fastened to the vertex of the skull after successive coagulative production of lesions in the inferior colliculus, lateral lemniscus, and superior olivary nucleus.  相似文献   
145.
Although sleep disturbances in children are common, little is known about the relationship between children's sleep disruptions and maternal sleep and daytime functioning. Forty-seven mothers completed measures of sleep, depression, parenting stress, fatigue, and sleepiness. Significant differences in maternal mood and parenting stress were found between mothers of children with and without significant sleep disturbances. Regression analyses showed that the quality of the children's sleep significantly predicted the quality of maternal sleep. In addition, maternal sleep quality was a significant predictor of maternal mood, stress, and fatigue. Results from this pilot study support the need for future research examining the relationship between child sleep disturbances and maternal daytime functioning, and they highlight the importance of screening for and treating pediatric sleep disruptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
146.
Precise and controlled manipulation of individual gold nanoparticles (deposited on a Si/SiO2 surface) in liquid environments using the tip of a scanning force microscope is reported for the first time. Experiments were performed in deionized water and in ethanol as a prototype for an organic solvent. Analysis of the amplitude signal of the cantilever before and during manipulation reveals that the particles are pushed across the surface, similar to the manipulation of nanoparticles in air.  相似文献   
147.
Several proteases like the high temperature requirement A (HtrA) protein family containing internal or C-terminal PDZ domains play key roles in protein quality control in the cell envelope of Gram-negative bacteria. While several HtrA proteases have been extensively characterized, many features of C-terminal processing proteases such as tail-specific protease (Tsp) are still unknown. To fully understand these cellular control systems, individual domains need to be targeted by specific peptides acting as activators or inhibitors. Here, we describe the identification and design of potent inhibitors and activators of Tsp. Suitable synthetic substrates of Tsp were identified and served as a basis for the generation of boronic acid-based peptide inhibitors. In addition, a proteomic screen of E. coli cell envelope proteins using a synthetic peptide library was performed to identify peptides capable of amplifying Tsp's proteolytic activity. The implications of these findings for the regulation of PDZ proteases and for future mechanistic studies are discussed.  相似文献   
148.
Allostery is a basic principle of control of enzymatic activities based on the interaction of a protein or small molecule at a site distinct from an enzyme's active center. Allosteric modulators represent an alternative approach to the design and synthesis of small‐molecule activators or inhibitors of proteases and are therefore of wide interest for medicinal chemistry. The structural bases of some proteinaceous and small‐molecule allosteric protease regulators have already been elucidated, indicating a general mechanism that might be exploitable for future rational design of small‐molecule effectors.  相似文献   
149.
In this study, the stability of arsenic compounds in fresh and frozen samples of raw, boiled and fried Atlantic cod (Gadhus morhua), Atlantic salmon (Salmo salar) and blue mussel (Mytilus edulis) were examined. Results show that the total arsenic concentrations of the fresh Atlantic cod and Atlantic salmon samples were not different from the frozen samples within the same seafood type. For blue mussel, the total arsenic concentration decreased significantly after storage. Inorganic arsenic was found only in blue mussels and, importantly, no significant increase of inorganic arsenic was observed after processing or after storage by freezing. The content of tetramethylarsonium ion was generally low in all samples types, but increased significantly in all fried samples of both fresh and frozen seafood. Upon storage by freezing, the arsenobetaine content was reduced significantly, but only in the samples of blue mussels.  相似文献   
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