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31.
Visual correlation of network alerts   总被引:1,自引:0,他引:1  
The VisAlert visual correlation tool facilitates situational awareness in complex network environments by providing a holistic view of network security to help detect malicious activities. Information visualization techniques and methods in many applications have effectively increased operators' situational awareness, letting them more effectively detect, diagnose, and treat anomalous conditions. Visualization elevates information comprehension by fostering rapid correlation and perceived associations. Our visualization technique integrates the information in log and alert files into an intuitive, flexible, extensible, and scalable visualization tool - VisAlert - that presents critical information concerning network activity in an integrated manner, increasing the user's situational awareness.  相似文献   
32.
In this paper, we discuss the problem of implementing impedance control in the presence of model uncertainties and its application to robot force control. We first propose a sliding mode-based impedance controller. The implementation of the targeted impedance, and the preservation of stability in the presence of model uncertainties, are the key issues in the proposed approach. Using sliding mode control, a simple and robust algorithm is obtained so that the targeted impedance can be accurately implemented without the exact model of the robot. The controller is designed in terms of the task space coordinates. The chattering in the sliding mode control is eliminated by using a continuous function. The problem of force control is also addressed for the impedance controlled robot. An off-line estimation method of the environment model is suggested and used in the force control scheme. The proposed impedance and force control schemes have been experimentally verified on a two degree-of-freedom direct-drive robot arm. The experimental results are presented in this paper.  相似文献   
33.
The purpose of this study was to evaluate the diagnostic efficacy of the double inversion recovery fast spin echo (DIR-FSE) sequence for brain imaging compared to the fluid-attenuated inversion recovery (FLAIR) sequence. DIR-FSE and FLAIR-FSE sequences were obtained and compared side by side. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, image quality, and artifacts. In addition, contrast ratios and contrast-to-noise ratios were determined. Scan time of DIR-FSE was 33% longer than scan time of FLAIR-FSE. Overall lesion conspicuity was equal on DIR-FSE and FLAIR-FSE; however, DIR-FSE showed particular advantages for infratentorial lesions and lesions with only poor contrast on T2-weighted images, whereas FLAIR was slightly superior for small superficial cerebral abnormalities. Gray-white differentiation was better with DIR-FSE. Cerebrospinal fluid suppression was equal on both sequences; cerebrospinal fluid pulsation artifacts were more pronounced on DIR-FSE but did not cause diagnostic difficulties on these images. We conclude that DIR-FSE might be obtained if infratentorial lesions and abnormalities with only slightly prolonged T2 relaxation times are suspected. Otherwise, FLAIR-FSE seems preferable.  相似文献   
34.
OBJECTIVE: To study the effect of fluoxetine (FL) and amitriptyline (AM), alone and in combination, in patients with fibromyalgia (FM). METHODS: Nineteen patients with FM completed a randomized, double-blind crossover study, which consisted of 4 6-week trials of FL (20 mg), AM (25 mg), a combination of FL and AM, or placebo. Patients were evaluated on the first and last day of each trial period. Outcome measures included a tender point score, the Fibromyalgia Impact Questionnaire (FIQ), the Beck Depression Inventory (BDI) scale, and visual analog scales (VAS) for global well-being (1 completed by the physician and 1 by the patient), pain, sleep trouble, fatigue, and feeling refreshed upon awakening. RESULTS: Both FL and AM were associated with significantly improved scores on the FIQ and on the VAS for pain, global well-being, and sleep disturbances. When combined, the 2 treatments worked better than either medication alone. Similar, but nonsignificant, improvement occurred in the BDI scale, the physician global VAS, and the VAS for fatigue and feeling refreshed upon awakening. Trends were less clear for the tender point score. CONCLUSION: Both FL and AM are effective treatments for FM, and they work better in combination than either medication alone.  相似文献   
35.
A robot was used to make fiber-optic reflectance measurements from 400 to 700 nm in 10-nm increments at six sites, 10 cm apart, along the length of 48 pork loins. Meat quality was assessed in the longissimus dorsi near the thoracolumbar junction using 1) a bag-drip method for fluid loss, 2) a subjective evaluation of wetness, 3) a colorimeter measurement of paleness (CIE L), and 4) a subjective evaluation for Japanese pork color scores (JPCS). Sorting of the loins in the commercial plant from which they originated was correlated (P < .01) with fluid loss (r=.57), with wetness scores (r=-.57), with CIE L* (r=.71), and with JPCS (r=-.64). Laboratory measurements of pH at the site of meat quality assessment were correlated (P < .01) with fluid loss (r=-.61), with wetness scores (r=.65), with CIE L* (r=-.74), and with JPCS (r=.77). Average spectra obtained robotically were correlated (P < .01) with fluid loss (r=.56 at 670 nm, and R=.76 adding 560 and 540 nm), with wetness score (r=-.65 at 480 nm, and R=.75 adding 530 and 570 nm), with CIE L* (r=.76 at 480 nm, and R=.82 adding 690 and 520 nm), and with JPCS (r=-.70). In sorting loins that were all categorized as normal at the plant, mean reflectance data collected robotically were correlated with fluid loss, r=.42 (P > .05) at 700 nm and R=.58 (P > .05) adding 430 nm; with wetness score, r=.25 (P > .05); with CIE L*, r=.58 (P < .025) at 700 nm; and with JPCS, r=-.71 (P < .01) at 700 nm. Thus, as well as detecting obvious PSE loins, the robotic probe also had a limited capability to sort loins all categorized as normal at the plant.  相似文献   
36.
Because of potential mutagenic effects of radiation on the soon-to-be fertilized ovum, we questioned whether we should advise against conception during the cycle in which a hysterosalpingogram is performed. Our results do not suggest any increase in the incidence of spontaneous abortion or congenital anomalies in these patients. Therefore, we see no need to advise against conception during the cycle in which a hysterosalpingogram is performed.  相似文献   
37.
An approach to real-time control is presented that involves the adaption of existing (commercial) hardware and the integration of new hardware and software, such that both feedback control and offline programming using either task or joint-space coordinates are possible. The approach is illustrated in detail through the implementation of a controller that replaces the conventional Victor's assembly language (VAL) II-based controller with the PUMA 560 robot. The controller presents an improvement over the system under VAL in a number of ways, in addition to being able to use either task or joint-space information in the most general form. In particular, the hardware and software of the new controller can accommodate novel sensory systems, robot programming languages, and dynamic models for research and evaluation of advanced control methods  相似文献   
38.
BACKGROUND: Anemia affects almost two-thirds of pregnant women in developing countries and contributes to maternal morbidity and mortality and to low birthweight. OBJECTIVE: To determine the prevalence of anemia and the dietary and socioeconomic factors associated with anemia in pregnant women living in an urban community setting in Hyderabad, Pakistan. METHODS: This was a prospective, observational study of 1,369 pregnant women enrolled at 20 to 26 weeks of gestation and followed to 6 weeks postpartum. A blood sample was obtained at enrollment to determine hemoglobin levels. Information on nutritional knowledge, attitudes, and practice and dietary history regarding usual food intake before and during pregnancy were obtained by trained interviewers within 1 week of enrollment. RESULTS: The prevalence of anemia (defined by the World Health Organization as hemoglobin < 11.0 g/dL) in these subjects was 90.5%; of these, 75.0% had mild anemia (hemoglobin from 9.0 to 10.9 g/dL) and 14.8% had moderate anemia (hemoglobin from 7.0 to 8.9 g/dL). Only 0.7% were severely anemic (hemoglobin < 7.0 g/ dL). Nonanemic women were significantly taller, weighed more, and had a higher body mass index. Multivariate analysis after adjustment for education, pregnancy history, iron supplementation, and height showed that drinking more than three cups of tea per day before pregnancy (adjusted prevalence odds ratio [aPOR], 3.2; 95% confidence interval [CI], 1.3 to 8.0), consumption of clay or dirt during pregnancy (aPOR, 3.7; 95% CI, 1.1 to 12.3), and never consuming eggs or consuming eggs less than twice a week during pregnancy (aPOR, 1.7; 95% CI, 1.1 to 2.5) were significantly associated with anemia. Consumption of red meat less than twice a week prior to pregnancy was marginally associated with anemia (aPOR, 1.2; 95% CI, 0.8 to 1.8) but was significantly associated with lower mean hemoglobin concentrations (9.9 vs. 10.0 g/dL, p = .05) during the study period. A subanalysis excluding women with mild anemia found similar associations to those of the main model, albeit even stronger. CONCLUSIONS: A high percentage of women at 20 to 26 weeks of pregnancy had mild to moderate anemia. Pica, tea consumption, and low intake of eggs and red meat were associated with anemia. Women of childbearing age should be provided nutritional education regarding food sources of iron, especially prior to becoming pregnant, and taught how food choices can either enhance or interfere with iron absorption.  相似文献   
39.
Introduction: Hemophilia A (HA) is an X-linked bleeding disorder caused by factor VIII (FVIII) deficiency or dysfunction due to F8 gene mutations. HA carriers are usually asymptomatic because their FVIII levels correspond to approximately half of the concentration found in healthy individuals. However, in rare cases, a carrier may exhibit symptoms of moderate to severe HA primarily due to skewed inactivation of her non-hemophilic X chromosome. Aim: The aim of the study was to investigate X-chromosome inactivation (XCI) patterns in HA carriers, with special emphasis on three karyotypically normal HA carriers presenting with moderate to severe HA phenotype due to skewed XCI, in an attempt to elucidate the molecular mechanism underlying skewed XCI in these symptomatic HA carriers. The study was based on the hypothesis that the presence of a pathogenic mutation on the non-hemophilic X chromosome is the cause of extreme inactivation of that X chromosome. Methods: XCI patterns were studied by PCR analysis of the CAG repeat region in the HUMARA gene. HA carriers that demonstrated skewed XCI were further studied by whole-exome sequencing (WES) followed by X chromosome-targeted bioinformatic analysis. Results: All three HA carriers presenting with the moderate to severe HA phenotype due to skewed XCI were found to carry pathogenic mutations on their non-hemophilic X chromosomes. Patient 1 was diagnosed with a frameshift mutation in the PGK1 gene that was associated with familial XCI skewing in three generations. Patient 2 was diagnosed with a missense mutation in the SYTL4 gene that was associated with familial XCI skewing in two generations. Patient 3 was diagnosed with a nonsense mutation in the NKAP gene that was associated with familial XCI skewing in two generations. Conclusion: Our results indicate that the main reason for skewed XCI in our female HA patients was negative selection against cells with a disadvantage caused by an additional deleterious mutation on the silenced X chromosome, thus complicating the phenotype of a monogenic X-linked disease. Based on our study, we are currently offering the X inactivation test to symptomatic hemophilia carriers and plan to expand this approach to symptomatic carriers of other X-linked diseases, which can be further used in pregnancy planning.  相似文献   
40.
The present research investigated the role of the physical body as a source of self-esteem and tested the hypothesis derived from terror management theory that reminding people of their mortality increases self-esteem striving in the form of identification with one's body, interest in sex, and appearance monitoring. The results revealed that individuals high in body esteem responded to mortality salience manipulations with increased identification with their physical bodies in Study 1 and with increased interest in sex in Study 2. Study 3 showed that reminders of death led to decreased appearance monitoring among appearance-oriented participants who were low in body esteem. These findings provide insight into why people often go to extreme lengths to meet cultural standards for the body and its appearance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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