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171.
Since late 1989, the cycle helmet wearing rate in New Zealand has risen from around 20% for adults and teenagers, and 40% for younger children, to more than 90% in all age groups. Cycle helmet wearing became mandatory under New Zealand law in January 1994. This paper considers the effect of cycle helmet wearing on hospitalised head injuries between 1990 and 1996, using cyclist limb injuries as a measure of exposure to the risk of cycling trauma. Non-motor vehicle crashes were treated separately from those involving a motor vehicle. Non-motor vehicle crashes were further subdivided by age group. Cyclist head injuries decreased with increasing helmet wearing rates for non-motor vehicle crashes in all age groups, and for motor vehicle crashes. For an increase of 5 percentage points in the helmet wearing rate, the corresponding decreases in head injuries in non-motor vehicle accidents were estimated to be 10.2, 5.3 and 3.2% for children of primary school age (5–12 years), secondary school age (13–18 years), and adults respectively. The corresponding decrease in hospitalisations for motor vehicle crashes was 3.6%. All results were significant at the 95% level. The relatively large increase in helmet wearing associated with the passing of a compulsory helmet wearing law in 1994 reduced head injuries by between 24 and 32% in non-motor vehicle crashes, and by 20% in motor vehicle crashes. No increase or decrease in the severity of head injuries for which cyclists were hospitalised over this period could be detected. This may have been due to the small and highly variable number of ‘high severity’ injuries.  相似文献   
172.
纺织品在生产、储存、运输及服用过程中会受到各种损伤,诸如机械损伤、热损伤、化学损伤、生物损伤等,一般的损伤可以用肉眼观察、触摸等方式进行鉴别和分析,但损伤往往是复杂的,在使用常规测试方法的基础上,必须借助现代仪器分析方法才能进行更为精确的分析.其中显微镜法能为其他分析方法提供相关技术支持;薄层色谱法适合染料、荧光增白剂、可溶性纤维助剂、纤维整理剂的鉴别;红外光谱法用于分析不溶性或大分子物质,而通过热分析可清楚的获知纺织品在受热过程中发生的变化.  相似文献   
173.
Objective: To investigate the relations among wives' labeling of their husbands' psychiatric disorder or brain injury as an organic illness, the husbands' perceived control over their disabilities, and the husbands' mental health. Participants: 57 male clients of the Department of Rehabilitation, Israel's Ministry of Defence (26 with a psychiatric disorder and 31 with a traumatic brain injury) and their wives. Measures: Illness Labeling Questionnaire, the Perceived Control Over Illness Questionnaire, and the Mental Health Inventory. Results: Husbands' mental health was low but did not differ according to disability; wives' labeling of husbands' condition was negatively related to the husbands' mental health; husbands' perceived control was positively related to their mental health for both disabilities. Conclusion: Organic illness labels, even when adopted by the wives of the persons with the disability, seem to be negatively related to that person's mental health, whereas perceived control over a mental disorder or a brain injury seems to contribute positively to mental health, independently of how the disorder or injury is labeled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
174.
Objective: To understand how traumatic brain injury (TBI) affects parent-child interactions acutely following injury. Participants: Young children hospitalized for TBI (n = 80) and orthopedic injuries (OI; n = 113). Method: Raters coded videotaped interactions during free play and structured tasks for parental warmth/responsiveness and negativity and child warmth, behavior regulation, and cooperation. Raters also counted parental directives, critical/restricting statements, and scaffolds. Results: Parents of children with TBI exhibited less warm responsiveness and made more directive statements during a structured task than parents in the OI group. Children with TBI displayed less behavior regulation than children with OI. Parental warm responsiveness was more strongly related to child cooperativeness in the OI group than in the TBI group. Child behavior also mediated group differences in parental responsiveness and directiveness. TBI accounted for as much variance in parental behaviors as or more than did sociodemographic factors. Conclusion: TBI-related changes in child behavior may negatively influence parent-child interactions and disrupt the reciprocity between parent and child. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
175.
非均匀载荷下双层套管的传递系数   总被引:2,自引:0,他引:2  
杨斌  张效羽 《石油钻采工艺》2001,23(4):13-15,83
传递系数是衡量双层组合套管效果的主要指标。由于应力应变关系的复杂性,用理论方法求解非均匀载荷作用下该种套管的传递系数十分困难。文中用有限元方法计算了不同类型非均匀载荷作用下的传递系数,对其变化规律进行了分析。在大量计算结果的基础上,进行了传递系数计算公式的回归分析,给出了椭圆分布载荷作用下传递系数的拟合曲线及回归公式。这些结果弥补了理论分析的不足,为双层组合套管的设计提供了有效的计算依据。计算过程还证实了双层组合套管的一些试验结果,对该种套管的特点有了进一步的认识。在计算均匀载荷作用下传递系数时,文中方法与理论方法的相对误差小于0.6%;在进行曲线拟合时,最大相对误差小于2%。  相似文献   
176.
This cross-sectional study evaluated cow comfort measures in free stall dairies across the United States as part of the National Animal Health Monitoring System's Dairy 2007 study. The study was conducted in 17 states and evaluations were completed between March 5 and September 5, 2007. Assessors recorded hygiene and hock scores, number of cows housed in the pen, the number of cows standing with only the front feet in a stall, standing fully in a stall, and lying in a stall. Facility design measures included bedding type, bedding quantity, stall length and width, presence of a neck rail or brisket locator, and relevant distances from the rear and bed of the stall. Of the 491 operations that completed the cow comfort assessment, 297 had Holstein cows housed in free stalls and were included in this analysis. Negative binomial models were constructed to evaluate the following outcomes: the number of cows that were very dirty, had severe hock injuries, stood with front feet in the stall, stood with all feet in the stall, and were lying in the stall. Hygiene was better on farms that did not tail dock cows compared with those that did (5.7 vs. 8.8% were dirty) and on farms located in the study's west region compared with those located in the east region (5.2 vs. 9.7% were dirty). Severe hock injuries were less common on farms in the west than those in the east (0.5 vs. 4.1%). In addition, severe hock injuries were less common on farms that used dirt as a stall base or sand as bedding compared with farms that did not. A higher percentage of cows was standing with front feet in the stall at higher ambient temperatures (incidence rate ratio = 1.016) and as time since feeding increased (incidence rate ratio = 1.030). A lower percentage of cows were standing with front feet in the stall when the stalls were shorter and when there were fewer cows per stall. Standing fully in a stall was performed by a higher percentage of cows during the summer than during the spring (13.6 vs. 8.1%), when cows were provided free stalls with rubber mats or mattresses, and as the distance from the rear curb to neck rail increased. A higher percentage of cows were lying in a stall when sand bedding was used, when bedding was added more frequently, and during the spring months. Results of this national survey indicate that tail docking provides no benefit to cow hygiene and that stall base and bedding are key factors influencing hock injuries and stall usage on US free stall dairy farms.  相似文献   
177.
Objective: Social psychological theories such as attribution theory have been applied to conditions such as depression and physical disability, but not to traumatic brain injury (TBI). The goal of this paper is to show that that attribution theory and related concepts help to explain the public's misconceptions about TBI and other challenges faced by clinicians and families of persons with TBI. Results: Research shows that misconceptions about brain injury occur because people misattribute the actions of persons with brain injury. These misattributions reflect two features: (a) the absence of visible markers of the injury, and (b) the tendency to compare persons with TBI with their peers rather than their own preinjury performance. These two processes lead to the opposite pattern to the stigma that occurs with visible disabilities: specifically, a failure among members of the public to recognize that problematic behaviors may result from the injury. This analysis suggests several therapeutic strategies for managing public misconceptions in ways that enhance coping and recovery. Conclusion: Clarifying the attribution processes that underpin misconceptions about brain injury provides a framework for enhancing rehabilitation and addressing these misconceptions effectively. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
178.
Peripheral capsaicin treatment induces molecular changes that sensitize the responses of nociceptive neurons in the spinal dorsal horn. The current studies demonstrate that capsaicin also undermines the adaptive plasticity of the spinal cord, rendering the system incapable of learning a simple instrumental task. In these studies, male rats are transected at the second thoracic vertebra and are tested 24 to 48 hours later. During testing, subjects receive shock to one hindleg when it is extended (controllable stimulation). Rats quickly learn to maintain the leg in a flexed position. Rats that have been injected with capsaicin (1% or 3%) in the hindpaw fail to learn, even when tested on the leg contralateral to the injection. This learning deficit lasts at least 24 hours. Interestingly, training with controllable electrical stimulation prior to capsaicin administration protects the spinal cord against the maladaptive effects. Rats pretrained with controllable stimulation do not display a learning deficit or tactile allodynia. Moreover, controllable stimulation, combined with naltrexone, reverses the capsaicin-induced deficit. These data suggest that peripheral inflammation, accompanying spinal cord injuries, might have an adverse effect on recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
179.
Experiments in completely spinal cord transected (Tx) cats have provided compelling evidence that clonidine combined with tail stimulation can promote locomotor function recovery. However, clonidine has generally failed to induce locomotor activity in other comparable animal models suggesting the existence of species- or condition-specific effects. This study aimed at investigating the effects of clonidine administered (0.25 or 5.0 mg/kg, i.p.) in mice during tail pinching in early (6-7 days post-Tx) or late (41-42 days post-Tx) paraplegic animals (Th9/10 level). Comparisons were made with the effects induced by 8-OH-DPAT (1.0 mg/kg, i.p.), a 5-HT1A/7 receptor agonist known to display prolocomotor effects. Clonidine with or without tail pinching failed to induce hind limb movements and even suppressed the frequency of spontaneously occurring nonlocomotor (NLM) and locomotor-like movements (LM) whereas tail pinching alone (prior to clonidine administration) increased the frequency of spontaneous movements specifically in late chronic animals. In turn, 8-OH-DPAT clearly induced hind limb movements that remained relatively unchanged during tail pinching. Altogether, the results suggest that the prolocomotor effects of clonidine reported elsewhere must depend upon stimuli or factors that remain to be identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
180.
Preclinical studies have shown that postconditioning with hydrogen sulfide (H2S) exerts cardioprotective effects against myocardial ischemia-reperfusion injury (IRI). The aim of this study was to appraise the current evidence of the cardioprotective effects of H2S against IRI in order to explore the future implementation of H2S in clinical cardiac transplantation. The current literature on H2S postconditioning in the setting of global myocardial ischemia was systematically reviewed and analyzed, performing meta-analyses. A literature search of the electronic databases Medline, Embase and Cinahl identified 1835 studies that were subjected to our pre-defined inclusion criteria. Sixteen studies were considered eligible for inclusion. Postconditioning with H2S showed significant robust effects with regard to limiting infarct size (standardized mean difference (SMD) = −4.12, 95% CI [−5.53–−2.71], p < 0.00001). Furthermore, H2S postconditioning consistently resulted in a significantly lower release of cardiac injury markers, lower levels of oxidative stress and improved cardiac function. Postconditioning with slow-releasing H2S donors offers a valuable opportunity for novel therapies within cardiac preservation for transplantation. Before clinical implication, studies evaluating the long-term effects of H2S treatment and effects of H2S treatment in large animal studies are warranted.  相似文献   
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