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In this study a representative sample of German acute care hospitals is used to describe the effects of dementia within acute care hospitals. Data from hospital patients above age 60 with the diagnosis dementia (ICD 290, 293, 294 and 310), collected over an observation period of 12 years, are compared with nondemented hospital patients at the same ages. The differences in the average length of stay between demented and nondemented patients are only relatively small in German acute care hospitals. The degree of multimorbidity is higher and hospital infections are more frequent for demented patients. The main differences occur with mortality: demented inpatients of both sexes experience a hospital mortality which is about twice as high as for nondemented patients at the same ages.  相似文献   
124.
Cytomegalovirus (CMV) is the leading cause of congenital viral infection in the United States. To prevent damaging congenital CMV infections, it is necessary to have accurate population estimates of prevalence and to identify maternal factors associated with an elevated risk of congenital infection in the newborn. From 1980 through 1990, 17,163 offspring of predominantly low-income nonwhite women who delivered at a public hospital and 9892 newborns of predominantly mid- to upper-income white women who delivered at a private hospital were screened for congenital CMV infection. Women < 20 years old (adjusted prevalence odds ratio [POR], 4.8; 95% confidence interval [CI], 2.6-8.9) at the public hospital and all nonwhite women (adjusted POR, 1.6; 95% CI, 1.1-2.2) had an increased risk of delivering an infected newborn. Newborns of adolescent women in both populations had the highest prevalence of clinically apparent infection. Offspring of nonwhite low-income adolescents are at greatest risk for congenital CMV infection and more damaging sequelae.  相似文献   
125.
An interinstitutional study on the failed back surgery syndrome (FBSS) has determined that failure to recognize or adequately treat lateral stenosis of the lumbar spine with resultant nerve irritation and/or compression comprised the primary etiology in 57% to 58% of patients. Other common causes were recurrent or persistent disk herniation and lumbosacral adhesive arachnoiditis. The diagnosis of stenosis was made either by high-resolution CT scan of the lumbar spine or by directly testing lateral canal and for animal patency at the time of surgery. It is now appreciated that the process of degenerative disk disease, particularly when enhanced by diskectomy, results in progressive loss of intervertebral disk volume and predisposes to future ipsilateral or contralateral lateral spinal stenosis. Degenerative disk disease is ultimately a bilateral process and therefore surgical exposure should be bilateral. The direct and indirect costs of FBSS to patients and to society as well as the toll in human suffering are very high. This is particularly a matter of concern when it is realized that for many FBSS patients, surgery could have been avoided in the first place by preventive care or by innovative conservative treatment. When surgery is indicated, adequate diagnostic tests and the execution of appropriate procedures based upon this information should largely prevent the failed back surgery syndrome.  相似文献   
126.
The effect of an enriched inspired oxygen concentration on perceived exertion (RPE) was investigated while running at two submaximal treadmill loads. Twelve males (VO2 max = 49.3 ml/kg-min) worked at 50% and 80% VO2 max, breathing either air or 80% O2-20% N2 in random order using a single blind technique. Subjects were evaluated while running for 10 min and during a 20 min recovery. Heart rate (HR), ventilation (VE), respiration rate (RR), tidal volume (VT) and RPE were measured before, during and after work. Blood lactate was measured 1 min after work. Oxygen concentration did not statistically affect HR, VE, RR or VT during exercise or recovery. At both loads, RPE at the end of exercise was significantly reduced breathing the hyperoxic mixture. At 50% VO2 max, mean RPE decreased from 11.2 breathing room air to 9.6 breathing 80% O2 and, 80% VO2 max, from 13.8 to 11.7 (P less than 0.01). Blood lactates were significantly reduced breathing 80% O2; from 23.4 mg to 13.3 at 50% VO2 max and from 55.5 to 36.5 at 80% VO2 max (P less than 0.01). The RPE correlated with lactate (r=0.64) at the end of work. Results indicate that during moderate and heavy work RPE is significantly affected by the inspired O2 concentration and there is a significant relationship between RPE and blood lactate.  相似文献   
127.
The changes of nucleic acids content in the formation of conditioned skin-defence reflex was studied on inbred rats of various strains. In WGA rats the reflex was formed on the average aight stimulations. An increased RNA content was discovered by cytophotometric determination of the nucleic acids content in the neurons and perineural glia of the cerebral cortex in August rats only. It is assumed that an increased RNA synthesis in the animals of this strain can serve as the basis for their better training.  相似文献   
128.
Recent studies suggest that increased lipid peroxidation and lipid peroxidation products, such as 4-hydroxynonenal (HNE), contribute to neuronal loss in conditions associated with oxidative stress. The focus of the present study was to determine possible neuroprotective effects of elevated cyclic nucleotide levels against lipid peroxidation and HNE-mediated neural toxicity. Application of 8-bromo derivative analogs of cAMP or cGMP resulted in attenuation of HNE-induced increases in mitochondrial calcium, reactive oxygen species, and neuron loss. Similar results were obtained when neural cells were pretreated with the phosphodiesterase inhibitors zaprinast or isobutylmethylxanthanine (IBMX). These data are consistent with a possible neuroprotective role for elevated cyclic nucleotide levels in disorders associated with increases in lipid peroxidation and HNE.  相似文献   
129.
The broad aim of this interpretive study was to investigate the lived experiences of inter-organisational information system (IOIS) project members who worked in a 3-year-long IOIS project. The study presents an original longitudinal study of project member experiences. In this paper, we have described and analysed one core category, project power, which was derived from a grounded theory (GT) study. This study extends existing theories about power in organisational contexts, in particular the everyday use of power in projects. The paper shows how GT can be used to gain significant insights into a case study, and also generate new concepts. This paper gives detailed insights into the power issues as they played out in a complex IOIS project. This IOIS project spanned four user organisations, two suppliers, one national organisation, a research organisation and a government Ministry. One key finding is that, given the complexity of the project management structures in an IOIS project such as this, project members often resorted to formal authority as a means of getting things done, in the absence of informal links between organisations. The project history also had major ramifications on the use of power in this project.  相似文献   
130.
卟啉类L—B膜分子间相互作用的光谱研究   总被引:1,自引:0,他引:1  
以无取代的meso-四-(4-N)-吡啶基卟啉及其过渡族金属(主要Cu~(2+)、Zn~(2+))络合物制备L-B膜,以近紫外-可见吸收光谱和荧光光谱为手段,研究叶啉类分子在氯仿溶液中,L-B膜状态下以及固态状态下的相互作用。探讨分子聚集体的存在对光谱性质的影响。 为了研究叶咻类分子间的相互作用及其对光谱性质的影响,我们首先分析了叶啉在CHCl_3溶液中及固态状态下的近紫外-可见吸收光谱和荧光光谱。并将其与叶啉类分子的L-B膜作比较。结果表明,卟啉类的Soret吸收带带宽及峰位置在三种状态下均不相同,L-B膜的情况介于溶液中的和固体下的情况之间,说明了在L-B膜中,卟啉分子存在着某种形式的聚集体,且在这种聚集体中分子间的相互作用程度比固体弱,可以认为L-B膜上的分子呈准晶体状态。  相似文献   
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