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11.
BACKGROUND: A significant proportion of burn patients with inhalation injuries incur difficulties with airway protection, dysphagia, and aspiration. In assessing the need for intubation in burn patients, the efficacy of fiberoptic laryngoscopy was compared with clinical findings and the findings of diagnostic tests, such as arterial blood gas analysis, measurement of carboxyhemoglobin levels, pulmonary function tests, and radiography of the lateral aspect of the neck. OBJECTIVE: To determine if these patients were at risk for aspiration or dysphagia, barium-enhanced fluoroscopic swallowing studies were performed. DESIGN: Prospective study. SETTINGS: Burn intensive care unit in an academic tertiary referral center. MAIN OUTCOME MEASURES: Need for endotracheal intubation and potential for aspiration. RESULTS: Six (55%) of 11 patients had clinical findings and symptoms that indicated, under traditional criteria, endotracheal intubation for airway protection. Visualization of the upper airway with fiberoptic laryngoscopy obviated the need for endotracheal intubation in all 11 patients. These patients also failed to evidence an increased risk of aspiration or other swallowing dysfunction. CONCLUSIONS: In comparison with other diagnostic criteria, fiberoptic laryngoscopy allows differentiation of those patients with inhalation injuries who, while at risk for upper airway obstruction, do not require intubation. These patients may be safely observed in a monitored setting with serial fiberoptic examinations, thus avoiding the possible complications associated with intubation of an airway with a compromised mucosalized surface. In these patients, swallowing abnormalities do not manifest.  相似文献   
12.
In this article, a model for estimating bioenergy production potentials in 2050, called the Quickscan model, is presented. In addition, a review of existing studies is carried out, using results from the Quickscan model as a starting point. The Quickscan model uses a bottom-up approach and its development is based on an evaluation of data and studies on relevant factors such as population growth, per capita food consumption and the efficiency of food production. Three types of biomass energy sources are included: dedicated bioenergy crops, agricultural and forestry residues and waste, and forest growth. The bioenergy potential in a region is limited by various factors, such as the demand for food, industrial roundwood, traditional woodfuel, and the need to maintain existing forests for the protection of biodiversity. Special attention is given to the technical potential to reduce the area of land needed for food production by increasing the efficiency of food production. Thus, only the surplus area of agricultural land is included as a source for bioenergy crop production. A reference scenario was composed to analyze the demand for food. Four levels of advancement of agricultural technology in the year 2050 were assumed that vary with respect to the efficiency of food production. Results indicated that the application of very efficient agricultural systems combined with the geographic optimization of land use patterns could reduce the area of land needed to cover the global food demand in 2050 by as much as 72% of the present area. A key factor was the area of land suitable for crop production, but that is presently used for permanent grazing. Another key factor is the efficiency of the production of animal products. The bioenergy potential on surplus agricultural land (i.e. land not needed for the production of food and feed) equaled 215–1272 EJ yr−1, depending on the level of advancement of agricultural technology. The bulk of this potential is found in South America and Caribbean (47–221 EJ yr−1), sub-Saharan Africa (31–317 EJ yr−1) and the C.I.S. and Baltic States (45–199 EJ yr−1). Also Oceania and North America had considerable potentials: 20–174 and 38–102 EJ yr−1, respectively. However, realization of these (technical) potentials requires significant increases in the efficiency of food production, whereby the most robust potential is found in the C.I.S. and Baltic States and East Europe. Existing scenario studies indicated that such increases in productivity may be unrealistically high, although these studies generally excluded the impact of large scale bioenergy crop production. The global potential of bioenergy production from agricultural and forestry residues and wastes was calculated to be 76–96 EJ yr−1 in the year 2050. The potential of bioenergy production from surplus forest growth (forest growth not required for the production of industrial roundwood and traditional woodfuel) was calculated to be 74 EJ yr−1 in the year 2050.  相似文献   
13.
We present the case of a patient affected with Williams syndrome (WS), who developed a suspected malignant hyperthermia (MH) reaction to general anesthesia. The proximity to the WS region of the gene encoding the L-type voltage-gated calcium channel alpha 2/delta-subunit (CACNL2A) on 7q11.23-q21.1, previously shown to be closely linked to some forms of MH susceptibility, prompted us to investigate whether this gene is deleted in WS. Linkage studies and fluorescence in situ hybridization analysis demonstrated that the CACNL2A locus is localized outside the WS deleted region.  相似文献   
14.
INTRODUCTION: Incessant monomorphic ventricular tachycardia (VT) with a right bundle branch block morphology and a northwest axis is a rare arrhythmic complication in a patient with hypertrophic cardiomyopathy and apical left ventricular aneurysm. METHODS AND RESULTS: The origin of this VT was localized using the following criteria: the presence of entrainment without fusion, equal intervals from the stimulus to the beginning of the QRS complex and from the electrogram to the QRS complex during VT, and the first postpacing interval identical to the tachycardia cycle length. Radiofrequency energy applied to the septoapical part of the apical left ventricular aneurysm terminated the tachycardia within 2 seconds. CONCLUSION: Using criteria to guide radiofrequency (RF) ablation of VT in patients with coronary artery disease, an incessant monomorphic VT in a patient with hypertrophic cardiomyopathy was successfully ablated.  相似文献   
15.
A recent study of the distribution of NADPH-diaphorase (NADPHd) and nitric oxide synthase (NOS) in a turtle brain (Brüning et at. [1994]: J. Comp. Neurol. 348:183-206) has revealed that these enzymes are not only widely distributed throughout the brain, but also seem to be colocalized with other classical neurotransmitters, such as catecholamines and acetylcholine. The main goals of the present study were 1) to determine sites of colocalization of NADPHd/NOS with tyrosine hydroxylase (TH, as marker for catecholamines), and 2) by studying a representative of another reptilian radiation, to assess primitive and derived traits of the distribution of NADPHd and NOS in the brains of reptiles. For that purpose, single (NADPHd or NOS) and double staining (NADPHd with TH, or NOS with TH) techniques were applied to the brains of adult gekkonid lizards (Gekko gecko). The distribution of NADPHd and NOS in Gekko was largely comparable to that in turtles, which implies involvement in certain functions of these enzymes. Notable differences, however, were observed in the thalamus and pretectum. Colocalization was observed in numerous cells of the ventral tegmental area, the substantia nigra, and the retrorubral dopaminergic cell group. In other catecholaminergic cell groups, e.g., the locus coeruleus and the solitary tract nucleus, TH-immunoreactive cells and NADPHd/NOS-positive cells were closely intermingled, but not double-stained. From the present evidence, it is concluded that extensive colocalization of NADPHd/NOS with catecholamines occurs in the midbrain dopaminergic cell groups of reptiles and birds, but not (or only sparsely) in the corresponding cell groups of amphibians and mammals.  相似文献   
16.
Feeding difficulty and malnutrition are common in disabled children. Intake may be reduced because of anorexia, chewing and swallowing difficulties, or vomiting. Feeding is often time consuming, unpleasant, and may result in aspiration. Malnutrition may result in impaired growth and neurodevelopment, and impaired cardiorespiratory, gastrointestinal, and immune functions. Multidisciplinary assessment is recommended and should include a feeding history, oral-motor examination, and nutritional assessment. The energy requirements of most disabled children are less than those for a normal child of the same age but may be increased by spasticity, athetosis, convulsions, and recurrent infections. Micronutrient deficiencies may occur even in children receiving nutritionally complete feeds if the volume is reduced because of low energy requirements. Oral intake may be improved by a change of posture, special seating, feeding equipment, oral desensitization, mashing or pureeing of lumpy food, thickening of liquids, use of calorie supplements, and treatment of reflux/esophagitis. Non-oral feeding should be considered when oral feeding is unsafe, not enjoyable, inadequate, or very time consuming. Long-term support requires a gastrostomy. This is less obtrusive than a nasogastric tube, less likely to become displaced, less traumatic, and is associated with improved quality of life, but is also associated with significant morbidity. If there is symptomatic reflux a fundoplication may be required, but this is associated with significant mortality and substantial morbidity.  相似文献   
17.
We studied the relationship between wall motion abnormalities determined by echocardiography and the signal-averaged electrocardiogram in 82 consecutive patients during the acute phase of a first myocardial infarction. An abnormal signal-averaged electrocardiogram was defined as the presence of two of the following criteria: a QRS duration > or = 114 ms, a root mean square voltage (RMS) of the last 40 ms < or = 25 microV and an amplitude signal lower than 40 microV lasting > or = 39 ms. The left ventricle was divided into 13 segments and the contraction pattern divided into akinesia alone (including dyskinesia) (group A), hypokinesia alone (group B) and both hypokinesia and akinesia (group C). An abnormal signal-averaged electrocardiogram was found in 14/82 patients (17%) and was correlated with the persistence of occlusion of the infarct-related vessel (32% vs 9%, P < 0.02). In patients with a patent vessel, the incidence of an abnormal signal-averaged electrocardiogram was 14% in group A, 9% in group B and 0% in group C (NS). In patients with an occluded vessel an abnormal signal-averaged electrocardiogram was found in 10% of group A patients, in 36% in group B patients and in 75% of group C patients (P = 0.05). Our study suggests that the presence of hypokinetic areas during the acute phase of a first myocardial infarction and an abnormal signal-averaged electrocardiogram indicate an occluded infarct-related vessel.  相似文献   
18.
Through allele-segregation and loss-of-heterozygosity analyses, we demonstrated loss of the translocation-derivative chromosome 3 in five independent renal cell tumors of the clear-cell type, obtained from three members of a family in which a constitutional t(2;3)(q35;q21) was encountered. In addition, analysis of the von Hippel-Lindau gene, VHL, revealed distinct insertion, deletion, and substitution mutations in four of the five tumors tested. On the basis of these results, we conclude that, in this familial case, an alternative route for renal cell carcinoma development is implied. In contrast to the first hit in the generally accepted two-hit tumor-suppressor model proposed by Knudson, the familial translocation in this case may act as a primary oncogenic event leading to (nondisjunctional) loss of the der(3) chromosome harboring the VHL tumor-suppressor gene. The risk of developing renal cell cancer may be correlated directly with the extent of somatic (kidney) mosaicism resulting from this loss.  相似文献   
19.
Fluorescence microscopy of caudal epididymal spermatozoa stained with 3, 3' dihexyloxacarbocyanine iodide (DiOC6(3)) showed intense fluorescence along the concave surface of the apical hook of spermatozoa of Rattus species and along the upper concave margin of the sperm head in Mus musculus. In the spermatozoa of Hydromys chrysogaster, Melomys cervinipes, and Pseudomys australis, the two ventral processes also fluoresced brightly. In P. australis, fluorescence in the apical hook of sperm heads was largely localized to its upper and lower surfaces. The sperm of N. alexis did not show consistent positive fluorescence. The localization of fluorescence in these spermatozoa after staining with DiOC6(3) was mainly restricted to regions where a large accumulation of perinuclear theca material lies beneath the plasmalemma. The reason for this remains to be determined, but DiOC6(3) may be useful for quickly demonstrating areas of abundant perinuclear thecal material in sperm heads of eutherian mammals by light microscopy.  相似文献   
20.
The frequently assumed “freshness” constraint on the source states in multiple authentication schemes is not necessary if one allows the encoding rule to change between subsequent transmissions. In the paper it is shown that the main existing lower bounds on the probabilities of successful attack on multiple authentication schemes also hold for this new setup. Furthermore, Stinson's (1988) bound for the substitution attack is strengthened  相似文献   
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