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31.
OBJECTIVE: To audit the outcome of temporary endocardial pacing in an elderly population. DESIGN: Retrospective case-series analysis. SETTING: The Department of Medicine for the Elderly at the Wrexham Maelor Hospital, a District General Hospital with 612 beds serving a catchment population of 220,000. SUBJECTS: A sample of 50 consecutive elderly patients, with an age range of 65 to 99 years, undergoing transvenous cardiac pacing. MAIN OUTCOME MEASURES: Length of stay in hospital, complications of the pacing procedure, whether a permanent pacemaker was installed, and whether the patient died within 1 month of admission. RESULTS: There was no difference in length of stay between those with a myocardial infarction and those without. Minor complications occurred in three patients (one local infection and two "failures to pace"). Major complications occurred in two patients (septicemia and pneumonia). More patients without a myocardial infarction (86.9%) went on to implantation of a permanent pacemaker than those with an infarction (11.1%, P = 0.001), and fewer of them died (8.7% compared with 48.1%, P = 0.0025). In those patients with a myocardial infarction who died, there was no difference between the proportions who had inferior (7/18) and anterior (5/9) infarctions. CONCLUSION: Cardiac pacing seems to be a safe and reliable procedure in the elderly, although long term morbidity and mortality may be dependent on the presence or absence of myocardial ischaemic disease. Myocardial infarction in the elderly is an event of major significance, carrying with it a high mortality rate, particularly if accompanied by cardiogenic shock and the need for cardiac pacing.  相似文献   
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Biochemical and molecular mechanisms of neuronal cell death are currently an area of intense research. It is well documented that the lumbar spinal motoneurons of the chick embryo undergo a period of naturally occurring programmed cell death (PCD) requiring new gene expression and activation of caspases. To identify genes that exhibit changed expression levels in dying motoneurons, we used a PCR-based subtractive hybridization protocol to identify messages uniquely expressed in motoneurons deprived of trophic support as compared with their healthy counterparts. We report that one upregulated message in developing motoneurons undergoing cell death is the mRNA for amyloid precursor protein (APP). Increased levels of APP and beta-amyloid protein are also detected within dying motoneurons. The predicted peptide sequence of APP indicates two potential cleavage sites for caspase-3 (CPP-32), a caspase activated in dying motoneurons. When peptide inhibitors of caspase-3 are administered to motoneurons destined to undergo PCD, decreased levels of APP protein and greatly reduced beta-amyloid production are observed. Furthermore, we show that APP is cleaved by caspase-3. Our results suggest that differential gene expression results in increased levels of APP, providing a potential substrate for one of the cell death-activated caspases that may ultimately cause the demise of the cell. These results, combined with information on the toxic role of APP and its proteolytic by-product beta-amyloid, in the neurodegenerative disease Alzheimer's, suggest that events of developmental PCD may be reactivated in early stages of pathological neurodegeneration.  相似文献   
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Selective flocculation of fines   总被引:1,自引:1,他引:0  
1 INTRODUCTIONAstheearth’sresourcesarebeingconsumedsteadilyandasdemandformineralproductscontinuestoincrease ,theneedtoutilizelow gradeoresmoreefficientlyhasbecomemoresevere .Thisindeedre sultsinthegenerationofalargequantityoffineparti clesduringminingand…  相似文献   
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The spin-echo nuclear magnetic resonance (NMR) technique together with paramagnetic ion doping are used to study structural parameters of plant samples, such as restricted dimensions, and cell interconnection both through membranes and by cell contact by studying simultaneous restricted diffusion and intercellular water transfer via various pathways. Also, peculiarities of water diffusion on the surface of cell-wall cellulose are studied over a wide range of water content.  相似文献   
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OBJECTIVE: To determine a safe and easy way to estimate body weight (BW) accurately in nonambulant elderly patients. DESIGN: An anthropometric study of ambulant patients. PARTICIPANTS: Two hundred eleven ambulant inpatients, 108 males and 103 females. SETTING: Inpatient departments of the University Department of Geriatric Medicine, Cardiff, Wales, UK. MEASUREMENTS: Skinfold thickness of chin, triceps, forearm, wrist, subscapular, sternal angle, waist, suprailiac, knee, and calf; circumference of arm, forearm, thigh and calf; body weight, chest girth, abdominal girth, upper limb length, leg length, and body weight. Measurements were carried out by means of Harpenden Skin-Fold Caliper, tape measure, and bathroom scale. RESULTS: Measured body weight in males was highly correlated with both arm circumference and chest girth. In females, measured body weight was highly correlated with waist skinfold thickness and thigh circumference. Nomograms for weight estimation in males and females were constructed from the regression equations for these measurements. CONCLUSIONS: Convenient estimation of body weight in nonambulant patients may be carried out using nomograms, which, themselves, may be used as progress sheets to assess the effect of dietary supplementation on body weight.  相似文献   
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