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Embryoscopic diagnosis of conjoined twins presenting with a missed abortion has never been reported. The morphological and pathological examinations, and the exact time of death in the conceptus of a missed abortion are seldom clearly delineated. The newly developed field of embryoscopy has created a new frontier in early embryonic/fetal visualization and is able to confirm the sonographic diagnosis. In this report, we used a transcervical endoscope to verify conjoined twins (thoraco-omphalopagus) in a 10-week missed abortion. Based on the size and the external features of the dead embryo, which exhibited developmental arrest at nine weeks and three days of menstrual age, we estimated that the embryo had died four days before examination. The whole procedure proceeded smoothly without any immediate complications. 相似文献
33.
Suprachiasmatic nucleus organization 总被引:1,自引:0,他引:1
OBJECTIVE: To assess the effect of a combined exercise and motivation program on the compliance and level of disability of patients with chronic and recurrent low back pain. DESIGN: A double-blind prospective randomized controlled trial. SETTING: Physical therapy outpatient department, tertiary care. PATIENTS: Ninety-three low back pain patients were randomly assigned to either a standard exercise program (n = 49) or a combined exercise and motivation program (n = 44). INTERVENTIONS: Patients were prescribed 10 physical therapy sessions and were advised to continue exercising after treatment termination. The motivation program consisted of five compliance-enhancing interventions. Follow-up assessments were performed at 3 1/2 weeks, 4 months, and 12 months. MAIN OUTCOME MEASURES: Disability (low back outcome score), pain intensity, physical impairment (modified Waddell score, fingertip-to-floor distance, abdominal muscle strength), working ability, motivation, and compliance. RESULTS: The patients in the motivation group were significantly more likely to attend their exercise therapy appointments (p = .0005). Four and 12 months after study entry there was a significant difference in favor of the motivation group with regard to the disability score (p = .004) and pain intensity (p < or = .026). At 4 months, there was a significant advantage for the motivation group in the fingertip-to-floor distance (p = .01) and in abdominal muscle strength (p = .018). No significant differences were found in motivation scores, self-reported compliance with long-term exercise, and modified Waddell score. In terms of working ability, there was a trend favoring the combined exercise and motivation program. CONCLUSION: The combined exercise and motivation program increased the rate of attendance at scheduled physical therapy sessions, ie, short-term compliance, and reduced disability and pain levels by the 12-month follow-up. However, there was no difference between the motivation and control groups with regard to long-term exercise compliance. 相似文献
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JJ Worthington MH Pollack MW Otto RY McLean G Moroz JF Rosenbaum 《Canadian Metallurgical Quarterly》1998,34(2):199-205
OBJECTIVE: To assess the effect of the relief of obstruction on the ultimate function of the affected renal unit in urinary tuberculosis, and to identify predictors of functional recoverability. PATIENTS AND METHODS: Of a total of 82 patients with urinary tuberculosis presenting over 7 years, 38 with evidence of upper tract obstruction were analysed. All patients were assessed with pre-operative excretory urography, urinary mycobacterial cultures and serum chemistry. Patients with subnormally functioning kidneys were assessed with baseline renal scans. Preliminary intervention in the form of JJ stenting or percutaneous nephrostomy (PCN) was carried out in patients with reasonable renal function. Function was reassessed after 4 weeks to detect evidence of improvement and factors which could affect the outcome were determined. RESULTS: Thirty-eight patients had documented upper tract obstruction, of whom six had bilateral obstruction (total of 44 renal units). Ten renal units were not functioning at presentation, with a mean (SD) glomerular filtration rate (GFR) of 3.0 (5.73) mL/min, and no preliminary intervention was performed. In the remaining 34, preliminary intervention was carried out before definitive surgery (JJ stenting in 14, PCN in 15 and PCN followed by antegrade JJ stenting in five); 21 of these renal units were salvaged but 13 were lost despite overcoming the obstruction. Three of the 13 units deteriorated from having acceptable pre-treatment GFRs to becoming non-functional. Good renal cortical thickness, a low grade of renal involvement (Semb 1 or 2), the presence of more distal disease in the form of ureteric stricture and a GFR of > 15 mL/min were good predictors of renal recovery after diversion. CONCLUSIONS: The loss of some renal units seems inevitable in patients with urinary tuberculosis, despite advances in chemotherapy. Having pre-operative predictors of renal recovery may ensure optimal patient selection, thereby reducing the number of procedures and economic burden on the patient who does not require intervention. 相似文献
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Recombinant proteins containing four cysteines at the i, i + 1, i + 4, and i + 5 positions of an alpha helix were fluorescently labeled in living cells by extracellular administration of 4',5'-bis(1,3, 2-dithioarsolan-2-yl)fluorescein. This designed small ligand is membrane-permeant and nonfluorescent until it binds with high affinity and specificity to the tetracysteine domain. Such in situ labeling adds much less mass than does green fluorescent protein and offers greater versatility in attachment sites as well as potential spectroscopic and chemical properties. This system provides a recipe for slightly modifying a target protein so that it can be singled out from the many other proteins inside live cells and fluorescently stained by small nonfluorescent dye molecules added from outside the cells. 相似文献
38.
SC Muluk VS Muluk H Sugimoto RY Rhee J Trachtenberg DL Steed F Jarrett MW Webster MS Makaroun 《Canadian Metallurgical Quarterly》1999,29(2):208-14; discussion 214-6
PURPOSE: The purpose of this study was to delineate the natural history of the progression of asymptomatic carotid stenosis. METHODS: In a 10-year period, 1701 carotid arteries in 1004 patients who were asymptomatic were studied with serial duplex scans (mean follow-up period, 28 months; mean number of scans, 2.9/patient). At each visit, stenoses of the internal carotid artery (ICA) and the external carotid artery (ECA) were categorized as none (0 to 14%), mild (15% to 49%), moderate (50% to 79%), severe (80% to 99%), preocclusive, or occluded. Progression was defined as an increase in ICA stenosis to >/=50% for carotid arteries with a baseline of <50% or as an increase to a higher category of stenosis if the baseline stenosis was >/=50%. The Cox proportional hazards model was used for data analysis. RESULTS: The risk of progression of ICA stenosis increased steadily with time (annualized risk of progression, 9.3%). With multivariate modeling, the four most important variables that affected the progression (P <.02) were baseline ipsilateral ICA stenosis >/=50% (relative risk [RR], 3.34), baseline ipsilateral ECA stenosis >/=50% (RR, 1.51), baseline contralateral ICA stenosis >/=50% (RR, 1.41), and systolic pressure more than 160 mm Hg (RR, 1. 37). Ipsilateral neurologic ischemic events (stroke/transient ischemic attack) occurred in association with 14.0% of the carotid arteries that were studied. The progression of ICA stenosis correlated with these events (P <.001), but baseline ICA stenosis was not a significant predictor. CONCLUSION: In contrast to recently published studies, we found that the risk of progression of carotid stenosis is substantial and increases steadily with time. Baseline ICA stenosis was the most important predictor of the progression, but baseline ECA stenosis also was identified as an important independent predictor. Contralateral ICA stenosis and systolic hypertension were additional significant predictors. We found further that the progression of ICA stenosis correlated with ischemic neurologic events but not baseline stenosis. The data provide justification for the use of serial duplex scans to follow carotid stenosis and suggest that different follow-up intervals may be appropriate for different patient subgroups. 相似文献
39.
RY Poon K Yamashita JP Adamczewski T Hunt J Shuttleworth 《Canadian Metallurgical Quarterly》1993,12(8):3123-3132
Activation of the cyclin-dependent protein kinases p34cdc2 and p33cdk2 requires binding with a cyclin partner and phosphorylation on the first threonine residue in the sequence THEVVTLWYRAPE. We present evidence that this threonine residue, number 160 in p33cdk2, can be specifically phosphorylated by a cdc2-related protein kinase from Xenopus oocytes called p40MO15. Binding to cyclin A and phosphorylation of this threonine are both required to activate fully the histone H1 kinase activity of p33cdk2. In cell extracts, a portion of p40MO15 is found in a high molecular weight complex that is considerably more active than a lower molecular weight form. Wild-type MO15 protein expressed in bacteria does not possess kinase activity, but acquires p33cdk2-T160 kinase activity after incubation with cell extract and ATP. We conclude that p40MO15 corresponds to CAK (cdc2/cdk2 activating kinase) and speculate that, like p33cdk2 and p34cdc2, p40MO15 requires activation by phosphorylation and association with a companion subunit. 相似文献
40.
Dual control of heat shock response: involvement of a constitutive heat shock element-binding factor
Heat shock factor (HSF) has been implicated as the key regulatory protein in the heat shock response. Our studies on the response of rodent cells to heat shock or sodium arsenite indicate that a high level of HSF-DNA-binding activity, by itself, is not sufficient for the induction of hsp70 mRNA synthesis; furthermore, a high level of HSF binding is also not necessary for this induction. Analysis of the binding of protein factors to the heat shock element (HSE) in extracts of stressed rodent cells indicates that the regulation of heat shock response involves the heat-inducible HSF and a constitutive HSE-binding factor. Our results also suggest that overexpression of human hsp70 may decrease the level of heat-induced HSF-HSE-binding activity in rat cells. 相似文献