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991.
TF Veneman GW van Dijk E Boereboom H Joore TJ Savelkoul 《Canadian Metallurgical Quarterly》1998,24(3):255-257
We report on pancreatic exocrine dysfunction in families that have the mitochondrial tRNA(Leu)(UUR) gene mutation. These families exhibited maternally inherited diabetes mellitus (DM) and an A to G substitution at nt 3243 of the mitochondrial tRNA(Leu)(UUR) gene (A3243G mutation). Pancreatic necropsy samples from one proband showed accumulation of degenerated mitochondria in pancreatic acinar cells. Pancreatic exocrine dysfunction was recognised by a functional pancreatic study. This study indicates that exocrine pancreatic dysfunction may be associated with the A3243G mutation. 相似文献
992.
AM Padberg TJ Wilson-Holden LG Lenke KH Bridwell 《Canadian Metallurgical Quarterly》1998,23(12):1392-1400
STUDY DESIGN: This was a retrospective study of 500 patients undergoing corrective surgery between 1987 and 1997 for spinal deformity caused by idiopathic scoliosis. OBJECTIVES: To report the sensitivity and specificity of somatosensory-evoked and neurogenic motor-evoked potentials monitoring and the requirements for an intraoperative wake-up test for all idiopathic scoliosis surgeries at a single institution. SUMMARY OF BACKGROUND DATA: Intraoperative monitoring is recommended for use during corrective spinal surgery. Accepted monitoring standards and requirements for an intraoperative wake-up test are still debated. METHODS: The study group consisted of 500 patients undergoing corrective surgery for idiopathic scoliosis between 1987 and 1997. All patients were monitored using somatosensory-evoked and neurogenic motor-evoked potential techniques, using a standard protocol developed at this institution. RESULTS: The false-positive rate (significant data change without postoperative neurologic deficit) was 0.014% (n = 7). The true-positive rate (degradation of data that met warning criteria, with a corresponding postoperative neurologic deficit) was 0.004% (n = 2). No false-negative results (normal data during with a postoperative neurologic deficit) were seen. The sensitivity of combined somatosensory-evoked and neurogenic motor-evoked potential data in predicting neurologic status was 98.6%, and the specificity of normal data predicting normal findings in a neurologic examination was 100%. CONCLUSION: Combined somatosensory-evoked and neurogenic motor-evoked potentials monitoring during idiopathic scoliosis surgery represents a standard of care that obviates the need for an intraoperative wake-up test when reliable data are obtained and maintained. 相似文献
993.
994.
JW Schimmel P Buma D Versleyen R Huiskes TJ Slooff 《Canadian Metallurgical Quarterly》1998,13(4):438-448
Bone defects in total hip arthroplasty revision surgery can be restored with different types of bone graft. The use of impacted morselized allograft chips in combination with cement is the treatment of our choice. To establish the incorporation capacity of the grafts and mechanical stability of the implant, an animal model in the goat was developed. An acetabular defect was created and restored with morselized grafts and a cemented cup. Postoperative performance of the reconstruction was followed both histologically and biomechanically. Histology showed that consolidation of the graft with the host bone bed had occurred within 3 weeks. In the following period a front of vascular sprouts infiltrated the graft. Graft resorption, woven bone deposition, and subsequent remodeling resulted in a new trabecular structure. This structure contained only scarce remnants of the original dead graft material. At the graft-cement interface, graft resorption and new bone formation had resulted in areas of direct vital bone-cement contact. Locally, a soft tissue interface was present. After longer follow-up periods, progressive interface formation and loosening of the cups were found in most animals. Mechanical testing showed that the stability of the reconstruction increased during the first 12 postoperative weeks. Thereafter, the stability decreased, probably by soft-tissue interface formation at the graft cement interface. We conclude that cemented morselized allografts have a high capacity to incorporate. Initial cup stability is adequate to provoke graft incorporation with decreasing stability after the incorporation process has been completed. 相似文献
995.
RR Mehta JH McDermott TJ Hieken KC Marler MK Patel LD Wild TK Das Gupta 《Canadian Metallurgical Quarterly》1998,16(7):2409-2416
PURPOSE: To determine the significance of plasma c-erbB-2 levels to assess the extent of disease spread and to predict the response to chemotherapy in node-positive breast cancer patients. METHODS: We determined plasma levels of c-erbB-2 in 79 stages II and III breast cancer patients who received cyclophosphamide, methotrexate, and flourouracil (CMF)/cyclophosphamide, methotrexate, fluorouracil, vincristine, and prednisone (CMFVP) chemotherapy. All patients had a minimum follow-up of greater than 60 months or until disease recurrence. Plasma samples were obtained before and after chemotherapy. Plasma c-erbB-2 levels were quantified by enzyme-linked immunoassay. c-erbB-2 levels were analyzed in relation to the patients' axillary lymph node status, menopausal status, disease status, disease-free survival (DFS), and steroid receptor status of tumor. RESULTS: Plasma c-erbB-2 levels varied widely in breast cancer patients. In general, when all patients were included in the analyses, plasma c-erbB-2 levels before chemotherapy correlated significantly with the number of positive axillary lymph nodes and with postchemotherapy c-erbB-2 levels. No association was observed between pre- or postchemotherapy c-erbB-2 levels and other variables (patients' age at diagnosis, receptor status of the tumor, or disease status). The prognostic significance of different factors (ie, nodal status [one to three v > three positive nodes], menopausal status [pre- v postmenopausal women], estrogen receptor [ER] status [ER+ v ER-], and pre- and postchemotherapy c-erbB-2 levels) in predicting DFS was determined in all study patients. Among the variables examined, nodal status was the strongest predictor of DFS in these patients. The second most significant prognostic marker was postchemotherapy c-erbB-2 level. Prechemotherapy c-erbB-2 levels showed prognostic significance for DFS in a subset of breast cancer patients (ie, patients with > three positive nodes). Patients with greater than three positive lymph nodes and those with greater than 100 fmol/mL of plasma c-erbB-2 levels before therapy had significantly shorter DFS than did those patients with 100 fmol/mL or less c-erbB-2 levels. CONCLUSION: In breast cancer patients, determination of c-erbB-2 levels before therapy is an important biomarker to assess the extent of disease spread in the lymph nodes. Postchemotherapy c-erbB-2 levels are also a prognostic indicator for DFS in patients who receive chemotherapy. Finally, in a subgroup of patients with greater than three positive nodes, prechemotherapy c-erbB-2 levels are a prognostic marker for response of patients to standard chemotherapy. 相似文献
996.
997.
Spinal injuries resulting from falls out of tree stands are often associated with concomitant neurologic deficit, prolonged hospitalization, and long-term disability. The purpose of this study was to review the types of spinal injuries that resulted from falls from hunting tree stands. We retrospectively reviewed 27 patients who came to our institution for treatment of spine injuries related to tree-stand accidents between 1981 and 1997. Eleven percent of the falls were alcohol related. Mean height of the fall was 19.6 feet (range, 10 to 35 feet). There were 17 burst fractures, 8 wedge compression fractures, 4 fractures involving the posterior elements, and 1 coronal fracture of the sacral body. Significant neurologic injury occurred in 12 patients (44%). Sixteen patients (59%) had associated injuries. Nine patients (33%) had open reduction, internal fixation, and fusion of their spine fractures. One patient was treated with a halo jacket. The remaining patients were treated in rigid, molded, polypropylene thoracolumbar orthoses or lumbosacral corsets. Accidental falls from tree stands may result in significant spinal fractures often associated with concomitant neurologic injury, extended hospitalization, and permanent disability. Many of these injuries may be prevented through aggressive hunter safety education. 相似文献
998.
999.
TJ Barstow AM Scremin DL Mutton CF Kunkel TG Cagle BJ Whipp 《Canadian Metallurgical Quarterly》1996,28(10):1221-1228
We examined the ability of patients with spinal cord injury to undergo adaptations to chronic exercise training (cycle ergometry) invoked by functional electrical stimulation (FES) of the legs. Nine such patients performed incremental and constant work rate exercise before and after exercise training. Exercise sessions averaged 2.1 +/- 0.4/wk, and consisted of 30 min/session of continuous FES recumbent cycling with increasing work rate as tolerated. Peak VO2 and peak work rate significantly improved with training. Peak VO2 was significantly correlated with peak heart rate both before and after training (r = 0.97 pre and 0.85 post, P < 0.01 for both). The time course of the VO2, VCO2 and VE responses to constant-load exercise (unloaded cycling) and in recovery (mean response time MRT) were very long prior to training, and became significantly faster following training. However, there was no correlation between percentage improvement in either MRTon or MRToff for VO2 and the percentage increase in peak VO2. Exercise tolerance in these patients with spinal cord injury appears to be a direct function of the ability to increase heart rate. Further, exercise training can elicit significant improvements in both exercise tolerance and in gas exchange kinetics, even when performed only twice per week. However, these improvements may be accomplished by different mechanisms. 相似文献
1000.
MA Freyaldenhoven PA Lehman TJ Franz RV Lloyd VM Samokyszyn 《Canadian Metallurgical Quarterly》1998,11(2):102-110
The nursing profession places a high value on the acquisition of autonomy as a requisite for professional status. Although the literature is replete with studies that examine autonomy and nurses, methods and results often are inconsistent and inconclusive. Review of the literature reveals ambiguous or absent definitions of autonomy. Nursing commonly confuses autonomy with related concepts such as authority, accountability, power, professionalism, and independence. A concept analysis of autonomy is done using Walker and Avant's modification of Wilson's analysis procedure. This highly abstract concept emerges as a discrete, empirically definable term referring to a potential human quality in an existing state. The analysis includes antecedents, consequences, defining attributes, model and borderline cases, and empirical referents. 相似文献