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181.
182.
K Wilhelm H Schild C Düber M Mitze J Schlegel J Lorenz 《Canadian Metallurgical Quarterly》1996,164(6):496-501
PURPOSE: Stent implantation was used to treat patient with malignant tracheobronchial obstructions to determine the effectiveness in producing symptomatic palliation. METHODS: 18 patients (15 men and three women; median age 57 years) with malignant tracheobronchial stenosis were treated by application of metal stents (15 Palmaz-, 10 Gianturco-, 4 Wallstents). The indication for stent implantation was given in 13 patients by clinically significant dyspnea, besides in 5 patients by therapy resistant postobstructive pneumonia. RESULTS: In 17 patients correct positioning of the stents was achieved and the symptoms completely disappeared until tumor related death. Median survival was 137 days (min. 10 days to max. 322 days). In one patient symptoms recurred three months after stent implantation. CONCLUSION: The application of metal stents in patient with malignant tracheobronchial obstruction appears to be a useful palliation procedure. The treatment was well tolerated and very effective. 相似文献
183.
Thirty individual human milk samples were gathered from five main towns in Jordan. They were mixed to six pooled samples and analyzed for PCDD and PCDF. All examined samples were contaminated with 1,2,3,4,6,7,8-HeptaCDD (3.2-96.0 ng/kg fat) and OctaCDD (29.0-147 ng/kg fat). The calculated TEQ (BGA)-values range between 0.26 and 60.32 ng TEQ/kg fat, which are all above the calculated tolerable concentration of 0.19 ng TEQ/kg milk fat. 相似文献
184.
C Hasse A Zielke G Kl?ck A Schlosser P Barth U Zimmermann H Sitter W Lorenz M Rothmund 《Canadian Metallurgical Quarterly》1998,22(7):659-665
Acute lung injury is a frequent clinical occurrence following blood loss and trauma. The nature of this injury remains poorly understood. OBJECTIVE: To examine the relative parenchymal and intra-alveolar distribution of inflammation in a rat model of hemorrhage and resuscitation. METHODS: Rats were anesthetized and subjected to hemorrhage followed by resuscitation with shed blood and saline. Myeloperoxidase activity of lung homogenates and cytology of bronchoalveolar lavage fluid were used to measure total lung and intra-alveolar neutrophil invasion. Extravasation of i.v.-administered [125I]-albumin was used to determine total lung and alveolar permeability. Permeability results were analyzed using their base-10 logarithmic transformations. RESULTS: 86 animals were studied. Whole-lung myeloperoxidase activity was increased (control = 0.34 +/- 0.16 units, injured = 0.84 +/- 0.43 units, p < 0.01), while there was no difference in intra-alveolar leukocyte counts (injured = 1.85 +/- 1.30 x 10(5)/mL, control = 2.44 +/- 1.75 x 10(5)/mL, p = 0.40), suggesting that the cellular component of the injury was more severe in the intravascular and interstitial spaces. There was a strong trend toward increased permeability in the interstitial compartment, and a significant increase in permeability in the intra-alveolar compartment (whole-lung permeability: control = -0.27 +/- 0.19 units, injured = 0.10 +/- 0.55 units, p = 0.06; alveolar permeability: control = -2.00 +/- 0.47 units, injured = -1.32 +/- 0.49 units, p < 0.01), suggesting that the loss of integrity to macromolecules was not limited to the interstitium. CONCLUSION: Hemorrhage and resuscitation resulted in an acute lung injury characterized by extravasation of intravascular protein into both the interstitium and the intra-alveolar space. Neutrophil invasion of the lung was demonstrable only in the interstitial compartment. 相似文献
185.
J Schlegel G Meng M Kieser J Lorenz K Kienast R Ferlinz 《Canadian Metallurgical Quarterly》1994,48(11):799-802
For the performance of clinical drug trials in the therapy for bronchial hyperresponsiveness, unspecific inhalatory provocation tests are generally employed to judge therapeutic success. In particular, the parameter-specific provocation doses are considered to be the main target values. However, it must be considered that these provocation doses are not equally calculable for every patient in the same way and at any examination time. This leads to the fact that the number of evaluable case studies is often appreciably lower than the number of test participants and that a meaningful therapy group comparison may even not be possible under certain circumstances. An evaluation model is presented here in order to fully exploit the obtained data; in this the percentile changes of the function parameters (estimated by linear regression) at a defined dose of the provocation substance are analyzed. In analogy, a survival time model and, as a supplement, a best case/worst case analysis are performed for further statistical evaluation. With the present procedure, an evaluation with inclusion of all test participants is possible. In contrast to the previously used evaluation procedures, this allows a reliable statistical confirmation of the results of clinical tests in the therapy for bronchial hyperresponsiveness. 相似文献
186.
The LSP test method was used to compare various surface treatments of spinal rods for dorsal spine implant systems. This test method allowed a fast testing. Result were given after one or two weeks in comparison to 6 to 8 months. Rods made of two different cp‐Titanium materials ( Ti‐2 and Ti‐4) were tested. Best results with a LSP value of 167 Mio. were achieved with Ti‐4 material, shot peened with steel balls and glass beads. In comparison the lowest LSP value showed 81 Mio with Ti‐2 material shot peened with glass beads only. This kind of high speed testing reduced the typical development period from two years to at least 6 months. 相似文献
187.
188.
Th. Lorenz J. Diekmann K. Frueh R. Hiddessen J. Moeller J. Niehoff K. Schügerl 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1987,38(1):41-53
Penicillin V was produced in a 98-dm3 tower loop reactor using a production strain of Penicillium chrysogenum in pellet form. By using control devices, the aeration, the only energy input in a tower loop reactor, decreased by an average of 75%. The amounts of precursor substance (phenoxyacetic acid), acid, base, ammonium sulfate and urea, added during the penicillin fermentation process, were reduced by applying an automatic analysing system to the process. 相似文献
189.
LD Berthold M Hoppe H K?nig B Saar HJ Wagner W Lorenz KJ Klose 《Canadian Metallurgical Quarterly》1998,169(6):585-589
Triple pelvic osteotomy reorients the acetabulum relative to the pelvis in order to improve acetabular coverage of the femoral head in cases of acetabular dysplasia. We undertook a radiostereometric analysis (RSA) on 6 osteotomized cadaver hips to determine the actual three-dimensional reorientation obtained. The centers of the femoral head were all translated posteriorly between 11 and 41 mm, and distally up to 13 mm. 4 were lateralized up to 8 mm, and 2 were medialized up to 5 mm. All acetabuli rotated anteriorly about the lateral to medial axis (X-axis), and 4 rotated outwards around the distal to proximal axis (Y-axis). The correlations between measurements performed on conventional anteroposterior radiographs and the RSA measurements were poor: variations in the lateral-medial direction ranged from -16 to +6 mm, and in the distal-proximal direction between -10 and +12 mm. The changes in orientations measured will significantly affect the load across the hip joint, since the dimensions of the pelvis change and the moment arms of the muscles, their lengths and lines of action are changed as well. We conclude that, with the procedures presently performed, the loads across the hip joint are bound to change, and that the reorientation can hardly be checked with conventional radiographs. 相似文献
190.