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101.
KH Scholz JL Dubois-Rande P Urban MC Morice D Loisance RW Smalling HR Figulla 《Canadian Metallurgical Quarterly》1998,82(9):1107-10, A6
The percutaneous Hemopump showed beneficial effects during coronary angioplasty in 32 high-risk patients with unloading of the left ventricle during ischemia and maintaining cardiac output with mean aortic pressures of 50 mm Hg in case of cardiac arrest (3 patients). High procedure-related morbidity (occlusion of femoral artery in 2 patients; bleeding with need of transfusion in 4 patients) and mortality (4 of 32 patients) rates demonstrate the need for a very careful selection of patients. 相似文献
102.
C Fitzek J Tintera W Müller-Forell P Urban F Th?mke S Fitzek HC Hopf P Stoeter 《Canadian Metallurgical Quarterly》1998,40(12):778-782
We performed MRI, including diffusion-weighted imaging, in 15 patients with recurrent strokes with acute ischaemia and at least one old lesion according to the clinical history and/or CT. Routine MRI showed similar signal intensity changes in both situations. Diffusion-weighted images, however, were positive in all acute or subacute infarcts. The high signal of acutely disturbed diffusion due to intracellular oedema could also be identified in small brain stem lesions. Spatial resolution was increased by applying separate gradients in each axis instead of creating anisotropy-independent trace images. 相似文献
103.
C Dumontier V Maylin A Sautet E Lenoble T Urban A Apoil 《Canadian Metallurgical Quarterly》1996,82(7):668-671
A 47 years-old man presented an atraumatic, spontaneous index flexor tendons rupture. This patient has been treated two years ago for a pulmonary tuberculosis. At surgery, the flexor tendons were infiltrated by a granuloma. Histologic examination was compatible with tuberculosis sequelae. According to literature review, this is the second reported case of a tendon rupture due to tuberculosis granuloma. 相似文献
104.
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106.
T Urban C Chastang F Vaylet M Mathieu P Leclerc D Paillotin B Lebeau 《Canadian Metallurgical Quarterly》1998,114(6):1538-1541
STUDY OBJECTIVE: To determine the prognostic significance of supraclavicular lymph node (SCLN) involvement in small cell lung cancer. MATERIALS AND METHODS: Patients (1,370) with small cell lung cancer were included in four consecutive clinical trials and classified as having either limited or extensive forms of disease using the Veterans Administration staging system. RESULTS: SCLN was present in 17% of patients (n = 234). Median survival was 258 days for patients with SCLN (n = 234) and 297 days for patients without SCLN (n = 1136) (p = 0.002). SCLN involvement was correlated with the presence of distant metastases at baseline (169 vs 65, p = < 0.001). Median survival was 375 days for patients with limited forms without SCLN (n = 529), 332 days for those with limited forms with SCLN (n = 65) (p = 0.12), 244 days for those with extensive forms without SCLN (n = 604), and 228 days for those with extensive forms with SCLN (n = 169) (p = 0.94). The 2-year survival rates were 17%, 12%, 2%, and 4%, respectively. Cox models confirmed that SCLN did not provide any significant additional prognostic information. CONCLUSION: SCLN is highly correlated with extensive forms explaining its overall prognostic value. In limited disease, SCLN is only a minor poor prognostic factor, not justifying any amendment to the staging system currently used. 相似文献
107.
Ovarian organ culture was used to study the influence of various gonadotropin hormones (100 ng FSH, 100 ng LH, 100 ng LH added together with 100 ng FSH; 1 i.u. hCG or 10 i.u. PMSG) on growth and development of follicles as well as on steroid secretion by ovaries of postnatal, 15-day-old mice. Ovaries were aseptically removed and single organs were placed on a piece of lens paper which was supported by a stainless steel grid in the small organ culture dish. The cultures were maintained in medium M199 supplemented with 5% of calf serum in a CO2 incubator at 37 degrees C. The morphological changes and steroid secretion measured by appropriate RIAs were studied. The stages of follicular development and the incidence of particular types of follicles were scored. Progesterone and estradiol were detected in the medium by radioimmunoassay. Differences between control and gonadotropin stimulated ovaries were found in the number of the ovarian follicles in more advanced maturation stages. There was increased number of multilaminar and antral follicles in FSH and FSH plus LH treated cells. The adding of gonadotropin hormones to the culture medium stimulated significantly progesterone secretion. The most significant effect was observed in media of cultures treated with LH and hCG. As to estradiol secretion the highest stimulatory effect was seen in cultures supplemented with FSH alone, together with LH and with PMSG. The organ culture technique applied in the current study could be a suitable model of studying the interaction of various factors as well as its effect on ovarian differentiation and on selection of dominant follicles. This system allows maintaining the structural integrity of the whole ovary, thus in the physiological functional status of the organ. 相似文献
108.
V. P. Alushev A. S. Parasyna S. N. Popov G. S. Romanov V. V. Urban 《Journal of Engineering Physics and Thermophysics》1985,48(4):500-504
Results are presented of experimental and theoretical investigations and the possibility is shown of producing a laboratory source of a dense low-temperature plasma.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 4, pp. 670–675, April, 1985. 相似文献
109.
The purpose of this study was to determine if ultrasonographic measurement of multiple cross-sectional areas combined with linear dimensions of the bladder could be used as a method of estimating bladder volume in the dog, and, if so, to compare the accuracy of this estimation with that described previously using linear measurements alone. Fifty-two live dogs undergoing investigation for urological disease and 37 fresh canine cadavers were used for bladder volume determination. Maximal length, depth, width, and area were measured from the maximal longitudinal and transverse sonograms in each living animal. In cadavers, the cross-sectional area of the longitudinal section of the bladder was measured at one centimeter intervals, and the measurements were summed. Based on sequential partial regression analysis, the cross-sectional area of the longitudinal section of the bladder and length were the best predictors of actual bladder volume in living animals. However, based on the cadaver experiment, the best predictor of actual bladder volume was summed parasagittal area alone, and, in cadavers, this was a much better predictor of actual bladder volume than the combination of the cross-sectional area of the longitudinal section of the bladder and length. The formula derived in living dogs using the cross-sectional area of the longitudinal section of the bladder and length gave a less accurate estimation of bladder volume than a previously published formula where only linear measurements were used. 相似文献
110.
E Urban MW King R Guidoin G Laroche Y Marois L Martin A Cardou Y Douville 《Canadian Metallurgical Quarterly》1994,40(2):145-156
In recent years some clinical reports have associated suture failures with polypropylene monofilaments. Therefore there is interest in developing an alternative suture material that is less thrombogenic than polyester and similar in handling characteristics but less prone to mechanical failure than polypropylene. To this end, Peters Laboratoire Pharmaceutique has developed a new monofilament suture material from polyvinylidene fluoride (PVDF), which has been subjected to a special treatment to modify its crystalline form and level of crystallinity. The purpose of this study was to evaluate its mechanical, chemical, and biologic properties and to compare its performance, in a peripheral vascular application, to that of a polypropylene control. A series of in vitro tests were performed to study the morphology, tensile properties, creep, surface chemistry, thermal characteristics, and resistance to iatrogenic trauma. In addition, an in vivo trial was undertaken in which vascular prostheses anastomosed with either PVDF or polypropylene sutures were implanted as a thoracoabdominal bypass for 6 months in the dog. Histologic and degradation analyses were performed on the explants. The results from the mechanical tests on 4-0, 5-0, and 6-0 PVDF and polypropylene sutures demonstrated that although both materials have similar breaking strengths, the PVDF has a higher extension at break, has less delayed extension when under tensile creep testing, and suffers less trauma than the polypropylene when compressed by a standard needle holder. While chemical analyses found evidence of surface oxidation on both types of sutures, thermal analysis confirmed that the level of crystallinity of the PVDF polymer is higher than that of the polypropylene control. During the pilot study in animals, PVDF sutures were found to have good handling and frictional characteristics that facilitated the tying of knots. Histologic analysis of the explants found no inflammatory cells in the tissue surrounding either the PVDF or polypropylene sutures, and scanning electron microscopic examination of the cleaned suture surfaces found no evidence of degradation during 6 months in vivo. Though preliminary in nature, these findings indicate that monofilament sutures made from PVDF provide an attractive alternative to those made from polypropylene for use in cardiovascular surgery. In addition to providing acceptable in vivo behavior and being easy to manipulate and more resistant to iatrogenic injury, PVDF materials can be sterilized by beta or gamma radiation and so can reduce dependence upon ethylene oxide and chlorofluorohydrocarbons. 相似文献