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91.
The strength of surface-damaged fibers was studied by means of a computer simulation experiment based on the Monte-Carlo method
using a simple model which assumes that the surface flaws can be regarded as mode I notches on fiber surfaces, the strength
of undamaged fibers obeys the Weibull distribution function, and the largest flaw determines the strength of damaged fibers.
Normal and exponential distribution functions were taken as the flaw size distribution function. By employing the present
simulation method, the effects of average flaw size, coefficient of variation of flaw size, density of flaws, and gage length
on average strength and its coefficient of variation were studied. It was found that the surface-damaged fibers can retain
their full strength only when the average flaw size is small, the coefficient of variation of flaw size is small, density
of flaw size is low, and gage length is short. Otherwise the average strength of damaged fibers was reduced seriously. It
was emphasized that the scatter of size of flaws and density of flaws strongly affect the strength of fibers as well as flaw
size and gage length. 相似文献
92.
93.
Three cases of pulmonary leiomyosarcoma were presented. The characteristic clinical features were described with review of literature. In comparison with bronchogenic carcinoma, the leiomyosarcoma has some characteristics: 1) On chest X-ray, it usually appears as a sharply demarcated, even density round mass, growing rapidly within the lung, it rarely accompanies with hilar or mediastinal lymph node metastasis. 2) The preoperative cytological or pathological diagnosis is difficult either by sputum smear or by bronchoscopic biopsy or by fine needle percutaneous aspiration biopsy. 3) Pathological differential diagnosis of leiomyosarcoma of lung from anaplastic lung cancer is difficult. In conclusion, the primary pulmonary leiomyosarcoma is a rare malignant tumor, detecting the present illness seriously, paying attention to the chest X-ray films characterize, early surgical resection is the only way to get diagnosis and effective treatment method. 相似文献
94.
S Akiya Y Nishio K Ibi H Uozumi H Takahashi T Hamada A Onishi H Ishiguchi Y Hoshii M Nakazato 《Canadian Metallurgical Quarterly》1996,103(7):1106-1110
BACKGROUND: Finnish-type familial amyloidosis (FAP-IV) is an autosomal, dominantly inherited disorder characterized by progressive polyneuropathy and lattice corneal dystrophy type II. The vast majority of families with this disorder originated from Finland. Only two families, in neighboring districts, have been reported in Japan previously. METHODS: The authors report two additional Japanese patients with FAF-IV. The proband, a 70-year-old man, had decreased perspiration and abnormal facial muscle movement. Results of neurologic examination showed bilateral facial and hypoglossal nerve palsies, and an autonomic disturbance, including orthostatic hypotension and dysfunction of perspiration. Histochemical, immunohistological, and DNA studies confirmed the diagnosis of FAP-IV. RESULTS: Results of ophthalmologic examination showed asymptomatic lattice corneal dystrophy of both eyes, but the appearance of the cornea was different from that described in the patients from Finland. Lattice lines in the authors' patient were very fine, short, and glassy and could be observed with indirect retroillumination, but might be missed with direct illumination by the slit-lamp microscope. The proband's younger half-sister, a 68-year-old woman, showed clinical findings and laboratory data similar to those of the proband. CONCLUSION: The authors report two Japanese patients with lattice corneal dystrophy type II related to FAP-IV. This is the third Japanese family with this disorder, and there is no familial relationship to the two previously reported families in Japan. 相似文献
95.
M Nishio M Ohata H Kobayashi T Suruda K Uetani M Funasako K Nishio Y Sasaki N Saijo 《Canadian Metallurgical Quarterly》1993,23(5):284-290
We performed a phase I trial to evaluate the toxicity and the maximum tolerated dose of high dose epirubicin on a three-consecutive-day schedule on Japanese patients with advanced non-small cell lung cancer. Fourteen patients were entered in the study. At least three patients were assigned to each different dose level. Epirubicin was given intravenously daily for three day by bolus injection. The dose was started at 60 mg/m2/course and escalated by 30 mg/m2/course. Granulocytopenia was found to be the dose limiting toxicity with a maximum tolerated dose of 150 mg/m2/course. Thrombocytopenia and non-hematological toxicities were mild and well tolerated. The maximum tolerated dose was lower than that in Europe and Canada. Partial responses were observed in two out of five patients on 150 mg/m2/course. The recommended phase II dose for high dose epirubicin was demonstrated to be 120 mg/m2/course. A further dose-escalating study of epirubicin in conjunction with the administration of granulocyte colony stimulating factor is scheduled for the determination of its antitumor activity in non-small cell lung cancer. 相似文献
96.
M. Fujii H. Iwanaga N. Shibata H. Ogawa M. Nishio 《Journal of Materials Science》1993,28(15):4068-4072
ZnSe crystals were grown by a vapour transport method on a GaAs substrate with a (111) A or (¯1¯1¯1) B surface. Crystals obtained on the (111) A surface of the substrate were fine crystals and hexagonal plates. Whereas crystals grown on the (¯1¯1¯1) B were uniform thin films on which trigonal hills and trigonal pyramids developed. These crystallites had a complicated morphology. In addition, the hill and pyramid grown on the (¯1¯1¯1) B surface contained rotation twins around a polar axis parallel to the growth direction or around the other polar axes. 相似文献
97.
Aspirin and sodium salicylate enhance to a similar extent the production of nitric oxide (NO) in cultured smooth muscle cells following stimulation by interleukin-1beta (IL-1beta). The similar potencies of aspirin and sodium salicylate indicate that acetylation of cellular macromolecules is not essential for the enhancement of NO production. The failure of added prostaglandin E2 (PGE2) or Thromboxane A2 (TXA2) to overcome the effects of aspirin or sodium salicylate indicates that these effects are not simply the result of inhibition of prostaglandin synthesis. The enhancement of NO production occurs dependent of the effects of these agents on induction of inducible nitric oxide synthase (iNOS) expression by IL-1beta. Aspirin and sodium salicylate enhance the induction of iNOS expression by IL-1beta. We previously reported that pretreatment of vascular smooth muscle cells (VSMCs) with high glucose decreased the response of the cells by IL-1beta, that is, the induction of iNOS expression and NO production. We investigated the effect of aspirin and sodium salicylate on the response by IL-1beta of VSMCs pretreated with high glucose (25 mM). Aspirin and sodium salicylate ameliorate the down-regulation of iNOS expression and the decrease of NO production caused by pretreatment with high glucose (25 mM). These results suggest a possible therapeutic role in atherosclerotic disease and diabetes mellitus for aspirin and sodium salicylate by enhancing the level of iNOS expression and NO production. 相似文献
98.
Miyazaki Kentaro; Kadono Shojiro; Sakurai Masahiro; Moriyama Hideaki; Tanaka Nobuo; Oshima Tairo 《Protein engineering, design & selection : PEDS》1994,7(1):99-102
3-Isopropylmalate dehydrogenase from an extreme thermo-phile,Thermus thermophUus HB8, was chemically modified with tetranitromethanewhich nitrated 1.5-2.0 Tyr residues per subunit. The nitrationwas biphask and parallel to the loss of activity. The modifiedresidue in the first phase was identified to be Tyr36, whichis distantly located from the active site of the enzyme. Thefunction of Tyr36 was investigated by site-specific replacementwith Phe. The Michaelis constant for the substrate or co-enzymewas not altered by the replacement, whereas the catalytic constantdecreased down to -5%. X-ray analysis of the mutant enzyme revealedthat Arg94 moved the largest distance among the active siteresidues, that is, the NH1 and NH2 of the guanidino group moved1.11 and 1.32 Å respectively. The results suggest thatArg94 is responsible for the enzyme catalysis 相似文献
99.
The influence of non-uniform fibre spacing on the strength of unidirectional fibre-reinforced metal matrix composites was
studied by means of a Monte-Carlo computer simulation experiment. The influence of yield stress of the matrix and scatter
of the fibre strength on the strength of composites were also studied for both uniform and non-uniform fibre spacings. It
was demonstrated that (1) the strength of composites with non-uniform fibre spacing is lower than that with uniform spacing
due to the high stress concentration arising from the breakage of fibres, and (2) the reduction in strength of composites
due to the non-uniformity increases with increasing scatter of fibre strength. For both cases of uniform and non-uniform spacings,
the following tendencies were observed : (a) the strength of composites increases but then decreases with increasing yield
stress of matrix, (b) it is very sensitive to yield stress of the matrix when the scatter of fibre strength is large but not
when it is small, and (c) it decreases but then increases with increasing scatter of fibre strength when the yield stress
of the matrix is high, while it decreases monotonically with increasing scatter of fibre strength when the yield stress is
low. 相似文献
100.
S Fukuyama Y Hirasawa Y Kato M Nishio M Ohno S Nishino K Maeda M Kato Y Kita 《Canadian Metallurgical Quarterly》1997,282(1):236-242
(+/-)-(E)-4-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409) shows both potent in vitro vasorelaxant and antiplatelet activities via nitric oxide (NO) generated spontaneously from the compound. In this study, we measured spontaneous NO-releasing rates of a series of FK409 derivatives, of which chain lengths or substituents were systematically modified, in sodium-phosphate buffer solution at pH 7.4. Furthermore, we studied their in vitro antiplatelet and vasorelaxant effects to evaluate relationships between spontaneous NO-releasing activities of FK409 analogs and their biological activities. FK409 derivatives were found to possess different spontaneous NO-releasing rates and biological activities according to their structural modification. In addition, these studies revealed a close correlation between NO-releasing rates of FK409 derivatives and their in vitro antiplatelet activities in human platelet-rich plasma, whereas the in vitro vasorelaxant activities of these compounds in isolated rat aorta did not correlate with the rates of NO liberation. The vasorelaxant effects were supposed to be affected by the structural properties of FK409 derivatives as well as their NO-releasing abilities. 相似文献