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991.
992.
OBJECTIVE: To investigate trends in the incidence of giant cell arteritis over a 42-year period in Olmsted County, Minnesota. DESIGN: Population-based incidence study. SETTING: Olmsted County, Minnesota. METHODS: All incidence cases of giant cell arteritis first diagnosed between 1950 and 1991 were identified using the unified record system at Mayo Clinic. Age- and sex-specific incidence rates were calculated using the number of incidence cases as the numerator and population estimates as the denominator. Overall rates were age- and sex-adjusted to the 1980 United States white population. The annual incidence rates were graphically illustrated using a 3-year centered moving average. RESULTS: Between 1950 and 1991, 125 Olmsted County residents (103 women and 22 men) were diagnosed with giant cell arteritis. The age- and sex-adjusted incidence per 100,000 persons 50 years of age or older was 17.8 (95% CI, 14.7 to 21.0); incidence was significantly higher in women (24.2 [CI, 19.5 to 28.9]) than in men (8.2 [CI, 4.8 to 11.6]). Age-specific incidence rates increased with age (P < 0.0001). The annual incidence rates increased significantly over the study period (P = 0.002) and appear to have clustered in five peak periods, which occurred about every 7 years. A significant calendar-time effect was identified; it predicted an increase in incidence of 2.6% (CI, 0.9% to 4.3%) every 5 years. CONCLUSIONS: Our observation of a regular cyclic pattern in incidence rates over time supports the hypothesis of an infectious cause for giant cell arteritis. Similar studies in other populations are needed to confirm our findings. 相似文献
993.
The synthesis of diamond has been accomplished from carbon disulfide (CS2 ) in hydrogen (H2 ) using tungsten hot filament chemical vapor deposition. A continuous layer was deposited on silicon and characterized using Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy. The polycrystalline film exhibited a sharp Raman peak at 1331.4 cm−1 and a broad low–intensity peak at approximately 1500 cm−1 . X–ray diffraction analysis showed peaks corresponding to the {111}, {220}, and {311} reflections of diamond with evidence of (110) texture. Diamond growth from CS2 in H2 was observed to be highly faceted by scanning electron microscopy. 相似文献
994.
Crits-Christoph Paul; Gibbons Mary Beth Connolly; Barber Jacques P.; Gallop Robert; Beck Aaron T.; Mercer Delinda; Tu Xin; Thase Michael E.; Weiss Roger D.; Frank Arlene 《Canadian Metallurgical Quarterly》2003,71(5):918
This study examined endorsement of 12-step philosophy and engagement in recommended 12-step activities as a mediator of the outcomes of individual plus group counseling for cocaine dependence. Assessments of drug use outcomes and the mediator were made at baseline and monthly for 6 months. Engagement in recommended 12-step activities was found to be a partial statistical mediator of drug use outcomes of individual (plus group) drug counseling, but no evidence for change in the mediator preceding change in drug use was found. In addition, a measure of beliefs about addiction developed to test mediation of outcome of cognitive therapy was found to correlate moderately with drug use outcomes in both cognitive therapy and individual drug counseling. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
A model for gender schema configuration and functioning is presented. Two experiments were designed to assess the usual automatic functioning of gender stereotyped information and the possibility of masking gender stereotypes by adding relevant information (Experiment 1), and to show the complex structure of gender schema configuration and updating (Experiment 2). In Experiment 1, several stereotyped scenarios were presented to 11-year-olds. The results confirmed the possible inhibition of gender stereotyped information. In Experiment 2, two hypothetical gender-stereotyped situations were presented to 480 22-50-yr-olds who answered questions about the assigned sex (man or woman) and the main assigned psychological traits (masculine or feminine) of a virtual person. The results supported the model. Some conclusions and further research are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
JS Sullivan CL Morris HM McClure E Strobert BB Richardson GG Galland IF Goldman WE Collins 《Canadian Metallurgical Quarterly》1996,55(3):344-349
The development and testing of vaccines directed against Plasmodium vivax has relied on Saimiri and Aotus monkeys as the animal test system and on chimpanzees to provide infective gametocytes to produce sporozoites for monkey challenge studies and vaccine development. One sporozoite-induced and 29 blood-induced infections with the Salvador I strain of P. vivax were studied in splenectomized chimpanzees. Eighteen primary infections with P. vivax resulted in maximum parasite counts ranging from 1,519 to 81,810/ microliters (median 29,100/microliters). Twelve infections induced in animals previously infected with the homologous or heterologous strains of P. vivax had maximum parasite counts ranging from 155 to 14,136/microliters (median 1,736/microliters). A total of 202 of 237 lots containing a total of 293,175 Anopheles freeborni, An. stephensi, An. gambiae, An. dirus, An. quadrimaculatus, and An. maculatus mosquitoes were infected by membrane feeding on gametocytes from chimpanzees. Despite lower levels of parasitemia during secondary (reinfection) parasitemia, 66 of 70 lots of mosquitoes (94.3%) were infected. Based on the mean number of oocysts per positive mosquito gut, An. freeborni was more heavily infected than An. stephensi; An. stephensi was more heavily infected than An. gambiae; there was no significant difference between An. stephensi and An. dirus. Sporozoites from An. stephensi, An. gambiae, An. dirus, and An. freeborni infected with the Salvador I strain of P. vivax produced in chimpanzees were used to infect 193 Saimiri and six Aotus monkeys as well as one chimpanzee. 相似文献
997.
Immunogenicity and tolerability of a new formalin-inactivated, alum-adjuvanted whole virus vaccine against hepatitis A (VAQTA, MSD, West Point, USA) were evaluated by immunizing 52 healthy, anti-HAV negative volunteers with a 1 ml dose. A booster dose was given 6 months later. In these young adult vaccinees [27 males and 25 females, 19-34 (mean 26) years of age] VAQTA proved to be well tolerated and highly immunogenic. Two weeks after administration of one vaccine dose, all but one of the recipients (98%) had anti-HAV concentrations above the presumed minimum protective level of 10 IU l-1 with a geometric mean concentration (GMC) of 165 IU l-1. After 4 weeks, a 100% seroconversion rate could be demonstrated with a fourfold increase of the GMC to 728 IU l-1. Six months after vaccination, all but one of the 50 volunteers coming back for booster (98%) showed anti-HAV levels within the protective range. The antibody concentrations had decreased in the majority of vaccinees to a GMC of 362 IU l-1. The booster dose given at that time was shown to be very effective, leading to a pronounced rise of anti-HAV levels in all recipients with a 17-fold increase of the GMC to 6040 IU l-1. Six months after the booster, all vaccinees were still seropositive with a GMC of 3444 IU l-1. Higher antibody levels were found in females, the difference being significant 4 weeks and 6 months after vaccination and 4 weeks after booster. No serious local or systemic adverse reactions were observed. 相似文献
998.
VV Dmitriev GG Arabidze ON Epifanova AN Rogoza TV Metelitsa VB Mychka 《Canadian Metallurgical Quarterly》1996,68(9):35-37
24-hour monitoring of arterial pressure has been performed outpatiently in 20 subjects with mild or moderate essential hypertension using portable system Space Labs 90207. The design of the study implied 2 weeks of observation without any treatment followed by a 4-week course of lomir SRO-5 plus a 2-week course of lomir administration in a double dose. Control examination was performed at the end of each period. It was established that a 4-week lomir course results in a lowering of systolic and diastolic pressure by 8.4 + -2.1 and 6.9 + -1.3 mm Hg, respectively. Double-dose lomir was also effective: a fall in both systolic and diastolic pressure by 15.6 + -3.2 and 8.1 + -1.8 mm Hg, respectively, was achieved. 相似文献
999.
1000.
1. Depolarization of mesangial cells has been shown to occur following an outward movement of chloride ions from the cell. We have shown previously that mesangial cells from the H-2Kb-tsA58 transgenic mouse possess a significant whole-cell chloride conductance and consequently are a suitable preparation for the study of potential chloride channel inhibitors. 2. The effects on the whole-cell chloride conductance of the chloride channel inhibitor, 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB) and the potassium channel openers, (KCOs) P1075 and pinacidil were investigated in mesangial cells from the H-2Kb-tsA58 transgenic mouse cultured in permissive conditions (at 33 degrees C in the presence of 50 u ml-1 murine gamma-interferon). 3. In symmetrical solutions of 140 mM tetramethylammonium chloride (TMAC1) the whole-cell chloride conductance was 1.08 +/- 0.05 nS (n = 63) and this could be reversibly inhibited by 5 x 10(-5) M NPPB. 4. Both P1075 and pinacidil inhibited the whole-cell chloride conductance. This inhibition was not reversible after drug washout and was demonstrated only when drugs were applied to the extracellular surface of the cells. Very low concentrations of the drugs were found to reduce the chloride conductance after 16 h incubation but under no circumstances studied was the conductance totally inhibited, leaving a mean residual current of 0.33 +/- 0.03 nS (n = 12). 5. The effects of different peptide calcium concentrations on the magnitude of the residual current in the presence of the drugs were investigated. The residual current was reduced with 10(-8) M calcium in the pipette and increased with 10(-3) M pipette calcium. Therefore, these data suggest that P1075 and pinacidil selectively inhibit a calcium-independent chloride conductance in mesangial cells from the H-2Kb-tsA58 transgenic mouse. 相似文献