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991.
E Rey A Moynot P d'Athis JY Pello A Maurel MO Frydman C Buisson G Olive 《Canadian Metallurgical Quarterly》1996,46(5):492-495
Buflomedil (CAS 55837-25-7, Fonzylane) is a peripherally vasoactive drug which improves nutritional blood flow in ischaemic tissue of patients with peripheral vascular disease by the way of an increase of perfusion in the microcirculation. Ten hemodialysed patients with chronic renal failure treated with intravenous infusion of 400 mg of buflomedil during 4 h of dialysis were included in the first study. This study was carried out to determine the dialysis plasma clearance and the amount of drug dialysed during the first intravenous administration of buflomedil. The dialysis clearance calculated from the amount recovered in dialysate was (mean +/- SD) 25.4 +/- 25.6 ml/min. The drug recovery resulting from hemodialysis represented a small fraction of the dose (< or = 5%). A second study was carried out to determine the accumulation of buflomedil in chronic hemodialysed patient. The drug concentration were measured before and at the end (4 h) of the infusion of buflomedil in six other patients maintained on intermittent hemodialysis (3 per week) for 4 weeks. The average Cmin and Cmax were stable during the 12 successive dialyses (mean +/- SD intervals were between 0.36 +/- 0.53 and 0.66 +/- 0.79 microgram/ml for Cmin and between 5.15 +/- 2.19 and 7.37 +/- 1.76 micrograms/ml for Cmax), showing no trend of accumulation of buflomedil. These results agree with the pharmacokinetics of the drug which is mainly metabolised in the liver and has a low renal clearance. Dialysis is unable to modify significantly the plasma concentration of the drug in regularly dialysed patients. 相似文献
992.
CC Tsai LR Mo CY Chou SJ Han RC Lin JY Kuo KK Chang 《Canadian Metallurgical Quarterly》1997,44(15):770-773
BACKGROUND/AIMS: To evaluate the technical feasibility and sensitivity of percutaneous transluminal forceps biopsy of bile duct diseases. MATERIAL AND METHODS: Seventeen fluoroscopic-guided transluminal forceps biopsies were performed in 16 patients with obstructive jaundice. The technique was performed through an existing percutaneous transhepatic tract. Multiple specimens were obtained after passing the forceps biopsy into a long 9-French sheath and the specimens were fixed with formalin for histopathologic diagnosis. RESULTS: Adequate samples for histological diagnosis was obtained in 12 of 17 procedures (sensitivity, 71%). Pathologic reports included pancreatic head carcinoma n = 2, cholangiocarcinoma n = 3, hepatoma with intrahepatic-bile duct invasion n = 3, common bile duct tumors n = 3 and chronic inflammation n = 1. Minor complications such as pain was noted in three patients while transient hemobilia was seen in two patients. CONCLUSIONS: Percutaneous transhepatic transluminal forceps biopsy is a safe technique which is easy to perform. This can be done through an existing transhepatic biliary tract with a sensitivity rate of 71%. 相似文献
993.
A comparative study of stamping and hydroforming processes for an automobile fuel tank using FEM 总被引:1,自引:0,他引:1
Beom-Soo Kang Bo-Mi Son Jeong Kim 《International Journal of Machine Tools and Manufacture》2004,44(1):87-94
The use of sheet metal in the hydroforming process for hollow bodies is a new manufacturing technology for the automotive industry. In this paper, a comparison is made between the forming processes of sheet hydroforming and conventional stamping for production of an automobile fuel tank using a commercial explicit FEM code. A modeling methodology for correlation between stamping and hydroforming is proposed in order to obtain the optimal process parameters for producing a sound hydroformed fuel tank. The simulation model for a conventional stamping process is also verified by comparison with experiment. Finally, it is concluded that the hydroforming process can produce a fuel tank with a more uniform and sound thickness distribution than the stamping operation. 相似文献
994.
A Arefiev F Prat JY Chapelon J Tavakkoli D Cathignol 《Canadian Metallurgical Quarterly》1998,24(7):1033-1043
Minimally invasive methods for the treatment of cancers, such as high-intensity focused ultrasound (HIFU) and high-energy shock waves (SW), have been proposed recently. Their feasibility for treatment of human cancer needs to be confirmed. A simplified model of isolated perfused pig liver that is close to the human liver in vivo has been proposed. The objective was to study the feasibility of deep focused tissue ablation with HIFU and SW in large organs approaching the size of the human liver. The model was demonstrated to be physiologically valid during the first 2 h of anoxic perfusion with a composite saline solution; arterial and portal pressure, enzymes, urea levels and bile secretion remained stable. It can simulate the major effects of perfusion and physical phenomena that occur in vivo during treatment. Histological analysis revealed no major changes. Previous results obtained in vivo in animal models at a depth of 2-3 cm were successfully reproduced and deeper lesion arrays at 4, 6, 8 and 9 cm from the surface were produced using the same principles. The depth of 9 cm from the liver surface is consistent with an extracorporeal treatment of most of the liver segments in man. Other applications of the model are proposed, particularly for the study of the role of interferences such as ribs and intestinal gas, blood perfusion and respiratory movements. 相似文献
995.
BACKGROUND: Due to the expression of urease, Helicobacter pylori is able to establish itself in the human stomach under acidic conditions. A novel host defence mechanism was recently proposed, suggesting that the formation of salivary nitrite in symbiosis with facultative anaerobic bacteria in the oropharynx, is aimed at enhancing the antimicrobial activity of gastric juice. AIMS: To investigate whether the addition of nitrite in physiological concentrations influences the resistance of H pylori to acid. METHODS: H pylori cultured from fresh gastric Biopsy specimens was exposed for 30 minutes to normal saline and to HCl/KCl buffer (0.2M) at pH 2 with urea (5 mM) added. The influence of potassium nitrite (50-1000 mumol/l) on bacterial survival was determined. RESULTS: Addition of nitrite (1 mM) to acidic solutions (pH 2) resulted in complete kill of H pylori within 30 minutes exposure time whereas acid alone allowed the organism to survive (p < 0.001). The antimicrobial effect of nitrite at pH 2 against H pylori was dose dependent and complete kill of organisms occurred at concentrations > or = 500 mumol/l. CONCLUSION: Acidified nitrite has anti-bacterial activity against H pylori. This should prompt further research into the effect of salivary nitrite on the survival of H pylori in the human stomach. 相似文献
996.
997.
Mun Hag Lee Sung Bin Kim Se Mo Son Jae Kee Cheon 《Korean Journal of Chemical Engineering》2006,23(2):309-316
In this paper, both mono-type: 4-hydroxycyclohexyl-4-vinylbenzenesulfonate(CHDv-m), 4-(4-hydroxycyclo-hexyl) cyclohexyl-4-vinylbenzenesulfonate(BCDv-m),
4-(2-(4-hydroxycyclohexyl)propan-2-yl)-cyclohexyl-4-vinyl-benzenesulfonate(IPDHv-m), 4-hydroxycyclohexyl-4-methylbenzenesulfonate(CHDp-m),
4-(4-hydroxycyclohexyl)-cyclo-hexyl-4-methylbenzenesulfonate(BCDp-m) and 4-(2-(4-hydroxycyclohexyl)propan-2-yl)-cyclohexyl-4-methylbenzene-sulfonate(IPDHp-m)
and di-type: 4,4’-di(vinylbenzenesulfonatyl)-cyclohexane(CHDv-d), 4,4’-di(vinylbenzenesulfonatyl)-1,1’-bicyclohexane(BCDv-d),
4,4 ’-di(vinlylbenzenesulfonatyl)-isopropylidene-dicyclohexane(IPDHv-d), 1,4-ditosyloxy cyclohexane(CHDp-d), 4,4’-ditosyloxy-1,1’
-bicyclohexane(BCDp-d) and 4,4’-ditosyloxy isopropylidene dicyclohexane (IPDHp-d) acid amplifiers were synthesized. Their
properties were characterized by1HNMR and DSC measurements. UV curing properties of samples prepared by using novel acid amplifiers were examined by measuring
the change of current according to UV radiation time and intensity. Also, the application of acid amplifiers to UV inks was
suggested. It was found that UV vehicles and inks with acid amplifier of 4–4’di(vinylbenzenesulfonatyl)-cyclohexane(CHDv-d)
had a more rapid degree of curing than other samples. 相似文献
998.
Platelet function was assessed before and one week after acute alcohol withdrawal in eighteen male alcoholics. Compared to normal male controls, the platelets of the alcoholics were slightly hypoaggregable on admission but became hyperaggregable one week after commencement of alcohol withdrawal therapy. The changes were most noticeable in those patients who were alcoholaemic on admission and when using ADP or adrenaline as aggregating agents. There was no consistent change in platelet counts or in platelet adenine nucleotide levels, both of which were normal. 相似文献
999.
In this paper, we present a new flicker evaluation model through the electrical simulation of the optical flicker phenomena in different kinds of poly-Si TFT-LCD arrays for the development and manufacturing of large-area and high-quality TFT-LCDs. We applied our flicker evaluation model to three different types of TFTs; excimer laser annealed (ELA) poly-Si TFT, silicide mediated crystallization (SMC) poly-Si TFT, and counter-doped lateral body terminal (LBT) poly-Si TFT. We compared the flicker quantitatively for these three different TFT-LCDs on 40 in. UXGA scale. We identified three major factors causing the flicker such as charging time, kickback voltage and leakage current, analyzed their relative contributions to the flicker, and evaluated the values of the flicker in decibel (dB) for the three different TFT-LCD arrays. In addition, we show that the flicker is very sensitive to the low-level (minimum) gate voltage due to the large leakage current of the poly-Si TFT, and the low-level gate voltage should be chosen carefully to minimize the flicker. 相似文献
1000.
DK Zhen JY Wang VM Falco W Weber L Delli-Bovi DW Bianchi 《Canadian Metallurgical Quarterly》1998,18(11):1181-1185
Prenatal diagnosis of fetal chromosomal abnormalities using interphase fetal nucleated erythrocytes (FNRBCs) separated from maternal peripheral blood can be technically challenging due to the limited number of FNRBCs available for analysis, the limited number of probes that can be used simultaneously, and low FISH efficiency on the formaldehyde-fixed and immunohistochemically stained interphase FNRBCs. We developed a technique of sequential FISH analysis that involves removal of the previous hybridized probe under denaturing conditions, and rehybridization with different probes to improve FISH efficiency. This technique facilitates the analysis of multiple chromosome-specific probes on the same nuclei. Results from our experiments show that FISH can be performed at least nine times on the same interphase nucleus and at least three different probes can be used simultaneously. Thus, theoretically, at least 24 different chromosomes can be analysed on a single interphase fetal cell isolated from maternal blood. We have termed this technique 'Poly-FISH', and have successfully diagnosed trisomy 21, triploidy, and other chromosome abnormalities in FNRBCs using this technique. 相似文献