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951.
HP Selker JR Beshansky JL Griffith TP Aufderheide DS Ballin SA Bernard SG Crespo JA Feldman SS Fish WB Gibler DA Kiez RA McNutt AW Moulton JP Ornato PJ Podrid JH Pope DN Salem MR Sayre RH Woolard 《Canadian Metallurgical Quarterly》1998,129(11):845-855
BACKGROUND: Approximately 6 million U.S. patients present to emergency departments annually with symptoms suggesting acute cardiac ischemia. Triage decisions for these patients are important but remain difficult. OBJECTIVE: To test whether computerized prediction of the probability of acute ischemia, used with electrocardiography, improves the accuracy of triage decisions. DESIGN: Controlled clinical trial. SETTING: 10 hospital emergency departments in the midwestern, southeastern, and northeastern United States. PATIENTS: 10689 patients with chest pain or other symptoms suggestive of acute cardiac ischemia. INTERVENTION: The probability of acute ischemia predicted by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), either automatically printed or not printed on patients' electrocardiograms. MEASUREMENTS: Emergency department triage to a coronary care unit (CCU), telemetry unit, ward, or home. Other measurements were the bed capacity of the CCU relative to that of the telemetry unit; training or supervision status of the triaging physician; and patient diagnoses and outcomes based on clinical, electrocardiographic, and creatine kinase data. RESULTS: For patients without cardiac ischemia, in hospitals with high-capacity CCUs and relatively low-capacity cardiac telemetry units, use of ACI-TIPI was associated with a reduction in CCU admissions from 15% to 12%, a change of -16% (95% CI, -30% to 0%), and an increase in emergency department discharges to home from 49% to 52%, a change of 6% (CI, 0% to 14%; overall P=0.09). Across all hospitals, for patients evaluated by unsupervised residents, use of ACI-TIPI was associated with a reduction in CCU admissions from 14% to 10%, a change of -32% (CI, -55% to 3%); a reduction in telemetry unit admissions from 39% to 31%, a change of -20% (CI, -34% to -2%); and an increase in discharges to home from 45% to 56%, a change of 25% (CI, 8% to 45%; overall P=0.008). Among patients with stable angina, in hospitals with high-capacity CCUs, use of ACI-TIPI was associated with a reduction in CCU admissions from 26% to 13%, a change of -50% (CI, -70% to -17%), and an increase in discharges to home from 20% to 22%, a change of 10% (CI, -29% to 71%; overall P=0.02). At hospitals with high-capacity telemetry units, use of ACI-TIPI was associated with a reduction in telemetry unit admissions from 68% to 59%, a change of -14% (CI, -27% to 1%), and an increase in emergency department discharges to home from 10% to 21%, a change of 100% (CI, 22% to 230%; overall P=0.02). Among patients with acute myocardial infarction or unstable angina, use of ACI-TIPI did not change appropriate admission (96%) to the CCU or telemetry unit at hospitals with high-capacity CCUs or telemetry units. CONCLUSIONS: Use of ACI-TIPI was associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. This result varied as expected according to the CCU and cardiac telemetry unit capacities and physician supervision at individual hospitals. Appropriate admission for unstable angina or acute infarction was not affected. If ACI-TIPI is used widely in the United States, its potential incremental impact may be more than 200000 fewer unnecessary hospitalizations and more than 100000 fewer unnecessary CCU admissions. 相似文献
952.
OBJECTIVE: To assess how surgery affected the quality of life of patients with acoustic neuromas and to investigate possible predictors of the functional outcome following surgery. STUDY DESIGN: A questionnaire based on the Glasgow Benefit Inventory was completed by patients randomly selected following acoustic neuroma surgery. SETTING: Skull base surgery unit of a university teaching hospital (tertiary referral center). PATIENTS: Fifty-three patients with acoustic tumors (follow-up, 1 to 3 y). RESULTS: With regard to overall quality of life, nine patients (17.4%) reported that it became better, 28 patients (53.8%) worse, and 15 patients (28.8%) that it remained the same. Four patients (7.8%) became better off financially, 15 patients (29.4%) worse, and 32 (62.8%) remained unchanged. Forty-one patients (78.8%) did not change their occupation, and 11 (21.2%) had to change their occupation, mainly because of the adverse effects of the operation. With regard to the age at operation, older patients were found to have better overall quality of life. Moreover, younger patients had worse postoperative financial status and they were more likely to change their occupation after the operation. The tumor size did not significantly affect the overall postoperative quality, but it did affect the postoperative financial status (patients with larger tumors were more likely to have worse postoperative financial status). CONCLUSION: Acoustic neuroma surgery has a significant impact on patients' overall quality of life. Surgeons proposing to operate on small tumors should not assume that the impact on patients' life will be necessarily less than that following the removal of larger tumors. All patients, especially in the younger age group, should be prepared and thoroughly informed about the consequences of the operation on their quality of life. 相似文献
953.
HC Schober ZH Han AJ Foldes MS Shih DS Rao R Balena AM Parfitt 《Canadian Metallurgical Quarterly》1998,9(7):1225-1233
To characterize the magnitude and location of mineralized bone loss, 40 patients (20 men, 20 women, 29 white, 11 black) with clinically significant renal osteodystrophy who could be unambiguously classified based on histologic criteria as having osteitis fibrosa (OF; 20 cases) or osteomalacia (OM; 20 cases) were studied; they had been on maintenance hemodialysis for 4.6 +/- 3.0 yr. One hundred forty-two healthy women of similar age and ethnic composition served as control subjects. In all subjects, the proportions of mineralized bone, osteoid, and porosity (nonbone soft tissue) were measured separately in cortical and cancellous bone tissue, from intact full-thickness biopsies of the ilium, representative of the axial skeleton. The results were related to the volumes of cortical and cancellous bone tissue separately and to the volume of the entire biopsy core. Approximately three-quarters of the patients had measurements in the appendicular skeleton by single photon absorptiometry of the radius and morphometry of the metacarpal. Disease effects did not differ significantly between ethnic groups. Mineralized cortical bone volume (per unit of core volume) was reduced by approximately 45% in both patient groups. Mineralized cancellous bone volume was significantly increased by 36% in the patients with OF and nonsignificantly reduced by 9% in the patients with OM; however, the reduction in the latter patients was significant in relation to tissue volume. The combined total deficit for both types of iliac bone was approximately 20% in the patients with OF and approximately 40% in the patients with OM. Significant reductions in appendicular cortical bone were demonstrated in both patient groups at both measurement sites. Regardless of the current histologic classification, the major structural abnormality in the skeleton is generalized thinning of cortical bone due to increased net endocortical resorption, the most characteristic effect on bone of hyperparathyroidism. Protection of the skeleton from the adverse consequences of renal failure will require therapeutic intervention in patients with no symptoms of either renal or bone disease. 相似文献
954.
TP Le LW Church G Corradin RL Hunter Y Charoenvit R Wang P de la Vega J Sacci WR Ballou N Kolodny S Kitov GM Glenn RL Richards CR Alving SL Hoffman 《Canadian Metallurgical Quarterly》1998,16(2-3):305-312
Only low antibody levels were obtained from vaccinating human volunteers with single-chain peptide from the Plasmodium falciparum circumsporozoite protein (PfCSP). This resulted in modest protection against sporozoite challenge. In addition, HLA restriction limits the probability of synthesis of a vaccine effective for a diverse population. We report immunization studies with a multiple antigen peptide (MAP) system consisting of multiple copies of a B-cell epitope from the central repeat region of the PfCSP in combination with a universal T-cell epitope, the P2P30 portion of tetanus toxin. This MAP4(NANP)6P2P30 vaccine was highly immunogenic in four different strains of mice when used with various safe and nontoxic adjuvants. When this MAP vaccine was encapsulated in liposomes with lipid A and adsorbed to aluminium hydroxide and given three times at 4-week intervals, the resultant antibody prevented 100% of sporozoites from invading and developing into liver stage infection. This high degree of immunogenicity of MAP4(NANP)6P2P30 vaccine formulated in liposomes, lipid A and aluminum hydroxide provides the foundation for consideration of human trials with this formulation. 相似文献
955.
The method of angular line (MAL) is presented for calculating the resonant frequency of microstrip antenna, which is available in other literature and originally used to analyze various waveguide structure. The results obtained by using this method are in conformity with those reported elsewhere. 相似文献
956.
Flavocytochrome b2 or L-lactate dehydrogenase from yeasts catalyzes the oxidation of L-lactate at the expense of monoelectronic acceptors such as cytochrome c, its physiological partner. When incubated in the presence of both L-lactate and a keto acid, the enzyme catalyzes a transhydrogenation reaction wherein only the flavin is involved. During this reaction, the substrate alpha-hydrogen is transferred not only to the solvent but also in part to the keto acid, which acts as reverse substrate. Thus, when bound to the reduced enzyme, this hydrogen is sticky. In the context of a carbanion mechanism, it resides on Nepsilon of His373, the active site base. We have shown before that a correlation between the amount of intermolecular hydrogen transfer from [2-3H] lactate and the keto acid reverse substrate concentration enables the determination of the first-order rate constant, kHe, for exchange of the substrate-derived protein-bound hydrogen with bulk solvent (Urban P, Lederer F, 1985, J Biol Chem 260:11115-11122). In this work, we show that the exchange with the solvent appears to be independent of the phosphate buffer concentration in the range from 40 to 500 mM. It is thus probable that exchange occurs directly with water molecules. The second-order rate constant for exchange is then 0.16 (+/-0.03) M(-1) s(-1). Using the Eigen equation, this figure yields a pKa of 9.1+/-0.1 for His373 in the reduced enzyme, compared to a probable value of 6.0 or less in the oxidized enzyme (Suzuki H, Ogura YC, 1970, J Biochem 67:291-295). The mechanistic significance of these results is discussed. 相似文献
957.
In this note, we consider a vertical cable which is pinched at the upper end. A mass is attached at the lower end where a control force is also applied. We show that this hybrid system is uniformly stabilized by choosing a suitable control law for the control force depending on the velocity and angular velocity at the free end. Moreover for specific values of the feedback coefficients, we obtain the rate of decay of the energy of the system 相似文献
958.
Summary
Demineralized xenogeneic bone (DXB) was prepared from bovine cortical tibia and graft copolymerized with glycidylmethacrylate
(GMA) using a combination of potassium persulfate (K2S208) and sodium metabisulfite (Na2S2O5)as redox initiating system in aqueous medium. To optimize the reaction condition, the concentrations of backbone, monomer,
initiator, temperature and time were varied. The percent grafting was found to increase initially and thereafter decrease
in most of the cases. The optimum temperature and time were found to be 40°C and 180 minutes, respectively. The grafting results
have been discussed and a reaction mechanism is proposed. Functional groups and structural changes of the graft copolymer
were determined by Fourier transform infrared (FT-IR) spectroscopic method for proof of grafting and the results are discussed.
Received: 12 August 2002/Revised version: 30 October 2002/ Accepted: 25 November 2002
Correspondence to R. Murugan 相似文献
959.
B. Narsimlu B. Venkateswara Rao P. K. Mishra K. V. Rao 《Canadian Metallurgical Quarterly》2004,130(2):154-159
The effect of stone and vegetative covers was evaluated for soil and water conservation in a waterway on alfisols. Experiments were conducted on a hydraulic tilting flume under simulated flow (93 and 40 cm2?s?1) and slope (0.1, 1.0, 3.0, and 5.0%) conditions. The depth of soil was maintained at 0.35 m over a perforated bed to facilitate deep drainage. A comparative study of bare soil, stone cover (50%), and vegetative cover (50%) is made to evaluate soil loss, deep drainage, Manning’s roughness coefficient, and the Froude number. The study has revealed that stone cover is more effective than vegetative cover at lower discharge in reducing the flow velocity, and thereby soil erosion. Deep drainage has been reduced from lower to higher discharge for all the slopes with cover measures, including bare soil. It is found that cover measures are necessary beyond 3% slope in order to prevent rill erosion in alfisols. 相似文献
960.
Padmaja R. Jonnalagadda Pratima Rao Ramesh V. Bhat & A. Nadamuni Naidu 《International Journal of Food Science & Technology》2004,39(2):125-131
The type and extent of colours added to ready‐to‐eat (RTE) foods prepared in the non‐industrial sector of India was investigated. Of the 545 RTE foods analysed, 90% contained permitted colours, 2% contained a combination of permitted and non‐permitted colours and 8% contained only non‐permitted colours. However in RTE foods with permitted colours, 73% exceeded 100 ppm, as prescribed by the Prevention of Food Adulteration Act of India, and 27% were within the prescribed levels. Among the permitted colours, tartrazine was the most widely used colour followed by sunset yellow. The maximum concentration of colours was detected in sweet meats (18 767 ppm), non‐alcoholic beverages (9450 ppm), miscellaneous foods (6106 ppm) and hard‐boiled sugar confectioneries (3811 ppm). Among the non‐permitted colours found, rhodamine was most commonly used. Some of the foods, such as savouries and miscellaneous foods like sugar coated aniseed and almond milk, are not supposed to contain colours as per the Prevention of Food Adulteration Act, but were found to contain colours. 相似文献