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101.
PURPOSE: To evaluate the usefulness of T2-weighted fast spin-echo magnetic resonance (MR) imaging with a 512 x 256 matrix for assessment of the preoperative stage of endometrial carcinoma. MATERIALS AND METHODS: Twenty-eight women with histopathologically proved endometrial carcinoma underwent preoperative T2-weighted fast spin-echo, dynamic T1-weighted fast spin-echo, and postcontrast T1-weighted spin-echo MR imaging with a phased-array surface coil. The uterine long-axis planes in each sequence were reviewed at separate sessions by three radiologists blinded to the histopathologic data. RESULTS: For the diagnosis of myometrial invasion, no statistically significant differences were found among T2-weighted imaging, dynamic imaging, and postcontrast T1-weighted imaging. For the diagnosis of deep myometrial invasion, T2-weighted and dynamic images showed higher specificity than postcontrast T1-weighted images (T2-weighted, 89%; dynamic, 88%; and postcontrast T1-weighted, 80%). For cervical invasion, T2-weighted and dynamic images showed larger areas under receiver operating characteristic curves than did postcontrast T1-weighted images (T2-weighted, 0.78; dynamic, 0.71; and postcontrast T1-weighted, 0.67). CONCLUSION: T2-weighted imaging is useful for identifying the stage of endometrial carcinoma.  相似文献   
102.
103.
We cloned cDNAs encoding mouse homologues for the human DNA helicase Q1/RecQL (human helicase Q1) which has homology with the Escherichia coli RecQ protein and found that they encode two isoforms. The two isoforms are identical over the entire sequence except for the carboxyl terminal sequence spanning less than 30 amino acids. One of the two isoforms, alpha, contains a sequence, KKRK, in the carboxyl terminus, which is also contained in human helicase Q1 and was confirmed to function as the nuclear localization signal. The other form, beta, does not contain such a sequence. Expression of mouse helicase Q1 mRNA is extremely and relatively high in the testis and the thymus, respectively. RT-PCR analysis revealed that helicase Q1alpha was expressed in all tissues tested and the beta form was expressed only in the testis. A survey of expression of Q1alpha and Q1beta mRNA in the testis after birth revealed that Q1alpha mRNA is expressed in all testes of mice aged from 7 days to 8 weeks, and the expression of Q1beta mRNA begins 14 days after birth, corresponding to the appearance of cells in the pachytene stage.  相似文献   
104.
Pb(Zr,Ti)O3 (PZT) thick films were deposited onto stainless-steel substrates by aerosol deposition using different kinds of carrier gases and were irradiated by CO2 laser both during and after deposition, for the recovery of ferroelectricity. The ferroelectric and dielectric properties of PZT films deposited using oxygen and nitrogen gases and irradiated by CO2 laser were superior to those of films deposited using He gas and irradiated by the laser. Some kinds of defects within the film were relaxed by CO2 laser irradiation during deposition, and grain growth in the film was promoted by post-annealing using laser irradiation.  相似文献   
105.
Development of neural circuits generating fetal oral-motor activity was characterized in an in vitro isolated brainstem block preparation. Rhythmical trigeminal activity (RTA) at E20-E21 resembled either the pattern or rhythm of neonatal RTA. Conversely, at E18-E19, RTA displayed a different pattern of discharge from neonatal RTA, and output was not regular but intermittent with another slow rhythm.  相似文献   
106.
107.
Charged ultrafiltration membranes were prepared by photografting sodium styrene sulfonate onto photosensitive polyacrylonitrile membrane containing bromine atoms. The degree of the photografting was characterized by contact angles of air or n-octane in water and FTIR spectra for the negatively charged membrane. Permeations of dextran and dextransulfate through the negatively charged membranes were studied by ultrafiltration in the aqueous solutions of both solutes. With an increase of photoirradiation, the permeability of the solutes decreased. Also, an electrostatic repulsion of the solute and the membrane was confirmed by direct comparison between the permeability of the solutes, dextran, and dextransulfate, each having similar molecular size.  相似文献   
108.
Submerged membrane bioreactors (MBRs) have been gaining in popularity in various types of wastewater treatment. One drawback of submerged MBRs is difficulty in removing nitrogen as they are accompanied with intensive aeration inside the reactor and therefore principally operated under aerobic conditions. In order to address this problem, a simple modification for submerged MBRs, insertion of baffles to create alternative aerobic/anoxic conditions, was proposed. In this study, the performance of the proposed baffled membrane bioreactor (BMBR) was investigated based on a pilot-scale experiment using a real municipal wastewater. With appropriate operating conditions, the BMBR could remove more than 70% of total nitrogen contained in the feed water without any external carbon source. The BMBR demonstrated a good treatment performance in terms of TOC and phosphorus removal as well. Increase of trans-membrane pressure difference was subtle, which might be attributed to the alternative creation of aerobic/anoxic conditions.  相似文献   
109.
Experiments were carried out to investigate the flow pattern, average void fraction, and pressure drop of an upward air‐water two‐phase flow in vertical tubes of 25‐mm inside diameter with wire coils of varying wire diameter, pitch, and number of coils in cross section. Five kinds of flow patterns—bubble, slug, churn, semiannular, and annular flow—were defined based on the observation of flow behavior in the experiments. At higher water flowrates, the bubble‐to‐slug transition occurred at lower air flowrates in tubes with wire coils than in smooth tubes. The average void fraction was found by using the drift flux model. Further, the experimental results of the friction pressure drop were compared with the Lockhart‐Martinelli correlation. As a result, a correlation with the constant C in Chisholm's equation was obtained as a function of the wire coil pitch‐to‐diameter ratio. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(8): 639–651, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10066  相似文献   
110.
BACKGROUND: The increase in the incidence of iatrogenic injury to the extrahepatic biliary tree that has been documented since the introduction of laparoscopic cholecystectomy (LC) has been explained as a 'learning curve' problem. The early New Zealand experience has been published and the present study was undertaken to determine whether there had been any change in the incidence, nature and management of laparoscopic biliary injuries (LBI) after further experience with LC. METHODS: A nationwide audit was undertaken in 1995 by two confidential postal questionnaires: to all active general surgeons (n=184, response rate 60%), and to all endoscopists performing endoscopic retrograde cholangiopancreatography (ERCP) (n=18, response rate 100%). RESULTS: The total number of LBI was 21, compared with 41 for 1991-92. The site and nature of the injuries were similar for the two survey periods. More of the injuries appeared to be diagnosed after the operation and prior to discharge (25% vs 47%). Calculating the national incidence of LBI was not possible without complete reporting, but in the subset of surgeons responsible for the LBI there was no apparent decrease in the incidence of all LBI (2.8% vs 2.9%), those requiring active re-intervention (2.4% vs 2.7%) and major duct injury (1.1% vs 0.7%), despite a significant increase in the surgeons' prior experience with LC (20% vs 61% of surgeons had performed more than 100 LC). There were some concerning trends in management: a less frequent use of ERCP in patients with LBI diagnosed after surgery (76% vs 65%) and a higher proportion of patients with minor injuries managed by re-operation (26% vs 50%). CONCLUSIONS: The present study indicates that iatrogenic biliary injury is a persistent problem in New Zealand, despite increasing experience with LC, and suggests the need for more intensive scrutiny of operative technique and training. There is scope to manage more patients with minor duct injuries conservatively.  相似文献   
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