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71.
This paper is one of three in a series prepared by the Research, Science and Therapy Committee of The American Academy of Periodontology and is intended for the information of the dental profession. It represents the position of the Academy regarding the current state of knowledge about treatment of gingivitis and periodontitis. The other papers are entitled The Etiology and Pathogenesis of Periodontal Diseases and Diagnosis of Periodontal Diseases.  相似文献   
72.
This study examined the role of maternal social behavior in children's behavioral reactions to provocation. Popular and rejected 1st graders and their mothers independently completed an intention-cue detection task. Mothers also completed a questionnaire assessing if their responses to their child were based on the child's intent. A moderate relation within the mother–child dyad was noted for all measures. Rejected children and their mothers reported more aggressive behavioral responses to nonhostile and ambiguous provocations than did popular children and their mothers. Mothers of popular children provided more prosocial resolutions to provocation than did mothers of rejected children. In addition, mothers of popular children focused more on the intent of their children's actions than did mothers of rejected children, particularly when behavior led to negative outcomes. Implications of these findings in terms of the correlates of social status are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this study potential vaccine candidate immunogens were identified and evaluated in a vaccine challenge trial. Calves vaccinated with a partially purified fraction of Psoroptes ovis-soluble proteins had 8 of 14 calves free of palpable lesions 8 wk after a challenge infestation. A self-grooming behavioral response elicited by a pruritic immediate-type allergic reaction was believed to be an effector in protecting the vaccinated calves from a clinical P. ovis infestation.  相似文献   
75.
Lipoprotein lipase (LPL) hydrolyses triglycerides in chylomicrons and in very low density lipoproteins. In this study, a new sensitive enzyme immunoassay, the dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA), for the quantification of immunoreactive LPL mass in biological specimens was developed. In the indirect sandwich DELFIA assay polyclonal anti-human or anti-bovine LPL IgGs were used as capture antibodies, monoclonal antibody (mAb) 5D2 and Eu(3+)-labelled goat anti-mouse IgG were used as detection antibodies. In the direct sandwich DELFIA assay, mAb 5D2 was used as capture and Eu(3+)-labelled mAb 5D2 as detection antibodies. Both purified bovine and human LPL proteins served as standards in the indirect and the direct DELFIA assay. Standard curves were linear between 0.1 and 1000 ng LPL/ml, assuring the sensitivity of the DELFIAs within this range. Mean values for immunoreactive LPL mass in normal individuals were found to be 40.3 +/- 14.4 ng/ml preheparin plasma and 334.1 +/- 71 ng/ml postheparin plasma. In patients affected with type I hyperlipoproteinemia 82.4 +/- 29.3 ng/ml (postheparin plasma) were determined. Coefficients of inter- and intra-assay variation were 4.3% and 6.2% on average. The correlation coefficient between the indirect and the direct DELFIA technique was 0.9694. The correlation coefficient between immunoreactive LPL mass (estimated by DELFIA) and LPL activity (estimated by the LPL activity assay) was 0.9345. Our data are consistent with the concept that LPL is active as a dimer. Dissociation of the LPL dimer into monomers is tightly coupled to both loss of immunoreactivity and enzyme activity of LPL.  相似文献   
76.
OBJECT: Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated. METHODS: The authors examined the spinal cords of 15 patients who died between 3 hours and 2 months after a traumatic SCI. Apoptotic cells were found at the edges of the lesion epicenter and in the adjacent white matter, particularly in the ascending tracts, by using histological (cresyl violet, hematoxylin and eosin) and nuclear staining (Hoechst 33342). The presence of apoptotic cells was supported by staining with the terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labeling technique and confirmed by immunostaining for the processed form of caspase-3 (CPP-32), a member of the interleukin-1beta-converting enzyme/Caenorhabditis elegans D 3 (ICE/CED-3) family of proteases that plays an essential role in programmed cell death. Apoptosis in this series of human SCIs was a prominent pathological finding in 14 of the 15 spinal cords examined when compared with five uninjured control spinal cords. To determine the type of cells undergoing apoptosis, the authors immunostained specimens with a variety of antibodies, including glial fibrillary acidic protein, 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase), and CD45/68. Oligodendrocytes stained with CNPase and a number of apoptotic nuclei colocalized with positive staining for this antibody. CONCLUSIONS: These results support the hypothesis that apoptosis occurs in human SCIs and is accompanied by the activation of caspase-3 of the cysteine protease family. This mechanism of cell death contributes to the secondary injury processes seen after human SCI and may have important clinical implications for the further development of protease inhibitors to prevent programmed cell death.  相似文献   
77.
A 39-year-old woman presented with acute myocardial infarction due to spontaneous dissection of the left anterior descending artery. This was treated conservatively. She had been on combined oral contraceptive pills from the age of 22. Repeat coronary angiography 7 months later revealed spontaneous complete healing.  相似文献   
78.
The effect of Mycobacterium tuberculosis infection on the viability of healthy (control) human alveolar macrophages was evaluated by staining with ethidium homodimer and calcein to discriminate live from dead cells. Infection with M. tuberculosis H37Ra or H37Rv increased macrophage mortality at 6 days from the control level of 3.8% +/- 0.7% to 28.7% +/- 6.9% or 12.6% +/- 3.1%, respectively (P < 0.001 for comparisons of all conditions). A role for tumor necrosis factor alpha (TNF-alpha) in the M. tuberculosis-induced cytolysis of alveolar macrophages was demonstrated by increased cytotoxicity following the addition of exogenous TNF-alpha to the cultures and by enhancement of macrophage survival when M. tuberculosis-infected alveolar macrophages were treated with pentoxifylline or anti-TNF-alpha antibody. The cytolytic mechanism was determined to be apoptosis by the demonstration of a characteristic internucleosomal ladder of genomic DNA by agarose gel electrophoresis, by finding nuclear fragmentation and condensation by electron microscopy, and by in situ terminal transferase-mediated nick end labeling of fragmented DNA in alveolar macrophages infected with M. tuberculosis in vitro. The latter technique was employed to reveal extensive apoptosis within caseating granulomas from lung tissue samples from clinical tuberculosis cases. The induction of apoptosis in alveolar macrophages by M. tuberculosis may play a role in the macrophage-pathogen interaction of tuberculosis in vivo.  相似文献   
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STUDY OBJECTIVE: To evaluate a range of doses of intravenous (i.v.) dolasetron mesilate, in preventing postoperative nausea and vomiting (PONV). DESIGN: Double-blind, placebo-controlled, randomized, multicenter trial. SETTING: Ten hospitals and/or surgical centers. PATIENTS: 281 women undergoing gynecologic surgery with general anesthesia. INTERVENTIONS: Patients received one of four single, i.v. doses of dolasetron mesilate (12.5 mg, 25 mg, 50 mg, and 100 mg) or placebo administered following cessation of anesthesia. MEASUREMENTS AND MAIN RESULTS: Patients were monitored for 24 hours following study drug administration. The antiemetic efficacy of each dolasetron mesilate dose was evaluated by recording the number and timing of emetic episodes, and the effects on nausea were assessed by use of visual analog scales (VAS). Safety was assessed by adverse event reports, clinical laboratory tests, electrocardiographic (ECG) measurements, and monitoring vital signs. Complete responses (patients with no emetic episodes and no escape antiemetic medication requirements in 24 hours) were achieved by 54% in the 12.5-mg, 67% in the 25-mg, and 59% in both the 50-mg and 100-mg dolasetron mesilate dose groups, and by 43% in the placebo group. Nausea VAS assessments demonstrated that dolasetron-treated patients were significantly (p = 0.048) more likely to report no nausea (VAS score < 5 mm) than those in the placebo group. Adverse events reported generally were mild in intensity, and there were no clinically significant changes in laboratory tests, vital signs, or ECG parameters. CONCLUSIONS: Dolasetron was effective and well tolerated for the prevention of PONV in female patients undergoing gynecologic surgery with general anesthesia.  相似文献   
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