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991.
Current National Committee for Clinical Laboratory Standards (NCCLS) susceptibility guidelines for quality control testing with Haemophilus influenzae do not include a beta-lactamase-producing strain that could detect the deterioration of the beta-lactamase inhibitor components of amoxicillin-clavulanic acid, ampicillin-sulbactam, and piperacillin-tazobactam. The objective of the study was to determine if comparable quality control results for Escherichia coli ATCC 35218, a beta-lactamase-producing strain, would be produced for the three beta-lactam-beta-lactamase inhibitor agents with Haemophilus test medium and Mueller-Hinton medium. The criteria used in this study to determine if Haemophilus test medium was acceptable for quality control testing of E. coli ATCC 35218 was that 100% of the results obtained with an antimicrobial agent-methodology combination needed to be within the acceptable NCCLS ranges established with Mueller-Hinton medium. The MIC testing results obtained by the broth microdilution and E-test methods with amoxicillin-clavulanic acid and piperacillin-tazobactam were all within the NCCLS ranges; however, the results obtained with ampicillin-sulbactam by both methods were not within the NCCLS ranges. Acceptable results were obtained by the disk diffusion methodology with ampicillin-sulbactam and piperacillin-tazobactam but not with amoxicillin-clavulanic acid. When performing susceptibility testing with H. influenzae with the beta-lactam-beta-lactamase inhibitors, in addition to quality control testing with H. influenzae ATCC 49247, testing of E. coli ATCC 35218 on Haemophilus test medium is an effective way to monitor the beta-lactamase inhibitors in some antimicrobial agent-methodology combinations. 相似文献
992.
H Rosen R Hajdu L Silver H Kropp K Dorso J Kohler JG Sundelof J Huber GG Hammond JJ Jackson CJ Gill R Thompson BA Pelak JH Epstein-Toney G Lankas RR Wilkening KJ Wildonger TA Blizzard FP DiNinno RW Ratcliffe JV Heck JW Kozarich ML Hammond 《Canadian Metallurgical Quarterly》1999,283(5402):703-706
A carbapenem antibiotic, L-786,392, was designed so that the side chain that provides high-affinity binding to the penicillin-binding proteins responsible for bacterial resistance was also the structural basis for ameliorating immunopathology. Expulsion of the side chain upon opening of the beta-lactam ring retained antibacterial activity while safely expelling the immunodominant epitope. L-786,392 was well tolerated in animal safety studies and had significant in vitro and in vivo activities against methicillin- and vancomycin-resistant Staphylococci and vancomycin-resistant Enterococci. 相似文献
993.
CJ Gordon MA Muesing AE Proudfoot CA Power JP Moore A Trkola 《Canadian Metallurgical Quarterly》1999,73(1):684-694
We have studied the effects of CC-chemokines on human immunodeficiency virus type 1 (HIV-1) infection, focusing on the infectivity enhancement caused by RANTES. High RANTES concentrations increase the infectivity of HIV-1 isolates that use CXC-chemokine receptor 4 for entry. However, RANTES can have a similar enhancing effect on macrophagetropic viruses that enter via CC-chemokine receptor 5 (CCR5), despite binding to the same receptor as the virus. Furthermore, RANTES enhances the infectivity of HIV-1 pseudotyped with the envelope glycoprotein of murine leukemia virus or vesicular stomatitis virus, showing that the mechanism of enhancement is independent of the route of virus-cell fusion. The enhancing effects of RANTES are not mediated via CCR5 or other known chemokine receptors and are not mimicked by MIP-1alpha or MIP-1beta. The N-terminally modified derivative aminooxypentane RANTES (AOP-RANTES) efficiently inhibits HIV-1 infection via CCR5 but otherwise mimics RANTES by enhancing viral infectivity. There are two mechanisms of enhancement: one apparent when target cells are pretreated with RANTES (or AOP-RANTES) for several hours, and the other apparent when RANTES (or AOP-RANTES) is added during virus-cell absorption. We believe that the first mechanism is related to cellular activation by RANTES, whereas the second is an increase in virion attachment to target cells. 相似文献
994.
EM van Lieshout HM Roelofs S Dekker CJ Mulder T Wobbes JB Jansen WH Peters 《Canadian Metallurgical Quarterly》1999,59(3):586-589
Factors determining individual susceptibility to esophageal cancer or premalignant Barrett's epithelium are still largely unclear. An imbalance between phase I drug metabolism [e.g., cytochrome P450 (CYP)] and phase II detoxification [e.g., glutathione S-transferase (GST)] may contribute to the development of these diseases. Polymorphic variants in the CYP1A1 gene were described leading to increased levels of bioactive compounds, whereas polymorphisms in GST genes often resulted in impaired detoxification. We studied the frequencies of polymorphic variants in CYP1A1, GSTP1, GSTT1, and GSTM1 genes in 98 patients with Barrett's epithelium and 34 patients with esophageal cancer. The results were compared with those obtained from 247 healthy blood donors. DNA was extracted, and PCR-RFLP methods were used to detect genetic polymorphisms. Chi2 analysis, Spearman rank correlation, and Wilcoxon rank sum tests were used for statistical evaluation. Polymorphisms in CYP1A1, GSTM1, and GSTT1 occurred at an equal frequency in patients and controls. Occurrence of the polymorphic GSTP1b variant in the GSTP1 gene resulted in a significantly lower GST enzyme activity (P < 0.05), and GSTP1b was found significantly more often in patients with Barrett's epithelium (70%; P < 0.001) and patients with esophageal adenocarcinoma (76%; P = 0.005), as compared to healthy blood donors (41%). In conclusion, presence of the GSTP1b allele leads to lower GST enzyme activity levels and, consequently, impaired detoxification. This most important esophageal GST isoform may, therefore, contribute to the development of Barrett's epithelium and adenocarcinoma. 相似文献
995.
JM Balter KL Lam CJ McGinn TS Lawrence RK Ten Haken 《Canadian Metallurgical Quarterly》1998,41(4):939-943
PURPOSE: CT-based models of the patient that do not account for the motion of ventilation may not accurately predict the shape and position of critical abdominal structures. Respiratory gating technology for imaging and treatment is not yet widely available. The purpose of the current study is to explore an intermediate step to improve the veracity of the patient model and reduce the treated volume by acquiring the CT data with the patients holding their breath at normal exhale. METHODS AND MATERIALS: The ventilatory time courses of diaphragm movement for 15 patients (with no special breathing instructions) were measured using digitized movies from the fluoroscope during simulation. A subsequent clinical protocol was developed for treatment based on exhale CT models. CT scans (typically 3.5-mm slice thickness) were acquired at normal exhale using a spiral scanner. The scan volume was divided into two to three segments, to allow the patient to breathe in between. Margins were placed about intrahepatic target volumes based on the ventilatory excursion inferior to the target, and on only the reproducibility of exhale position superior to the target. RESULTS: The average patient's diaphragm remained within 25% of the range of ventilatory excursion from the average exhale position for 42% of the typical breathing cycle, and within 25% of the range from the average inhale position for 15% of the cycle. The reproducibility of exhale position over multiple breathing cycles was 0.9 mm (2sigma), as opposed to 2.6 mm for inhale. Combining the variation of exhale position and the uncertainty in diaphragm position from CT slices led to typical margins of 10 mm superior to the target, and 19 mm inferior to the target, compared to margins of 19 mm in both directions under our prior protocol of margins based on free-breathing CT studies. For a typical intrahepatic target, these smaller volumes resulted in a 3.6% reduction in Veff for the liver. Analysis of portal films shows proper target coverage for patients treated based on exhale modeled plans. CONCLUSIONS: Modeling abdominal treatments at exhale, while not realizing all the gains of gated treatments, provides an immediate reduction in the volume of normal tissue treated, and improved reliability of patient data for NTCP modeling, when compared to current "free breathing" CT models of patients. 相似文献
996.
RP Liberman CJ Wallace G Blackwell A Kopelowicz JV Vaccaro J Mintz 《Canadian Metallurgical Quarterly》1998,155(8):1087-1091
OBJECTIVE: The authors compared the community functioning of outpatients with persistent forms of schizophrenia after treatment with psychosocial occupational therapy or social skills training, with the latter conducted by paraprofessionals. METHOD: Eighty outpatients with persistent forms of schizophrenia were randomly assigned to receive either psychosocial occupational therapy or skills training for 12 hours weekly for 6 months, followed by 18 months of follow-up with case management in the community. Antipsychotic medication was prescribed through "doctor's choice" by psychiatrists who were blind to the psychosocial treatment assignments. RESULTS: Patients who received skills training showed significantly greater independent living skills during a 2-year follow-up of everyday community functioning. CONCLUSIONS: Skills training can be effectively conducted by paraprofessionals, with durability and generalization of the skills greater than that achieved by occupational therapists who provide their patients with psychosocial occupational therapy. 相似文献
997.
To understand the healthy life style, health status and risk factors of employees, institutional employees in Kaohsiung area were studied by using questionnaire investigation and blood specimen examination. One-thousand-four hundred-fifty subjects were used, but 1147 questionnaires were completed. The complete rate was 79.1%. The reliability and validity of the healthy life style scale achieved an acceptable level. The results are as follows: 1. The mean total score of healthy life-style scale was 63.9. Four healthy behavior scored lowest: "consulted health professional about health information", "monitored self of blood pressure and blood sugar", did moderate exercise at least three times per week", "took leisure activities". 2. The severity of risk factor was as follows: (1) 32.2% of employees had abnormal value for blood cholesterol (> or = 200 mg/dl); (2) 22.9% of employees had abnormal blood pressure value; (3) 22.6% of employees were overweight or obese; (4) 16.7% of employees often smoked; (5) 13.6% of employees had abnormal values for blood triglyceride. (6) 2.1% of employees had abnormal blood sugar values. 3. 10.8% of subjects were perceieved to have a worsing health status; 14.5% of the subjects had chronic disease with physicians diagnosis and most of their (71%) were hypertersion. 4. The findings of demographic data showed that people who were male, aged over forty, had education below junior high school and those of blue collar class should be screened and monitored, for the risk factors at regular intervals. Similarly, People who are male, age below forty and blue-collar class should be encouraged to develop the healthy life-styles. 相似文献
998.
Difficult-to-manage mucosal candidal infection has been a hallmark of individuals with advanced infection due to human immunodeficiency virus type 1. In this AIDS Commentary, Drs. Fichtenbaum and Powderly comprehensively review the literature and their experience with refractory candidiasis in such patients. Of interest is their delineation of resistance, a lack of susceptibility to an antifungal agent in vitro among patients with refractory or clinically unresponsive disease. These authors believe that the establishment of resistance should be based upon standards established by the National Committee on Clinical Laboratory Standards, which they propose to define as a failure to respond to systematic therapy with specific doses of itraconazole, fluconazole, or parenterally or orally administered amphotericin B within 14 days. There have been many definitions of "refractory candidiasis," and the one proposed by these authors will be debated; however, this definition has the advantage of establishing a standard by which to judge the efficacy of their proposed algorithm for the treatment of persistent or refractory oropharyngeal candidal infections. Drs. Fichtenbaum and Powderly have performed a useful service in their attempt to bring coherence to the management of this common and often vexing problem. 相似文献
999.
The Ethical Principles exhort psychologists "to encourage ethical behavior by students, supervisees, employees, and colleagues, as appropriate" (American Psychological Association, 1992, p. 1599). In spite of a clear directive to attempt resolution of unethical conduct by colleagues, research indicates that satisfactory resolution or actual reporting of misconduct is infrequent. This paper will address some of the forces that discourage psychologists from dealing responsibly and appropriately with professional misconduct by colleagues. The goals of this paper are to promote understanding of factors that interfere with the effective resolution of ethical misconduct, to identify possible signs of reluctance to address misconduct, and to propose strategies to combat those forces that keep us in silent collusion with colleagues who engage in unethical practices. A flowchart of steps for addressing possible misconduct by a colleague is provided, and educational, organizational, and professional considerations are discussed. 相似文献
1000.
We report a quantitative analysis of the major populations of cells present in the retina of the C57 mouse. Rod and cone photoreceptors were counted using differential interference contrast microscopy in retinal whole mounts. Horizontal, bipolar, amacrine, and Müller cells were identified in serial section electron micrographs assembled into serial montages. Ganglion cells and displaced amacrine cells were counted by subtracting the number of axons in the optic nerve, learned from electron microscopy, from the total neurons of the ganglion cell layer. The results provide a base of reference for future work on genetically altered animals and put into perspective certain recent studies. Comparable data are now available for the retinas of the rabbit and the monkey. With the exception of the monkey fovea, the inner nuclear layers of the three species contain populations of cells that are, overall, quite similar. This contradicts the previous belief that the retinas of lower mammals are "amacrine-dominated", and therefore more complex, than those of higher mammals. 相似文献