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991.
正在我们的帮助下,掌握Photoshop和Adobe Camera RaW中的各类锐化与降噪技巧。几乎任何一张照片的处理都离不开降噪与锐化两大操作,这一点想必大家都有所体会。尤其是本文所使用的范例图片,额外的锐化能给鸟类华丽的羽毛带来锦上添花的效果。如何将高明的锐化技巧运用于自己的修片流程,是本文的重点。在这个过程中,大家将会接触到Photoshop CC中得到大幅改善的锐化和图片放大功能。教程所介绍的不同技巧是为了帮助大家掌握它们的使用方式,更重要的是理解它们的应用场合,而不是依葫芦画瓢在每幅照  相似文献   
992.
正我们来带领大家体验Lightroom中足以媲美Photoshop的图像调整能力,尤其是在调节色温与抑制画面眩光等方面。随着Photoshop的付费模式由过去的一次性付费变成按月付费,之前因为价格高不可攀而却步的人纷纷有些行动。但无论如何,这依旧不是一笔小钱。作为摄影师,我们是否真的需要Photosh0p,更便宜的Lightroom是  相似文献   
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The present study was performed to investigate left ventricular diastolic (LVD) function in hypertensive patients with unstable angina. Three groups of 17 patients each were studied. Group 1 consisted of hypertensives with unstable angina (HTU); group 2, normotensives with unstable angina (NTU); and group 3, untreated, uncomplicated hypertensives (HT). The LVD function was assessed echocardiographically by transmitral valve Doppler flow to measure the ratio between the early diastolic filling (E) and the atrial contraction phase (A). An E/A ratio of < 1 was suggestive of LVD dysfunction. Left ventricular mass (LVM), from an M-mode echocardiogram using the Penn-Cube formula, was corrected to body surface area (LVM/S) using a standard nomogram. Data are represented as median values and analyzed by Mann-Whitney test. P was significant at < .05. The HTU group had an E/A ratio of 0.8, and the NTU and HT groups had ratios of 1.17 and 1.1, respectively. There was significant diastolic dysfunction in the HTU group compared with the NTU and HT groups (P = .037 and .049, respectively). Although the LVM/S was significantly higher in the HTU group when compared with the HT group (110.6 and 96.9, respectively, P = .017), there was no significant difference between the HTU and NTU groups (123.1), P = .67. Hypertensive patients with unstable angina have significant LVD dysfunction that seems to be independent of LVM and ischemia. This may be attributable to increased stiffness of the left ventricle or structural left ventricular abnormalities.  相似文献   
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OBJECTIVE: More than 2700 lung transplants have been performed since the initial clinical success in 1983. The evolution in the techniques of lung transplantation and patient management and the effects on results are reviewed. SUMMARY BACKGROUND DATA: Improvements in donor management, lung preservation, operative techniques, immunosuppression management, infection prophylaxis and treatment, rejection surveillance, and long-term follow-up have occurred in the decade following the first clinically successful lung transplant. A wider spectrum of diseases and patients treated with lung transplant have accentuated the shortage of suitable lung donors. The organ shortage has led to the use of marginal donors and a limited experience using living, related donors. METHODS: Changes in techniques and patient selection and management are reviewed and controversial issues and problems are highlighted. RESULTS: One-year survival of greater than 90% for single-lung transplant recipients and greater than 85% for bilateral lung transplant recipients have been achieved. Complications caused by airway complications has been reduced greatly. Obliterative bronchiolitis develops in 20% to 50% of long-term survivors and is the leading cause of morbidity and mortality after the first year after transplant. CONCLUSIONS: Lung transplantation has evolved into an effective therapy for a wide variety of causes of end-stage lung disease. Wider applicability requires solutions to the problems of donor shortage and development of obliterative bronchiolitis.  相似文献   
997.
A method is described that allows the sequence-specific ligation of DNA. The method is based on the ability of RecA protein from Escherichia coli to selectively pair oligonucleotides to their homologous sequences at the ends of fragments of duplex DNA. These three-stranded complexes were protected from the action of DNA polymerase. When treated with DNA polymerase, unprotected duplex fragments were converted to fragments with blunt ends, whereas protected fragments retained their cohesive ends. By using conditions that greatly favored ligation of cohesive ends, a second DNA fragment could be selectively ligated to a previously protected fragment of DNA. When this second DNA was a vector, selected fragments were preferentially cloned. The method had sufficient power to be used for the isolation of single-copy genes directly from yeast or human genomic DNA, and potentially could allow the isolation of much longer fragments with greater fidelity than obtainable by using PCR.  相似文献   
998.
OBJECTIVE: To estimate the cost of adding IVF treatment to a standard health care benefits package. In vitro fertilization cost is defined as the average charge for a single cycle of treatment in an existing IVF program. DESIGN: Cost analysis. SETTING: Two hundred sixty IVF centers active in the United States in 1993. MAIN OUTCOME MEASURES: In vitro fertilization utilization and outcomes for 1993 were estimated from data in an existing registry. In vitro fertilization charges were determined from a 1993 survey of IVF clinics. The resulting expenditures for benefits and premiums were projected to 1995 together with the additional cost if utilization were to increase by 300% or 500%. RESULTS: In the United States in 1993 there were 31,718 IVF cycles for which the average charge was $6,233, leading to a total expenditure of approximately $197.70 million for IVF services in 1993. The projected cost of adding IVF services to a typical employer health plan in 1995 would be $2.79 per annum and the premium would be $3.14. Benefits and premium costs for a 300% utilization increase were $8.37 and $9.41, respectively, and for a 500% increase, $13.95 and $15.69, respectively. CONCLUSIONS: The cost of IVF services would be a minute fraction of the annual cost of a typical family benefits program ($3,393). Savings from reduced utilization of alternative treatments would offset a portion of this increase. Increases in utilization rates should be controlled by clinical criteria.  相似文献   
999.
1. Depolarization of mesangial cells has been shown to occur following an outward movement of chloride ions from the cell. We have shown previously that mesangial cells from the H-2Kb-tsA58 transgenic mouse possess a significant whole-cell chloride conductance and consequently are a suitable preparation for the study of potential chloride channel inhibitors. 2. The effects on the whole-cell chloride conductance of the chloride channel inhibitor, 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB) and the potassium channel openers, (KCOs) P1075 and pinacidil were investigated in mesangial cells from the H-2Kb-tsA58 transgenic mouse cultured in permissive conditions (at 33 degrees C in the presence of 50 u ml-1 murine gamma-interferon). 3. In symmetrical solutions of 140 mM tetramethylammonium chloride (TMAC1) the whole-cell chloride conductance was 1.08 +/- 0.05 nS (n = 63) and this could be reversibly inhibited by 5 x 10(-5) M NPPB. 4. Both P1075 and pinacidil inhibited the whole-cell chloride conductance. This inhibition was not reversible after drug washout and was demonstrated only when drugs were applied to the extracellular surface of the cells. Very low concentrations of the drugs were found to reduce the chloride conductance after 16 h incubation but under no circumstances studied was the conductance totally inhibited, leaving a mean residual current of 0.33 +/- 0.03 nS (n = 12). 5. The effects of different peptide calcium concentrations on the magnitude of the residual current in the presence of the drugs were investigated. The residual current was reduced with 10(-8) M calcium in the pipette and increased with 10(-3) M pipette calcium. Therefore, these data suggest that P1075 and pinacidil selectively inhibit a calcium-independent chloride conductance in mesangial cells from the H-2Kb-tsA58 transgenic mouse.  相似文献   
1000.
Circulating monocytes have a limited life span and will undergo apoptosis in the absence of specific stimuli. Recent studies have demonstrated that monocytes can be rescued from apoptosis via lipopolysaccharide (LPS) activation or stimulation with interleukin-1 or tumor necrosis factor-alpha. Based on previous studies from our laboratory, we hypothesized that, in nonseptic (e.g., autoimmune) inflammation, the presence of activated T cells may enhance monocyte longevity through T cell contact-dependent signaling. Plasma membranes prepared from 6 h activated (TmA) and resting (TmR) purified CD4+ T cells were added to resting elutriation-purified monocytes cultured in serum-free medium. Cells were assayed for degree of apoptosis occurring over a 72-h incubation using both agarose gel electrophoresis and flow cytometry. The addition of TmA (but not TmR) was capable of blocking monocyte apoptosis and the ability of TmA to rescue monocytes was abrogated by the addition of anti-CD40L antibodies. Rescue of monocytes from apoptosis could also be mediated by direct cross-linking of monocyte CD40. Inhibitors of tyrosine kinase activity blocked both TmA and anti-CD40-mediated rescue of monocytes from apoptosis, suggesting a primary role of a tyrosine kinase signaling pathway in the events controlling monocyte longevity.  相似文献   
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