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1.
Inhibitors of the IIB-IIIA integrin are widely used to prevent stent thrombosis. Abciximab has been shown to attenuate the inflammatory response in patients undergoing PCI. Herein, we tested the effect of eptifibatide infused during PCI on peripheral lymphocyte activation and CRP levels before, and one month after the procedure showing no noticeable effect. These results may explain the differences in clinical outcome following PCI by use of different IIB-IIIA agents. (Int J Cardiovasc Intervent 2004; 6: 107-109)  相似文献   
2.
Systemic sclerosis (SSc) is an autoimmune systemic connective tissue disorder characterized by sclerotic change of the skin and multiple internal organs. Although the pathogenesis of this disorder is still unknown, overproduction of extracellular matrix proteins, including collagens and fibronectin, and aberrant immune activation may be involved in the mechanism. Interleukin (IL)‐1 is one of the key regulators of inflammatory response. IL‐1 is also involved in regulating connective tissue remodeling and cellular differentiation of epithelial and ectodermal cells. There are three major members of the IL‐1 family: IL‐1α, IL‐1β and IL‐1 receptor antagonist. IL‐1α was first described as a factor derived from keratinocytes that stimulates thymocyte proliferation. IL‐1α plays a crucial role in procollagen production by fibroblasts derived from patients with SSc. The present study was undertaken to investigate the serum levels of IL‐1α in patients with SSc. Serum samples were obtained from 66 Japanese patients with SSc and 19 healthy controls. Levels of serum IL‐1α were measured with a specific enzyme‐linked immunoassay kit. Mean serum levels were significantly higher in SSc patients than in those healthy control subjects. Moreover, contracture of phalanges was found at a significantly lower prevalence in SSc patients with elevated serum IL‐1α levels than those with normal levels. These results suggest that IL‐1α may play a role in the pathogenesis of SSc.  相似文献   
3.
Exposure to ultraviolet radiation can lead to suppression of many adaptive immune responses, both to antigens encountered within a short period of the irradiation (primary) and to antigens previously encountered (memory). The pathways involved are complex and not completely elucidated. This brief review summarizes the information available currently regarding the multiple steps involved, with the aim of providing a general overview of the main aspects of photoimmunosuppression and its clinical consequences.  相似文献   
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Neonatal exposure to intermittent hypoxia results in altered ventilatory response to subsequent hypoxia in animal models. The effect of similar exposure in human infants is unknown. Our objective was to determine the impact of sleep disordered breathing (SDB) in early infancy on ventilatory response in infants. We recruited consecutive infants with cleft lip and/or palate (CL/P) to undergo ventilatory response testing using exposure to a hypoxic (15% O2) gas mixture during sleep. This population is at high risk of SDB because of smaller airway caliber and abnormal palatal muscle attachments predisposing them to airway obstruction of ranging severity from birth. Ventilatory responses were compared between infants with a low apnea–hypopnea index (AHI; AHI < 15 events/hr) and a high AHI (AHI ≥ 15 events/hr). Testing was successfully completed in 22 of 23 infants who underwent testing at 4.4 ± 4.8 months. Infants with high AHI had lower weight z‐scores, higher number of oxygen desaturation events during sleep, but similar oxygen saturation (SpO2) nadir compared to infants with low AHI. The pattern of ventilatory response to hypoxia differed between the two groups; infants with high AHI had an earlier ventilatory decline and a blunted maximal ventilatory response to hypoxia. Infants with a high AHI use a different strategy to augment ventilation in response to hypoxia; while infants with a low AHI initially increased respiratory rate, tidal volume was the first parameter to increase in infants with high AHI. These results demonstrate that SDB in infancy is associated with altered ventilatory response to hypoxia. Pediatr Pulmonol. 2013; 48:265–273. © 2012 Wiley Periodicals, Inc.  相似文献   
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Introduction: Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common acquired immune‐mediated inflammatory disorder of the peripheral nervous system. The diagnosis is based mainly on the clinical presentation and electrophysiological detection of demyelination. Methods: Several MRI studies have demonstrated hypertrophy and abnormal enhancement of spinal nerve roots or brachial plexus in CIDP, but there have been only anecdotal reports of similar sonographic findings. Results: This article reports the sonographic findings of a CIDP case and includes a review of the literature and previously reported cases. Conclusions: This case report highlights the importance of sonography in the localization and recognition of focal nerve enlargements in patients with CIDP. This method could be a helpful tool in the diagnosis of conduction block in CIDP, especially in cases where a nerve segment cannot be explored easily with the inching technique. Systematic data are needed to confirm this observation. Muscle Nerve 47:443‐446, 2013  相似文献   
9.
Purpose: To study whether fragile histidine triad (Fhit) prevents IR-induced hypoxanthineguanine phosphoribosyltransferase (HPRT) mutation and whether Fhit plays any role in preventing HPRT mutation through low dose-induced adaptive response.

Materials and methods: Establishing human cell lines with or without Fhit expression by making constructs expressing hemagglutinin (HA) alone or HA-Fhit fusion protein and transfecting the vector to HeLa cells. The effects of Fhit on ionising radiation (IR)-induced mutation were examined by observing HPRT mutation rates in the established cell lines following different doses of IR. The role of Fhit on low dose IR-induced adaptive response were examined by observing HPRT mutation rates in the established cell lines that were exposed to 0.1 Gy and followed with high dose IR or ultraviolet (UV) exposure.

Results: Low dose (0.1 Gy) does not affect HPRT mutation rates in these cell lines. Fhit prevents high dose IR (≥2 Gy)-induced mutation as it prevents UV-induced mutation. However, low dose of IR (0.1 Gy)-induced adaptive response prevents both high doses of IR and UV-induced mutation in both the cells with and without Fhit expression.

Conclusions: Fhit prevents IR-induced HPRT mutation and preventing mutation through low dose of IR-induced adaptive response is Fhit independent.  相似文献   
10.
Purpose: The objective of this study was to investigate how Escherichia coli cells responded at the level of DNA repair, when the cells were subjected to UV (ultraviolet) radiation and heat-stress to induce a DNA repair system (SOS) and heat-shock response, respectively.

Materials and methods: The experiments were performed to study the Weigle reactivation of the bacteriophage ?X174 in its host E. coli C/1 cells. Two distinct techniques, top layer agar plating and Western blotting, were employed to measure the plaque count of viable phages and to demonstrate the heat-shock response respectively.

Results: Repair of UV-inactivated bacteriophages in UV-irradiated E. coli cells is known as Weigle reactivation. In the case of the single-stranded DNA containing bacteriophage ?X174, Weigle reactivation occurs only through the inducible SOS repair response. Here we report that when UV-irradiated E. coli cells were transferred to higher temperature, the consequent heat-shock enhanced the reactivation of UV-inactivated ?X174 over normal Weigle reactivation; the enhancement being maximum when the cells were shifted from 30 – 47°C and incubated there for 30 min. The extent of increase of reactivation was less, when the cells were first subjected to heat-shock and then irradiated by UV. Besides heat, ethanol (5 – 10% volume/volume [v/v]), an established heat-shock inducer, also caused enhancement of phage reactivation and the maximum enhancement occurred at 8% v/v ethanol.

Conclusion: We suggest that the SOS and heat-shock responses in E. coli act synergistically in the reactivation of UV-damaged bacteriophage ?X174.  相似文献   
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