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51.
Education and other strategies to promote optimal complementary feeding can significantly improve practices, but little is known about the specific techniques successful interventions use to achieve behaviour change. We reviewed the literature for complementary feeding interventions in low‐/middle‐income countries (LMIC) published since 2000. We systematically applied a validated taxonomy mapping process to code specific behaviour change techniques (BCTs) used in each intervention; effectiveness ratios for each BCT were estimated. Sixty‐four interventions met inclusion criteria, were abstracted, BCTs identified, and coded. Dietary diversity was the most commonly assessed component of complementary feeding, and interpersonal communication, either individually or in groups, was the most commonly used delivery platform. Of the 93 BCTs available for mapping, the 64 interventions included in this review applied a total of 28 BCTs. Interventions used a median of six techniques (max = 13; min = 2). All interventions used “instruction on how to perform the behaviour.” Other commonly applied BCTs included “use of a credible source” (n = 46), “demonstration of the behaviour” (n = 35), and “providing information about health consequences” (n = 30). Forty‐three interventions reported strategies to shift the physical or social environment. Among BCTs used in >20 interventions, five had effectiveness ratios >0.8: “provision of/enabling social support”; “providing information about health consequences”; “demonstration of the behaviour”; and “adding objects to the environment” namely, food, supplements, or agricultural inputs. The limited reporting of theory‐based BCTs in complementary feeding interventions may impede efforts to improve and scale effective programs and reduce the global burden of malnutrition.  相似文献   
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MRS of 13C4‐labelled glutamate (13C4‐Glu) during an infusion of a carbon‐13 (13C)‐labelled substrate, such as uniformly labelled glucose ([U‐13C6]‐Glc), provides a measure of Glc metabolism. The presented work provides a single‐shot indirect 13C detection technique to quantify the approximately 2.51 ppm 13C4‐Glu satellite proton (1H) peak at 9.4 T. The methodology is an optimized point‐resolved spectroscopy (PRESS) sequence that minimizes signal contamination from the strongly coupled protons of N‐acetylaspartate (NAA), which resonate at approximately 2.49 ppm. J‐coupling evolution of protons was characterized numerically and verified experimentally. A (TE1, TE2) combination of (20 ms, 106 ms) was found to be suitable for minimizing NAA signal in the 2.51 ppm 1H 13C4‐Glu spectral region, while retaining the 13C4‐Glu 1H satellite peak. The efficacy of the technique was verified on phantom solutions and on two rat brains in vivo during an infusion of [U‐13C6]‐Glc. LCModel was employed for analysis of the in vivo spectra to quantify the 2.51 ppm 1H 13C4‐Glu signal to obtain Glu C4 fractional enrichment time courses during the infusions. Cramér‐Rao lower bounds of about 8% were obtained for the 2.51 ppm 13C4‐Glu 1H satellite peak with the optimal TE combination.  相似文献   
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In C. elegans, neurodegeneration induced by excitotoxicity or aggregation of misfolded proteins is dependent on genes involved in calcium release from the endoplasmic reticulum. Reactive oxygen species (ROS) can also induce neurodegeneration, but the relationship between ROS-mediated neurodegeneration and calcium has not been established. We activated KillerRed in the GABA neurons of C. elegans to produce ROS that leads to functional loss and structural degeneration of these neurons and demonstrated that the severity of neurodegeneration was dependent on extent of KillerRed activation. To genetically examine the role of calcium in ROS-mediated neurodegeneration, we measured functional neurodegeneration in itr-1 (inositol trisphosphate receptor), crt-1 (caltreticulin), and unc-68 (ryanodine receptor) mutants. Similar to other neurotoxic conditions, neurodegeneration triggered by KillerRed was reduced in itr-1 and crt-1 mutants. Somewhat unexpectedly, genetic or pharmacological disruption of unc-68 had a minimal effect on neurodegeneration. Our results indicate ROS-mediated neurodegeneration occurs through a conserved calcium regulated mechanism and suggest that components of the degeneration process have different sensitivities to ROS.  相似文献   
56.
Three-dimensional (3?D) hydrogel scaffolds are an attractive option for tissue regeneration applications because they allow for cell migration, fluid exchange, and can be synthesized to closely mimic the physical properties of the extracellular matrix environment. The material properties of hydrogels play a vital role in cellular migration and differentiation. In light of this, in-depth understanding of material properties is required before such scaffolds can be used to study their influence on cells. Herein, various blends and thicknesses of poly (ethylene glycol) dimethacrylate (PEGDMA) hydrogels were synthesized, flash frozen, and dried by lyophilization to create scaffolds with multiscale porosity. Environmental scanning electron microscopy (ESEM) images demonstrated that lyophilization induced microporous voids in the PEGDMA hydrogels while swelling studies show the hydrogels retain their innate swelling properties. Change in pore size was observed between drying methods, polymer blend, and thickness when imaged in the hydrated state. Human adipose-derived stem cells (hASCs) were seeded on lyophilized and non-lyophilized hydrogels to determine if the scaffolds would support cell attachment and proliferation of a clinically relevant cell type. Cell attachment and morphology of the hASCs were evaluated using fluorescence imaging. Qualitative observations in cell attachment and morphology of hASCs on the surface of the different hydrogel spatial configurations indicate these multiscale porosity hydrogels create a suitable scaffold for hASC culture. These findings offer another factor of tunability in creating biomimetic hydrogels for various tissue engineering applications including tissue repair, regeneration, wound healing, and controlled release of growth factors.  相似文献   
57.
Frequency and perception of cough severity   总被引:4,自引:0,他引:4  
OBJECTIVE: The frequency of the common symptom of cough in children is unknown. The aim of this study was to compare cough frequency and perception of cough severity in children with and without recurrent cough. METHODOLOGY: Eighty-four children with (C) and without (NC) recurrent cough were recruited in the same season. Cough frequency (measured with cough-meter) and subjective cough severity (measured on parent-completed and child-completed diary cards on two subjective systems), were compared between the two groups. RESULTS: Cough frequency in C (median 65/day) was significantly higher than in NC (10/day). The correlation between daytime and night-time cough was higher in NC (rs = 0.51, P < 0.00001) than in C (rs = 0.3, P = 0.05). The C group had significantly higher coughs per score than NC, for both subjective methods. CONCLUSIONS: Children with recurrent cough have a higher frequency and different pattern of cough than controls enrolled in the same season. Subjective perception of cough severity is dependent on the population studied.  相似文献   
58.
Intra-abdominal infection continues to pose a significant threat to critically ill patients in the year 2000. A review of the current literature reveals that despite remarkable developments in critical care medicine and extensive study of patients with tertiary peritonitis, the associated mortality rate remains nearly 30%. Progress has been limited by the difficulty of comparing heterogeneous patient populations, groups that manifest a host of comorbid, potentially confounding illnesses. Additionally, debate persists regarding the definitions of secondary and tertiary peritonitis, resulting in varied study inclusion criteria, and further complicating data analysis and interpretation. Scoring systems developed to identify those patients at risk for progression to tertiary peritonitis, the more chronic, lethal form of intra-abdominal infection associated with multisystem organ failure, reflect the current emphasis in the literature on the importance of early diagnosis and early intervention. This has led to a renewed interest in conservative, data-dependent surgical management employing radiographic and microbiologic evidence to guide therapy.  相似文献   
59.
BACKGROUND: Multidrug resistance among gram-positive pathogens in tertiary and other care centers is common. A systematic decision pathway to help select empiric antibiotic therapy for suspected gram-positive postsurgical infections is presented. DATA SOURCES: A Medline search with regard to empiric antibiotic therapy was performed and assessed by the 15-member expert panel. Two separate panel meetings were convened and followed by a writing, editorial, and review process. CONCLUSIONS: The main goal of empiric treatment in postsurgical patients with suspected gram-positive infections is to improve clinical status. Empiric therapy should be initiated at the earliest sign of infection in all critically ill patients. The choice of therapy should flow from beta-lactams to vancomycin to parenteral linezolid or quinupristin-dalfopristin. In patients likely to be discharged, oral linezolid is an option. Antibiotic resistance is an important issue, and in developing treatment algorithms for reduction of resistance, the utility of these new antibiotics may be extended and reduce morbidity and mortality.  相似文献   
60.
A novel protein MGC5306 has been identified in yeast-two-hybrid analysis by screening a HeLa cDNA library with a truncated DNA polymerasebeta (polbetaDelta) as bait. The polbetaDelta is expressed in various types of cancers. Co-immunoprecipitation-Western blot analysis confirms not only its interaction with polbetaDelta but also with wild-type polbeta. Binding to polbeta indicates potential function of MGC5306 in repair pathway. Transfection of cells with MGC5306-GFP and Western blot analysis with anti-MGC5306 antibody reveal its nuclear localization. MGC5306 is expressed in human carcinomas and tumor cell lines but not in normal tissues, suggesting MGC5306 is most likely involved in carcinogenesis. An antigrowth activity and modulations of cell cycle events are identified in cells expressing siRNAMGC5306.  相似文献   
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