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991.

Background  

The use of herbal supplements in the United States has become increasingly popular. The prevalence of herbal use among primary care patients varies in previous studies; the pattern of herbal use among urban racially/ethnically diverse primary care patients has not been widely studied. The primary objectives of this study were to describe the use of herbs by ethnically diverse primary care patients in a large metropolitan area and to examine factors associated with such use. The secondary objective was to investigate perceptions about and patterns of herbal use.  相似文献   
992.
A cognitive taxonomy of medical errors   总被引:1,自引:0,他引:1  
OBJECTIVE: Propose a cognitive taxonomy of medical errors at the level of individuals and their interactions with technology. DESIGN: Use cognitive theories of human error and human action to develop the theoretical foundations of the taxonomy, develop the structure of the taxonomy, populate the taxonomy with examples of medical error cases, identify cognitive mechanisms for each category of medical error under the taxonomy, and apply the taxonomy to practical problems. MEASUREMENTS: Four criteria were used to evaluate the cognitive taxonomy. The taxonomy should be able (1) to categorize major types of errors at the individual level along cognitive dimensions, (2) to associate each type of error with a specific underlying cognitive mechanism, (3) to describe how and explain why a specific error occurs, and (4) to generate intervention strategies for each type of error. RESULTS: The proposed cognitive taxonomy largely satisfies the four criteria at a theoretical and conceptual level. CONCLUSION: Theoretically, the proposed cognitive taxonomy provides a method to systematically categorize medical errors at the individual level along cognitive dimensions, leads to a better understanding of the underlying cognitive mechanisms of medical errors, and provides a framework that can guide future studies on medical errors. Practically, it provides guidelines for the development of cognitive interventions to decrease medical errors and foundation for the development of medical error reporting system that not only categorizes errors but also identifies problems and helps to generate solutions. To validate this model empirically, we will next be performing systematic experimental studies.  相似文献   
993.
Adherence to continuous positive airway pressure (CPAP) in patients with sleep apnea hypopnea syndrome (SAHS) is poor. Previous studies have attempted to identify specific barriers to treatment, but none has identified the sole cause for the problem. We outline a behavioral approach to the problem of CPAP adherence that is based on the theories of the transtheoretical model and social cognitive theory. We used these theories to guide the development of an intervention based on the methods of motivational interviewing. We present our motivational enhancement therapy for CPAP (ME-CPAP) here, with some brief pilot data to show its efficacy. Finally, we outline some strengths and weaknesses of taking a behavior change approach to the problem of poor CPAP adherence.  相似文献   
994.
Expressed sequence tags (ESTs) were produced from cDNA libraries for immature L1, mature muscle larva and adult stages of the adenophorean nematode Trichinella spiralis. 10,130 ESTs were grouped into 3454 gene clusters. The clusters represent a conservative estimate of 3262 unique genes. Interspecific comparisons of the predicted proteins support an ancient divergence of clade I nematodes from other nematodes in the phylum Nematoda. Furthermore, apparent clade I or Trichocephalida-specific proteins were identified, which may include molecular determinants important in the evolution of these species. Similarity matches identified 463 C. elegans genes homologs that confer phenotypes by RNA interference. Classification of predicted proteins suggested diverse cellular, metabolic and extracellular functions, significantly expanding the dataset of T. spiralis proteins with prospective, and potentially critical, functions. Several lines of evidence suggested stage-specific expression of certain genes beyond those previously identified. Evidence was obtained for the existence of large gene families encoding isoforms of known secreted proteins, such as p43 and TspE1. Unexpectedly, diverse isoforms of the muscle larva p43 gene appear to be expressed by immature L1. Proteinases, kinases, antioxidant proteins and enzymes involved in glycan synthesis are implicated in T. spiralis interactions with its hosts. Numerous genes were identified that encode predicted proteins in these categories. The genes discovered, when put into context of functional classification, stage of expression, and biology of the parasite, should substantially enhance experimental potential for research on this parasite.  相似文献   
995.
In order to understand how West Nile virus (WNV) has evolved since its introduction into North America, we have studied the genetic and phenotypic variation among WNV isolates collected in various areas during consecutive transmission seasons. The present report describes for the first time phenotypic changes occurring in the North American WNV population. Several isolates collected in Texas during 2003 display a small plaque (sp) and temperature sensitive (ts) phenotype, as well as reduced replication in cell culture, in comparison to isolates collected in 2002 and New York in 1999. Studies of mouse neuroinvasiveness/neurovirulence also indicate that several of these isolates were attenuated in neuroinvasiveness, but not for neurovirulence. The complete genome and deduced amino acid sequences of several of these isolates have been determined in order to map the mutations responsible for this phenotypic variation. These data indicate microevolution of WNV and the emergence of isolates exhibiting phenotypic variation.  相似文献   
996.
The hippocampus (HPC) has an essential role in relational memory. One task used to test relational memory is the transverse patterning (TP) problem (A+ B-, B+ C-, and C+ A-), which is sensitive to HPC damage across species. Using functional magnetic resonance imaging in humans, the authors observed activation maps and time course data indicating that the HPC is involved in this task, but it is paradoxically less active during the hippocampal-dependent relational memory phase relative to both a hippocampal-independent control memory phase and to a fixation control phase. This suggests that traditional assumptions suggesting that brain regions critical for a task must produce an increased blood oxygen level-dependent response during performance of that task are probably inaccurate and alternative explanations should be entertained.  相似文献   
997.
False memories in schizophrenia   总被引:2,自引:0,他引:2  
In prior studies, it was observed that patients with schizophrenia show abnormally high knowledge corruption (i.e., high-confident errors expressed as a percentage of all high-confident responses were increased for schizophrenic patients relative to controls). The authors examined the conditions under which excessive knowledge corruption occurred using the Deese-Roediger-McDermott paradigm. Whereas knowledge corruption in schizophrenia was significantly greater for false-negative errors relative to controls, no group difference occurred for false-positive errors. The groups showed a comparable high degree of confidence for false-positive recognition of critical lure items. Similar to findings collected in elderly participants, patients, but not controls, showed a strong positive correlation between the number of recognized studied items and false-positive recognition of the critical lure.  相似文献   
998.
BACKGROUND: The impact of metastasis to the retropharyngeal lymph node (RPLN) group is poorly understood because of the difficult access of the retropharyngeal space. Previous studies concluding to the negative impact of RPLN metastasis rely heavily on radiographic assessment, which introduces the possibility of diagnostic error. OBJECTIVE: To better define the prognostic significance of metastatic retropharyngeal adenopathy in patients with non-nasopharyngeal squamous cell carcinoma of the head and neck. STUDY DESIGN: A retrospective cohort study of patients with non-nasopharyngeal squamous cell carcinoma of the head and neck who underwent resection of the RPLN group and were followed up for an average of 24 months. SETTING: Tertiary care academic medical center. PATIENTS: The 51 patients included in the study had been treated for advanced-stage squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, and/or supraglottic larynx via a surgical approach to the primary tumor that afforded access to the RPLN group. All patients underwent dissection and pathologic interpretation of the RPLNs, most patients received postoperative radiotherapy, and 43 patients met survival analysis criteria. MAIN OUTCOME MEASURES: Local and regional recurrence rates, the development of distant metastasis, and disease-free and overall survival. RESULTS: Metastasis to the RPLN group was confirmed pathologically in 14 (27.5%) patients. There was no statistically significant difference between patients with and without RPLN metastasis in rates of local recurrence (24.8% vs 28.4%), regional recurrence (17.5% vs 19.6%), distant metastasis (17.0% vs 11.2%), disease-free survival (40.5% vs 30.5%), and overall survival (40.6% vs 38.5%). CONCLUSION: Metastasis to the RPLN group does not impact disease control or survival in patients with advanced non-nasopharyngeal squamous cell carcinoma of the head and neck treated with multimodality therapy.  相似文献   
999.
BACKGROUND: alpha2-Adrenergic blockade responses suggest adrenergic dysfunction in hypertension. alpha2-Blockade is also used to treat autonomic dysfunction. However, pharmacokinetic determinants of yohimbine disposition are not understood. METHODS: We evaluated alpha2-blockade with intravenous yohimbine in 172 individuals. Specific cytochrome P450 (CYP) isoform-mediated metabolism was investigated. Results were evaluated by ANOVA and by maximum likelihood analysis for bimodality of response distributions. RESULTS: Yohimbine metabolism to 11-hydroxy-yohimbine displayed greater than 1000-fold variability, with 17 individuals showing no metabolism. Nonmetabolizers differed from others in ethnicity but not in age, sex, body habitus, blood pressure, heart rate, or family history of hypertension. Bimodality of metabolism was suggested by frequency histogram, as well as maximum likelihood and cluster analysis. Among ethnic groups, subjects of European ancestry had the highest frequency of nonmetabolism. In vitro oxidation suggested that the major route of metabolism (lowest Michaelis-Menten constant and greatest intrinsic clearance) was likely via CYP2D6 to 11-hydroxy-yohimbine. In vivo genotypes at both CYP2D6 and CYP3A4 were necessary to predict metabolism (overall F = 3.03, P =.005); an interaction of alleles at these 2 loci (interaction F = 3.05, P =.033) suggested an epistatic effect on drug metabolism in vivo. Nonmetabolizers had greater activation of sympathetic nervous system activity. Yohimbine increased blood pressure, an effect mediated hemodynamically by elevation of cardiac output rather than systemic vascular resistance. Blood pressure and cardiac output responses did not differ by metabolizer group. CONCLUSIONS: We conclude that heterogeneous, bimodally distributed yohimbine metabolism depends on common genetic variation in both CYP2D6 and CYP3A4 and contributes to differences in sympathetic neuronal response to alpha2-blockade. These results have implications for both diagnostic and therapeutic uses of this alpha2-antagonist.  相似文献   
1000.
Ten patients with migraine with prolonged aura were studied for the presence of mitochondrial DNA point mutations utilizing DNA isolated from blood and hair samples. We analyzed for nine point mutations reported in patients with MELAS (A3243G, C3256T, T3271C, T3291C, A5814G, T8356C, T9957C, G13513A, and A13514G) and three secondary LHON mutations (T4216C, A4917G, and G13708A). None of the patients tested had any of these mutations in mitochondrial DNA. However, one patient was found to have a tRNA(Gln) A4336G mitochondrial DNA variant. From this study it appears that migraine with prolonged aura is not an oligosymptomatic form of MELAS and is not related to secondary LHON mutations. The significance of the tRNA A4336G variant is unknown.  相似文献   
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