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961.
962.
The aims of this study were to compare diagnostic accuracy, cost, and patient tolerance of videoesophagography and esophageal transit scintigraphy to esophageal manometry in the evaluation of nonobstructive esophageal dysphagia. Eighty-nine consecutive patients underwent videoesophagography, scintigraphy, and manometry. The sensitivities for diagnosing specific esophageal motility disorders, using esophageal manometry as the standard, were 75% and 68% for videoesophagography and scintigraphy, respectively, with positive predictive accuracies of 96% and 95% for achalasia, 100% and 67% for diffuse esophageal spasm, 100% and 75% for scleroderma, 50% and 67% for isolated LES dysfunction, 57% and 48% for nonspecific esophageal motility disorders, and 70% and 68% for normal esophageal motility. The cost for videoesophagography is less than that for either manometry or scintigraphy. Both videoesophagography and scintigraphy were better tolerated than manometry. It is concluded that videoesophagography and scintigraphy accurately diagnose primary esophageal motility disorders, achalasia, scleroderma, and diffuse esophageal spasm, but are less accurate in distinguishing nonspecific esophageal motility disorders from normal. When considering accuracy, cost, and patient acceptance, these findings suggest that videoesophagography is a useful initial diagnostic study for the evaluation of nonobstructive esophageal dysphagia.  相似文献   
963.
Twenty patients on long-term treatment with lithium who had persistently elevated neutrophil counts were challenged with adrenalin and hydrocortisone to measure their marginal and bone marrow granulocyte pools. Compared with normal controls the results suggest that the absolute numbers of granulocytes in each pool are not increased, although the percentage change is diminished because of the greater baseline values in the experimental group. These data suggest that lithium acts on granulopoiesis within the bone marrow, and are in keeping with the concept that the granulocyte reserve has a finite size. There is no apparent connection between lithium-induced neutrophilia and either the therapeutic or unwanted effects of lithium.  相似文献   
964.
Cell contact with the extracellular matrix component, hyaluronan, plays a pivotal role in glioma cell invasion and proliferation. Although it is well established that glioma cells can bind hyaluronan to their surface via the expression of CD44, the cellular responses following ligand-receptor interaction remain poorly understood. Given that a large proportion of human high grade gliomas over express the epidermal growth factor receptor (EGFR) and ErbB2, this study aimed to investigate whether an interaction exists between CD44 and these receptor tyrosine kinases. Here we present evidence that CD44 co-immunoprecipitates with EGFR and ErbB2 in the glioma cell lines U87MG and SMA560. Hyaluronan treatment mediated the rapid and transient phosphorylation of extracellular signal regulated kinases 1 and 2 (ERK1 and ERK2) in glioma cell lines. This response to hyaluronan was augmented by the co-expression of EGFR. EGFR also differentially modified the hyaluronan induced expression of a number of genes associated with cellular invasion and proliferation. Northern blot analysis demonstrated that genes encoding urokinase type plasminogen activator (uPA), urokinase type plasminogen activator receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), tissue inhibitor of metalloproteinases (TIMP-1) and c- myc were up-regulated in response to hyaluronan. Furthermore, zymographic analysis revealed increased levels of uPA in the conditioned medium of hyaluronan stimulated cells. These results indicate a novel functional relationship between CD44 and EGFR in glioma cell lines. The capacity of CD44 to form stable complexes with receptor tyrosine kinases may provide a versatile system for the regulation of cellular invasion and proliferation that allows hyaluronan to activate signal transduction pathways and modulate gene expression via an EGFR-dependent manner. These findings provide new insights into the mode by which hyaluronan regulates the malignant phenotype and also suggest a role for EGFR-CD44 interactions in glial tumorigenesis.  相似文献   
965.
Verapamil and diltiazem are effective in terminating paroxysmal supraventricular tachycardias and slowing ventricular response during atrial fibrillation or flutter. Results from clinical trials for each individual drug demonstrate comparative efficacy rates, and both drugs share the same contraindications and relative precautions. Well-designed comparative clinical trials are needed to establish if either drug has any clinical advantages in a particular patient population.  相似文献   
966.
A prospective study of 20 patients was conducted to determine changes in the computed tomography appearance of glioblastomas seen at the completion of radiation therapy. An interval CT was obtained after 4000 to 4500 cGy to the whole brain and was compared to a similar baseline study. The tumor volume increased in twelve patients by 13 to 878% (mean 126%) and decreased in seven by 13 to 73% (mean 37%). It remained unchanged in one patient. A broadening or thinning of the enhancing rim frequently accompanied the increased or decreased tumor, respectively. Volume change immediately after whole brain radiotherapy was no prognostic indicator. The volume increase seen in 60% of the patients had implications for treatment planning of the boost field. It translated into a potential field size increase of up to 5.6 cm (mean 3.5 cm) and could contribute to a geographic miss. It is concluded that following whole brain radiation therapy, a repeat CT scan or magnetic resonance imaging, depending on the initial exam, is necessary for optimal planning of the reduced radiation field.  相似文献   
967.
The authors present the case of a thirteen-year-old boy with aortic coarctation, which was surgically corrected at the age of 2.5 months. He subsequently developed recoarctation, which was treated with balloon dilatation. Recently, recoarctation and an aortic aneurysm were observed, which were corrected with covered stent implantation. We discuss various techniques for correction of aortic coarctation, as well as their advantages and disadvantages.  相似文献   
968.
PURPOSE: To evaluate the importance of 13 items in the recruitment and retention of HIV-positive and HIV-negative adolescent participants in a longitudinal study (REACH study). METHODS: A confidential, self-administered, visual analog, cross-sectional survey was offered to active participants (November 1999-August 2000) with 438 subjects (86%) participating. Sixty-six percent of the cohort were HIV-positive and 34% were HIV-negative with a mean age of 17 years, and 76% were female. Subjects were asked to recall the importance they placed on 13 items in deciding to join the REACH study (recruitment) and to remain on study (retention). Factors that might explain the judgment placed on the items were analyzed using the nonparametric Wilcoxon Rank-Sum test or the Kruskall-Wallis test. RESULTS: The five most important factors for study recruitment were identical to those chosen for retention by participants. The factors were: (a) quality medical care, (b) caring staff, (c) health education, (d) privacy/confidentiality, and (e) altruism. Items judged least important were social activities, compensation, transportation, and food/meals. Subject characteristics (gender, age, HIV status) were not associated with statistically different mean judgment scores at recruitment and retention, although clinical site showed significant variation. Factors that could render subjects vulnerable (health insurance, family finances) were not associated with related items. CONCLUSIONS: Adolescents found quality health care and care team characteristics critically important in considering research participation. Attention to privacy and the opportunity to be altruistic were also important. Compensation for participation was not a significant factor for recruitment and retention of this adolescent cohort. This study demonstrates that adolescents apply sound criteria in evaluating research participation and do not appear to be unduly affected by compensation.  相似文献   
969.
To assess the influence of postinspiratory apnea on the measurement of the left ventricular volumes, contrast ventriculography was performed on 19 patients during spontaneous breathing and then in postinspiratory apnea. Data obtained were similar for end diastolic volumes (81±29 ml/m2 vs. 83±25; NS), end systolic volumes (35±20 ml/m2 vs. 34±19; NS), systolic index (46±13 ml/m2 vs. 49±12; NS), and ejection fraction (0.57±0.11 vs. 0.59±0.12; NS). Postinspiratory apnea suppressed the overlapping of the left ventricle with abdominal viscera in 15 of 17 patients. Diaphragmatic immobility permitted the assessment of regional left ventricular function in all 19 patients. However, pressures recorded in inspiratory apnea can no longer be compared to a transmural pressure, and, to assess ventricular compliance, intrapleural pressure must be measured simultaneously. We conclude that left ventricular volume assessment by contrast ventriculography is not disturbed by inspiratory apnea. This maneuver improves the quality of the images and allows a better evaluation of left ventricular segmental function. Spontaneous breathing can be recommended to simplify left ventricular complicance study.  相似文献   
970.
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