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141.
Opinion statement Patients with hepatitis C virus (HCV) infection have a higher prevalence of psychiatric illness compared with the general US population, and the prevalence of HCV infection in patients with severe mental illness ranges between 8% and 19%, which is four to nine times that of the general US population (1.8%). Given the association between HCV infection and psychiatric illness, gastroenterologists are on the front line of identifying comorbid psychiatric and substance use disorders and conducting a psychosocial pretreatment risk-benefit assessment for HCV infection. The use of interferon-α (IFN)-based therapies in combination with ribavirin (RBV) to eradicate HCV has been associated with frequent neuropsychiatric adverse effects (eg, affective, anxiety, cognitive, and psychotic symptoms) that compromise the management of both HCV patients with and those without a preexisting history of psychiatric illness. Consequently, gastroenterologists have been reluctant to engage patients with HCV and comorbid psychiatric illness in antiviral treatment due to concerns about exacerbating or precipitating neuropsychiatric symptoms. Despite the clinical challenge that HCV treatment of patients with comorbid HCV and psychiatric illness presents, recent research indicates that HCV treatments can be safely administered to patients with psychiatric illness provided that there is a comprehensive pretreatment assessment, a risk-benefit analysis, and ongoing follow-up of neuropsychiatric symptoms during antiviral therapy. The process of pretreatment assessment involves screening patients for psychiatric and substance use disorders, educating patients about the treatment process, and addressing available psychosocial support. Most psychotropic medications (antidepressants, mood stabilizers, antipsychotics, and neuroleptics) are thought to be safe to use in the management of patients with HCV and psychiatric illness and for the management of IFN- and RBV-induced neuropsychiatric adverse effects. Nonetheless, the prophylactic use of psychotropic medications to prevent IFN- and RBV-induced neuropsychiatric adverse effects remains a controversial topic. The use of IFN and RBV in patients with HCV and severe mental illness can be done safely with expert psychiatric follow-up. In this review, we discuss the process of pretreatment assessment of patients with HCV and psychiatric illness and specifically address IFN- and RBV-induced depression in patients receiving HCV treatment.  相似文献   
142.
We assessed morbidity indicators for both Schistosoma haematobium and Schistosoma mansoni infections and evaluated the appropriateness of the World Health Organization (WHO) guidelines for ultrasound in schistosomiasis in the context of large-scale control interventions. Abdominal and urinary tract ultrasonography was performed on 2,247 and 2,822 school children, respectively, from 29 randomly selected schools in Mali before the implementation of mass anthelminthic drug administration. Using two-level logistic regression models, we examined associations of potential factors with the risk of having a positive ultrasound global score (morbidity indicative of S. haematobium infection), abnormal image pattern scores, dilatation of the portal vein, and/or enlarged liver (morbidity indicative of S. mansoni infection). The WHO protocol was found useful for detection of S. haematobium pathology but overestimated the risk of portal vein dilatation and left liver lobe enlargement associated with S. mansoni infection. We conclude that ultrasonography should be included in large-scale control interventions, where logistics allow, but cautiously.  相似文献   
143.
ObjectiveThe current study aimed at examining a fluoride containing bioactive glass (BiominF®) paste as a temporary filling material capable of remineralizing the demineralized enamel or dentin, and its ability to decrease a simulated dentinal fluids pressure on the resin/dentin interface, without affecting the shear bond strength of a universal bonding agent to enamel and dentin.Methods60 premolars were utilized for the acid resistance, trans-microradiography (TMR) and shear bond strength (SBS) experiments. Enamel and dentin discs were demineralized for 4 days to create a subsurface demineralized zone followed by applying BiominF® paste, 1.23% acidulated phosphate fluoride, or a temporary filling material for 24 h.30 extracted human non-carious third molars were utilized for the pulpal pressure experiment in which direct communication to the pulp chamber was created by cutting at a level approximately 1 mm below the cemento-enamel junction while the coronal enamel was ground to expose mid coronal dentin. The dentin surface was exposed to a simulated pulpal pressure. The dentin surfaces had BiominF® paste, an oxalate desensitizing agent, or temporary filling material followed by application of a universal adhesive system.ResultsOne way ANOVA showed that BiominF® paste remineralized effectively the demineralized enamel or dentin, did not affect the bond strength of the enamel and dentin surfaces to the tested adhesive system p < 0.05, and improved the acid resistance of the demineralized enamel and dentin against a secondary erosive challenge. Moreover, BiominF® paste decreased the nanoleakage expression in the dentin/adhesive interface exposed to a simulated pulpal pressure.SignificanceBiominF® paste may serve as a temporary filling material that may improve the longevity of adhesive restorations and help to conserve tooth structures by preserving the demineralized enamel and dentin form cutting during cavity preparation.  相似文献   
144.
Cytogenetic alterations, such as amplifications, deletions, or translocations, contribute to myeloid malignancies. MicroRNAs (miRNAs) have emerged as critical regulators of hematopoiesis, and their aberrant expression has been associated with leukemia. Genomic regions containing sequence alterations and fragile sites in cancers are enriched with miRNAs; however, the relevant miRNAs within these regions have not been evaluated on a global basis. Here, we investigated miRNAs relevant to acute myeloid leukemia (AML) by (1) mapping miRNAs within leukemia-associated genomic alterations in human AML cell lines by high-resolution genome arrays and (2) evaluating absolute expression of these miRNAs by massively parallel small RNA sequencing. Seventy-seven percent (542 of 706) of miRNAs mapped to leukemia-associated copy-number alterations in the cell lines; however, only 18% (99 of 542) of these miRNAs are expressed above background levels. As evidence that this subset of miRNAs is relevant to leukemia, we show that loss of 2 miRNAs identified in our analysis, miR-145 and miR-146a, results in leukemia in a mouse model. Small RNA sequencing identified 28 putative novel miRNAs, 18 of which map to leukemia-associated copy-number alterations. This detailed genomic and small RNA analysis points to a subset of miRNAs that may play a role in myeloid malignancies.  相似文献   
145.
In an era of rapidly expanding and evolving 3-dimensional echocardiographic (3DE) technology, 1 of the issues facing the 3DE quantification of chamber volumes and function is that different software vendors use different methodologies and algorithms. The aim of this study was to evaluate the comparability and reproducibility of 3DE direct volumetric and speckle-tracking methods for left ventricular (LV) and left atrial (LA) chamber quantification. A total of 120 subjects (mean age 53 ± 17 years, 65% men), including 88 unselected patients and 32 healthy volunteers, underwent 3DE acquisitions and analysis using direct volumetric and speckle-tracking methods successively. Measurements of LV and LA volumes and LV function were compared between the 2 3DE methods. Additionally, intraobserver and interobserver reproducibility was assessed in 40 randomly selected patients. Measurements of LV end-diastolic volume, end-systolic volume, and ejection fraction by 3DE direct volumetric and 3DE speckle-tracking methods were comparable, with good correlations (r = 0.98, r = 0.98, and r = 0.87, respectively), small biases, and narrow limits of agreement (-1 ± 8 ml, -1 ± 8 ml, and 0 ± 6%, respectively). For measurements of LA end-systolic volume and end-diastolic volume, similar correlations (r = 0.96 for both), small biases, and narrow limits of agreement (-2 ± 6 and -1 ± 5 ml, respectively) were found between the 2 methods. Intraobserver and interobserver reproducibility for LV and LA quantification were comparable for the 2 methods. In conclusion, 3DE direct volumetric and speckle-tracking methods give comparable and reproducible quantification of LV and LA volumes and function, making interchangeable application a viable option in daily clinical practice.  相似文献   
146.
Background and study aimsAuto-immune hepatitis (AIH) in children is a rare chronic progressive liver disorder. It is characterised serologically by high aminotransferase levels, elevated immunoglobulin G (IgG) and the presence of autoantibodies. AIH is divided into two types according to the autoantibody profile. This study aims to assess frequency, clinical manifestations, biochemical features and outcome of AIH in children attending Assuit University Hospitals in Upper Egypt with acute icteric hepatitis and seronegative viral markers (anti-hepatitis A virus (HAV) IgM, HbsAg, anti-hepatitis C virus (anti-HCV) Ab).Patients and methodsThe study includes 34 children with AIH, diagnosed on the basis of the International Scoring Criteria of Auto-immune Hepatitis, recruited from Assuit University Hospitals, during the period from January 2005 to December 2009. All patients received prednisolone 2 mg kg–1 day–1. Follow-up was done for 1 year.ResultsAmong 34 children diagnosed as AIH, 24 were females (70.5%) and 10 were males (29.5%). Jaundice represented the most consistent finding in all patients. According to the autoantibody profile, 25 children were classified as type 1 and nine children were classified as type 2. Corticosteroid therapy was started. Complete remission was observed in 67.6% of patients and partial remission in 17.6%. There was no significant statistical difference in clinical and biochemical features of AIH in patients regarding the response to treatment. Mild side effects of steroid therapy were encountered in 48.2% of patients. After complete withdrawal of corticosteroids, six patients (20.7%) developed relapse.ConclusionAIH type 1 was the main form of AIH in children referred to Assiut University Hospitals. Girls were more affected than boys. AIH type 1 exhibited a more active, ongoing immunologic process. Steroid alone can be used successfully in most cases. Children with AIH type 2 had a higher frequency of relapse after corticosteroid withdrawal. Further studies on a larger number of cases and long-term follow-up are recommended.  相似文献   
147.
CONTEXT: The insulinoma syndrome is marked by fasting hypoglycemia and inappropriate elevations of insulin. The gastrinoma syndrome is characterized by hypergastrinemia, ulcer disease, and/or diarrhea. Rarely, insulinoma and gastrinoma coexist in the same patient simultaneously. OBJECTIVE: Our objective was to determine the cause of a patient's hypoglycemic episodes and peptic ulcer disease. DESIGN AND SETTING: This is a clinical case report from the Clinical Research Center of the National Institutes of Health. PATIENT AND INTERVENTION: One patient with hypoglycemic episodes and peptic ulcer disease had a surgical resection of neuroendocrine tumor. RESULTS: The patient was found to have a single tumor cosecreting both insulin and gastrin. Resection of this single tumor was curative. CONCLUSIONS: A single pancreatic neuroendocrine tumor may lead to the expression of both the hyperinsulinemic and hypergastrinemic syndromes.  相似文献   
148.
Various studies have identified a critical role for Notch signaling in cardiovascular development. In this and other systems, Notch receptors and ligands are expressed in regions that undergo epithelial-to-mesenchymal transformation. However, there is no direct evidence that Notch activation can induce mesenchymal transdifferentiation. In this study we show that Notch activation in endothelial cells results in morphological, phenotypic, and functional changes consistent with mesenchymal transformation. These changes include downregulation of endothelial markers (vascular endothelial [VE]-cadherin, Tie1, Tie2, platelet-endothelial cell adhesion molecule-1, and endothelial NO synthase), upregulation of mesenchymal markers (alpha-smooth muscle actin, fibronectin, and platelet-derived growth factor receptors), and migration toward platelet-derived growth factor-BB. Notch-induced endothelial-to-mesenchymal transformation does not seem to require external regulation and is restricted to cells expressing activated Notch. Jagged1 stimulation of endothelial cells induces a similar mesenchymal transformation, and Jagged1, Notch1, and Notch4 are expressed in the ventricular outflow tract during stages of endocardial cushion formation. This is the first evidence that Jagged1-Notch interactions induce endothelial-to-mesenchymal transformation, and our findings suggest that Notch signaling may be required for proper endocardial cushion differentiation and/or vascular smooth muscle cell development.  相似文献   
149.
CD36 and LIMPII analog 1, CLA-1, and its splicing variant, CLA-2 (SR-BI and SR-BII in rodents), are human high density lipoprotein receptors with an identical extracellular domain which binds a spectrum of ligands including bacterial cell wall components. In this study, CLA-1- and CLA-2-stably transfected HeLa and HEK293 cells demonstrated several-fold increases in the uptake of various bacteria over mock-transfected cells. All bacteria tested, including both Gram-negatives (Escherichia coli K12, K1 and Salmonella typhimurium) and Gram-positives (Staphylococcus aureus and Listeria monocytogenes), demonstrated various degrees of lower uptake in control cells. This result is consistent with the presence of high-density lipoprotein-receptor-independent bacterial uptake that is enhanced by CLA-1/CLA-2 overexpression. Bacterial lipopolysaccharides, lipoteichoic acid, and synthetic amphipathic helical peptides (L-37pA and D-37pA) competed with E. coli K12 for CLA-1 and CLA-2 binding. Transmission electron microscopy and confocal microscopy revealed cytosolic accumulation of bacteria in CLA-1/CLA-2-overexpressing HeLa cells. The antibiotic protection assay confirmed that E. coli K12 was able to survive and replicate intracellularly in CLA-1- and CLA-2-overexpressing HeLa, but both L-37pA and D-37pA prevented E. coli K12 invasion. Peritoneal macrophages isolated from SR-BI/BII-knockout mice demonstrated a 30% decrease in bacterial uptake when compared with macrophages from normal mice. Knockout macrophages were also characterized by decreased bacterial cytosolic invasion, ubiquitination, and proteasome mobilization while retaining bacterial lysosomal accumulation. These results indicate that, by facilitating bacterial adhesion and cytosolic invasion, CLA-1 and CLA-2 may play an important role in infection and sepsis.  相似文献   
150.
Nonsteroidal anti-inflammatory drugs are a frequent cause of gastric and duodenal mucosal injury. We examined the effect of indomethacin on duodenal mucosal bicarbonate secretion and prostaglandin output in healthy subjects. Subjects received either 50 mg of indomethacin or placebo orally 13 hours and 1 hour before study. A 4-cm segment of proximal (the duodenal bulb) or distal (10 to 14 cm beyond the pylorus) duodenum was isolated and perfused with 154 mM NaCl containing a nonabsorbable marker. In the proximal duodenum indomethacin reduced both basal and acid-stimulated bicarbonate secretion by approximately 65% (p less than 0.01); in the distal duodenum indomethacin decreased basal and acid-stimulated bicarbonate output by approximately 45% (p less than 0.01). Oral indomethacin inhibited basal and acid-stimulated duodenal prostaglandin E2 output in both the proximal and distal duodenum. We conclude that, by decreasing duodenal mucosal bicarbonate production and prostaglandin output in humans, oral indomethacin, in two doses of 50 mg each, impairs an important duodenal defense mechanism.  相似文献   
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