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71.
Medical trainees face substantial financial and scheduling burdens during the interview process at various levels of training. With current social distancing and travel restrictions in place, in‐person interviews now carry an additional health risk that make it difficult for training programs and applicants to conduct a thorough interview process. Virtual interviews and presentations are some of the technology‐driven solutions that have been accelerated in the current social context to mitigate financial burdens and health risks. By utilizing immersive technology to provide virtual tours of training sites, applicants have the opportunity to gain a comprehensive perspective before making the critical decision of where to continue their training. We provide our experiences with creating a 360‐degree virtual tour of our children's hospital and the methods for distribution to pediatric anesthesia fellowship applicants. Moving forward, training programs may consider immersive virtual tours as an alternative to face‐to‐face site visits to not only help alleviate the financial and scheduling burden for applicants but also to protect the well‐being of healthcare personnel and patients in the context of a global pandemic.  相似文献   
72.
Background.Improper positioning of central venous catheters (CVCs) can lead to erosion through the superior vena cava (SVC) or right atrium (RA) and pericardial tamponade. It is widely recommended that the tip of CVCs be placed above the heart or the pericardial reflection. The purpose of this study was to identify an easily recognized landmark to allow identification of the proximal extent of the pericardial reflection on a routine chest radiograph (CXR). Methods.We analyzed the computerized tomograms of the chest from 97 adults to evaluate the relationship between the pericardial reflection, SVC, carina, and right mainstem bronchus. Correlations between demographic data and length of SVC or pericardial reflection were sought. Results.The mean length of the SVC was 6.5 cm. The pericardial reflection covered an average of 3.6 cm of the distal SVC. The carina was a mean of 1.3 cm below the mid-point of the SVC and 0.7 cm below the pericardial reflection. There was no significant correlation between SVC or pericardial length and either age, height, or weight. Conclusions.The distal half of the SVC lies within the pericardial reflection, and the upper limit of the pericardial reflection is slightly above the level of the carina. These landmarks are useful for determining proper position of the tip of a CVC on CXR.  相似文献   
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Background: Most children in need of cardiac pacemakers remain dependent on the function of the permanent from childhood to adulthood. We sought to evaluate and compare the function between epicardial and endocardial pacemakers in pediatric groups with different conditions. Methods: Between 2012 and 2018, this single-canter study evaluated 44 pediatric patients with indications for epicardial or endocardial pacemakers. Results: The 2 groups, at a median age of 5 (0.1–16) years, were compared concerning the characteristics of the leads used (n = 80: bipolar, unipolar, steroid-eluting, and non–steroid-eluting), survival data, and complications. The reason for pacemaker implantation was congenital complete heart block in 11 (25%) cases and postoperative heart block in 33 (75%) cases. The commonest congenital heart disease accompanied by postoperative block was the ventricular septal defect. In the endocardial lead group, the mean ventricular pacing threshold immediately after the implantation and during the follow-up was less than that in the epicardial lead group (0.75 vs. 0.81 V; P = 0.01 and 0.8 vs. 2.4 V; P = 0.001). During the follow-up, the mean battery longevity was better in the endocardial group (last visit: 6.7 endocardial vs. 3.3 years epicardial). Lead failure was commoner in the epicardial pacemaker, and chronic high-pacing threshold pattern was seen in 14 patients in this group. After 3 years, freedom from lead failure was 94% and 63% in the endocardial and epicardial leads. Conclusions: Pacemakers with endocardial bipolar steroid-eluting leads showed better lead characteristics regarding survival and battery longevity than epicardial pacemakers without these lead characteristics. An appropriate pacemaker type should be selected based on the patient’s condition.  相似文献   
76.
Recombinant adenoviral mediated delivery of suicide and cytokine genes has been investigated as a treatment for hepatic metastases of colon carcinoma in mice. Liver tumors were established by intrahepatic implantation of a poorly immunogenic colon carcinoma cell line (MCA-26), which is syngeneic in BALB/c mice. Intratumoral transfer of the herpes simplex virus type 1 thymidine kinase (HSV-tk) and the murine interleukin (mIL)-2 genes resulted in substantial hepatic tumor regression, induced an effective systemic antitumoral immunity in the host and prolonged the median survival time of the treated animals from 22 to 35 days. The antitumoral immunity declined gradually, which led to tumor recurrence over time. A recombinant adenovirus expressing the mIL-12 gene was constructed and tested in the MCA-26 tumor model. Intratumoral administration of this cytokine vector alone increased significantly survival time of the animals with 25% of the treated animals still living over 70 days. These data indicate that local expression of IL-12 may also be an attractive treatment strategy for metastatic colon carcinoma.  相似文献   
77.
Invasive mycoses represent a rare but severe complication following hemopoietic SCT (HSCT) in children. Their incidence is related to the type of donor, being higher after allogeneic transplant, especially from alternative donors. Moreover, the incidence of invasive mycoses varies in the different post transplant phases. Neutropenia, lymphopenia, GvHD, high-dose steroids or other immunosuppressive drugs represent well-known risk factors. The clinical features of invasive mycoses after HSCT in children are similar to those observed in adults, and the diagnostic tools, including Aspergillus galactomannan antigen detection, are feasible also in pediatrics. Mortality due to invasive mycoses after HSCT in children is high.  相似文献   
78.
MitraClip therapy for Mitral Regurgitation(MR) in advanced-endstage heart failure(HF),could open a final bridge to improve symptoms and quality of life in \"not transplantable\" patients. We describe a homeless patient with NYHA class III HF, not elegible to heart transplantation for poor socio-economic status,and severe functional MR,treated with MitraClip. The patient was not suitable for conventional mitral valve repair because of high surgical risk and advanced HF (The STS mortality morbidity score=76%; EUROSCORE II=9,7%). Severe MR was confirmed at TEE preoperative evaluation of patient in which severe LV systolic dysfunction, diastolic dysfunction, severe right ventricle dysfunction, moderate tricuspid regurgitation and post-capillary pulmonary hypertension were detected. After 2 MitraClips implantation, TEE documented effective device position in relation to the main regurgitant jet, a MR grade reduction to 2 , with uneventful recovery. A gradual hemodynamic and general improvement was observed at three-month follow-up echocardiography documenting PAPs reduction and LVEF improvement. Beside, the patient showed HF symptoms reduction in NYHA class I-II. Management of functional MR in end-stage HF is an hard challenge, in addiction to the limited patient group feasibility and long-waiting list of heart transplantation. In the setting of this difficult current real-world experience, percutaneous tecnique was able to improve general conditions, quality of life and survival of our referred patient.  相似文献   
79.
Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region. The single point mutation 845A, changing cysteine at position 282 to tyrosine (C282Y), in this gene has been identified as the main genetic basis of hereditary hemochromatosis. Two other mutations, 187G, a histidine to aspartate at amino acid 63 (H63D), and 193T, a serine to cysteine at amino acid 65 (S65C), appear to be associated with milder forms of hereditary hemochromatosis. There is a high prevalence of the C282Y mutation in northern European populations, whereas in those of the Mediterranean basin the prevalence seems low and almost absent in Far East countries. This mutation seems usually to occur on the ancestral haplotype 7.1. Accordingly, a Celtic origin of this mutation has been suggested. The aim of this study was to determine the frequency of HFE gene mutations in five geographic regions in Italy. Samples were tested for C282Y, H63D, and S65C mutations of the HFE gene according to methods of each laboratory and the results were standardized with the exchange of typed samples between the different laboratories. In addition, C282Y-positive DNA samples were typed for D6S105 allele 8 and HLA-A3 by ARMS-PCR. We have found that the allele frequency of the C282Y mutation decreases from northeast Italy (Friuli, 6%) to northwest Italy (Piedmont, 4.8%) and to central Italy (Emilia-Romagna, 1.7%). However, this mutation is lacking in the two regions of the Mediterranean basin's center (Sicily and Sardinia). Accordingly, a significant difference in the frequency of the mutation was observed between these Italian regions (P = 0.07 x 10(-3)). In contrast, no difference was observed in allele frequency of H63D in the five Italian regions. Finally, as regards the S65C mutation a very low frequency was observed in Friuli, Emilia-Romagna, and Sardinia, whereas in Sicily and Piedmont we have not found this mutation. In conclusion, these data are consistent with the hypothesis that the C282Y mutation occurred in Caucasian populations of Celtic origin, whereas the H63D mutation is more ancient as demonstrated by the ubiquitous distribution.  相似文献   
80.
Myocardial disarray. A critical review.   总被引:1,自引:3,他引:1       下载免费PDF全文
Myocardial disarray or disorganisation is at present a contentious topic, not least because its value as a clinical marker for hypertrophic cardiomyopathy has changed considerably over the years. Initially observed as one of the features of asymmetric septal hypertrophy, disarray has since been promoted as its pathognomonic histological feature, regarded by some observers as the morphological manifestation of a genetically transmitted myocardial defect. Recently, however, it has become evident that myocardial disarray is not limited to hypertrophic cardiomyopathy, but is encountered in hearts with both congenital and acquired conditions, and is also observed in normal hearts. The specificity of disarray for hypertrophic cardiomyopathy is thus seriously questioned. Latterly, it has been suggested that disarray, judged from through-and-through sections of the ventricular midseptum is a highly specific and sensitive marker of hypertrophic cardiomyopathy when considered in quantitative rather than qualitative fashion. The present study sets out to answer the question whether disarray could be the histological expression of the normal but intricate fibre architecture of the heart, a consideration also initiated by debatable definitions of normality and abnormality of myocardial histology. Gross fibre dissections in five normal hearts showed that many sites occurred in which disarray was a natural phenomenon. In five more hearts it was found that the plane of section of a tissue block might profoundly influence the histology. In fact, tissue cubicles sampled from different faces showed a change in histology in the vast majority. Thus the diagnostic significance of myocardial disarray as a marker of hypertrophic cardiomyopathy in the clinical setting almost vanishes; a change in orientation of a tissue section may actually turn "normality" into "disarray".  相似文献   
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