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991.
Direct anatomical-MRI correlation: the knee   总被引:2,自引:0,他引:2  
Summary Cadaveric material is often used to guide and validate the interpretation of magnetic resonance imaging (MRI) studies. Direct correlation is achieved when the cadaver material is imaged and then directly sectioned in the plane of the image. Indirect correlation, where the cadaveric sections are compared with unrelated in-vivo images, is easier and more commonly used. Technical difficulties associated with the direct method include preservation of form and composition of the tissues, and the choice of the correct location and plane in which to section the cadaver. Using an MRI compatible ruler, designed to assist the direct correlation of MRI and cadaveric sections, we have examined 10 preserved (embalmed) cadaveric knees using different MRI sequences on several occasions. Despite these variations, subsequent sectioning of the cadaveric knees has shown good correlation with the MR images. Of 54 MR images compared with cadaveric sections, anatomical correlation was rated by independent observers as good or perfect in 47 (87%). This new, versatile and simple method can make better use of our preserved human cadaveric material and has potentially wide application; we are now developing it further to assess the technical capabilities of novel imaging sequences.
Corrélation directe entre anatomie et IRM du genou
Résumé Pour guider ou valider une interprétation d'examens IRM, on a souvent recours au cadavre. On obtient une corrélation directe par confrontation de la coupe IRM d'une pièce avec la coupe anatomique faite dans le même plan. Une autre méthode plus facile et plus usuelle dite de corrélation indirecte est celle où une coupe IRM prise sur le vif est comparée avec des coupes sur le cadavre sans rapport direct. Elle ne présente pas les difficultés techniques d'une corrélation directe, qui requiert d'une part la préservation de forme et de la composition des tissus, et d'autre part l'exactitude du plan de coupe sur le cadavre qui doit coïncider avec la coupe IRM. Une règle IRM-compatible, conçue pour réaliser cette corrélation directe, a permis l'étude de 10 genoux de sujets embaumés, avec des séquences différentes d'IRM, à plusieurs reprises. En dépit des variations, la corrélation s'avère satisfaisante. Sur 54 coupes IRM soumises à cette corrélation, la corrélation est bonne ou parfaite pour 47 d'entre elles selon des observateurs differents, soit pour 87% des coupes. Cette méthode nouvelle, souple et simple, permet de tirer le meilleur usage du matériel humain conservé, avec un champ d'applications potentielles large. Nous sommes en train de la développer davantage pour l'évaluation des capacités techniques de nouvelles séquences d'image.
  相似文献   
992.
A case of acute myelomonocytic leukaemia (AMMOL) is reported in which skin infiltration with xanthomatous nodules was the presenting feature. The histological, including ultrastructural, appearances are described.  相似文献   
993.
Introduction: Membranous nephropathy (MN) is the most common cause of a nephrotic syndrome in Caucasian adults. The identification of target antigens in MN in the last decade has had a major impact on the clinical approach to these patients.

Areas covered: Since the discoveries in animal models in the 1980s that circulating autoantibodies induce disease upon in situ binding to glomerular podocytes, many attempts have been undertaken to define the human antigens responsible for disease induction. Only in 2009 was Phospholipase A2 Receptor 1 described as the major antigen responsible for MN onset in about 70% of patients. Subsequently, in 2014, Thrombospondin Type-1 Domain-Containing 7A was identified as a second antigen, accounting for 2–3% of patients with MN. The knowledge of the role of these antibodies in MN has improved the diagnosis and management of patients and helped to better define the need for immunosuppressive treatment.

Expert commentary: These discoveries over the last 10 years in the discipline of nephrology have clearly shown the improvements a better understanding of disease pathogenesis can bring for patient care.  相似文献   

994.
Two successful pregnancies in a 46,XY patient   总被引:1,自引:0,他引:1  
Two successful pregnancies (singleton followed by twins) following ovum donation/in-vitro fertilization in a 46,XY woman have been studied. Although similar cases have previously been presented: in a pure XY patient and in a 45,X/46,XY patient, this case is one in which a subsequent successful pregnancy has resulted. In such patients, the rate of Caesarean section appears to be increased, and we postulate that the hypoplastic nature of the uterus, although able to respond quite well to both exogenous and endogenous hormones to accept and maintain a pregnancy, may lack the capability to respond fully in labour by dilating appropriately.   相似文献   
995.
996.

Background

Renal transplantation is the treatment modality of choice for patients with end stage kidney failure. We present our experience of graft and patient survival of initial 500 renal transplants performed between May 1991 and July 2006, at Army Hospital (R&R).

Material and Methods

All patients received triple drug immunosuppression with cyclosporine/tacrolimus, azathioprine/ mycophenolate mofetil and steroids. Patients in high risk group received induction therapy with IL-2 receptor blockers/anti-thymocyte globulin.

Results

Majority of the recipients (79%) were males, whereas majority of the donors (59.4%) were females. In the donor profile, 385 (77%) transplants were live related, 108 (21.6 %) were spousal and 7 (1.4%) were cadaveric transplants. Mean age of the donors and recipients was 42.11 ± 11.53 years (range 19–72 years) and 33 ± 9.39 years (range 5–60 years) respectively. Eighty two patients (16.4%) were lost to follow up and the present data on rejections, patients and graft survival pertains to 418 patients. These patients have been followed up for a mean period of 2.63 years (SE, 0.122; median 1.8 years; range 0–13.36 years). Acute rejection episodes occurred in 115 (27.3%) patients and 95% of these could be reversed with steroids/ATG. Sixty eight patients (16%) have died on follow-up. Our one-year, 5 year and 10 year estimated graft survival is 95.4% (SE, 0.01), 80.5% (SE, 0.03) and 53.1% (SE, 0.09) respectively and patient survival at one year is 93.2% (SE, 0.01). The estimated graft and patient survival in our series is 9.83 (95% CI, 8.92–10.73) and 9.80 (8.93–10.67) years respectively.

Conclusion

This centre''s short-term graft survival of 95.4% is comparable to the best centres of the world.Key Words: Kidney transplant, Graft survival, Patient survival  相似文献   
997.

Background

Labour pain can be deleterious for mother and baby. Epidural analgesia relieves labour pains effectively with minimal maternal and foetal side effects. A prospective open label study was undertaken to ascertain effective dosing regime for walking epidural in labour.

Methods

Fifty women with singleton foetus in vertex position were included. Epidural catheter was inserted in L2-3 / L3-4 interspinous space. Initial bolus of 10 ml (0.1% bupivacaine and 0.0002% fentanyl) solution was injected and after the efficacy of block was established, an epidural infusion of the same drug solution was started at the rate of 5 ml/hour.

Results

In first stage of labour 80% of the parturient had excellent to good pain relief (visual analogue scale 1 to 3) with standard protocol while 20% parturient required one or more additional boluses. For the second stage, pain relief was good to fair (VAS 4-6) for most of the parturient. The incidence of caesarian section was 4% and 6% needed assisted delivery. No major side effects were observed.

Conclusion

0.1% bupivacaine with 0.0002% fentanyl maximizes labour pain relief and minimizes side effects.Key Words: Labour analgesia, Walking epidural  相似文献   
998.

Background

Polymerase chain reaction (PCR) is useful for rapid microbial detection in body fluids with low microbial load. It is easier to use universal or broad range primers for the amplification of conserved stretches of DNA common to all bacteria like 16S rRNA gene, followed by restriction fragment length polymorphism (RFLP) of PCR products.

Methods

Forty samples of cerebrospinal fluid were collected. After DNA extraction, universal or broad range PCR was performed using two universal primers U1-5''-CCAGCAGCCGCGGTAATACG-3'', corresponding to nucleotides 518 to 537 of the Escherichia coli 16S rRNA gene, and U2 − 5''-ATCGG(C/T)TACCTTGTTACGACTTC-3'', corresponding to nucleotides 1513 to 1491 of the same gene. The PCR product was subjected to digestion by endonucleases- HaeIII, Mn11, BstB1 and Alu1. Restriction pattern obtained was compared with that of standard organisms to identify the pathogen. The results were compared with conventional methods.

Result

Universal PCR could detect pathogens in 20% samples within 13-18 hours as compared to 16% by conventional methods. The analytical sensitivity was 10 Gram negative and 250 Gram positive organisms per 200 μl sample. Overall sensitivity was 83.3% and specificity was 91.2%.

Conclusion

Universal PCR followed by RFLP of PCR product is a good alternative to conventional diagnosis of bacterial pathogens.Key Words: Body fluids, Polymerase chain reaction, Restriction fragment length polymorphism  相似文献   
999.
Background: The Amplatzer perimembranous ventricular septal occluder is an innovative device for percutaneous closure of perimembranous ventricular septal defects (PMVSD). In appropriately selected cases this procedure is safe and effective.  相似文献   
1000.
PURPOSE: Copper in serum supports angiogenesis and inhibits replication of wild-type HSV-1. Copper chelation is currently being investigated as an antiangiogenic and antineoplastic agent in patients diagnosed with cancer. Herpes simplex virus-derived oncolytic viruses (oHSV) are being evaluated for safety and efficacy in patients, but several host barriers limit their efficacy. Here, we tested whether copper inhibits oHSV infection and replication and whether copper chelation would augment therapeutic efficacy of oHSV. EXPERIMENTAL DESIGN: Subcutaneous and intracranial tumor-bearing mice were treated with oHSV ± ATN-224 to evaluate tumor burden and survival. Virus replication and cell killing was measured in the presence or absence of the copper chelating agent ATN-224 and in the presence or absence of copper in vitro. Microvessel density and changes in perfusion were evaluated by immunohistochemistry and dynamic contrast enhanced MRI (DCE-MRI). Serum stability of oHSV was measured in mice fed with ATN-224. Tumor-bearing mice were injected intravenously with oHSV; tumor burden and amount of virus in tumor tissue were evaluated. RESULTS: Combination of systemic ATN-224 and oHSV significantly reduced tumor growth and prolonged animal survival. Immunohistochemistry and DCE-MRI imaging confirmed that ATN-224 reduced oHSV-induced blood vessel density and vascular leakage. Copper at physiologically relevant concentrations inhibited oHSV replication and glioma cell killing, and this effect was rescued by ATN-224. ATN-224 increased serum stability of oHSV and enhanced the efficacy of systemic delivery. CONCLUSION: This study shows that combining ATN-224 with oHSV significantly increased serum stability of oHSV and greatly enhanced its replication and antitumor efficacy. Clin Cancer Res; 18(18); 4931-41. ?2012 AACR.  相似文献   
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