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31.

Objectives

Systemic sclerosis heart involvement (SHI) is one of systemic sclerosis (SSc) most frequent complications, both in diffuse (dcSSc) and limited (lcSSc) cutaneous forms of disease. Nowadays, SHI is a major factor decreasing SSc survival rate because, when clinically evident, is associated with 70% of mortality at 5 years. SHI shows different forms, primary and/or secondary. Primary myocardial SHI is characterized by fibrosis. Aim of our study is to assess the presence and pattern of fibrosis as detected by cardiac magnetic resonance (CMR) in systemic sclerosis.

Methods

In this study, we used CE-MRI (contrast enhanced-MRI) in 58 female SSc patients. Images were evaluated to obtain functional parameters and to see presence, location and pattern (nodular, linear or diffuse) of myocardial LE, sign of fibrosis. CE-MRI findings were correlated with patients clinical setting.

Results

Myocardial fibrosis was detected in 25 of 58 patients (43%). The main finding observed in 16 of these 25 patients was a late enhancement showing a linear pattern, without coronary distribution and sparing the sub-endocardial myocardial layers. A patchy nodular enhancement pattern was observed in 9 patients (36%). Patients with linear pattern presented dcSSc, on the contrary patients with nodular LE displayed the lcSSc form.

Conclusions

This study shows that CE-MRI is a reliable technique to detect SHI earlier than other methods. SHI increase passive myocardial stiffness, proportional to collagen deposition degree, leading to cardiac remodelling with possible development of heart failure, even with normal ejection fraction. An early treatment of SHI might improve SSc patients outcome.  相似文献   
32.
OBJECTIVE: The purpose of this study was to determine the rate of progression of midventricular obstruction in adolescents and adults with double-chambered right ventricle. METHODS: Clinical and echocardiographic findings in 45 patients (mean age 26 +/- 6 years, range 15-44) diagnosed with double-chambered right ventricle were retrospectively analyzed. Twenty patients underwent surgical repair before the age of 15 years. The relationship between Doppler midventricular pressure gradient and patient age was analyzed in 25 patients without previous repair. Sequential change in midventricular obstruction was determined for patients with 2 or more Doppler echocardiographic examinations performed within at least a 2-year interval. RESULTS: Right midventricular pressure gradient in nonrepaired patients was 70 +/- 38 mm Hg (range 25-150). A significant relationship between midventricular obstruction and patient age (r = 0.64, P <.001) was found. Midventricular pressure gradient at initial evaluation was 32 +/- 27 mm Hg in 16 patients < 25 years and 73 +/- 45 mm Hg in 9 patients >/= 25 years (P <.03). After the initial study, 5 patients underwent surgical repair and 13 patients without repair were followed up for a period of 6.1 +/- 2.7 years (range 2-9), in which midventricular pressure gradient increased from 32 +/- 26 mm Hg to 67 +/- 35 mm Hg (P <.001). The slope of the change in midventricular pressure gradient was 6.2 +/- 3 mm Hg per year of follow-up. Seven more patients underwent surgical repair during follow-up due to progression of the obstruction. There was no mortality nor residual midventricular obstruction in surgically repaired patients. CONCLUSIONS: Mild right midventricular obstruction shows a fast rate of progression in adolescents and young adults. Thus, close clinical and echocardiographic follow-up is advised, and surgical repair should be considered if significant progression of obstruction is detected.  相似文献   
33.
BACKGROUND: For cyclosporine (CsA), 2-hr postdose level (C2) is the best single time point predictor of the area under the curve and a critical measure for effective dosing. The therapeutic CsA microemulsion (Neoral) C2 range in de novo heart transplant patients remains to be determined. PURPOSE: The purpose of this study was to determine the efficacy of CsA C2 monitoring in de novo heart transplant patients receiving basiliximab induction. METHODS: This prospective, multicenter, randomized study enrolled 87 adult heart transplant recipients stratified according to 4 to 6 hrs posttransplant serum creatinine less than or equal to 170 micromol/L (cohort A) or more than 170 micromol/L (cohort B). Patients in cohort A were randomized into three C2 ranges (A1: "high" n=25, 1600-1800 ng/mL; A2: "intermediate" n=27, 1400-1600 ng/mL; and A3: "low" n=24, 1200-1400 ng/mL). Patients in cohort B were randomized into intermediate (n=5) and low C2 (n=6). Target ranges were progressively lowered after 1 month. Immunosuppression included basiliximab, Neoral, mycophenolate mofetil, and corticosteroids. Endpoints were acute rejection and renal function. RESULTS: The incidence of acute rejection at 12 months was 44% in group A1, 41% in group A2, 33% in group A3, and 27% in cohort B. Pretransplant and 12-month creatinine clearance (mL/min) were group A1, 72+/-25 and 64+/-24; group A2, 81+/-32 and 68+/-25; group A3, 91+/-28 and 86+/-26; and cohort B, 62+/-28 and 79+/-37. CONCLUSION: These results suggest that C2 monitoring is safe in de novo heart transplant patients. A low Neoral C2 range in combination with basiliximab induction resulted in preserved renal function without increased risk of acute rejection.  相似文献   
34.
Ganciclovir (GCV) prophylaxis or pre-emptive therapy significantly reduce the rate of cytomegalovirus (CMV) disease and viremia, but increase the potential for emergence of ganciclovir-resistant CMV strains. The inhibitor concentration at 50% (IC(50)) of GCV from 156 CMV isolates from 59 renal or heart transplant recipients was calculated by means of a rapid phenotypic susceptibility assay. Twenty-seven strains were from 14 patients undergoing GCV therapy. The IC(50) was higher in patients under the prophylaxis regimen. One CMV strain, from a heart transplant recipient, became GCV-resistant after 1 month of therapy (IC(50)=13.7 micromol/l). These data, together with clinical and virological markers, suggested that a switch to foscarnet was necessary, and good evolution was observed. Thus, assay of CMV susceptibility to GCV could be helpful in clinical management.  相似文献   
35.
36.
BACKGROUND: There is no standard triage method for earthquake victims with crush injuries because of a scarcity of epidemiologic and quantitative data. We conducted a retrospective cohort study to develop predictive models based on clinical data for crush injury in the Kobe earthquake. METHODS: The medical records of 372 patients with crush injuries from the Kobe earthquake were retrospectively analyzed. Twenty-one risk factors were assessed with logistic regression analysis for three outcomes relating to crush syndrome. Two types of predictive triage models--initial evaluation in the field and secondary assessment at the hospital--were developed using logistic regression analysis. Classification accuracy, Brier score and area under the receiver operating characteristic curve (AUC) were used to evaluate the model. RESULTS: The initial triage model, which includes pulse rate, delayed rescue, and abnormal urine color, has an AUC of 0.73. The secondary model, which includes WBC, tachycardia, abnormal urine color, and hyperkalemia, shows an AUC of 0.76. CONCLUSIONS: These triage models may be especially useful to nondisaster experts for distinguishing earthquake victims at high risk of severe crush syndrome from those at lower risk. Application of the model may allow relief workers to better utilize limited medical and transportation resources in the aftermath of a disaster.  相似文献   
37.
38.
To describe the morphology of the proximal femoral epiphysis in a rabbit model from the ischemic insult to the end of the revascularization process. Ischemia of the femoral head was induced in 32 rabbits at the 8th day of life, by sectioning the joint capsule and the ligamentum teres and dislocating the femoral head. Rabbits were sacrificed at 4, 8, 12, 18, 21, 26, 34, and 48 days after surgery and femoral heads were observed histologically. During the first days following the ischemic injury, large areas underwent necrotic changes. Both epiphyseal and physeal cartilage were thicker than normal and less trabecular bone formation was evident. Bone marrow was also diffusely necrotic within the secondary center of ossification. After day 12th, reparative process started with formation of extensive areas of fibrocartilage and several secondary centers of ossifications. At that stage femoral head deformity was already evident. In the following days the secondary centers of ossification cohalesced and epiphyseal and physeal cartilage resumed a normal appearance, but the femur showed a permanent deformity. In newborn rabbits, the ischemic injury to the femoral head blocked the ossification of the epiphyseal and physeal cartilage associated to necrotic bone marrow within the secondary center of ossification of the femoral head as well as to extensive areas of necrosis of epiphyseal and physeal cartilage. Extensive areas of fibrocartilage and small newly formed ossification centers within the femoral epiphysis were the results of the revascularization process, and femoral head deformity became stable afterward. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:535–541, 2015.  相似文献   
39.
40.
BackgroundSuccessful trauma resuscitation relies on multi-disciplinary collaboration. In most academic programs, general surgery (GS) and emergency medicine (EM) residents rarely train together before functioning as a team.MethodsIn our Multi-Disciplinary Trauma Evaluation and Management Simulation (MD-TEAMS), EM and GS residents completed manikin-based trauma scenarios and were evaluated on resuscitation and communication skills. Residents were surveyed on confidence surrounding training objectives.ResultsResidents showed improved confidence running trauma scenarios in multi-disciplinary teams. Residents received lower communication scores from same-discipline vs cross-discipline faculty. EM residents scored higher in evaluation and planning domains; GS residents scored higher in action processes; groups scored equally in team management. Strong correlation existed between team leader communication and resuscitative skill completion.ConclusionMD-TEAMS demonstrated correlation between communication and resuscitation checklist item completion and communication differences by resident specialty. In the future, we plan to evaluate training-related resident behavior changes and specialty-specific communication differences by residents.  相似文献   
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