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1.
A uniform policy for regionalization of ST-segment elevation myocardial infarction (STEMI) care raises several concerns. Transferring all STEMI patients to obtain primary percutaneous coronary intervention (PCI) may be less effective than transferring only high-risk STEMI patients. Delays in time to treatment >60 min associated with transferring patients for primary PCI may result in increased mortality for the average patient as compared with providing immediate fibrinolytic therapy at their initial hospital; yet more than 95% of patients transferred for primary PCI in the U.S. exceed this 60-min benchmark. Superior outcomes associated with treatment at higher-volume regional STEMI centers are inconsistent among centers, and there is no direct evidence that patients will benefit by a transfer to a high-volume hospital from a low-volume hospital. Published data suggest as many as 800 PCI patients would need to be transferred to a high-volume PCI hospital to avoid a single death at a low-volume PCI hospital. Although European randomized trial data suggest transferring patients with STEMI for primary PCI may be superior to immediate fibrinolytic therapy, these findings are unlikely to generalize to the U.S. health care system given size, geography, and organization. ST segment elevation myocardial infarction care regionalization would require a massive redistribution of health care resources, depriving several hospitals of advanced cardiac care facilities, expertise, and associated revenue. Clearer evidence of the benefits and discussion of potential harms are needed before adopting a national STEMI regionalization policy.  相似文献   
2.
A case of nontraumatic rupture of the ureter secondary to a nonopaque calculus is presented. Because of the inherent high image contrast caused by the leak of technetium 99m-DTPA-labeled urine, the technetium 99m DTPA excretory urogram is seen as an alternative to the intravenous urogram or contrast-enhanced computed tomography in selected cases of suspected ureteral rupture.  相似文献   
3.
Digitoxigenin alpha-L-, beta-L-, alpha-D-, and beta-D-glucosides; alpha-L-, beta-L-, alpha-D-, and beta-D-mannosides; and alpha-L- and beta-L-rhamnosides were stereoselectively synthesized from the corresponding sugar tetrabenzyl trichloroacetimidates. The Na+,K+-ATPase receptor inhibitory activities of these glycosides (as a measure of receptor binding) were compared with those of digitoxigenin, digitoxigenin 6'-hydroxy-beta-D-digitoxoside, digitoxigenin beta-D-galactoside, and digitoxigenin beta-D-digitoxoside. The observed activities reveal that a given sugar substituent may have a role in binding of some glycoside stereoisomers, but not others. With alpha-L- and possibly beta-L-rhamnosides, the 5'-CH3 and 4'-OH appear to have a predominant role in binding to the Na+,K+-ATPase receptor. Addition of a 6'-OH to form the corresponding mannosides dramatically disrupts the effect of both the 5'-CH3 and 4'-OH in prompting receptor binding of the alpha-L isomer. However, with the beta-L isomer, some influence of 4'-OH, 3'-OH, and 2'-OH binding remains. With beta-D-glycosides, binding via the "5'-CH3 site" appears to be of little importance and addition of a 6'-OH diminishes activity only slightly. With these beta-D-glycosides, an equatorial 4'-OH, axial 3'-OH, and equatorial 2'-OH groups appear to contribute to binding.  相似文献   
4.
The trafficking or homing of different lymphoid subsets to particular microenvironment is mediated by specific cell adhesion molecules (CAMs) expressed on lymphocytes and endothelial cells. B-cell chronic lymphocytic leukaemia (B-CLL) or Non-Hodgkin's lymphoma of small lymphocytic, B-cell type are monoclonal expansions of mature lymphocytes. The relative distribution of the tumor lymphocytes among various lymphoid compartments vary from patient to patient. Very few studies underlying this issue are available. To this effect, we have analysed the expression of LFA-1; VLA-4, ICAM-1; CD44H and CD44v6 (haematopoietic and variant form respectively) on freshly isolated lymphocytes obtained from bone marrow (BM), peripheral blood (PB) and lymph node (LN) by flow cytometry. Overall, we find strong expression of CD44H, low to moderate expression of LFA-1, negative to low expression of VLA-4 and lack of expression of CD44v6. ICAM-1 expression was observed only in patients with prominent lymphadenopathy. Higher expression of CD44H in PB lymphoid cells relative to that of BM lymphoid cells correlated with higher PB lymphocytosis (p < 0.001). Proliferating cell nuclear antigen expression in LN sections correlated inversely with VLA-4 expression on BM and PB lymphoid cells (p < 0.05). There was no significant correlation between expression of CAMs and bcl-2 protein.  相似文献   
5.
CONTEXT: Although protease inhibitors are used routinely in adults with human immunodeficiency virus (HIV) infection, the role of these drugs in the treatment of clinically stable HIV-infected children is not clear. OBJECTIVE: To evaluate the safety, tolerance, and virologic response produced by a change in antiretroviral therapy in HIV-infected children who were clinically and immunologically stable while receiving previous therapy. DESIGN: The Pediatric AIDS Clinical Trials Group 338, a multicenter, phase 2, randomized, open-label controlled trial conducted from February 6 to April 30, 1997 (patient entry period); patients were followed up for 48 weeks. SETTING: Pediatric HIV research clinics in the United States and Puerto Rico. PATIENTS: Two hundred ninety-seven antiretroviral-experienced, protease inhibitor-naive, clinically stable HIV-infected children aged 2 to 17 years. INTERVENTIONS: Children were randomized to receive zidovudine, 160 mg/m2 3 times per day, plus lamivudine, 4 mg/kg 2 times per day (n = 100); the same regimen plus ritonavir, 350 mg/m2 2 times per day (n = 100); or ritonavir, 350 mg/m2 2 times per day, and stavudine, 4 mg/kg 2 times per day (n = 97). MAIN OUTCOME MEASURE: Plasma HIV-1 RNA levels at study weeks 12 and 48, compared among the 3 treatment groups. RESULTS: At study week 12, 12% of patients in the zidovudine-lamivudine group had undetectable plasma HIV RNA levels (<400 copies/mL) compared with 52% and 54% of patients in the 2- and 3-drug ritonavir-containing groups, respectively (P<.001). Through study week 48, 70% of children continued receiving their ritonavir-containing regimen. At study week 48, 42% of children receiving ritonavir plus 2 nucleosides compared with 27% of those receiving ritonavir and a single nucleoside had undetectable HIV RNA levels (P = .04); however, similar proportions in each group continuing initial therapy had HIV RNA levels of less than 10000 copies/mL (58% vs 48%, respectively; P = .19). CONCLUSIONS: In our study, change in antiretroviral therapy to a ritonavir-containing regimen was associated with superior virologic response at study week 12 compared with change to a dual nucleoside analog regimen. More children receiving ritonavir in combination with 2 compared with 1 nucleoside analog had undetectable HIV RNA levels at study week 48.  相似文献   
6.
7.
BACKGROUND: In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF). METHODS: We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months. RESULTS: Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53). CONCLUSIONS: In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.  相似文献   
8.
BACKGROUND: We sought to evaluate the prognostic value of the 6-minute walk test in stable outpatients with heart failure. METHODS AND RESULTS: We examined the association of 6-minute walk test distance and outcomes among 541 patients enrolled in the Digitalis Investigation Group trial. Patients were grouped by total distance (< or =200 m, 201 m-300 m, 301 m-400 m, and >400 m) with median follow-up of 32 months. All-cause mortality for patients who walked < or =200 m was significantly higher than patients who walked >200 m (43.9% versus 23.3%, P<0.001), but mortality was comparable among patients who walked >200 m (201 m-300 m: 23.7%, 301 m-400 m: 25.2%, >400 m 19.8%, P for trend 0.45). Results were similar for death due to worsening heart failure (< or =200 m: 29.3%, 201 m-300 m: 7.6%, 301 m-400 m: 6.7%, >400 m: 6.1%, P for trend <0.001). In multivariable analysis, distance < or =200 m remained associated with increased mortality (< or =200 m: hazard ratio (HR) 1.47, 95% CI 0.96-2.27; >200 m: HR 1.00, Referent; P=0.07) and death due to worsening heart failure (< or =200 m: HR 2.89, 95% CI 1.54-5.41; >200 m: 1.00, Referent; P=0.001). CONCLUSIONS: The 6-minute walk test identifies patients who walk less than 200 m as being at markedly increased risk of death. Changing the 6-minute walk test to a time- and distance-based standard would improve the efficiency of the test while retaining the bulk of the prognostic information.  相似文献   
9.
Background Amiodarone has been shown to be safe in patients with acute myocardial infarction (AMI) who are at risk for sudden cardiac death. However, there is limited data concerning the safety of amiodarone in patients who experience AMI complicated by atrial fibrillation. Methods To determine the safety of amiodarone therapy, we conducted a retrospective analysis of elderly patients hospitalized with AMI who experienced atrial fibrillation and had survived to hospital discharge (n = 17,597). Amiodarone prescribed at discharge was evaluated for its association with short-term and long-term mortality in crude and adjusted analyses employing propensity score methods. Results Of the 17,597 patients, 550 patients (3.1%) were prescribed amiodarone, 2317 patients (13.2%) were prescribed other antiarrhythmic agents (excluded from analysis), and 14,730 (83.7%) were prescribed no antiarrhythmic medication at discharge. Thirty-day mortality rates were similar for patients prescribed amiodarone and those not prescribed amiodarone (6.8% amiodarone vs 5.4% no amiodarone, P = .21), but mortality at 1 year was higher among patients prescribed amiodarone (35.6% vs 31.6%, P = .001). However, amiodarone was not associated with mortality at 30 days (odds ratio 0.80, 95% CI 0.53-1.20) or at long-term follow-up (mean duration 612 days, hazard ratio 1.04, 95% CI 0.92-1.18) after multivariable modeling. Conclusions Amiodarone was not independently associated with short-term or long-term mortality in elderly patients discharged after a hospitalization for AMI complicated by atrial fibrillation. Although our data suggest that amiodarone may be safe to use in this population, randomized controlled trial data are needed to confirm this finding. (Am Heart J 2002;144:1095-101.)  相似文献   
10.

Background

Studies have suggested that cardiologists may provide higher quality heart failure care than generalists. However, national rates of specialty care during hospitalization for heart failure and factors associated with care by a cardiologist are unknown.

Methods

We assessed specialty care in a sample of Medicare patients hospitalized nationwide with heart failure between 1998 and 1999 (n = 25,869). Multivariable hierarchical logistic regression models were used to identify factors independently associated with treatment by a cardiologist.

Results

One-quarter (25.5%) of patients had a cardiologist as their attending physician, 31.3% of patients received a cardiology consult, and 43.2% of patients were not treated by a cardiologist during hospitalization. Older patients (age <75 years: referent; age 75-84 years: risk ratio [RR], 0.92; 95% CI, 0.86-0.98; age ≥85 years: RR, 0.81; 95% CI, 0.74-0.88) and women (RR, 0.87; 95% CI, 0.83-0.93) were less likely to have an attending cardiologist. Patients with a history of heart failure (RR, 1.13; 95% CI, 1.06-1.20), coronary disease (RR, 1.23; 95% CI, 1.14-1.32), coronary artery bypass grafting (RR, 1.42; 95% CI, 1.32-1.42), or percutaneous transluminal coronary angioplasty (RR, 1.30; 95% CI, 1.19-1.42) were more likely to be treated by a cardiologist, whereas patients with chronic obstructive pulmonary disease (RR, 0.74; 95% CI, 0.70-0.79) and dementia (RR, 0.61; 95% CI, 0.54-0.70) were less likely to be treated by a cardiologist. Patient race was not associated with treatment by a cardiologist. The strongest predictors of attending cardiology care were hospital factors, including large volume (>300 beds; RR, 1.45; 95% CI, 1.32-1.42) and geographic location (RR, 1.00 Northeast (referent) vs RR, 0.55; 95% CI 0.46-0.65 Midwest).

Conclusions

Slightly more than half of older patients with heart failure received care from a cardiologist. Several patient characteristics, including age and sex, were associated with the use of specialty care, suggesting that factors other than clinical presentation may independently influence the use of specialty care.  相似文献   
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