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91.
92.
AIMS: Although cardiac sympathetic activation is associated with adverse outcome in patients with chronic heart failure (CHF), the influence of renal sympathetic activity on outcome is unknown. We assessed the hypothesis that renal noradrenaline (NA) spillover is a predictor of the combined endpoint of all-cause mortality and heart transplantation in CHF. METHODS AND RESULTS: Sixty-one patients with CHF, New York Heart Association (NYHA) I-IV (66% NYHA III-IV), and left ventricular ejection fraction (LVEF) 26+/-9% (mean+/-SD) were studied with cardiac and renal catheterizations at baseline and followed for 5.5+/-3.7 years (median 5.5 years, range 12 days to 11.6 years). Nineteen deaths and 13 cases of heart transplantation were registered. Only renal NA spillover above median, 1.19 (interquartile range 0.77-1.43) nmol/min, was independently associated with an increased relative risk (RR) of the combined endpoint (RR 3.1, 95% CI 1.2-7.6, P=0.01) in a model also including total body NA spillover, LVEF, glomerular filtration rate (GFR), renal blood flow, cardiac index, aetiology, and age. CONCLUSION: Renal noradrenergic activation has a strong negative predictive value on outcome independent of overall sympathetic activity, GFR, and LVEF. These findings suggest that treatment regimens that further reduce renal noradrenergic stimulation could be advantageous by improving survival in patients with CHF.  相似文献   
93.
The relative contribution of transcytosis vs. large pore transport to the passage of macromolecules across microvascular endothelia has been a controversial issue for nearly half a century. To separate transcytosis from 'porous' transport, the transcytosis inhibitors N-ethylmaleimide (NEM) and filipin have been tested in in situ or ex vivo perfused organs with highly conflicting results. In continually weighed isolated perfused organs, where measurements of pre- and post-capillary resistances, capillary pressure and capillary filtration coefficients can be repeatedly performed, high doses of NEM and filipin increased the bulk transport of macromolecules from blood to tissue, despite producing vasoconstriction. By contrast, in in situ perfused organs, marked reductions in the tissue uptake of albumin tracer have been observed after NEM and filipin. When tissue cooling has been employed as a means of inhibiting (active) transcytosis, results have invariably shown a low cooling sensitivity of albumin transport, compatible with passive transendothelial passage of albumin. This observation is further strengthened by the commonly observed dependence of albumin transport upon the capillary pressure and the rate of transcapillary convection. For low-density lipoprotein (LDL), a cooling-sensitive, non-selective transport component has been discovered, which may be represented by filtration through paracellular gaps, lateral diffusion through transendothelial channels formed by fused vesicles, or by transcytosis. From a physiological standpoint there is little evidence supporting active transendothelial transport of most plasma macromolecules. This seems to be supported by studies on caveolin-1-deficient mice lacking plasmalemmal vesicles (caveolae), in which there are no obvious abnormalities in the transendothelial transport of albumin, immunoglobulins or lipoproteins. Nevertheless, specific transport in peripheral capillaries of several hormones and other specific substances, similar to that existing across the blood-brain barrier, still remains as a possibility.  相似文献   
94.
OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis.  相似文献   
95.
96.
Abstract

Background and aims

Accurate biomarkers for quantifying liver fibrosis are important for clinical practice and trial end-points. We compared the diagnostic performance of magnetic resonance imaging (MRI), including gadoxetate-enhanced MRI and 31P-MR spectroscopy, with fibrosis stage and serum fibrosis algorithms in a clinical setting. Also, in a subset of patients, MR- and transient elastography (MRE and TE) was evaluated when available.  相似文献   
97.
A thorough assessment of the extent and severity of spasticity, and its effect on functioning, is central to the effective management of spasticity in persons with spinal cord damage (SCD). These individuals however do not always receive adequate assessment of their spasticity. Inadequate assessment compromises management when the effect of spasticity and/or need for intervention are not fully recognized. Assessment is also central to determining treatment efficacy. A barrier to spasticity assessment has been the lack of consensus on clinical and functional measures suitable for routine clinical practice. To extend on existing work, a working group of the Ability Network identified and consolidated information on possible measures, and then synthesized and formulated findings into practical recommendations for assessing spasticity and its effect on function in persons with SCD. Sixteen clinical and functional measures that have been used for this purpose were identified using a targeted literature review. These were mapped to the relevant domains of the International Classification of Functioning, Disability and Health to assess the breadth of their coverage; coverage of many domains was found to be lacking, suggesting a focus for future work. The advantages, disadvantages, and usefulness of the measures were assessed using a range of criteria, with a focus on usefulness and feasibility in routine clinical practice. Based on this evaluation, a selection of measures suitable for initial and follow-up assessments are recommended. The recommendations are intended to have broad applicability to a variety of health care settings where people with SCD are managed.  相似文献   
98.
AimsAZD0837 is a novel oral anticoagulant investigated in clinical studies for stroke prevention in patients with atrial fibrillation (AF). It is bioconverted to its active form, AR‐H067637, a potent, specific and reversible thrombin inhibitor. The effects on coagulation biomarkers were correlated with the pharmacokinetic (PK) exposure of AR‐H067637 to guide selection of the effective dose regimen for a confirmatory efficacy study in AF patients.MethodsBlood samples were obtained from 601 AF patients randomized to one of four doses of AZD0837 (blinded treatment) or dose‐adjusted vitamin K antagonists (VKA, open treatment) for 3–9 months. A pharmacodynamic model was developed to describe the time course of the AR‐H067637 exposure dependent effects and the effect of VKA on fibrin D‐dimer. The thrombin generation measured ex vivo in venous plasma was also investigated.ResultsThe PK exposure of AR‐H067637 was stable with an interindividual variability of 33% and no or minor influence of patient demographics or comedications. For AZD0837, D‐dimer levels decreased with more rapid onset than for VKA. The decrease in D‐dimer levels correlated with steady‐state plasma concentrations (C ss) of AR‐H067637, with a maximum decrease of baseline D‐dimer levels estimated to approximately 60% for both AZD0837 and VKA therapy. The effect on thrombin generation correlated closely with the plasma concentration of AR‐H067637.ConclusionsThe effects on thrombin generation and fibrin D‐dimer levels correlated with the plasma concentration of its active form and provided comparable effects to well‐controlled VKA therapy at an exposure at least corresponding to the 300 mg once daily dose of AZD0837.  相似文献   
99.
BackgroundWe compared physical functioning, mental health, and quality of life (QoL) of patients with different subtypes of congenital heart disease (CHD) in a large international sample and investigated the role of functional class in explaining the variance in outcomes across heart defects.MethodsIn the cross-sectional Assessment of Patterns of Patient-Reported Outcome in Adults with Congenital Heart Disease-International Study (APPROACH-IS), we enrolled 4028 adult patients with CHD from 15 countries. Diagnostic groups with at least 50 patients were included in these analyses, yielding a sample of 3538 patients (median age: 32 years; 52% women). Physical functioning, mental health, and QoL were measured with the SF-12 health status survey, Hospital Anxiety and Depression Scale (HADS), linear analog scale (LAS) and Satisfaction with Life Scale, respectively. Functional class was assessed using the patient-reported New York Heart Association (NYHA) class. Multivariable general linear mixed models were applied to assess the relationship between the type of CHD and patient-reported outcomes, adjusted for patient characteristics, and with country as random effect.ResultsPatients with coarctation of the aorta and those with isolated aortic valve disease reported the best physical functioning, mental health, and QoL. Patients with cyanotic heart disease or Eisenmenger syndrome had worst outcomes. The differences were statistically significant, above and beyond other patient characteristics. However, the explained variances were small (0.6% to 4.1%) and decreased further when functional status was added to the models (0.4% to 0.9%).ConclusionsSome types of CHD predict worse patient-reported outcomes. However, it appears that it is the functional status associated with the heart defect rather than the heart defect itself that shapes the outcomes.  相似文献   
100.
On the organization of an early arthritis clinic   总被引:2,自引:0,他引:2  
Early active treatment with disease-modifying anti-rheumatic drugs has become standard management for patients with recent-onset rheumatoid arthritis. A number of questions, however, remain unresolved for practising clinicians, for example how early and how actively to treat and what the treatment goals should be. This chapter summarizes some recent data that have added important empirical evidence on these issues. It has thus been demonstrated that the formal organization of an early arthritis clinic shortens the referral time from primary care, that a delay in the institution of disease-modifying drug treatment leads to decreased long-term function and that early active treatment with pharmacotherapy as well as team-based care may increase occupational capacity. It is argued that adopting a day care approach in the initial encounter with specialist care may increase the possibility for patients actively to understand the disease and their own potentials to diminish and cope with its effects. The further development of care for early arthritis patients with new, potentially efficient but also expensive drugs will increase the requirement for a structured documentation of outcomes, systems for such documentation being discussed in the chapter.  相似文献   
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