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71.
Aldosterone antagonists (or mineralocorticoid receptor antagonists [MRAs]) are guideline-recommended therapy for patients with moderate to severe heart failure (HF) symptoms and reduced left ventricular ejection fraction (LVEF), and in postmyocardial infarction patients with HF. The Eplerenone in Mild Patients Hospitalization and Survival Study in Heart Failure (EMPHASIS-HF) trial evaluated the MRA eplerenone in patients with mild HF symptoms. Eplerenone reduced the risk of the primary endpoint of cardiovascular death or HF hospitalization (hazard ratio [HR] 0.63, 95% confidence interval [CI] 0.54-0.74, P < .001) and all-cause mortality (adjusted HR 0.76, 95% CI 0.62-0.93, P < .008) after a median of 21 months. Based on EMPHASIS-HF, an MRA is recommended for patients with New York Heart Association (NYHA) Class II-IV symptoms and reduced LVEF (<35%) on standard therapy (Strength of Evidence A). Patients with NYHA Class II symptoms should have another high-risk feature to be consistent with the EMPHASIS-HF population (age >55 years, QRS duration >130 msec [if LVEF between 31% and 35%], HF hospitalization within 6 months or elevated B-type natriuretic peptide level). Renal function and serum potassium should be closely monitored. Dose selection should consider renal function, baseline potassium, and concomitant drug interactions. The efficacy of eplerenone in patients with mild HF symptoms translates into a unique opportunity to reduce morbidity and mortality earlier in the course of the disease.  相似文献   
72.
Cardiac resynchronization therapy (CRT) improves survival, symptoms, quality of life, exercise capacity, and cardiac structure and function in patients with New York Heart Association (NYHA) functional class II or ambulatory class IV heart failure (HF) with wide QRS complex. The totality of evidence supports the use of CRT in patients with less severe HF symptoms. CRT is recommended for patients in sinus rhythm with a widened QRS interval (≥150 ms) not due to right bundle branch block (RBBB) who have severe left ventricular (LV) systolic dysfunction and persistent NYHA functional class II-III symptoms despite optimal medical therapy (strength of evidence A). CRT may be considered for several other patient groups for whom evidence of benefit is clinically significant but less substantial, including patients with a QRS interval of ≥120 to <150 ms and severe LV systolic dysfunction who have persistent mild to severe HF despite optimal medical therapy (strength of evidence B), some patients with atrial fibrillation, and some with ambulatory class IV HF. Several evidence gaps remain that need to be addressed, including the ideal threshold for QRS duration, QRS morphology, lead placement, degree of myocardial scarring, and the modality for evaluating dyssynchrony. Recommendations will evolve over time as additional data emerge from completed and ongoing clinical trials.  相似文献   
73.
Authorship is the currency of an academic career. Scientific publications have significant academic and financial implications. Several standard authorship guidelines exist, and the International Committee of Medical Journal Editors (ICMJE) is the most popular amongst them. There are increasing concerns about the ethics of publications with the rise of inappropriate authorship. The most important reason appears to be a lack of knowledge and awareness of the authorship guidelines and what actions constitute unethical behaviors. There is a need to incorporate standard guidelines in medical curricula and conduct structured training and education programs for researchers across the board. The current perspective describes the significant concepts of appropriate and inappropriate authorship, and the possible measures being formulated to shape the future of authorship.  相似文献   
74.
Diuretics and vasodilators have been the cornerstone of heart failure (HF) therapy for decades. Although not shown to reduce mortality, diuretic and vasodilator therapy remain commonplace for treating acute decompensated HF, with diuretics being the mainstay of therapy for the removal of excess fluid in all patients with HF. This article discusses results of recent trials concerning diuretic or vasodilator therapy and HF, including the Diuretic Optimization Strategies Evaluation (DOSE) trial, the Placebo-Controlled Randomized Study of the Selective A1 Adenosine Receptor Antagonist Rolofylline for Patients Hospitalized With Acute Decompensated Heart Failure and Volume Overload to Assess Treatment Effect on Congestion and Renal Function (PROTECT), and the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST), as well as results from the Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure (ASCEND-HF) trial and the Preliminary Study of Relaxin in Acute Heart Failure (Pre-RELAX-AHF).  相似文献   
75.
Elevated levels of circulating proinflammatory cytokines and adipokines have been repeatedly associated with increased risk for clinically manifest (Stage C) heart failure in large cohort studies. However, the role of low-grade, subclinical inflammatory activity in the transition from risk factors (Stage A heart failure) to structural heart disease (Stage B heart failure) is less well understood. Recent evidence suggests that chronic low-grade inflammatory activity is involved in most mechanisms underlying progression of structural heart disease, including ventricular remodeling after ischemic injury, response to pressure and volume overload, and myocardial fibrosis. Inflammation also contributes to progression of peripheral vascular changes.  相似文献   
76.
Recently, carbon nanostructures have attracted interest because of their unique properties and interesting applications. Here, CoC@SiO2-850 (3) and CoC@SiO2-600 (4) cobalt–carbon/silica nanocomposites were prepared by solid-state pyrolysis of anthracene with Co(tph)(2,2′-bipy)·4H2O (1) complex in the presence of silica at 850 and 600 °C, respectively, where 2,2′-bipy is 2,2′-bipyridine and tph is the terephthalate dianion. Moreover, Co(μ-tph)(2,2′-bipy) (2) was isolated and its X-ray structure indicated that cobalt(ii) has a distorted trigonal prismatic coordination geometry. 2 is a metal–organic framework consisting of one-dimensional zigzag chains within a porous grid network. 3 and 4 consist of cobalt(0)/cobalt oxide nanoparticles with a graphitic shell and carbon nanotubes embedded in the silica matrix. They were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). XPS revealed that the nanocomposites are functionalized with oxygen-containing groups, such as carboxylic acid groups. In addition, the presence of metallic cobalt nanoparticles embedded in graphitized carbon was verified by XRD and TEM. The efficiency of 3 for adsorption of crystal violet (CV) dye was investigated by batch and column experiments. At 25 °C, the Langmuir adsorption capacity of 3 for CV was 214.2 mg g−1 and the fixed-bed column capacity was 36.3 mg g−1. The adsorption data were well fitted by the Freundlich isotherm and pseudo-second-order kinetic model. The adsorption process was spontaneous and endothermic.

A cobalt–carbon@silica nanocomposite was synthesized from a cobalt 2,2′-bipyridine terephthalate complex and its adsorption behavior towards crystal violet dye was tested using batch and column techniques.  相似文献   
77.

Background

Nighttime blood pressure (BP) and systolic BP variability on ambulatory blood pressure monitoring (ABPM) have been strongly associated with target-organ damage in hypertensive adults. The clinical relevance of these variables in children with hypertension remains under-studied.

Methods

The study group included children aged 5–18 years old referred to the outpatient nephrology clinic for an elevated casual BP who underwent an ABPM and echocardiography (ECHO) study and did not have secondary hypertension. The interpretation of ABPM parameters and left ventricular mass index (LVMI) was based on normative references.

Results

Seventy-two children fulfilled the inclusion criteria. The association of various potential predictors including age, BMI z-score, casual BP z-score and ABPM parameters (BP z-score, BP load, nocturnal dipping and BP variability- within-subject standard deviation (SD) of BP) with LVMI was analyzed. On adjusted regression analysis, nighttime systolic BP load [standardized regression coefficient (β) 0.23; p?<?0.05] and daytime systolic BP variability (β 0.37; p?<?0.05) had significant association with LVMI.

Conclusions

In children with primary hypertension, nighttime systolic BP load and daytime systolic BP variability had a stronger association with LVMI than casual BP and other ABPM parameters. Future longitudinal studies are needed to establish the causality among these variables.  相似文献   
78.
Background: Periodontitis may occur in patients with and without type 2 diabetes (T2D). It may be hypothesized that the gingival crevicular fluid (GCF) cytokine profile in patients with periodontitis with poorly controlled T2D may differ from the GCF cytokine profile in medically healthy individuals with periodontitis. The aim was to review the cytokine profiles in the GCF of patients with periodontitis with and without T2D. Methods: Databases were searched from 1988 to August 2011 using different combinations of various keywords. Titles and abstracts of articles that satisfied the eligibility criteria were screened by the authors and checked for agreement. Only articles published in English were included. Results: Ten studies were included. Two studies reported GCF concentrations of interleukin (IL)‐6 to be higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. Two studies showed GCF IL‐6 levels to be higher in periodontitis with T2D compared to medically healthy subjects without periodontitis. In one study GCF levels of IL‐17, IL‐23, and interferon‐γ were higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. In one study, GCF concentrations of IL‐8 were significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Three studies reported GCF levels of IL‐1α to be significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Conclusion: The GCF cytokine profile in patients with and without T2D seems to be governed by the intensity of periodontal inflammation and the role of T2D in this regard is rather secondary.  相似文献   
79.

Background

Laparoscopic Roux en-Y gastric bypass (LRYGB) achieves sustained long-term weight loss and reduced mortality in morbidly obese patients. It is routinely performed using an ante- or retrocolic approach with the jejuno-jejunostomy constructed in the infracolic compartment. We have modified the standard technique of performing LRYGB by constructing both anastomoses in the supracolic compartment. This study describes the outcomes of consecutive primary LRYGB performed using this novel retrocolic–supracolic approach.

Methods

Data were prospectively collected on consecutive primary LRYGB performed in a tertiary-referral Bariatric Centre in the United Kingdom from September 2009 to March 2013. Data included demographics, operative outcomes (duration of surgery, postoperative anastomotic leak/bleeding/reoperations), development of strictures, length of stay, excess weight loss (EWL) and resolution of diabetes mellitus.

Results

Hand-sewn LRYGB was successfully performed using the retrocolic–supracolic approach in 300 of 307 (98 %) consecutive patients (72 % female). Median (IQR) age, weight and baseline body mass index were 49 (41–56) years, 146 (134–163) kg and 52.9 (48.8–57.2) kg/m2, respectively. There were 4 (1.3 %) anastomotic leaks and 8 (2.6 %) postoperative bleeds. The 30-day reoperation rate was 1.6 %. Median (IQR) hospital stay was 2 (2–2) days. Postoperative dysphagia requiring endoscopic balloon dilatation occurred in 19 (6.3 %) patients. Mean ± SD 12-month EWL was 69.9 ± 19.0 %. Within the follow-up period, 81 % of patients with type II diabetes mellitus achieved remission and 19 % reduced dosage of diabetes medication.

Conclusions

LRYGB performed using the retrocolic–supracolic approach was safe, feasible, technically advantageous and resulted in clinical outcomes akin to the standard infracolic approach.
  相似文献   
80.
Cardiovascular disease (CVD) is the leading cause of death worldwide, and due to the lack of early detection techniques, the incidence of CVD is increasing day by day. In order to address this limitation, a knowledge based system with embedded intelligent heart sound analyser (KBHSA) has been developed to diagnose cardiovascular disorders at early stages. The system analyses digitized heart sounds that are recorded from an electronic stethoscope using advanced digital signal processing and artificial intelligence techniques. KBHSA takes into account data including the patient's personal and past medical history, clinical examination, auscultation findings, chest x-ray and echocardiogram, and provides a list of diseases that it has diagnosed. The system can assist the general physician in making more accurate and reliable diagnosis under emergency conditions where expert cardiologists and advanced equipment are not readily available. To test the validity of the system, abnormal heart sound samples and medical data from 40 patients were recorded and analysed. The diagnoses made by the system were counter checked by four senior cardiologists in Malaysia. The results show that the findings of KBHSA coincide with those of cardiologists.  相似文献   
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