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41.
A 75‐year‐old male patient was referred for longstanding atrial fibrillation ablation. We performed this procedure combining an epicardial and endocardial approach. Under general anesthesia and via a left‐sided thoracoscopic approach, we isolated the pulmonary veins (PVs) and the roofline and inferior line were created using a radiofrequency tool. To isolate the endocardial PVs, a transseptal puncture was performed via the groin, and a cryoablation CoolLoop catheter (AFreeze GmbH, Innsbruck, Austria) was advanced into the left atrium. Ice crystals started to appear on the epicardial surface of the left inferior PV antrum after 121 seconds later, those crystals had formed an ice plaque. For the first time in humans, we were able to visualize the transmural effects of cryothermal energy ablation via a CoolLoop catheter on the epicardial surface of the ostium of the PV.  相似文献   
42.
Background: Leber congenital amaurosis (LCA) is most often an autosomal recessive disorder. We report a father and son with autosomal dominant LCA due to a mutation in the CRX gene.

Materials and Methods: DNA screening using an allele specific assay of 90 of the most common LCA-causing variations in the coding sequences of AIPL1, CEP290, CRB1, CRX, GUCY2D, RDH12 and RPE65 was performed on the father. Automated DNA sequencing of his son examining exon 3 of the CRX gene was subsequently performed.

Results: Both father and son have a heterozygous single base pair deletion of an adenine at codon 153 in the coding sequence of the CRX gene resulting in a frameshift mutation.

Conclusion: Mutations involving the CRX gene may demonstrate an autosomal dominant inheritance pattern for LCA.  相似文献   

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This study shows clinical efficacy and safety profile of an off-label use of caplacizumab for the treatment of immune-mediated thrombotic thrombocytopenic purpura in a middle-aged obese male patient manifesting aphasia, weakness and unconsciousness. Routine blood tests revealed haemolytic anaemia, severe thrombocytopenia (platelet count = 20 × 109/L) and moderate creatinine increase. Diagnosis was based on the clinical judgement and laboratory determinations (undetectable ADAMTS13 activity and presence of anti-ADAMTS13 antibodies). The patient underwent plasma-exchange and an adjunctive treatment with prednisone (1 mg/Kg/day), but the occurrence of a refractory and exacerbated form of disease suggested also using rituximab (375 mg/m2 weekly for 4 weeks) and caplacizumab as salvage treatments. The caplacizumab was given at 10 mg/day subcutaneously without the first intravenous bolus. Because von Willebrand factor inhibition, platelet count recovery and remission of symptoms were achieved, use of caplacizumab with this scheme appeared to be as effective as the approved one. Although this is an off-label use, this case highlights the potential of this new treatment, in terms of drug's efficacy and safety.  相似文献   
47.

Objectives:

To determine the effective dose and CT dose index (CTDI) for a range of imaging protocols using the Sirona GALILEOS® Comfort CBCT scanner (Sirona Dental Systems GmbH, Bensheim, Germany).

Methods:

Calibrated optically stimulated luminescence dosemeters were placed at 26 sites in the head and neck of a modified RANDO® phantom (The Phantom Laboratory, Greenwich, NY). Effective dose was calculated for 12 different scanning protocols. CTDI measurements were also performed to determine the dose–length product (DLP) and the ratio of effective dose to DLP for each scanning protocol.

Results:

The effective dose for a full maxillomandibular scan at 42 mAs was 102 ± 1 μSv and remained unchanged with varying contrast and resolution settings. This compares with 71 μSv for a maxillary scan and 76 μSv for a mandibular scan with identical milliampere-seconds (mAs) at high contrast and resolution settings.

Conclusions:

Changes to mAs and beam collimation have a significant influence on effective dose. Effective dose and DLP vary linearly with mAs. A collimated maxillary or mandibular scan decreases effective dose by approximately 29% and 24%, respectively, as compared with a full maxillomandibular scan. Changes to contrast and resolution settings have little influence on effective dose. This study provides data for setting individualized patient exposure protocols to minimize patient dose from ionizing radiation used for diagnostic or treatment planning tasks in dentistry.  相似文献   
48.

Purpose

To highlight a new imaging acquisition protocol during 18F-fluorocholine PET/CT in patients with biochemical recurrence after RP.

Methods

A total of 146 patients with PSA levels between 0.2 and 1 ng/ml with negative conventional imaging who did not receive salvage treatment were prospectively enrolled. Imaging acquisition protocol included an early dynamic phase (1–8 min), a conventional whole body (10–20 min), and a late phase (30–40 min). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were measured. Univariable and multivariable analyses were performed to identify independent predictors of positive PET/CT.

Results

The median trigger PSA was 0.6 ng/ml (IQR 0.43–0.76). Median PSA doubling time (PSA DT) was 7.91 months (IQR 4.42–11.3); median PSA velocity (PSAV) was 0.02 ng/ml per month (IQR 0.02–0.04). Overall, 18F-fluorocholine PET/CT was positive in 111 of 146 patients (76 %). Out of 111 positive examinations, 80 (72.1 %) were positive only in the early dynamic phase. Sensitivity, specificity, PPV, NPV, and accuracy were 78.9, 76.9, 97.2, 26.3, and 78.7 %, respectively. At multivariable logistic regression, trigger PSA ≥ 0.6 ng/ml [odds ratio (OR) 3.13; p = 0.001] and PSAV ≥ 0.04 ng/ml per month (OR 4.95; p = 0.004) were independent predictors of positive PET/CT. The low NPV remains the main limitation of PET/CT in this setting of patients.

Conclusions

The increased sensitivity, thanks to the early imaging acquisition protocol, makes 18F-fluorocholine PET/CT an attractive tool to detect prostate cancer recurrences in patients with a PSA level <1 ng/ml.
  相似文献   
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Background

Young patients presenting with symptomatic Brugada syndrome have very high risks for ventricular arrhythmias and should be carefully considered for implantable cardioverter-defibrillator (ICD) placement. However, this therapy is associated with high rates of inappropriate shocks and device-related complications.

Objectives

This study investigated clinical features, management, and long-term follow-up of young patients with Brugada syndrome and ICD.

Methods

Patients diagnosed with Brugada syndrome, who underwent implantation of an ICD at an age of ≤20 years, were studied.

Results

The study included 35 consecutive patients. The mean age at ICD placement was 13.9 ± 6.2 years. Ninety-two percent were symptomatic; 29% presented with aborted sudden cardiac death and 63% with syncope. During a mean follow-up period of 88 months, sustained ventricular arrhythmias were treated by the ICD in 9 patients (26%), including shocks in 8 patients (23%) and antitachycardia pacing in 1 patient (3%). Three patients (9%) died in an electrical storm. Seven patients (20%) experienced inappropriate shocks, and 5 patients (14%) had device-related complications. Aborted sudden cardiac death and spontaneous type I electrocardiogram were identified as independent predictors of appropriate shock occurrence.

Conclusions

ICD therapy is an effective strategy in young patients with symptomatic Brugada syndrome, treating potentially lethal arrhythmias in >25% of patients during follow-up. Appropriate shocks were significantly associated with previously aborted sudden cardiac death and spontaneous type I electrocardiograms. However, ICDs are frequently associated with complications and inappropriate shocks, both of which remain high regardless of careful device implantation and programming.  相似文献   
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