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Introduction

Optimal opacification of the pulmonary vasculature is a fundamental factor of a diagnostic quality computed tomography pulmonary angiogram (CTPA). This retrospective study examined the feasibility of utilising a noise-optimised monoenergetic reconstruction of the dual-energy computed tomography pulmonary angiogram (DE-CTPA) as an additional protocol to increase vessel opacification.

Method

The study involved a retrospective analysis of 129 patients, 69 males (average age 58 years), 60 females (average age 56 years) who underwent a DE-CTPA at a tertiary referral hospital. Linear blended 120 kilovoltage (kV) images (LB120) dual-energy (DE) data sets (50% 100 kV and 50% 140 kV) were compared to noise-optimised virtual monoenergetic image reconstruction (VMI+) at 40 kiloelectron volts (VMI+40). The attenuation of the pulmonary trunk measured in Hounsfield units (HU) between the equivalent axial slices of the LB120 data set and the VMI+40 data set underwent statistical analysis via a Wilcoxon paired-sample test.

Results

VMI+40 (1161.500 HU) yielded a statistically significant increase in median attenuation within the pulmonary trunk compared to the LB120 (304.400 HU), with a median difference between monoenergetic reconstruction and standard dual energy of data sets of 827.5 HU (P < .001).

Conclusions

VMI+40 of the DE-CTPA scan demonstrates a statistically significant increase in vessel attenuation in all cases and may have utility in reducing the rates of indeterminate or repeated studies.  相似文献   
3.
Lifestyle is fundamental in chronic disease prevention and management, and it has been recommended as a first‐line treatment in the Australian polycystic ovary syndrome (PCOS) guideline 2011. The first international evidence‐based guideline on PCOS was developed in 2018, which expanded the scope and evidence in the Australian guideline. This paper summarizes the lifestyle recommendations and evidence summaries from the guideline. International multidisciplinary guideline development groups delivered the International Evidence‐based Guideline for the Assessment and Management of Polycystic Ovary Syndrome 2018. The process followed the Appraisal of Guidelines for Research and Evaluation II and The Grading of Recommendations, Assessment, Development and Evaluation framework. Extensive communication and meetings addressed six prioritized clinical questions through five reviews. Evidence‐based recommendations were formulated before consensus voting within the panel. Evidence shows the benefits of multicomponent lifestyle intervention, efficacy of exercise and weight gain prevention with no specific diet recommended. Lifestyle management is the first‐line management in the intervention hierarchy in PCOS. Multicomponent lifestyle intervention including diet, exercise and behavioural strategies is central to PCOS management with a focus on weight and healthy lifestyle behaviours. The translation programme optimizes reach and dissemination for health professionals and consumers.  相似文献   
4.
IntroductionLung-MAP S1400K was designed to evaluate the response to telisotuzumab vedotin, an antibody-drug conjugate targeting c-MET, in patients with c-MET–positive squamous cell carcinoma (SCC).Patients and MethodsPatients with previously treated SCC with c-MET–positive tumors (H score ≥ 150, Ventana SP44 assay) were enrolled into 2 cohorts: Cohort 1 (immune checkpoint inhibitor-naive) and Cohort 2 (immune checkpoint inhibitor refractory). Telisotuzumab vedotin 2.7 mg/kg was administered intravenously every 3 weeks until disease progression or unacceptable toxicity. Response assessments were performed every 6 weeks. The primary endpoint was response by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Secondary endpoints included progression-free survival, overall survival, response within cohort, duration of response, and toxicities. Interim analysis was planned after 20 evaluable patients, with ≥ 3 responses needed to continue enrollment.ResultsForty-nine patients (14% of screened patients) were assigned to S1400K, 28 patients enrolled (15 in Cohort 1 and 13 in Cohort 2), and 23 were eligible. S1400K closed on December 21, 2018 owing to lack of efficacy. Two responses (response rate of 9%; 95% confidence interval, 0%-20%) were reported in cohort 1 (1 complete and 1 unconfirmed partial response), whereas 10 patients had stable disease, with a disease control rate of 52%. The median overall and progression-free survival was 5.6 and 2.4 months, respectively. There were 3 grade 5 events (2 pneumonitis, in Cohort 2, and 1 bronchopulmonary hemorrhage, in Cohort 1).ConclusionTelisotuzumab vedotin failed to meet the pre-specified response needed to justify continuing enrollment to S1400K. Pneumonitis was an unanticipated toxicity observed in patients with SCC.  相似文献   
5.

Background

Before mutation testing of the epidermal growth factor receptor (EGFR) gene was recognized as highly associated with the activity of EGFR tyrosine kinase inhibitors (TKIs), clinically defined patient populations with bronchioloalveolar carcinoma (BAC) and never smokers were identified as likely to benefit from EGFR TKIs. From preclinical and clinical data suggesting potentially improved efficacy with a combination of an EGFR TKI and the antiangiogenic agent bevacizumab, the Southwestern Oncology Group (SWOG) initiated paired phase II trials to evaluate the combination of erlotinib/bevacizumab in patients with advanced BAC (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636).

Materials and Methods

Eligible patients with BAC or adenocarcinoma with BAC features (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636) received erlotinib 150 mg/day with bevacizumab 15 mg/kg until progression or prohibitive toxicity. Never smokers with BAC were preferentially enrolled to SWOG S0636. The primary endpoint for both trials was overall survival.

Results

A total of 84 patients were enrolled in the SWOG S0635 trial and 85 in the SWOG S0636 trial. The objective response rate was 22% (3% complete response) in the SWOG S0635 trial and 50% (38% confirmed; 3% complete response) in the SWOG S0636 trial. The median progression-free survival was 5 and 7.4 months in the S0635 and S0636 trials, respectively. The median overall survival was 21 and 29.8 months, respectively. Toxicity consisted mainly of rash and diarrhea in both trials.

Conclusion

Although the field has moved toward molecular, rather than clinical, selection of patients as optimal candidates for EGFR TKI therapy, these results support the hypothesis that a subset of patients in whom erlotinib is particularly active could receive an incremental benefit from the addition of bevacizumab.  相似文献   
6.
Benzodiazepines (BZs) were introduced into clinical practice in the 1960's. The major indications for their use are to treat anxiety, as sedative‐hypnotics, anti‐convulsants, muscle relaxants and pre‐anaesthetics. They replaced barbiturate tranquillisers and hypnotics which have significant and well‐documented dependence and overdose risks (Dupont & Saylor, 1991). Initially the BZs were thought not to induce dependence, to be of low overdose risk and to be relatively free of adverse side‐effects. However, during the 1970's it became apparent that these drugs do have quite serious adverse effects, especially in the elderly fluergens, 1993), and that dependence and withdrawal symptoms are not uncommon. Regular use of BZs, at normally prescribed doses, can lead to dependence in patients who do not abuse either BZs or other drugs (Owen & Tyrer, 1983). Dependence can develop in as little as 6–8 weeks' continuous administration (Lader & Petursson, 1983), and may persist for many months (Ashton, 1984). Symptoms include anxiety, insomnia, depression, aches and pains, muscle spasm, gastrointestinal disorders, and increased sensitivity to light sound & touch (Petursson & Lader, 1981; Ashton, 1984). At the same time the problems of drug interactions, whereby polydrug users add BZs to their drug cocktails, have brought them to the attention of the criminal justice system. This paper will review the mechanisms of action and patterns of use of BZs in Australia. The major adverse effects of BZs, on psychomotor skills and memory, in addition to the less common paradoxical effects on aggressive behaviour, will be discussed. The wide‐spread, long‐term use of these drugs, at least by certain groups, has consequences for the criminal justice system.  相似文献   
7.
8.

BACKGROUND:

In patients with advanced lung cancer, overall survival is largely influenced by progression status. Because progression‐free survival (PFS)‐based endpoints are controversial, the authors evaluated the impact of the progression date (PD) determination approach on PFS estimates.

METHODS:

Individual patient data from 21 trials (14 North Central Cancer Treatment Group trials and 7 Southwest Oncology Group trials) were used. The reported PD (RPD) was defined as either the radiographic scan date or the clinical deterioration date. PD was determined using Method 1 (M1), the RPD; M2, 1 day after the last progression‐free scan; M3, midpoint between the last progression‐free scan and the RPD; and M4, an interval‐censoring approach. PFS was estimated using Kaplan‐Meier (M1‐M3), and maximum‐likelihood (M4) methods. Simulation studies were performed to understand the impact of the length of time elapsed between the last progression‐free scan and the PD on time‐to‐progression estimates.

RESULTS:

PFS estimates using the RPD were the highest, and M2 was the most conservative. M3 and M4 were similar because the majority of progressions occurred during treatment (ie, frequent disease assessments). M3 was influenced less by the length of the assessment schedules (percentage difference from the true time‐to‐progression, <1.5%) compared with M1 (11% to 30%) and M2 (?8% to ?29%). The overall study conclusion was unaffected by the method used for randomized trials.

CONCLUSIONS:

The magnitude of difference in the PFS estimates was large enough to alter trial conclusions in patients with advanced lung cancer. The results indicate that standards for PD determination, the use of sensitivity analyses, and randomized trials are critical when designing trials and reporting efficacy using PFS‐based endpoints. Cancer 2012. © 2012 American Cancer Society.  相似文献   
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