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1.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
2.
ObjectiveTo determine if individuals with chronic ankle instability (CAI) demonstrate altered landing kinematics, muscle activity, and impaired dynamic postural stability during a unilateral jump-landing task.Methods21 studies were included from PubMed, MEDLINE, Embase and CINAHL searched on September 26, 2021. Mean differences in joint angles and muscle activity between CAI and controls were analysed as continuous variables and pooled using a random-effects model to obtain standardised mean differences and 95% confidence intervals. Dynamic postural stability measured using time to stabilisation (TTS) was assessed qualitatively.ResultsWe found greater plantarflexion (pooled SMD = 0.33, 95%CI [0.02,0.65]), reduced knee flexion (pooled SMD = −0.67, 95%CI [−0.97, −0.37]), and reduced hip flexion (pooled SMD = −0.52, 95%CI [−0.96, −0.07]) in CAI after landing. Regarding muscle activity, we observed reduced peroneus longus muscle activation (pooled SMD = −0.77, 95% CI [−1.17, −0.36]) in CAI prior to landing.ConclusionOur study provides preliminary evidence of altered landing kinematics in the sagittal plane and reduced peroneus muscle activity in CAI during a dynamic jump-landing task. These results may have clinical implications in the development of more effective and targeted rehabilitation programmes for patients with CAI. 相似文献
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4.
Over the past 20 years there has been a growing interest in the neural underpinnings of cost/benefit decision-making. Recent studies with animal models have made considerable advances in our understanding of how different prefrontal, striatal, limbic and monoaminergic circuits interact to promote efficient risk/reward decision-making, and how dysfunction in these circuits underlies aberrant decision-making observed in numerous psychiatric disorders. This review will highlight recent findings from studies exploring these questions using a variety of behavioral assays, as well as molecular, pharmacological, neurophysiological, and translational approaches. We begin with a discussion of how neural systems related to decision subcomponents may interact to generate more complex decisions involving risk and uncertainty. This is followed by an overview of interactions between prefrontal-amygdala-dopamine and habenular circuits in regulating choice between certain and uncertain rewards and how different modes of dopamine transmission may contribute to these processes. These data will be compared with results from other studies investigating the contribution of some of these systems to guiding decision-making related to rewards vs. punishment. Lastly, we provide a brief summary of impairments in risk-related decision-making associated with psychiatric disorders, highlighting recent translational studies in laboratory animals. 相似文献
5.
The study aimed to assess the effect of exogenous factors such as surgeon posture, surgical instrument length, fatigue after a night shift, exercise and caffeine consumption on the spatial accuracy of neurosurgical manipulations. For the evaluation and simulation of neurosurgical manipulations, a testing device developed by the authors was used. The experimental results were compared using nonparametric analysis (Wilcoxon test) and multivariate analysis, which was performed using mixed models. The results were considered statistically significant at p < 0.05. The study included 11 first-year neurosurgery residents who met the inclusion criteria. Hand support in the sitting position (Wilcoxon test p value = 0.0033), caffeine consumption (p = 0.0058) and the length of the microsurgical instrument (p = 0.0032) had statistically significant influences on the spatial accuracy of surgical manipulations (univariate analysis). The spatial accuracy did not significantly depend on the type of standing position (Wilcoxon test p value = 0.2860), whether the surgeon was standing/sitting (p = 0.1029), fatigue following a night shift (p = 0.3281), or physical exertion prior to surgery (p = 0.2845).When conducting the multivariate analysis, the spatial accuracy significantly depended on the test subject (p < 0.0001), the use of support during the test (p = 0.0001), and the length of the microsurgical instrument (p = 0.0397). To increase the spatial accuracy of microsurgical manipulations, hand support and shorter tools should be used. Caffeine consumption in high doses should also be avoided prior to surgery. 相似文献
6.
《European journal of surgical oncology》2019,45(6):1039-1045
IntroductionMuch controversy exists over whether to perform lateral neck dissection (LND) on patients with papillary thyroid carcinoma (PTC). This study aimed to build predictive nomograms that could individually estimate lateral neck metastasis (LNM) risk and help determine follow up intensity.Patients and methodsUnifocal PTC patients who underwent LND between April 2012 and August 2014 were identified. Clinical and pathological variables were retrospectively evaluated using univariate and stepwise multivariate logistic regression analysis. Variables that had statistical significance in final multivariate logistic models were chosen to build nomograms, which were further corrected using the bootstrap resampling method.ResultsIn all, 505 PTC patients were eligible for analysis. Among these, 178 patients (35.2%) had lateral neck metastasis. Two nomograms were generated: nomogram (c) and nomogram (c + p). Nomogram (c) incorporated four clinical variables: age, tumor size, tumor site, and extrathyroidal extension (ETE). It had a good discriminative ability, with a C-index of 0.79 (bootstrap-corrected, 0.78). Nomogram (c + p) incorporated two clinical variables and two pathological variables: tumor size, tumor site, extranodal extension (ENE), and number of positive nodes in the central compartment. Nomogram (c + p) showed an excellent discriminative ability, with a C-index of 0.86 (bootstrap-corrected, 0.85).ConclusionTwo predictive nomograms were generated. Nomogram (c) is a clinical model, whereas nomogram (c + p) is a clinicopathological model. Each nomogram incorporates only four variables and can give an accurate estimate of LNM risk in unifocal PTC patients, which may assist clinicians in patient counseling and decision making regarding LND. 相似文献
7.
目的:对比朱氏一指禅推法联合电针与单纯电针治疗膝骨关节炎的疗效差异。方法:将100例入组患者随机分为观察组和对照组,观察治疗前、治疗3周后及治疗后3个月随访VAS评分、WOMAC量表评分及测量膝关节活动度(ROM)。结果:两组患者治疗3周后及治疗后3个月随访,VAS和WOMAC量表评分及膝关节活动度均较治疗前明显改善,差异有统计学意义(P<0.01);VAS评分两组间差异无统计学意义(P>0.05),观察组改善WOMAC量表评分及膝关节活动度均优于对照组,差异有统计学意义(P<0.01);观察组总有效率均优于对照组,差异有统计学意义(P<0.05)。结论:朱氏一指禅推法联合电针对膝骨关节炎治疗具有显著作用,尤其在改善关节僵硬、躯体功能障碍及恢复膝关节活动度方面更为明显。 相似文献
8.
IntroductionCentral venous catheter applications and complications are closely related to the tip position. Previous studies have reported some rare cases of catheter misplacement. Here, we report a case of misplacement of a peripherally inserted central catheter into the lateral thoracic vein.Case reportA 56-year-old cancer patient underwent placement of a peripherally inserted central catheter through the left basilic vein under ultrasound-guided puncture. The catheterisation procedure was uneventful, so the catheter was believed to be in the superior vena cava. However, the post-anterior chest X-ray image revealed that after the catheter advanced towards the axilla, it turned downwards and outwards in the direction of the left lateral thoracic region, with the projection of the catheter tip giving the appearance of termination in the subcutaneous tissue of the lateral thoracic wall on the two-dimensional image. The catheter was then repositioned in the distal superior vena cava.DiscussionPeripherally inserted central catheters can be potentially misplaced into the lateral thoracic vein because these catheters can pass through the orifice of the lateral thoracic vein which flows into the axillary vein. Some pathological cases and clinical conditions can cause dilatation of the lateral thoracic vein, which increases the probability of catheter misplacement. Three principles were proposed to avoid this rare complication: a comprehensive review of the patients’ medical history, real-time image-guided catheterisation and routine radiographic identification of the tip position. 相似文献
9.
Bone stock preservation is crucial when performing total hip replacement in young patients. The aim is to save good bone stock
for a possible revision procedure. Furthermore, there is an increasing demand from young and active patients to receive a
new joint which allows a normal or nearly normal life style. With this in mind, we began, in 1993, to develop a new femoral
implant. The purpose of this ultra-short stem was a physiologic strain distribution on the proximal femur with a proximal
load transfer from the implant to the femoral bone. Main features were an almost complete absence of the diaphyseal portion
of the stem, a well defined lateral flare with load transfer on the lateral column of the femur, and a very high femoral neck
cut. These innovations resulted in a conservative implant on both the bone stock and the soft tissues. This implant, in the
first years, was recommended only for young and active patients. Over the last thirteen years, this project has undergone
several modifications but the basic principles of the implant have remained the same. In the present review, we present the
rationale, the surgical technique and the clinical and experimental results so far obtained with this implant. 相似文献
10.
目的阐明针刺捻转补法与泻法的操作是否存在效应上的差异,并探讨其效应差异是否为补泻效应的差异.方法应用红外线热像技术,采用不同的捻转补泻手法针刺健康人合谷穴后,观察其在即刻,10、20、30min,对局部皮肤温度的影响.结果不同捻转补法与泻法的操作存在着不同程度的效应差异,其中补法可以使皮温升高,泻法可以使皮温降低,以石氏捻转补泻针法较为明显.结论1)补泻手法,补法和泻法的操作可产生不同的效应.2)不同捻转补泻手法对皮肤温度产生的升降效应为补泻效应,其中以石氏捻转补泻手法最为明显.3)证明补泻手法实施的必要性. 相似文献