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51.
PURPOSE: This study was conducted to assess whether neonatal nurses who care for dying infants could be assisted in their knowledge and comfort via an educational intervention provided by hospital ethics committee members and hospice specialists. PARTICIPANTS: Eighty-two registered nurses working in a level III neonatal intensive care unit (NICU) were included. METHODS AND DESIGN: This was a quantitative pretest, intervention, post-test design with a single group undergoing educational sessions in the 6 areas of pain management, symptom management, ethical/legal issues, communication/culture, spiritual/anxiety, and prevention of compassion fatigue. MAIN OUTCOME MEASUREMENTS: An instrument, "Comfort in Caring for Dying Infants" (CLCDI), was developed to assess pre- and posteducational knowledge and comfort in these areas. RESULTS: There were statistically significant higher levels of comfort and knowledge in care for dying infants in the areas of ethical/legal issues and symptom management after the educational programs. Although not statistically significant, mean scores were higher after the educational sessions on pain management, spirituality/anxiety, and prevention of compassion fatigue. The communication/culture module scores were lower in the post-test administration. CONCLUSIONS: Education by hospice experts in the NICU can assist nurses' comfort with care of the dying infant. In addition, ongoing support is highly desirable for all staff participating in such care. The authors suggest incident debriefings from outside experts, debriefing after each infant's death, multidisciplinary meetings for the whole team, and having sessions of lessons learned on infant death cases.  相似文献   
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53.

Background

Few studies have validated bioelectrical impedance analysis (BIA) following bariatric surgery.

Methods

We examined agreement of BIA (Tanita 310) measures of total body water (TBW) and percent body fat (%fat) before (T0) and 12 months (T12) after bariatric surgery, and change between T0 and T12 with reference measures: deuterium oxide dilution for TBW and three-compartment model (3C) for %fat in a subset of participants (n?=?50) of the Longitudinal Assessment of Bariatric Surgery-2.

Results

T0 to T12 median (IQR) change in deuterium TBW and 3C %fat was ?6.4 L (6.4 L) and ?14.8 % (13.4 %), respectively. There were no statistically significant differences between deuterium and BIA determined TBW [median (IQR) difference: T0 ?0.1 L (7.1 L), p?=?0.75; T12 0.2 L (5.7 L), p?=?0.35; Δ 0.35 L(6.3 L), p?=?1.0]. Compared with 3C, BIA underestimated %fat at T0 and T12 [T0 ?3.3 (5.6), p?<?0.001; T12 ?1.7 (5.2), p?=?0.04] but not change [0.7 (8.2), p?=?0.38]. Except for %fat change, Bland-Altman plots indicated no proportional bias. However, 95 % limits of agreement were wide (TBW 15–22 L, %fat 19–20 %).

Conclusions

BIA may be appropriate for evaluating group level response among severely obese adults. However, clinically meaningful differences in the accuracy of BIA between individuals exist.  相似文献   
54.

Objective:

To describe the theory and methodology of the multi-wave, prospective Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) study. The goal of MAVAN is to examine the pre- and postnatal influences, and their interaction, in determining individual differences in mental health.

Method:

MAVAN is a community-based, birth cohort study of pregnant Canadian mothers and their offspring. Dyads are assessed longitudinally, with multiple assessments of both mother and child in home and laboratory across the child’s development. Study measures, including assessments of cognitive and emotional function, are described. The study uses a candidate gene approach to examine gene–environment interdependence in specific developmental outcomes. Finally, the study includes measures of both brain-based phenotypes and metabolism to explore comorbidities associated with child obesity. One of the unique features of the MAVAN protocol is the extensive measures of the mother–child interaction. The relation between these measures will be discussed.

Results:

Evidence from the MAVAN project shows interesting results about maternal care, families, and child outcomes. In our review, preliminary analyses showing the correlations between measures of maternal care are reported. As predicted, early evidence suggests that maternal care measures are positively correlated, over time.

Conclusions:

This review provides evidence for the feasibility and value of laboratory-based measures embedded within a longitudinal birth cohort study. Though retention of the samples has been a challenge of MAVAN, they are within a comparable range to other studies of this nature. Indeed, the trade-off of somewhat greater participant burden has allowed for a rich database. The results yielded from the MAVAN project will not only describe typical development but also possible targets for intervention. Understanding certain endophenotypes will shed light on the pathogenesis of various mental and physical disorders, as well as their interrelation.  相似文献   
55.
Cocaine functions, in part, through agonist actions at sigma‐1 (σ1) receptors, while roles played by sigma‐2 (σ2) receptors are less established. Attempts to discriminate σ2 receptor‐mediated effects of cocaine in locomotor hyperactivity assays have been hampered by the lack of potent and selective antagonists. Certain tetrahydroisoquinolinyl benzamides display high σ2 receptor affinity, and excellent selectivity for binding to σ2 over σ1 receptors. The behavioral properties of this structural class of σ ligands have not yet been investigated. The present study evaluated 5‐bromo‐N‐[4‐(6,7‐dimethoxy‐3,4‐dihydro‐1H‐isoquinolin‐2‐yl)‐butyl)]‐2,3‐dimethoxy‐benzamide, 1 , a ligand shown by others to bind preferentially to σ2 over σ1 receptors, as well as dopamine D2 and D3 sites. First, we determined binding to monoamine transporters and opioid receptors, and noted 57‐fold selectivity for σ2 receptors over the serotonin transporter, and >800‐fold selectivity for σ2 receptors over the other sites tested. We then examined 1 in locomotor activity studies using male CD‐1® mice, and saw no alteration of basal activity at doses up to 31.6 µmol/kg. Cocaine produced a fivefold increase in locomotor activity, which was attenuated by 66% upon pretreatment of mice with 1 at 31.6 µmol/kg. In vivo radioligand binding studies also were performed, and showed no occupancy of σ1 receptors or the dopamine transporter by 1 , or its possible metabolites, at the 31.6 µmol/kg dose. Thus, ligand 1 profiles behaviorally as a σ2 receptor‐selective antagonist that is able to counteract cocaine's motor stimulatory effects. Synapse 68:73–84, 2014 . © 2013 Wiley Periodicals, Inc.  相似文献   
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58.
Tissue pH is an indicator of altered cellular metabolism in diseases including stroke and cancer. Ischemic tissue often becomes acidic due to increased anaerobic respiration leading to irreversible cellular damage. Chemical exchange saturation transfer (CEST) effects can be used to generate pH-weighted magnetic resonance imaging (MRI) contrast, which has been used to delineate the ischemic penumbra after ischemic stroke. In the current study, a novel MRI ratiometric technique is presented to measure absolute pH using the ratio of CEST-mediated contrast from amine and amide protons: amine/amide concentration-independent detection (AACID). Effects of CEST were observed at 2.75 parts per million (p.p.m.) for amine protons and at 3.50 p.p.m. for amide protons downfield (i.e., higher frequency) from bulk water. Using numerical simulations and in vitro MRI experiments, we showed that pH measured using AACID was independent of tissue relaxation time constants, macromolecular magnetization transfer effects, protein concentration, and temperature within the physiologic range. After in vivo pH calibration using phosphorus (31P) magnetic resonance spectroscopy (31P-MRS), local acidosis is detected in mouse brain after focal permanent middle cerebral artery occlusion. In summary, our results suggest that AACID represents a noninvasive method to directly measure the spatial distribution of absolute pH in vivo using CEST MRI.  相似文献   
59.
60.
The aim of this study was to examine relations of emotional variability during mother–adolescent conflict interactions in early adolescence with adolescent disclosure and maternal control in early and late adolescence. Data were used from 92 mother–adolescent dyads (M age T1 = 13.05; 65.20% boys) that were videotaped at T1 while discussing a conflict. Emotional variability was derived from these conflict interactions. Mothers also completed questionnaires at the start of the study (T1) and five years later (T6) on adolescent disclosure and maternal control. Path analysis showed that more emotional variability during conflict interactions in early adolescence was associated with higher levels of adolescent disclosure in early adolescence and with relative decreases in maternal control from early to late adolescence. More emotional variability of mother–adolescent dyads serves an important function in adaptively dealing with relational challenges that arise during adolescence.  相似文献   
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