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Pamela Charney Sarah J. Peterson 《Journal of the Academy of Nutrition and Dietetics》2013,113(11):1545
The Nutrition Care Process and Model (NCPM) provides registered dietitian nutritionists (RDNs) and dietetic technicians, registered (DTRs) a framework to recognize, diagnose, and intervene upon nutrition-related health concerns. Within the NCPM, nutrition assessment is essential to develop a comprehensive evaluation of the client’s nutrition history. The application of critical thinking skills to nutrition assessment is imperative to ensure appropriate acquisition and interpretation of data. The Academy of Nutrition and Dietetics’ Career Development Guide, adapted from the Dreyfus Model of Skill Acquisition, illustrates the progression of critical thinking skills as RDNs and DTRs gain knowledge and experience with practice. The Career Development Guide is characterized by the transition through the following stages: novice, beginner, competent, proficient, and advance practice/expert. The foundation of dietetics knowledge is obtained during the novice and beginner stages. Throughout, the primary objective is introduction of the NCPM and nutrition assessment theory via dietetics education and the application of nutrition assessment in supervised practice. Next, RDNs and DTRs transition to the competent stage of practice. During this phase, entry-level knowledge and skill are applied to patient care settings, and critical thinking skills develop as RDNs and DTRs gain experience. Subsequently, RDNs and DTRs move to the proficient stage as the ability to prioritize attention, generalize, apply problem-solving skills to new scenarios, and identify innovative solutions develops. Some RDNs and DTRs may transition to the advance practice/expert stage, during which critical thinking becomes intuitive. Critical thinking skills are essential to ensure diagnostic accuracy; however, more research is needed to further describe progression of critical thinking skills among RDNs and DTRs. 相似文献
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Vythilingam M Anderson GM Owens MJ Halaszynski TM Bremner JD Carpenter LL Heninger GR Nemeroff CB Charney DS 《The Journal of clinical endocrinology and metabolism》2000,85(11):4138-4145
CRH neurons projecting from the paraventricular nucleus (PVN) of the hypothalamus to the median eminence control hypothalamic-pituitary-adrenal (HPA) axis activity. However, CRH neurons outside the PVN as well as PVN neurons projecting to sites other than the median eminence also contribute to the stress response and may play a role in mood and anxiety disorders. We have attempted to investigate possible noradrenergic and opioid regulation of these non-HPA CRH neurons. We hypothesized that yohimbine (an alpha2-adrenergic antagonist) would have stimulatory action on non-HPA CRH neurons, whereas naloxone (a mu-opioid receptor antagonist) would not have this effect. Adult normal volunteers received i.v. yohimbine (n = 5; 0.4 microg/kg), naloxone (n = 4; 125 microg/kg), or placebo (n = 3; 0.9% saline). Cerebrospinal fluid (CSF) was collected continuously, and concentrations of CSF CRH, CSF norepinephrine (NE), and plasma cortisol were measured. Administration of either yohimbine or naloxone caused significant increases in plasma cortisol concentrations over time. Although yohimbine robustly increased CSF NE levels and appeared to increase CSF CRH levels, these effects were not seen after naloxone or placebo administration. Intraindividual correlations were not observed between the measured concentrations of plasma cortisol and CSF CRH for any of the subjects. The results support the idea that CSF CRH concentrations reflect the activity of non-HPA CRH neurons. Although both yohimbine and naloxone stimulated the HPA axis, only yohimbine appeared to have stimulatory effects on central NE and non-HPA CRH. 相似文献
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James W Murrough Katherine E Burdick Cara F Levitch Andrew M Perez Jess W Brallier Lee C Chang Alexandra Foulkes Dennis S Charney Sanjay J Mathew Dan V Iosifescu 《Neuropsychopharmacology》2015,40(5):1084-1090
The glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine displays rapid antidepressant effects in patients with treatment-resistant depression (TRD); however, the potential for adverse neurocognitive effects in this population has not received adequate study. The current study was designed to investigate the delayed neurocognitive impact of ketamine in TRD and examine baseline antidepressant response predictors in the context of a randomized controlled trial. In the current study, 62 patients (mean age=46.2±12.2) with TRD free of concomitant antidepressant medication underwent neurocognitive assessments using components of the MATRICS Consensus Cognitive Battery (MCCB) before and after a single intravenous infusion of ketamine (0.5 mg/kg) or midazolam (0.045 mg/kg). Participants were randomized to ketamine or midazolam in a 2:1 fashion under double-blind conditions and underwent depression symptom assessments at 24, 48, 72 h, and 7 days post treatment using the Montgomery–Asberg Depression Rating Scale (MADRS). Post-treatment neurocognitive assessment was conducted once at 7 days. Neurocognitive performance improved following the treatment regardless of treatment condition. There was no differential effect of treatment on neurocognitive performance and no association with antidepressant response. Slower processing speed at baseline uniquely predicted greater improvement in depression at 24 h following ketamine (t=2.3, p=0.027), while controlling for age, depression severity, and performance on other neurocognitive domains. In the current study, we found that ketamine was devoid of adverse neurocognitive effects at 7 days post treatment and that slower baseline processing speed was associated with greater antidepressant response. Future studies are required to further define the neurocognitive profile of ketamine in clinical samples and to identify clinically useful response moderators. 相似文献
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12 patients with schizophrenia and auditory hallucinations received 1 Hz transcranial magnetic stimulation of left temporoparietial cortex. In a double-blind crossover trial, active stimulation significantly reduced hallucinations relative to sham stimulation. 相似文献
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Dr. Michèle Gue BS Jean Fioramonti DS Jacques Frexinos MD M. Alvinerie BS Lionel Bueno DS 《Digestive diseases and sciences》1987,32(12):1411-1417
The effects of acoustic stress (AS) on gastrointestinal motility and their prevention by previous treatment with naloxone, phentolamine, propranolol, muscimol, and diazepam were investigated in intact and vagotomized fasted dogs fitted with chronically implanted strain gauges on the antrum at 10 cm from pylorus and on the jejunum at 70 and 140 cm from the pylorus. These effects were compared to those produced by intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Beginning 40–50 min after the occurrence of a gastric migrating motor complex (MMC), a 1-hr hearing of prerecorded intense music through earpieces (<100 dB) delayed the occurrence of the next gastric MMC observed after 2.8±1.2 hr, while jejunal MMC were still present at a normal frequency. During AS, heart rate and plasma cortisol were significantly increased by 32.7 and 215%, respectively, 10–15 min after the beginning of hearing. The AS-induced lengthening of the gastric MMC cycle as well as cortisol increase were abolished after previous administration of diazepam (0.5 mg/kg intramuscular) or muscimol (10 g/kg intravenous), while they were still present after naloxone (0.1 mg/kg intravenous), phentolamine (0.2 mg/kg intravenous), or propranolol (0.1 mg/kg intravenous). CRF administered intracerebroventricularly (100 ng/kg) also delayed the occurrence of gastric MMC without affecting jejunal motility, and this effect was not antagonized by previous treatment with diazepam or muscimol. Both the effects of AS and CRF were abolished after bilateral thoracic vagotomy. These results suggest that the selective inhibition of gastric motility induced by noise in dog is due to the CNS release of CRF which affects, in turn, the vagal output to the stomach. The suppressive action of diazepam or GABA agonist on noise-induced gastric hypomotility may be related to blockade of the AS-induced CRF release. 相似文献
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To clarify the defective erythropoiesis in eight patients with Diamond- Blackfan anemia, we studied their bone marrow response in vitro to recombinant human interleukin-3 (IL-3) and recombinant granulocyte- macrophage colony-stimulating factor (GM-CSF). In an erythropoietin- containing assay system, specimens from six of the eight patients yielded low numbers of erythroid colonies compared to control values, and in five of these no erythropoietin dose-response could be elicited. Addition of IL-3, GM-CSF or both to cultures from the six patients had no effect on CFU-E-derived colonies. In contrast, IL-3 but not GM-CSF induced a marked increase in the number (183%) and size of the BFU-E- derived colonies in five of the six cases and partially corrected the impaired dose-response to erythropoietin in four. Bone marrow from the other two patients yielded numbers of CFU-E and BFU-E colonies comparable to controls and manifested similar increments in colonies with increasing concentrations of erythropoietin. When IL-3 was added to these cultures, further increments were observed in the number and size of BFU-E colonies. We conclude that IL-3 enhanced the marrow erythropoiesis in most of the patients and exerted a corrective effect on the aberrant colony formation in the presence of erythropoietin. The data raise the possibility of IL-3 as a therapeutic agent in Diamond- Blackfan anemia. 相似文献