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21.
BACKGROUND: The Delphi method provides an opportunity for experts (panelists) to communicate their opinions and knowledge anonymously about a complex problem, to see how their evaluation of the issue aligns with others, and to change their opinions, if desired, after reconsideration of the findings of the group's work. Delphi studies have the potential to provide valuable information, yet few researchers have taken further steps to support or refine their findings. Without this step there is a potential threat to the applicability, or external validity, of the results. AIMS: The purpose of this article is to present an argument for further inquiry to enhance and support Delphi findings, and specific approaches to this will be considered. METHODS: Methods to enhance, expand, or refine Delphi study findings are described. Mixed method design within a Delphi study on midwifery practice is described, and a follow-up narrative study to examine the findings is presented. FINDINGS: Selected results from the follow up narrative study are presented to convey how the narrative data clarified the Delphi findings. Together, the studies provide a more robust depiction of midwifery practice, process, and outcomes. Although there were similarities to the dimensions identified previously, there was a more dynamic focus and explanation of the interaction between the midwife, the woman who had received midwifery care, and the health care system. STUDY LIMITATIONS: Lack of diversity in the sample and the midwives' familiarity with the author's past research represent a potential threat to the findings. Prolonged interviews and multiple narratives were gathered in an effort to control for this. CONCLUSION: Delphi studies are research exercises conducted by a panel of experts. Designing studies to further enhance, clarify, or refine their findings from the context of practice holds promise for their ability to influence clinical care.  相似文献   
22.
Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections worldwide, yet no effective vaccine or antiviral treatment is available. Here we report the discovery and initial development of RSV604, a novel benzodiazepine with submicromolar anti-RSV activity. It proved to be equipotent against all clinical isolates tested of both the A and B subtypes of the virus. The compound has a low rate of in vitro resistance development. Sequencing revealed that the resistant virus had mutations within the nucleocapsid protein. This is a novel mechanism of action for anti-RSV compounds. In a three-dimensional human airway epithelial cell model, RSV604 was able to pass from the basolateral side of the epithelium effectively to inhibit virus replication after mucosal inoculation. RSV604, which is currently in phase II clinical trials, represents the first in a new class of RSV inhibitors and may have significant potential for the effective treatment of RSV disease.  相似文献   
23.
OBJECTIVES: To evaluate the characteristics of volunteers responding to emergencies in the North American Public Access Defibrillation (PAD) Trial. METHODS: The PAD Trial was a prospective evaluation of cardiac arrest survival in community facilities randomized to cardiopulmonary resuscitation (CPR) or to CPR with automated external defibrillators (AEDs). The PAD volunteers' characteristics were analyzed using Poisson regression clustered on the facility and offset by the number of emergency episodes to which volunteers were exposed. RESULTS: A total of 19,320 volunteers in 1260 facilities were trained to provide emergency care. Of these, 8169 volunteers were participating actively at their facility during a time when one or more emergency episodes occurred. There were 1971 emergency episodes responded to by 1245 volunteers. The treatment arm (CPR-only versus CPR+AED) was not associated with the likelihood of volunteer participation in an episode. Likewise, the volunteers' age or sex did not affect response. Volunteers more likely to respond were supervisory/management or security personnel, non-minority participants, volunteers with previous CPR training, volunteers with previous experience in emergency care and those who passed the PAD CPR skills follow-up test. Volunteers who had a formal education beyond a high school level were less likely to respond. CONCLUSIONS: Volunteers with previous emergency training and positions of responsibility in their facility had a greater likelihood of participation in medical emergencies in the PAD Trial.  相似文献   
24.
The control of calcitonin secretion in humans has been studied extensively only in patients with medullary thyroid carcinoma since the peripheral concentration of the hormone in normal subjects is too low for accurate measurement by existing assay procedures. However, we have recently found that the concentrations of calcitonin in the peripheral plasma of hypocalcemic subjects during provocative tests of hormone secretion were high enough to be measured by radioimmunoassay. Accordingly, the effect of calcium and pentagastrin infusions on plasma calcitonin was studied in nine patients with pseudohypoparathyroidism, seven patients with idiopathic hypoparathyroidism, and six patients with hypocalcemia not due to parathyroid disease. The infusion of calcium in these hypocalcemic subjects resulted in increases in plasma calcitonin to levels that could be readily detected by our radioimmunoassay. Pentagastrin infusion also caused an increase of plasma calcitonin in some subjects, but calcium was approximately 10 times more effective than gastrin in its stimulatory effect on hormone secretion. These results demonstrate that in humans as well as other mammals the secretion of calcitonin by parafollicular cells that are not involved by medullary thyroid carcinoma is directly related to plasma calcium and that gastrin can also stimulate hormone secretion. The results are consistent with the thesis that the secretion of calcitonin by normal human subjects does occur but at peripheral concentrations of the hormone below the detection limits of most existing immunoassays; hypocalcemia leads to increased stores of hormone that can be related by the appropriate stimuli.  相似文献   
25.
A murine monoclonal antibody (15H6) against the trichothecene mycotoxin T-2 was capable of neutralizing the in vitro protein synthesis inhibitory effect of T-2 toxin in human B lymphoblastoid cultures. It was further shown that 15H6 given to rats (250 mg/kg) 30 min before or 15 min after a lethal dose (1 mg/kg) of T-2 toxin conferred 100% survival. A lower dose of 15H6 (125 mg/kg), given 15 min after the lethal dose of T-2 toxin, protected 25% of the rats. An increased time to death and 45% survival was seen in rats given the full dose of 15H6 antibody 60 min after lethal toxin. These data are the first demonstration of effective prophylaxis and therapy for T-2 toxemia.  相似文献   
26.
Using current diagnostic criteria, primary mediastinal B cell lymphoma (PMBL) cannot be distinguished from other types of diffuse large B cell lymphoma (DLBCL) reliably. We used gene expression profiling to develop a more precise molecular diagnosis of PMBL. PMBL patients were considerably younger than other DLBCL patients, and their lymphomas frequently involved other thoracic structures but not extrathoracic sites typical of other DLBCLs. PMBL patients had a relatively favorable clinical outcome, with a 5-yr survival rate of 64% compared with 46% for other DLBCL patients. Gene expression profiling strongly supported a relationship between PMBL and Hodgkin lymphoma: over one third of the genes that were more highly expressed in PMBL than in other DLBCLs were also characteristically expressed in Hodgkin lymphoma cells. PDL2, which encodes a regulator of T cell activation, was the gene that best discriminated PMBL from other DLBCLs and was also highly expressed in Hodgkin lymphoma cells. The genomic loci for PDL2 and several neighboring genes were amplified in over half of the PMBLs and in Hodgkin lymphoma cell lines. The molecular diagnosis of PMBL should significantly aid in the development of therapies tailored to this clinically and pathogenetically distinctive subgroup of DLBCL.  相似文献   
27.
The dynamic balance of cellular sphingolipids, the sphingolipid rheostat, is an important determinant of cell fate, and is commonly deregulated in cancer. Sphingosine 1-phosphate is a signaling molecule with anti-apoptotic, pro-proliferative and pro-angiogenic effects, while conversely, ceramide and sphingosine are pro-apoptotic. The sphingosine kinases (SKs) are key regulators of this sphingolipid rheostat, and are attractive targets for anti-cancer therapy. Here we report a first-in-class ATP-binding site-directed small molecule SK inhibitor, MP-A08, discovered using an approach of structural homology modelling of the ATP-binding site of SK1 and in silico docking with small molecule libraries. MP-A08 is a highly selective ATP competitive SK inhibitor that targets both SK1 and SK2. MP-A08 blocks pro-proliferative signalling pathways, induces mitochondrial-associated apoptosis in a SK-dependent manner, and reduces the growth of human lung adenocarcinoma tumours in a mouse xenograft model by both inducing tumour cell apoptosis and inhibiting tumour angiogenesis. Thus, this selective ATP competitive SK inhibitor provides a promising candidate for potential development as an anti-cancer therapy, and also, due to its different mode of inhibition to other known SK inhibitors, both validates the SKs as targets for anti-cancer therapy, and represents an important experimental tool to study these enzymes.  相似文献   
28.
Background and aim: Cognitive impairments following brain injury, including difficulty with problem solving, can pose significant barriers to successful community reintegration. Problem-solving strategy training is well-supported in the cognitive rehabilitation literature. However, limitations in insurance reimbursement have resulted in fewer services to train such skills to mastery and to support generalization of those skills into everyday environments. The purpose of this project was to develop and evaluate an integrated, web-based programme, ProSolv, which uses a small number of coaching sessions to support problem solving in everyday life following brain injury.

Method: We used participatory action research to guide the iterative development, usability testing, and within-subject pilot testing of the ProSolv programme. The finalized programme was then evaluated in a between-subjects group study and a non-experimental single case study.

Results: Results were mixed across studies. Participants demonstrated that it was feasible to learn and use the ProSolv programme for support in problem solving. They highly recommended the programme to others and singled out the importance of the coach. Limitations in app design were cited as a major reason for infrequent use of the app outside of coaching sessions.

Conclusions: Results provide mixed evidence regarding the utility of web-based mobile apps, such as ProSolv to support problem solving following brain injury.

  • Implications for Rehabilitation
  • People with cognitive impairments following brain injury often struggle with problem solving in everyday contexts.

  • Research supports problem solving skills training following brain injury.

  • Assistive technology for cognition (smartphones, selected apps) offers a means of

  • supporting problem solving for this population.

  • This project demonstrated the feasibility of a web-based programme to address this need.

  相似文献   
29.
The emergence of clinical phonetics and linguistics as an area of scientific inquiry gives rise to the need for guidelines that define ethical and responsible conduct. The diverse membership of the International Clinical Phonetics and Linguistics Association (ICPLA) and the readership of this journal are uniquely suited to consider ethical issues from diverse perspectives. Accordingly, this paper introduces a multi‐tiered six‐factor model for ethical practices to stimulate discussion of ethical issues.  相似文献   
30.
Impairments of face recognition after acquired brain injury (ABI) are not restricted to prosopagnosia but commonly arise in association with other cognitive deficits and can be psychosocially debilitating. Despite this, the prevalence and cognitive concomitants of such impairments after ABI have not been systematically investigated. We tested 91 adults with ABI on a range of cognitive measures including several indices of face recognition and learning. The proportion of patients who show impaired performance varied across face learning/recognition tests between 21% and 80%. Principal components analyses indicated orthogonality between impairments of “directed facial processing”, associated with memory and visuoperceptual deficits and manifest in slow learning and matching of previously unfamiliar faces, and of “face identification”, associated with deficits on verbal tests and manifest in difficulty in naming famous faces. Theoretical and rehabilitative implications are considered.  相似文献   
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