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41.
Verna W. Y. Yiu Robert P. Dluhy Richard P. Lifton Lisa M. Guay-Woodford 《Pediatric nephrology (Berlin, Germany)》1997,11(3):343-346
In evaluating hypertensive children and adolescents, the etiological considerations should include a set of inherited disorders
that share very low plasma renin activity (PRA) as a common feature. In particular among these disorders, glucocorticoid remediable
aldosteronism (GRA) appears to be emerging as an important etiology of hypertension in the pediatric population. We report
the evaluation of a 9-year-old Caucasian girl who presented with severe hypertension and a strong family history of early-onset
hypertension. Her suppressed PRA, her family history, and her failure to respond to conventional antihypertensive therapy
raised GRA as a potential etiology. The diagnosis was confirmed by an elevated ratio of urinary 18-oxotetrahydrocortisol to
urinary tetrahydroaldosterone and genetic testing, which demonstrated the chimeric gene duplication. The molecular pathogenesis
of GRA and the clinical implications are reviewed.
Received May 15, 1996; received in revised form and accepted September 16, 1996 相似文献
42.
43.
Choline is needed for the maintenance of the structural integrity and signaling functions of cell membranes, for neurotransmission, and for transport of lipids and as a source of methyl groups. Choline can be made de novo in the body, but some individuals must also obtain choline in the diet to prevent deficiency symptoms. A number of environmental and genetic factors influence dietary requirements for choline, and average intakes in the population vary widely. Therefore, certain individuals may be at greater risk of choline deficiency. Choline is critical during fetal development, particularly during the development of the brain, where it can influence neural tube closure and lifelong memory and learning functions. 相似文献
44.
Dominic O''Sullivan Susan Hooper Lisa McNally Daryll Jagger 《European journal of dental education》2007,11(1):54-59
In 2000, the University of Bristol Dental School Division of Restorative Dentistry carried out a review of the assessment methods used within the undergraduate programme. Following this review, a number of key recommendations were made and the system of formative assessment within the division was changed. Audits were conducted immediately prior to the introduction of the new system and 2 years after it had been introduced, the results of these audits are presented. There was no change in the number of failed appointments between the initial audit and the second audit. There was a reduction in the number of patients treated by more than one student from 25% to 14% (approximating to 3% if student withdrawal from the course is taken into account). The length of time taken to complete treatment reduced between the two audits with more than half of all patients having their treatment completed within 3 months of their initial examination in the second audit. Ninety-five percent of treatment plans were completed in the second audit compared with only 62% in the first audit. In the second audit, the outstanding 5% of cases were signed off as incomplete for satisfactory reasons by the member of supervisory staff (e.g. patients who had moved away or were discharged due to poor attendance). Student comments were mostly positive, the small number of negative comments related to some students being confused by the paperwork in the new system. The overall process has been an extremely positive experience which has resulted in an assessment system with increased clarity which appears to have reduced the stress levels reported by the undergraduate students on the programme and improved the quality of patient care within restorative dentistry. 相似文献
45.
46.
Lisa Little 《Health services research》2007,42(3P2):1336-1353
Objective. To synthesize information about nurse migration in and out of Canada and analyze its role as a policy lever to address the Canadian nursing shortage.
Principal Findings. Canada is both a source and a destination country for international nurse migration with an estimated net loss of nurses. The United States is the major beneficiary of Canadian nurse emigration resulting from the reduction of full-time jobs for nurses in Canada due to health system reforms. Canada faces a significant projected shortage of nurses that is too large to be ameliorated by ethical international nurse recruitment and immigration.
Conclusions. The current and projected shortage of nurses in Canada is a product of health care cost containment policies that failed to take into account long-term consequences for nurse workforce adequacy. An aging nurse workforce, exacerbated by layoffs of younger nurses with less seniority, and increasing demand for nurses contribute to a projection of nurse shortage that is too great to be solved ethically through international nurse recruitment. National policies to increase domestic nurse production and retention are recommended in addition to international collaboration among developed countries to move toward greater national nurse workforce self sufficiency. 相似文献
Principal Findings. Canada is both a source and a destination country for international nurse migration with an estimated net loss of nurses. The United States is the major beneficiary of Canadian nurse emigration resulting from the reduction of full-time jobs for nurses in Canada due to health system reforms. Canada faces a significant projected shortage of nurses that is too large to be ameliorated by ethical international nurse recruitment and immigration.
Conclusions. The current and projected shortage of nurses in Canada is a product of health care cost containment policies that failed to take into account long-term consequences for nurse workforce adequacy. An aging nurse workforce, exacerbated by layoffs of younger nurses with less seniority, and increasing demand for nurses contribute to a projection of nurse shortage that is too great to be solved ethically through international nurse recruitment. National policies to increase domestic nurse production and retention are recommended in addition to international collaboration among developed countries to move toward greater national nurse workforce self sufficiency. 相似文献
47.
Delineating the sites and progression of in vivo atrophy in multiple system atrophy using fluid-registered MRI. 总被引:1,自引:0,他引:1
Jonathan M Schott Jessica E Simon Nick C Fox Andrew P King M Nadeem Khan Lisa Cipolotti Dominic C Paviour John M Stevens Martin N Rossor 《Movement disorders》2003,18(8):955-958
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA. 相似文献
48.
Cognitive models of depression propose that negative schemas contribute to depressive symptoms. Early experiences, particularly parenting, have been proposed to influence cognitive schemas and have also been shown to correlate with depression. This study explores the concurrent relationship between retrospective reports of parenting, Early Maladaptive Schemas (EMSs) described by J. E. Young (1994), and symptoms of depression in a sample of undergraduate students (N = 194). The EMSs of defectiveness/shame, insufficient self-control, vulnerability, and incompetence/inferiority were associated with perceptions of parenting and depressive symptomatology. There was evidence that these four EMSs partially mediate the relationship between parental perceptions and depressive symptomatology. Results are discussed in relation to previous findings, theory, and the measurement of EMSs. 相似文献
49.
50.
Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes
James C. Fuscoe Lisa J. Zimmerman Karen Harrington-Brock Martha M. Moore 《Environmental and molecular mutagenesis》1994,23(2):89-95
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc. 相似文献