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41.
Population genetics of phenylketonuria 总被引:1,自引:0,他引:1
Phenylketonuria (PKU) is an autosomal recessive disorder caused by a large number of mutations at the phenylalanine hydroxylase (PAH) locus, most of which are strongly associated with specific RFLP or VNTR haplotypes. One of the major questions remaining in PKU research is why this apparently maladaptive disorder has been maintained at a frequency of approximately 1 in 10000 among Caucasians. A growing number of studies have provided evidence that both the relatively high frequency of PKU and the strong mutation/haplotype associations might reflect the existence of multiple founding populations for PKU. Examples of putative founding populations for PKU in both Europe and Asia will be presented. Some PAH mutations are associated with multiple haplotypes, suggesting recurrence. Evidence for and against recurrence as the mechanism responsible for the association of the R408W mutation with RFLP haplotypes 1 and 2 will be discussed. 相似文献
42.
Molecular analysis of PKU in Ireland 总被引:1,自引:0,他引:1
CA O'Neill RC Eisensmith DT Croke ER Naughten SF Cahalane SLC Woo 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):43-44
Classical phenylketonuria (PKU: McKusick No. 261600) is caused by mutations occurring at the phenylalanine hydroxylase (PAH) locus on chromosome 12 and has a prevalence in Ireland of 1 in 4500. We examined 304 independent alleles from 350 patients for the presence of six mutations and have characterized VNTR alleles within the minisatellite region 3' to the PAH gene in patients carrying the most prevalent mutation. R408W was the most common mutation found, with a relative frequency of 42%. All other mutations had relative frequencies of <10%. VNTR analysis showed that the R408W mutation is associated with the VNTR-8 allele in the Irish population, indicating that R408W is associated with RFLP haplotype 1. This differs from that reported from eastern Europe where R408W is associated with RFLP haplotype 2/VNTR-3; an observation which has led several groups to propose a Balto-Slavic origin for this mutation. These results support the hypothesis of a second, independent founding event for the R408W mutation on an RFLP haplotype 1 VNTR-8 chromsome background in the Irish/Celtic population. 相似文献
43.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored. 相似文献
44.
45.
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
46.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
47.
48.
A rare case of unilateral benign essential tremor is presented that responded to surgical excision of a posterior fossa arachnoid cyst. 相似文献
49.
BACKGROUND: Postgraduate examinations are ubiquitous in medicine worldwide, but studies to validate them are rare. The Royal College of General Practitioners of the UK, over the years in an evolving format, has offered a membership examination (MRCGP) which it believes acts as a quality marker for those who sit it and also positively influences the development of family practice generally. It is not clear, however, if this process identifies quality markers that patients can perceive. OBJECTIVES: To determine if possession of the MRCGP (a doctor defined measure of doctor quality) is associated with the patient enablement score (a patient based consultation outcome measure) and family practitioners' attitudes to the work of family practice. METHODS: Design: survey using the Patient Enablement Instrument (PEI) with linked survey data on family practitioner (FP) demography and possession of the MRCGP, and FPs' attitudes and beliefs using the Cockburn attitudinal questionnaire. Subjects: 15 534 adult patients attending 154 FP principals. Setting: 50 family practices in the UK. Outcome measures: the association between possession of MRCGP, and PEI and Cockburn scores was assessed using regression analysis controlling for known confounders. RESULTS: There was no association between PEI score and possession of the MRCGP. Only one scale of the Cockburn attitude questionnaire (the belief that patients should be involved in decision making) was positively associated with possessing the MRCGP. CONCLUSION: Any advantage in physician quality conferred by passing the MRCGP exam was not detected in this study. Further research into the predictive validity of postgraduate examinations is required preferably using a wider variety of patient and audit based methods. 相似文献
50.