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61.
Johann Steurer MD Ulrike Held PhD Lucas M. Bachmann MD PhD David Holzmann MD Peter Ott MD Olli S. Miettinen MD MPH MSc PhD 《Journal of evaluation in clinical practice》2009,15(4):614-619
Background Clinical diagnosis of acute bacterial sinusitis (ABS) is a concern when a patient presents with nasal discharge of recent onset together with facial pain or pressure. Given this presentation, the doctor would benefit from having access to software that specifies, first, what diagnostic indicators experts typically use in that diagnosis and then, upon entry of those facts, what experts' typical probability of ABS is in such a case.
Methods We specified a set of 23 hypothetical presentations of this type by patients 20–75 years of age, involving a comprehensive set of clinical-diagnostic indicators. Members of an international expert panel independently set the probability of ABS in each of these cases. A logistic function of the diagnostic indicators was fitted to the medians of the probabilities.
Results The fitting led to an expression of the experts' median probability of ABS as a joint function of the duration of the patient's facial pain/pressure, and indicators of the location(s) of this; indicators of exacerbation of the pain/pressure on bending forward, nasal obstruction, maxillary and/or frontal tenderness, pus from middle meatus, purulent postnasal drip, and fever; and indicators of recent upper respiratory tract infection, nasal polyposis and status post sinus surgery. This probability function is accessible at http://www.evimed.ch/ABS .
Interpretation That probability function, made readily accessible, provides for expertly probability setting in clinical diagnosis of ABS, relevant for decisions about further diagnostics or treatment without further tests. 相似文献
Methods We specified a set of 23 hypothetical presentations of this type by patients 20–75 years of age, involving a comprehensive set of clinical-diagnostic indicators. Members of an international expert panel independently set the probability of ABS in each of these cases. A logistic function of the diagnostic indicators was fitted to the medians of the probabilities.
Results The fitting led to an expression of the experts' median probability of ABS as a joint function of the duration of the patient's facial pain/pressure, and indicators of the location(s) of this; indicators of exacerbation of the pain/pressure on bending forward, nasal obstruction, maxillary and/or frontal tenderness, pus from middle meatus, purulent postnasal drip, and fever; and indicators of recent upper respiratory tract infection, nasal polyposis and status post sinus surgery. This probability function is accessible at http://www.evimed.ch/ABS .
Interpretation That probability function, made readily accessible, provides for expertly probability setting in clinical diagnosis of ABS, relevant for decisions about further diagnostics or treatment without further tests. 相似文献
62.
Michael L. Reno Nicole L. Held Christopher J. Fields Patricia V. Burke Rachel J. Whitaker 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(21):8605-8610
Variation in gene content has been hypothesized to be the primary mode of adaptive evolution in microorganisms; however, very little is known about the spatial and temporal distribution of variable genes. Through population-scale comparative genomics of 7 Sulfolobus islandicus genomes from 3 locations, we demonstrate the biogeographical structure of the pan-genome of this species, with no evidence of gene flow between geographically isolated populations. The evolutionary independence of each population allowed us to assess genome dynamics over very recent evolutionary time, beginning ≈910,000 years ago. On this time scale, genome variation largely consists of recent strain-specific integration of mobile elements. Localized sectors of parallel gene loss are identified; however, the balance between the gain and loss of genetic material suggests that S. islandicus genomes acquire material slowly over time, primarily from closely related Sulfolobus species. Examination of the genome dynamics through population genomics in S. islandicus exposes the process of allopatric speciation in thermophilic Archaea and brings us closer to a generalized framework for understanding microbial genome evolution in a spatial context. 相似文献
63.
64.
T D Dye H Gordon B Held N J Tolliver A P Holmes 《American journal of obstetrics and gynecology》1992,167(1):72-76
OBJECTIVE: The death of women from pregnancy-related causes remains a threat to national maternal and child health. Maternal deaths as persistent, albeit rare occurrences are overlooked if vital registration systems are relied on to report such deaths. STUDY DESIGN: Live birth records were matched with death records for women of reproductive age to detect if a woman died within 1 year of delivery. The data for potential cases were reviewed by committee and classified as maternal and nonmaternal deaths. RESULTS: Of all linked birth-death records, 32% were related to pregnancy: 81% were directly related to pregnancy and 19% were indirectly related to pregnancy. The most frequent causes of death were hemorrhage and embolism. Thirty-eight percent of the women were transferred to tertiary hospitals before death. The case ascertainment through this study improved maternal death detection by 100% over official vital statistics. CONCLUSION: Enhanced maternal mortality surveillance increased the detection of maternal death in West Virginia. Case review of these deaths yielded important information useful in shaping the state's perinatal system. 相似文献
65.
U. Burck H. W. Moser H. H. Goebel R. Grüttner K. R. Held 《European journal of pediatrics》1985,143(3):203-208
A 20-month-old girl showed typical clinical signs of Farber disease: hoarseness since birth, and periarticular subcutaneous painful nodules. Complete deficiency of acid ceramidase activity was found in cultured skin fibroblasts. An electron microscopic examination of a dermal nodule disclosed pathognomonic tubular inclusions in histiocytes. In epidermal cells zebra-body-like and needle-like lysosomal inclusions were found. Their ultrastructure is different from that of the intrahistiocytic lysosomal inclusions.Probably three clinical types of Farber disease may be distinguished according to the symptomatology and the course of the discase: a severe type, an intermediate type and a relatively mild type. The activity of acid ceramidase does not correlate with prognosis of the disease, while a correlation between first appearance of dermal nodules and clinical course appears likely. 相似文献
66.
Astigmatism and the development of myopia in children 总被引:12,自引:0,他引:12
While it is now established that astigmatism is more prevalent in infants and young children than in the adult population, little is known about the functional significance of this astigmatism, especially its role, if any, in emmetropization and the development of myopia. Manifest refractions (mean of 16 per subject) were obtained from 245 subjects starting in the first year, with 6-23 years of regular follow-up. Results showed that infantile astigmatism is associated with increased astigmatism and myopia during the school years. Two possible mechanisms underlying this association are discussed: (1) infantile astigmatism disrupts focusing mechanisms; and (2) ocular growth induces astigmatism and myopia. 相似文献
67.
The effect of oxygen tension on colony formation and cell proliferation of amniotic fluid cells in vitro 总被引:3,自引:0,他引:3
The effects of reduced oxygen concentrations in the gas phase over the culture medium on colony formation and cell proliferation were investigated in high and low cell density primary and secondary cultures of amniotic fluid cells. Using two standard culture methods (25 cm2 plastic flasks and Leighton type tubes) a significantly reduced culture time was observed at high cell density for mass cultures by incubation within a low oxygen tension gas phase (2.5 per cent to 7.5 per cent O2) instead of conventional air (18 per cent O2). At low cell density colony formation was significantly enhanced in cultures grown at reduced oxygen tension. Using gas permeable membranes as support, lowering the oxygen tension from 7.5 per cent to 2.5 per cent yielded an increase in plating efficiency of cells from approximately 5 per cent to 25 per cent, whereas plating efficiency was less than 2 per cent for cells grown at ambient 18 per cent O2. It is suggested that low oxygen tension in the gas phase is an effective means of enhancing clonal growth in amniotic fluid cell cultures, thereby reducing both culture time and risk of culture failure. 相似文献
68.
M E Rivera-Alsina L R Saldana B Held 《International journal of gynaecology and obstetrics》1984,22(4):287-289
Fifteen patients referred to the Division of Maternal-Fetal Medicine with the diagnosis of cervical incompetence were placed in a study protocol where prophylactic oral beta mimetic agents were used in an attempt to prevent cervical dilatation between 20 and 36 weeks of gestation. Our study suggest that after the first week of therapy prolonged maternal oral tocolytic therapy has no significant effect on glucose or serum potassium levels and no deleterious effects on the immediate neonatal course. 相似文献
69.
70.
BACKGROUND: Synthetic grafts have generally been found to exhibit lower survival rates and higher complication rates than native arteriovenous fistulae. We investigated whether survival of grafts relative to fistulae was better in facilities with a preference for grafts, hypothesizing that such facilities may place more grafts because grafts produced superior outcomes. METHODS: The study was based on a national U.S. sample of 133 hemodialysis facilities participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational study of dialysis treatment practices and outcomes. Vascular access preferences were ascertained from medical directors, nurse managers, and actual practice within each facility (% graft use among prevalent patients). Logistic regression was used to model the odds ratio (OR) of graft placement (vs. fistula) and Cox regression was used to model time from access creation to initial failure. RESULTS: Grafts were preferred by 21% of medical directors and 40% of nurse managers. Patients in facilities in which the medical director or nurse manager expressed a preference for grafts were more than twice as likely to have a graft than a fistula (AOR = 2.3, P < 0.01; reference group = facilities that did not prefer grafts), suggesting that facility preferences influence the type of access created. Overall, grafts were more prevalent than fistulae in dialysis facilities, but displayed a higher relative risk of failure (RR 1.33, P < 0.0001). However, the risk of graft versus fistula failure did not vary by expressed preference of the medical director: the relative risk of graft versus fistula failure was 1.39 in facilities in which the medical director preferred grafts and 1.39 in facilities in which the medical director preferred fistulae. Moreover, the relative risk of graft versus fistula failure was 1.57 in facilities that used more than the median percentage of grafts and 1.19 in facilities that used less than the median percentage of grafts. CONCLUSIONS: No evidence was found that graft outcomes are superior in facilities that prefer grafts to fistulae. The observed variation in vascular access practice patterns suggests opportunities for quality improvement if optimal practices can be defined. 相似文献