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1.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5
Background
Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery. 相似文献2.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
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A randomized controlled trial of sedation in the critically ill 总被引:2,自引:0,他引:2
LYNN PARKINSON RSCN JULIE HUGHES RSCN REA GILL MSc IMOGEN BILLINGHAM BM FRCA JANE RATCLIFFE MB ChB FRCP & IMTI CHOONARA MD MRCP 《Paediatric anaesthesia》1997,7(5):405-510
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children. 相似文献
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols. 相似文献
9.
John Hopkins Ian McConnell Robert G. Dalziel Bernadette M. Dutia 《European journal of immunology》1993,23(11):2889-2896
This study characterizes antigen-induced phenotypic and functional aspects of major histocompatibility complex (MHC) class II expression on recirculating T cells in efferent lymph. In vivo secondary, but not primary challenge is associated with both kinetic and phenotypic alterations in class II expression by T cells. All three major T cell subsets, CD4+, CD8+ and T19+ (γδ T cell receptor), show an approximate four fold increase in the level of MHC class II expression during secondary responses. No changes in B cell expression of class II were seen. Resting efferent lymph T cells are predominantly either class II? or DR+DQ? but this changes to DR+DQ+ after antigenic challenge. The antigen-presenting function of these class II+ T cells was investigated at daily intervals after in vivo antigenic challenge. T cells from non-activated lymph nodes could not induce proliferation of antigen-specific T cells with soluble antigen but were weakly stimulatory in allo-mixed lymphocyte reaction (MLR) at high (> 2:1) stimulator cell ratios. Activated T cells isolated during secondary in vivo responses, and expressing increased quantities of MHC class II, were positive stimulator cells in the MLR. In contrast these cells could not present soluble antigen or trypsin-digested antigen to the T cell lines. In the MLR assays, the relative stimulation by class II+ T cells correlates with the levels of class II expression. We conclude from these experiments that both quantitative and qualitative changes in MHC class II, induced on T cells under physiological conditions, play a role in the regulation of the immune response in vivo but that that role is not simply one of presentation of soluble antigen. 相似文献
10.
M. B. Dutia Alexander R. Johnston 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,118(2):148-154
The postnatal maturation of medial vestibular nucleus (MVN) neurones was examined in slices of the dorsal brainstem prepared
from balb/c mice at specific stages during the first postnatal month. Using spike-shape averaging to analyse the intracellularly recorded
action potentials and after-hyperpolarisations (AHPs) in each cell, all the MVN neurones recorded in the young adult (postnatal
day 30; P30) mouse were shown to have either a single deep AHP (type A cells), or an early fast and a delayed slow AHP (type
B cells). The relative proportions of the two subtypes were similar to those in the young adult rat. At P5, all the MVN cells
recorded showed immature forms of either the type A or the type B action potential shape. Immature type A cells had broad
spontaneous spikes, and the characteristic single AHP was small in amplitude. Immature type B cells had somewhat narrower
spontaneous spikes that were followed by a delayed, apamin-sensitive AHP. The delayed AHP was separated from the repolarisation
phase of the spike by a period of isopotentiality. Over the period P10–P15, the mean resting potentials of the MVN cells became
more negative, their action potential fall-times became shorter, the single AHP in type A cells became deeper, and the early
fast AHP appeared in type B cells. Until P15 cells of varying degrees of electrophysiological maturity were found in the MVN
but by P30 all MVN cells recorded were typical adult type A or type B cells. Exposure to the selective blocker of SK-type
Ca-activated K channels, apamin (0.3 μM), induced depolarising plateaux and burst firing in immature type B cells at rest.
The duration of the apamin-induced bursts and the spike frequency during the bursts were reduced but not abolished after blockade
of Ca channels in Ca-free artificial cerebrospinal fluid containing Cd2+. By contrast, in mature type B cells at rest apamin selectively abolished the delayed slow AHP but did not induce bursting
activity. Apamin had no effect on the action potential shape of immature type A cells. These data show that the apamin-sensitive
I
AHP is one of the first ionic conductances to appear in type B cells, and that it plays an important role in regulating the intrinsic
rhythmicity and excitability of these cells.
Received: 19 November 1996 / Accepted: 30 June 1997 相似文献