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51.
Summary Transcatheter inferior phrenic arterial (IPA) and hepatic arteriography was performed on 38 patients with advanced primary
hepatic carcinoma (PHC) with blood supplied by IPA and hepatic artery. 18 patients received single treatment with hepatic
arterial infusion (HAI) or embolization (HAE) 20 received double treatment with IPA and hepatic arterial infusion or embolization.
The results show that the double treatment is superior to the single one. The angiographic features and mechanism of parasitization
of inferior phrenic arterial supply to PHC were also discussed. 相似文献
52.
本文报告2例布加氏综合征经肝裸区腔房转流术.2例均为Hirooka Ib型,术毕测下腔静脉压力,分别由术前2.75kPa和3.73kPa降至1.67kPa和1.87kPa.术后症状体征迅速消失.随访50和24个月效果良好,说明满意的压力降低是手术成功的重要标准.Hirooka Ia,Ib,Ic及Ⅳ型首选本术式的优点是:①移植人工血管短,通畅率高;②不易受压;③符合正常血液动力学;④只一个切口,创伤较小. 相似文献
53.
Bernhard J. Connemann Heidrun Busche Jürgen Kreusch Helmut H. Wolff 《Skin research and technology》1996,2(1):40-48
Background/aims: Quantitative measurement of skin roughness has proved to be a valuable tool in the efficacy-control of external applications, but it suffers from not yielding easily comparable results. The most important sources of inter-observer variability are high-pass filters used to separate roughness and waviness, and low-pass filters which result from the finite resolution of the instrument or from the finite sampling interval of digital measurement. In the present study, the effects of high-pass filters and sampling intervals on the roughness measured were investigated. Methods: Dynamically focusing optical profilometry was used to measure the surfaces of negative replicas of healthy human skin. High-pass cut-off wavelengths and sampling intervals were varied systematically. Results/conclusions: Virtually unbiased estimates for the roughness parameters K, Sk, Rq, and Ra can be obtained using sampling intervals of 40 or even 80 μm. Regarding these roughness parameters, it is far better to do more scans than to shorten the sampling interval. The roughness parameters Rz, Rp, Rt, Rpm, Rmax, Pt, on the other hand are very sensitive to the influence of the sampling interval; to achieve satisfying estimates, the sampling interval should be no longer than 2 to 5 urn; as an important parameter’of the measurement, it is worthy of remark and should always be indicated. The way the mean square roughness Rq depends on the cut-off wavelength is not well described by the Sayles-Thomas-relation Rq~λc0.5. If the power-spectrum |h*(v)|2 approximates sufficiently to a power law, |h*(v)|2~vδ, a better estimate is given by Rq~λcγ with γ=-(δ+1)/2. In many cases, γ=1 or Rq~λc will suffice. 相似文献
54.
Measurements of IgE levels in the blood of neonates were investigated using filter paper for blood collection in mass screening of congenital metabolic disorders. Time-resolved fluoroimmunometric assay system for the measurement of filter paper blood IgE levels was also studied. In an analysis of the present results, IgE values of at least 0.015U/ml, the measurement limit, were considered as high. High IgE levels in filter paper blood were seen in 28 (7.2%) of the 389 cases. When the relation with serum IgE levels at 18 months of age was investigated in 134 of 389 subjects, high serum IgE levels were also found in about 86.7% of the subjects with high IgE levels in filter paper blood. In addition, when the relation between family history of atopic disease and presence of atopic disease in the first 18 months of age was investigated in 203 of the 389 subjects, about 90% of the subjects with a family history of atopic disease and high IgE levels in filter paper blood developed atopic disease. Since filter paper blood is routinely collected in Japan, IgE levels in this blood should be widely checked for the prediction of onset of atopic disease in infants. 相似文献
55.
Summary A simple organ culture method for culturing embryonic skin was developed. A piece of skin with a part of the neural tube from mouse embryo (11 to 12 d) was placed on a 25 mm d membrane filter. The filter was folded to wrap the explant and inserted into glass tubing. The explant and filter in the glass tubing were placed in a rotating tissue culture tube containing 5 ml culture medium (Ham's F12 supplemented with 15 to 20% fetal bovine serum) and filled with a mixture of 95% air:5% CO2. In explants cultured for 6 d fully differentiated melanocytes were observed in the epidermis. 相似文献
56.
Fluid Flow through Filtering Appendages of Insects 总被引:4,自引:0,他引:4
Many organisms use structures composed of arrays of cylindersto capture particulate food or molecules form the water or airaround them. The performance of such filters depends on thevelocity of fluid movement through them; hence, mathematicalmodels of flow through fibrous structures can provide insightsabout the functional morphology of biological filters. In thispaper, the authors address the case of feather-like biologicalfilters of finite width and assess several possible models forfluid motion through them by comparing model predictions withobservational data. Two examples of insect appendages are considered:the cephalic fans of black fly aquatic larvae that capture particulatefood and the antennae of adult male moths that catch sex-attractantmolecules released by female moths. The results suggest thatflow through such structures can be much slower than ambientcurrents, that the finest hairs in the structure are the morphologicalfeatures with the greatest effect on leakiness, and that thevelocity of movement (or of ambient flow), as well as the morphologyof such filters, can be critical in determining their performance. 相似文献
57.
在观察和测量100个上肢解剖标本的基础上,我们设计了带血管的胸背神经和下肩胛下神经移位,一期修复一例火器性肌皮神经和腋神经损伤.术后8个月复查功能恢复甚为满意. 相似文献
58.
59.
A Parametric Approach to Measuring Cerebral Blood Flow Autoregulation from Spontaneous Variations in Blood Pressure 总被引:2,自引:0,他引:2
Autoregulation maintains cerebral blood flow (CBF) almost constant in the face of changes in arterial blood pressure (ABP). Tests for impairment of this process using only spontaneous fluctuations in ABP, without provoking large variations, are of great clinical interest, and a range of different approaches have previously been applied. Extending earlier work based on linear filters, we propose a simple parametric method using a first order finite impulse response filter. We evaluate the method on ABP and CBF velocity [(CBFV), from trancranial Doppler ultrasound] signals collected in 60 patients with stenosis or occlusion of the carotid arteries. Data were collected during the inspiration of ambient air, a 5% CO2/air mixture, and finally the return to ambient air. Equivalent data were collected in 15 normal subjects. The filters estimated from the data segments with constant inspiratory pCO2 showed the expected high-pass characteristic, which was reduced during hypercapnia and also in patients. Highly significant correlation between the filter parameters and cerebrovascular reactivity (percent increase in CBFV per unit change in end-tidal pCO2) gives further evidence that the filters reflect autoregulation. The method allows simple parametrization of the dynamic autoregulatory responses in CBFV, and the analysis of short (1 min) data segments. © 2001 Biomedical Engineering Society.
PAC01: 8719Uv, 4762+q, 4380Qf 相似文献
60.
P. Bonnichon F. Gaudard E. Ouakil P. Lebozec C. de Labrouhe A. Bonnin C. Aaron Y. Chapuis 《Surgical and radiologic anatomy : SRA》1989,11(2):149-154
Summary Placement of a transvenous vena cava filter has became a common way to control recurrent pulmonary embolism. However few studies have been reported on the diameter of the infrarenal inferior vena cava (IIVC) where the device is usually placed. This study based upon 100 cavographies has showed the calculated average diameter of IIVC was 20.9 mm (range 12–27 mm) in its middle part and 21.3 mm (range 10–31 mm) in its terminal end. The calculated average IIVC length was 96 mm (range 80.3–142 mm). There was no statistical correlation between caval size and age, sex, height, weight and corporeal area. There was a statistical difference of left renal vein location between patients presenting with lumbar arthrosis and those without. We discuss different methods to measure IIVC in particular tomodensitometry. CT scans reviewed in our department show that the largest diameter of IIVC is not in a frontal plane and that the width seen on cavography is the projection of the largest diameter on the film. Therefore, the range of the real caval diameters is greater than indicated above.
Biométrie de la v. cave inférieure sous-rénale: mesure par cavographieApplication clinique
Résumé L'utilisation de filtre cave endoveineux pour prévenir une récidive d'embolie pulmonaire est devenue d'un usage courant. Cependant peu de travaux ont été faits sur le diamètre de la veine cave inférieure infrarénale (IIVC) où l'appareil est généralement situé. Cette étude a pour but d'étudier le diamètre transversal de la VCI sousrénale (VCISR) à partir de 100 cavographies réalisées dans des conditions techniques identiques. Le diamètre moyen de la VCISR est de 20.9 mm (extrême 12–27 mm) dans sa partie moyenne et de 21.3 mm (extrême 10–31 mm) au niveau de sa terminaison. La longueur moyenne de la VCISR est de 96 mm (extrême 80,3–142 mm). L'âge, le sexe, la taille, le poids, la surface corporelle n'influencent pas les dimensions de la VCISR. Il existe une différence statistiquement significative de l'abouchement de la v. rénale gauche entre les sujets ayant une arthrose lombaire et ceux qui en sont dépourvus.La cavographie reste un examen de base en matière d'exploration de la VCI. La connaissance des variations des dimensions de la VCISR qu'elle apporte est donc indispensable. L'intérêt de cette étude est cependant limité par le fait que l'image radiologique correspond en réalité à la projection du diamètre transversal réel. Des études complémentaires utilisant en particulier la tomodensitométrie sont donc nécessaire pour préciser une éventuelle relation entre le diamètre réel et le diamètre mesuré par cavographie.相似文献